G2Cdb::Gene report

Gene id
Gene symbol
Homo sapiens
basigin (Ok blood group)
G00000328 (Mus musculus)

Databases (8)

ENSG00000172270 (Ensembl human gene)
682 (Entrez Gene)
664 (G2Cdb plasticity & disease)
BSG (GeneCards)
109480 (OMIM)
Marker Symbol
HGNC:1116 (HGNC)
Protein Expression
2427 (human protein atlas)
Protein Sequence
P35613 (UniProt)

Synonyms (2)

  • CD147

Literature (149)

Pubmed - other

  • Annexin II promotes invasion and migration of human hepatocellular carcinoma cells in vitro via its interaction with HAb18G/CD147.

    Zhao P, Zhang W, Tang J, Ma XK, Dai JY, Li Y, Jiang JL, Zhang SH and Chen ZN

    Department of Cell Biology, State Key Laboratory of Cancer Biology, State Key Discipline of Cell University, Fourth Military Medical University, Cell Engineering Research Center, Xi'an, China.

    HAb18G/CD147, a member of the immunoglobulin family enriched on the surface of tumor cells, is reported to be correlated with invasion, metastasis, growth, and survival of malignant cells. Here, we found that annexin II, a 36-kDa Ca(2+)- and phospholipid-binding protein and in vivo substrate for tyrosine kinase and PKC, is a new interaction protein of HAb18G/CD147 in human hepatocellular carcinoma (HCC) cells. In the present study, we explored the unclear role of annxin II in HCC invasion and migration and the interaction effects between HAb18G/CD147 and annexin II. Our data show that downregulation of annexin II in HCC cells significantly decreased the secretion of MMP, migration ability, and invasive potential, and affected the cytoskeleton rearrangement of tumor cells. The MMP-2 level and invasive potential of HCC cells were regulated by both annexin II and HAb18G/CD147. Also, interaction effects exist between the two molecules in tumor progression, including MMP-2 production, migration, and invasion. These results suggest that annexin II promotes the invasion and migration of HCC cells in vitro, and annexin II and HAb18G/CD147 interact with each other in the same signal transduction pathway working as a functional complex in tumor progression.

    Cancer science 2010;101;2;387-95

  • Target chemotherapy of anti-CD147 antibody-labeled liposome encapsulated GSH-DXR conjugate on CD147 highly expressed carcinoma cells.

    Matsudaira H, Asakura T, Aoki K, Searashi Y, Matsuura T, Nakajima H, Tajiri H and Ohkawa K

    Department of Biochemistry, Jikei University School of Medicine, Tokyo 105-8461, Japan. hi-matz48@jikei.ac.jp

    It was confirmed that CD147 (Emmprin) was expressed on the cell surface of carcinoma cells. For the purpose of studying the efficacy of a CD147-targeting agent on CD147-expressing carcinoma cells, we investigated the effect of a conjugate of glutathione-doxorubicin (GSH-DXR) encapsulated in an anti-CD147 antibody-labeled liposome (aCD147ab-liposome) in terms of specific accumulation and cytotoxicity in CD147-expressing human carcinoma cells. Expression of CD147 was not observed in many normal human tissues. However, slight expression of CD147 in kidney, prostate and breast tissues was observed. By contrast, high-level expression of CD147 in all carcinoma cells such as A431, PC3 and Ishikawa cell lines was confirmed by fluorescent microscopy and Western blot analysis. Specific accumulation of the aCD147ab-liposome in the above-described CD147-expressing cells was observed. GSH-DXR encapsulated in an aCD147ab-liposome expressed specific cytotoxicity against these carcinoma cells. These results suggested that target chemotherapy of GSH-DXR encapsulated in an aCD147ab-liposome on CD147-expressing carcinoma cells was effective.

    International journal of oncology 2010;36;1;77-83

  • Structure of the EMMPRIN N-terminal domain 1: dimerization via beta-strand swapping.

    Luo J, Teplyakov A, Obmolova G, Malia T, Wu SJ, Beil E, Baker A, Swencki-Underwood B, Zhao Y, Sprenkle J, Dixon K, Sweet R and Gilliland GL

    Centocor R&D, Inc., 145 King of Prussia Road, Radnor, Pennsylvania 19087, USA. jluo@its.jnj.com

    Proteins 2009;77;4;1009-14

  • Vasculogenic mimicry of human ovarian cancer cells: role of CD147.

    Millimaggi D, Mari M, D' Ascenzo S, Giusti I, Pavan A and Dolo V

    Department of Health Sciences, L'Aquila University, L'Aquila, Italy.

    The term vasculogenic mimicry (VM) indicates the process by which aggressive tumor cells are able to generate in vitro non-endothelial cell-lined channels delimited by extracellular matrix. Although VM has been described in several human malignancies, the molecular basis of this phenomenon is not entirely understood. In the present study, we examined VM in two ovarian cancer cell lines with different invasion capability (CABA I, low invasion activity; SKOV3, high invasion activity). Specifically, we focused on the potential role played by CD147/extracellular MMP inducer, a membrane spanning molecule highly expressed in tumor cells, in VM. Previous studies have shown that CD147 may be involved in the progression of malignancies by regulating the expression of metalloproteinases in peritumoral stromal cells. In this study, we found significant correlations between expression of CD147 in ovarian cancer cell lines and tumor invasiveness, the activity of the proteases and the ability to form vascular channels. The treatment of SKOV3 cells with small interfering RNA against CD147 suppressed the ability of these cells to generate non-endothelial cell-lined channels. In contrast, transfection of CD147 cDNA into the CABA I cell line resulted in an increased tumor invasiveness and enabled the formation of vascular channels. Altogether, our data suggest that CD147 may play a critical role in VM of CABA I and SKOV3, human ovarian cancer cell lines.

    International journal of oncology 2009;35;6;1423-8

  • Upregulation of caveolin-1 and CD147 expression in nasopharyngeal carcinoma enhanced tumor cell migration and correlated with poor prognosis of the patients.

    Du ZM, Hu CF, Shao Q, Huang MY, Kou CW, Zhu XF, Zeng YX and Shao JY

    State Key Laboratory of Oncology in Southern China, Sun Yat-Sen University Cancer Center, Guangzhou 510060, People's Republic of China.

    Expression of caveolin-1 (Cav-1) and extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) and their prognostic significance were analyzed in archive NPC samples. Cav-1 and CD147 were overexpressed in 49.48% (96/194) and 59.39% (117/197) of NPC, respectively. Both Cav-1 and CD147 expression levels correlated significantly with metastasis (p = 0.025 and 0.017, respectively) and a lower 5-year survival rate (p = 0.02 and 0.0009, respectively). In addition, Cav-1 expression levels correlated significantly with local recurrence (p = 0.038). Multivariate Cox regression analysis indicated that combination of high Cav-1 and CD147 expression was a significant, independent prognosis predictor in patients with NPC (HR = 2.135; p = 0.006). Functional studies revealed that overexpression of Cav-1 promoted secretion of MMP-3 and MMP-11 (active) proteins, as well as an increase in the migratory ability of CNE1 and CNE2 cells, while siRNA-mediated silencing of Cav-1 or CD147 led to reduced levels of MMP-3 and MMP-11(active) secretion, and reduced migration capacity of CNE1 and CNE2 cells. We observed a positive correlation between Cav-1 and CD147 expression in NPC (rho = 0.330, p = 0.000), CD147 protein levels were upregulated in Cav-1 overexpressing CNE1 and CNE2 cells, whereas siRNA-mediated silencing of Cav-1 led to the downregulation of CD147 expression. Our results indicate that Cav-1 and CD147 overexpression predict poor NPC prognosis and enhanced tumor cell migration, which is associated with MMP-3 and MMP-11 (active) secretion.

    International journal of cancer 2009;125;8;1832-41

  • Morphological changes and molecular expressions of hepatocellular carcinoma cells in three-dimensional culture model.

    Wu YM, Tang J, Zhao P, Chen ZN and Jiang JL

    Cell Engineering Research Centre and Department of Cell Biology, State Key Laboratory of Cancer Biology, The Fourth Military Medical University, 17 West Changle Road, Xi'an 710032, People's Republic of China.

    Metastatic processes of hepatocellular carcinoma (HCC) are highly associated with the breakdown of extracellular matrix (ECM). However, the regular two-dimensional (2D) culture system, in which only little ECM is involved, fails to provide a well-defined microenvironment for HCC functional research. HAb18G/CD147, a HCC-associated antigen, plays important roles in HCC progression, migration and invasion. In this study, we investigated whether HAb18G/CD147 enhanced the HCC migration and invasion in three-dimensional (3D) culture model through affecting the key molecules and enzymes involved in the metastatic processes, such as focal adhesion kinase (FAK), matrix metalloproteinases (MMPs) and cytoskeleton proteins. We found that, compared with those in 2D cell culture model, the expression of HAb18G/CD147 was significantly increased in 3D cell culture model, together with a high production of MMPs (P<0.01), an enhanced expression and activation of FAK (P<0.01) and a changed distribution of F-actin. In addition, the expressions of paxillin and E-cadherin, which enhance the adhesion and migration potentials, were also significantly increased in 3D cell culture model (P<0.01). All the results suggest that the enhanced expressions of HAb18G/CD147, MMPs, paxillin and FAK changed the distributions of cytoskeleton in the 3D reconstituted basement membrane (BM) and increased the adhesion and invasion potentials of HCC cells.

    Experimental and molecular pathology 2009;87;2;133-40

  • Nitric oxide induces the progression of abdominal aortic aneurysms through the matrix metalloproteinase inducer EMMPRIN.

    Lizarbe TR, Tarín C, Gómez M, Lavin B, Aracil E, Orte LM and Zaragoza C

    Institutional Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid 28029, Spain.

    Nitric Oxide (NO) is involved in the development and progression of abdominal aortic aneurysms (AAA). We found that inhibition of inducible NO synthase (iNOS) protects mice in an elastase-induced AAA model, significantly inhibiting the production of matrix metalloproteinase-13 (MMP-13). The extracellular MMP inducer (EMMPRIN; CD147) was increased in human AAA biopsies and in wild-type murine AAA but not in AAA from iNOS null mice. In cells overexpressing ectopic EMMPRIN, MMP-13 secretion was stimulated, whereas silencing of EMMPRIN by RNA interference led to significant inhibition of MMP-13 expression. In addition, elastase infusion of MMP-13 null mouse aortas induced a significant increase of EMMPRIN but reduced aortic dilatation when compared with wild-type mice, suggesting that NO-mediated AAA may be mediated through EMMPRIN induction of MMP-13. These findings were further verified in elastase-infused iNOS null mice, in which daily administration of NO caused a significant aortic dilatation and the expression of EMMPRIN and MMP-13. By contrast, in iNOS wild-type mice, pharmacological inhibition of iNOS by administration of 1400 W induced a reduction of aortic diameter and inhibition of MMP-13 and EMMPRIN expression when compared with control mice. Our results suggest that NO may regulate the development of AAA in part by inducing the expression of EMMPRIN and modulating the activity of MMP-13 in murine and human aneurysms.

    The American journal of pathology 2009;175;4;1421-30

  • The interaction of HAb18G/CD147 with integrin alpha6beta1 and its implications for the invasion potential of human hepatoma cells.

    Dai JY, Dou KF, Wang CH, Zhao P, Lau WB, Tao L, Wu YM, Tang J, Jiang JL and Chen ZN

    Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, No.17 West Changle Road, Xi'an 710032, Shaanxi, PR China. daijingyao2008@gmail.com

    Background: HAb18G/CD147 plays pivotal roles in invasion by hepatoma cells, but the underlying mechanism remains unclear. Our previous study demonstrated that overexpression of HAb18G/CD147 promotes invasion by interacting with integrin alpha3beta1. However, it has never been investigated whether alpha3beta1 is solely responsible for this process or if other integrin family members also interact with HAb18G/CD147 in human hepatoma cells.

    Methods: Human SMMC-7721 and FHCC98 cells were cultured and transfected with siRNA fragments against HAb18G/CD147. The expression levels of HAb18G/CD147 and integrin alpha6beta1 were determined by immunofluorescent double-staining and confocal imaging analysis. Co-immunoprecipitation and Western blot analyses were performed to examine the native conformations of HAb18G/CD147 and integrin alpha6beta1. Invasion potential was evaluated with an invasion assay and gelatin zymography.

    Results: We found that integrin alpha6beta1 co-localizes and interacts with HAb18G/CD147 in human hepatoma cells. The enhancing effects of HAb18G/CD147 on invasion capacity and secretion of matrix metalloproteinases (MMPs) were partially blocked by integrin alpha6beta1 antibodies (P < 0.01). Wortmannin, a specific phosphatidylinositol kinase (PI3K) inhibitor that reverses the effect of HAb18G/CD147 on the regulation of intracellular Ca2+ mobilization, significantly reduced cell invasion potential and secretion of MMPs in human hepatoma cells (P < 0.05). Importantly, no additive effect between Wortmannin and alpha6beta1 antibodies was observed, indicating that alpha6beta1 and PI3K transmit the signal in an upstream-downstream relationship.

    Conclusion: These results suggest that alpha6beta1 interacts with HAb18G/CD147 to mediate tumor invasion and metastatic processes through the PI3K pathway.

    BMC cancer 2009;9;337

  • A role for p53 in the regulation of extracellular matrix metalloproteinase inducer in human cancer cells.

    Zhu H, Evans B, O'Neill P, Ren X, Xu Z, Hait WN and Yang JM

    Department of Pharmacology and The Penn State Cancer Institute, The Pennsylvania State University College of Medicine, Hershey, PA 17033-0850, USA.

    EMMPRIN, a transmembrane glycoprotein known to promote survival, invasion and metastasis of tumor cells through multiple pathways and mechanisms, has been found to be overexpressed in various types of cancer cells. Here we report that loss of the function of p53, a tumor suppressor protein that is mutated in approximately 50% of human cancers, contributes to the upregulation of EMMPRIN protein. We observed an inverse association between the activity of p53 and the level of EMMPRIN protein in several cancer cell lines. We further demonstrated that p53 is able to negatively regulate EMMPRIN protein, but downregulation of EMMPRIN by p53 is independent of repression of the EMMPRIN transcription. Furthermore, downregulation of EMMPRIN by p53 can be rescued by chloroquine, a lysosome inhibitor, but not by MG132, a proteasome inhibitor, suggesting an involvement of the lysosomal pathway in the p53-regulated degradation of EMMPRIN. Downregulation of EMMPRIN by p53 leads to a decrease in the activity of MMP-9 and an inhibition of tumor cell invasion. Our study suggests that the upregulation of EMMPRIN seen in many cancers can be attributed to, at least in part, the dysfunction of p53 and thus provides new evidence for the roles of p53 in tumor development and progression.

    Funded by: NCI NIH HHS: CA66077, R01 CA066077

    Cancer biology & therapy 2009;8;18;1722-8

  • CD147 expression indicates unfavourable prognosis in prostate cancer.

    Han ZD, Bi XC, Qin WJ, He HC, Dai QS, Zou J, Ye YK, Liang YX, Zeng GH, Chen ZN and Zhong WD

    Guangzhou First Municipal People's Hospital, Affiliated Guangzhou Medical College, #1 Pan Fu Road, Guangzhou 510180, China.

    Extracellular matrix metalloproteinase inducer (EMMPRIN, also named as CD147) is a multifunctional membrane glycoprotein over-expressed in many kinds of human solid tumors. It has been demonstrated to be involved in tumor invasion and angiogenesis. The aim of this study was to analyze the clinicopathological characteristics of the expression of CD147 in human prostate cancer (PCa), and to evaluate its clinical significance in the histologic classification and prognosis of PCa. CD147 protein expression in paraffin-embedded specimens gathered from 62 cases of PCa and 30 cases of benign prostatic hyperplasia (BPH) were detected by the method of immunohistochemistry. The association of CD147 protein expression with the clinicopathological characteristics and with the prognosis of PCa was subsequently assessed. CD147 expression were positively expressed in 51/62 (82.3%) of PCa and 4/30 (13.3%) of BPH cases, respectively. The positive expression rate of CD147 in PCa tissues was significantly higher than that in BPH. The positive expression of CD147 was dramatically associated with TNM grade (p < 0.001), the depth of the prostatic wall invasion (p = 0.008), GLEASON Score (p = 0.001) and Histologic grade (p = 0.001). The patients with CD147 expression were associated with a poor prognosis of PCa (p = 0.01) and the survival rate of the patients with a strong positive expression of CD147 was the lowest (p = 0.01). The results suggest that the expression of CD147 may be an important feature of PCa and the detection of its expression may benefit us in the prediction of the prognosis of PCa.

    Pathology oncology research : POR 2009;15;3;369-74

  • Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in healthy and inflamed human gingival.

    Xiang J, Cao Z, Dong W and Li C

    Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.

    Objective: To evaluate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in healthy and inflamed human gingiva.

    Tissue samples from 9 healthy specimens and 21 specimens with chronic periodontitis were collected. The expression of EMMPRIN protein was detected with immunohistochemical staining and Western blot analysis.

    Results: EMMPRIN was mainly localized in keratinocytes of healthy human gingival tissues; in inflamed gingival tissues, EMMPRIN protein could be detected in keratinocytes, fibroblasts, and inflammatory cells. In addition, EMMPRIN expression level in the inflamed gingiva was increased dramatically compared to that in healthy tissue (P < .05). Using Western blot analysis, EMMPRIN protein was also found to express in both healthy and inflamed gingiva, and the level of EMMPRIN in inflamed gingiva was significantly higher than that in healthy control subjects (P < .05).

    Conclusion: EMMPRIN might be involved in the physiologic and pathologic states of periodontal tissues.

    Quintessence international (Berlin, Germany : 1985) 2009;40;8;683-90

  • Solution characterization of the extracellular region of CD147 and its interaction with its enzyme ligand cyclophilin A.

    Schlegel J, Redzic JS, Porter CC, Yurchenko V, Bukrinsky M, Labeikovsky W, Armstrong GS, Zhang F, Isern NG, DeGregori J, Hodges R and Eisenmesser EZ

    Department of Biochemistry and Molecular Genetics, University of Colorado Denver, School of Medicine, Aurora, CO 80045, USA.

    The CD147 receptor plays an integral role in numerous diseases by stimulating the expression of several protein families and serving as the receptor for extracellular cyclophilins; however, neither CD147 nor its interactions with its cyclophilin ligands have been well characterized in solution. CD147 is a unique protein in that it can function both at the cell membrane and after being released from cells where it continues to retain activity. Thus, the CD147 receptor functions through at least two mechanisms that include both cyclophilin-independent and cyclophilin-dependent modes of action. In regard to CD147 cyclophilin-independent activity, CD147 homophilic interactions are thought to underlie its activity. In regard to CD147 cyclophilin-dependent activity, cyclophilin/CD147 interactions may represent a novel means of signaling since cyclophilins are also peptidyl-prolyl isomerases. However, direct evidence of catalysis has not been shown within the cyclophilin/CD147 complex. In this report, we have characterized the solution behavior of the two most prevalent CD147 extracellular isoforms through biochemical methods that include gel-filtration and native gel analysis as well as directly through multiple NMR methods. All methods indicate that the extracellular immunoglobulin-like domains are monomeric in solution and, thus, suggest that CD147 homophilic interactions in vivo are mediated through other partners. Additionally, using multiple NMR techniques, we have identified and characterized the cyclophilin target site on CD147 and have shown for the first time that CD147 is also a substrate of its primary cyclophilin enzyme ligand, cyclophilin A.

    Funded by: NCI NIH HHS: R01 CA109657, T32 CA082086; NIAID NIH HHS: R01 AI081152-01A1, R21 AI060720, R21 AI060720-01, R21 AI060720-02, R56 AI081152, R56 AI081152-01A1; NIGMS NIH HHS: GM68928

    Journal of molecular biology 2009;391;3;518-35

  • CD147 and VEGF expression in advanced renal cell carcinoma and their prognostic value.

    Liang YX, He HC, Han ZD, Bi XC, Dai QS, Ye YK, Qin WJ, Zeng GH, Zhu G, Xu CL and Zhong WD

    Guangzhou First Municipal People's Hospital, Affiliated Guangzhou Medical College, Guangzhou, China.

    Aim: To investigate the clinicopathologic characteristics of extracellular matrix (ECM) metalloproteinase inducer (CD147) and vascular endothelial growth factor (VEGF) expression in advanced renal cell carcinoma (RCC), and to evaluate the clinical significance of these two markers in the prognosis of advanced RCC.

    Methods: CD147 and VEGF expression in paraffin-embedded specimens gathered from 53 patients with advanced RCC and 12 healthy controls were detected by the method of immunohistochemistry. The Spearman correlation was calculated between the expression levels of CD147 and VEGF in advanced RCC tissues. The association of CD147 and VEGF expression with the clinicopathologic features and prognosis of advanced RCC was subsequently assessed.

    Results: CD147 and VEGF were positively expressed in 47/53 (88.7%) and 45/53 (84.9%) of patients with advanced RCC, respectively. Positive expression of CD147 (p= 0.02) and VEGF (p< 0.01) was significantly correlated with TNM stage of advanced RCC. A significant correlation was found between the expression of CD147 and VEGF in advanced RCC (r= 0.629, p= 0.04). Additionally, tumor CD147 and tumor VEGF expressions were significantly associated with the prognosis of advanced RCC patients. The survival rate of the patients with CD147-/VEGF- expression was the lowest (p< 0.01), and conjoined expressions of CD147-/VEGF- and CD147+/VEGF+ were independent prognostic indicators of advanced RCC (both p< 0.01).

    Conclusion: The expression of CD147 or VEGF may be an important feature of advanced RCC. A combined detection of CD147/VEGF coexpression may benefit us in the prediction of the prognosis of advanced RCC.

    Cancer investigation 2009;27;7;788-93

  • Expression of extracellular matrix metalloproteinase inducer and enhancement of the production of matrix metalloproteinase-1 in tongue squamous cell carcinoma.

    Cao Z, Xiang J and Li C

    Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School & Hospital of Stomatology, Wuhan University, 237 LuoYu Road, Wuhan, People's Republic of China.

    Recent studies have found that in addition to promoting cellular invasion, overexpression of metalloproteinase -1 (MMP-1) is associated with the initial stages of cancer development. Extracellular matrix metalloproteinase inducer (EMMPRIN), a transmembrane glycoprotein, has been reported to be highly expressed in tumor cells and induce production of MMPs from peritumor fibroblasts (PTFs) adjacent to the tumor cells. The expression of EMMPRIN in tongue squamous cell carcinoma (SCC) was investigated in this study. It was found that EMMPRIN was expressed at the cell membrane throughout the entire lesion in tongue SCC. Immunofluorescence staining localized EMMPRIN to the cell membrane in a highly invasive tongue SCC cell line (Tca 8113). EMMPRIN mRNA was expressed at a high level in Tca 8113, whereas MMP-1 mRNA was expressed in PTF but harder to be detected in Tca 8113. Co-culture of Tca 8113 with PTF stimulated production of MMP-1. EMMPRIN was highly expressed in tongue SCC, and could induce local production of MMP-1. These data indicate that EMMPRIN might play an important role in tongue SCC progression and invasion.

    International journal of oral and maxillofacial surgery 2009;38;8;880-5

  • Identification of an active site of EMMPRIN for the augmentation of matrix metalloproteinase-1 and -3 expression in a co-culture of human uterine cervical carcinoma cells and fibroblasts.

    Sato T, Ota T, Watanabe M, Imada K, Nomizu M and Ito A

    Department of Biochemistry and Molecular Biology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. satotak@toyaku.ac.jp

    Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) is highly expressed on malignant tumor cell surface and accelerates tumor invasion. We previously reported that human uterine cervical carcinoma SKG-II cells exhibit the progression of in-vitro invasiveness by utilizing the enhanced production of matrix metalloproteinase (MMP) in human uterine cervical fibroblasts (HUCF) under an in-vitro co-culture model (Sato T et al., Gynecol Oncol 2004; 92:47-56). The aim of this study was to clarify the active site of EMMPRIN in the augmentation of MMP production in the co-culture of SKG-II cells and HUCF.

    Methods: Western and Northern blot analyses were used to examine EMMPRIN and MMP expression in a co-culture of SKG-II cells or EMMPRIN-transfected COS-7 cells and HUCF. A systematic peptide screening method using nine synthetic EMMPRIN peptides was used to identify active site(s) of EMMPRIN for MMP induction.

    Results: SKG-II cells constitutively expressed 53-kDa EMMPRIN on the cell surface and EMMPRIN production was enhanced under the co-culture. The concomitant augmentation of proMMP-3 production was diminished by adding an EMMPRIN antibody. EMMPRIN-transfected COS-7 cells stimulated HUCF to predominantly augment proMMP-1 and -3 expressions. A systematic peptide screening method revealed that (42)SLNDSATEVTGHRWLK(57) in the first loop domain of EMMPRIN participated in the augmentation of proMMP-1 production.

    Conclusions: These results provide a novel mechanism of malignancy of uterine cervical carcinoma, in that the augmentation of EMMPRIN expression by tumor-stromal cell interaction progresses tumor invasion along with the increase of MMP expression via an active site of EMMPRIN, (42)SLNDSATEVTGHRWLK(57).

    Gynecologic oncology 2009;114;2;337-42

  • Defining the human deubiquitinating enzyme interaction landscape.

    Sowa ME, Bennett EJ, Gygi SP and Harper JW

    Department of Pathology, Harvard Medical School, Boston, MA 02115, USA.

    Deubiquitinating enzymes (Dubs) function to remove covalently attached ubiquitin from proteins, thereby controlling substrate activity and/or abundance. For most Dubs, their functions, targets, and regulation are poorly understood. To systematically investigate Dub function, we initiated a global proteomic analysis of Dubs and their associated protein complexes. This was accomplished through the development of a software platform called CompPASS, which uses unbiased metrics to assign confidence measurements to interactions from parallel nonreciprocal proteomic data sets. We identified 774 candidate interacting proteins associated with 75 Dubs. Using Gene Ontology, interactome topology classification, subcellular localization, and functional studies, we link Dubs to diverse processes, including protein turnover, transcription, RNA processing, DNA damage, and endoplasmic reticulum-associated degradation. This work provides the first glimpse into the Dub interaction landscape, places previously unstudied Dubs within putative biological pathways, and identifies previously unknown interactions and protein complexes involved in this increasingly important arm of the ubiquitin-proteasome pathway.

    Funded by: NIA NIH HHS: AG085011, R01 AG011085, R01 AG011085-16; NIDDK NIH HHS: K01 DK098285; NIGMS NIH HHS: GM054137, GM67945, R01 GM054137, R01 GM054137-14, R01 GM067945

    Cell 2009;138;2;389-403

  • EMMPRIN expression in tongue squamous cell carcinoma.

    Huang Z, Huang H, Li H, Chen W and Pan C

    Department of Oral and Maxillfacial Surgery, The Second Affiliated Hospital, Sun Yat-Sen University, Guangdong, China.

    Background: Extracellular matrix metalloproteinase inducer (EMMPRIN) is identified as a tumor-cell membrane protein that stimulates matrix metalloproteinases (MMPs) production. Several studies have shown that higher EMMPRIN expression is associated with shorter survival time and correlated significantly with more advanced clinico-parameters of cancer. The aim of this study was to investigate the relationship between clinico-pathologic characteristics and EMMPRIN, and prognostic significance of EMMPRIN expression in human tongue squamous cell carcinoma.

    Methods: Extracellular MMP inducer expression was examined immunohistochemically on paraffin-embedded tissue specimens from 68 patients with tongue squamous cell carcinoma and who underwent radical surgeries from 1996 to 2006. The 68 patients were followed up from 1 to 119 months, with an average of 27.5 months. Nonparametric tests were performed for the comparison of EMMPRIN expression between two independent groups. Survival analysis was performed to find the prognostic significance of EMMPRIN expression.

    Results: We found that EMMPRIN expression in tongue squamous cell carcinoma is significantly higher than that in non-cancerous epithelium adjacent to carcinoma of tongue. In addition, EMMPRIN expression is significantly associated with tumor diameter and clinical stage in the samples, but did not correlate with gender, age, tumor metastasis, and pathological grade. Finally, survival analysis indicates that EMMPRIN overexpression correlates significantly with poor overall survival in the patient cohort.

    Conclusion: These results suggest that EMMPRIN might represent an attractive target for immunotherapeutic approaches in a subgroup of patients with tongue squamous cell carcinoma.

    Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology 2009;38;6;518-23

  • Upregulation of HAb18G/CD147 in activated human umbilical vein endothelial cells enhances the angiogenesis.

    Chen Y, Zhang H, Gou X, Horikawa Y, Xing J and Chen Z

    Department of Cell Biology and Cell Engineering Research Center and State Key Laboratory of Cancer Biology, Fourth Military Medical University, 17 West Changle Street, Xi'an 710032, China.

    Previous studies demonstrated that CD147 molecule, highly expressed on the surface of various malignant tumor cells, significantly correlated with the malignancy of these cancers; however, the role of HAb18G/CD147 in endothelial cells has yet to be established. In this study, we found that the expression of HAb18G/CD147 was significantly upregulated in activated HUVECs. The inhibition of HAb18G/CD147 expression by specific siRNA led to significantly decreased angiogenesis in vitro. Our data indicate that HAb18G/CD147 may regulate angiogenesis via several mechanisms including proliferation, survival, migration, MMPs secretion, and PI3K/Akt activation. Our findings for the first time suggest that upregulation of HAb18G/CD147 in activated HUVECs might play an important role in angiogenesis.

    Cancer letters 2009;278;1;113-21

  • HAb18G (CD147), a cancer-associated biomarker and its role in cancer detection.

    Li Y, Xu J, Chen L, Chen L, Zhong WD, Zhang Z, Mi L, Zhang Y, Liao CG, Bian HJ, Jiang JL, Yang XM, Li XY, Fan CM, Zhu P, Fu L and Chen ZN

    Cell Engineering Research Centre, Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an, China.

    Aims: To evaluate HAb18G/CD147 as a cancer-associated biomarker using its monoclonal antibody HAb18.

    On immunohistochemical analysis of 28 tissue microarrays and pathological sections of 1117 breast tissue samples, HAb18G/CD147 was expressed in carcinoma with an overall positivity rate of 67.76%, which was significantly higher than that in sarcomas (27.34%, P < 0.0001) and normal epithelial (5.18%, P < 0.0001) and fetal (2.67%, P < 0.0001) tissues. In epithelial tissues from 14 organs, the difference in HAb18G/CD147 expression between normal epithelium and the corresponding carcinoma was also significant (P < 0.05 for each pair). This expression in carcinoma was also found at the mRNA level, suggesting transcriptional level regulation of HAb18G/CD147 expression. In a retrospective study of 106 patients with infiltrating ductal carcinoma of the breast, the level of HAb18G/CD147 expression was positively correlated with tumour recurrence/metastasis (P = 0.0003) and negatively correlated with survival of breast cancer patients (P = 0.002). Multivariable Cox regression analysis showed that HAb18G/CD147 was an independent prognostic factor.

    Conclusions: HAb18G/CD147 is significantly expressed in various cancers and appears to have prognostic significance, rendering it a possible cancer-associated biomarker for pathological diagnosis, prognostic evaluation, targeted therapy and radioimmunoimaging of a broad range of cancer types.

    Histopathology 2009;54;6;677-87

  • HAb18G/CD147 inhibits starvation-induced autophagy in human hepatoma cell SMMC7721 with an involvement of Beclin 1 down-regulation.

    Gou X, Ru Q, Zhang H, Chen Y, Li L, Yang H, Xing J and Chen Z

    Department of Cell Biology & Cell Engineering Research Center & State Key Laboratory of Cancer Biology, The Fourth Military Medical University, Xi'an, 710032.

    HAb18G/CD147, a transmembrane glycoprotein highly expressed in various types of malignant cells, mainly functions as an inducer of matrix metalloproteinases to promote tumor growth, invasion and metastasis. However, whether there are other mechanisms underlying the role of HAb18G/CD147 in tumor progression remains to be elucidated. In this study, we investigated the functional effects of HAb18G/CD147 on autophagy in hepatoma cell line SMMC7721 using immunofluorescence staining, Western blot and transmission electronmicroscopy. Our data showed that specific small interference RNA (siRNA) considerably down-regulated the expression of HAb18G/CD147 in SMMC7721 cells at both messenger RNA (mRNA) and protein levels. The down-regulation of HAb18G/CD147 significantly promoted starvation-induced autophagy in a dose-dependent manner. Using trypan blue exclusion assay, we found that HAb18G/CD147 notably enhanced the survival of SMMC7721 cells through inhibiting starvation-induced autophagy. In addition, we demonstrated that HAb18G/CD147 down-regulated the expression of autophagy-regulating protein Beclin 1 in SMMC7721 cells. Furthermore, our data indicated that HAb18G siRNA-transfected SMMC7721 cells had a significantly decreased level of phosphorylated serine/threonine protein kinase B (pAkt) and the expression of Beclin 1 was inversely associated with the level of pAkt, suggesting that the Class I phosphatidylinositol 3 kinase-Akt pathway may be involved in the down-regulation of Beclin 1 by HAb18G/CD147. Overall, we provide the first experimental evidence to show that HAb18G/CD147 may play an important role in the inhibitory regulation of autophagy. Therefore, our data suggest a new molecular mechanism for HAb18G-mediated hepatoma progression.

    Cancer science 2009;100;5;837-43

  • EMMPRIN (CD147) is a novel receptor for platelet GPVI and mediates platelet rolling via GPVI-EMMPRIN interaction.

    Seizer P, Borst O, Langer HF, Bültmann A, Münch G, Herouy Y, Stellos K, Krämer B, Bigalke B, Büchele B, Bachem MG, Vestweber D, Simmet T, Gawaz M and May AE

    Medizinische Klinik III, Universitätsklinikum Tübingen, Tübingen, Germany.

    The Extracellular Matrix Metalloproteinase Inducer (EMMPRIN, CD147, basigin) is an immunoglobulin-like receptor expressed in various cell types. During cellular interactions homotypic EMMPRIN-EMMPRIN interactions are known to induce the synthesis of matrix metalloproteinases. Recently, we have identified EMMPRIN as a novel receptor on platelets. To our knowledge EMMPRIN has not been shown to serve as adhesion receptor, yet. Here we characterise platelet glycoprotein VI (GPVI) as a novel adhesion receptor for EMMPRIN. Human platelets were prestimulated with ADP and perfused over immobilised recombinant EMMPRIN-Fc or Fc-fragments under arterial shear conditions. ADP-stimulated platelets showed significantly enhanced rolling (but not enhanced firm adhesion) on immobilised EMMPRIN-Fc compared to Fc. Pretreatment of platelets with blocking mAbs anti-EMMPRIN or anti-GPVI leads to a significant reduction of rolling platelets on immobilised EMMPRIN-Fc, whereas pretreatment with blocking mAbs anti-p-selectin, anti-alpha4-integrin or anti-GPIIb/IIIa complex (20 microg/ml each) had no effect. Consistently, chinese hamster ovary (CHO) cells stably transfected with GPVI showed enhanced rolling (but not adhesion) on immobilised EMMPRIN-Fc in comparison to non-transfected CHO cells. Similarly, CHO cells stably transfected with EMMPRIN showed enhanced rolling on immobilised GPVI-Fc (or EMMPRIN-Fc) compared to non transfected CHO-cells. Finally, specific binding of EMMPRIN to GPVI was demonstrated by a modified ELISA and surface plasmon resonance technology with a dissociation constant of 88 nM. Platelet GPVI is a novel receptor for EMMPRIN and can mediate platelet rolling via GPVI-EMMPRIN interaction.

    Thrombosis and haemostasis 2009;101;4;682-6

  • Extracellular matrix metalloproteinase inducer is expressed in the proximal tubular epithelial cells of the human kidney.

    Shimada M, Yamabe H, Osawa H, Nakamura N, Kumasaka R, Murakami R, Fujita T, Osanai T and Okumura K

    Department of Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Japan. omichi@coral.ocn.ne.jp

    Aim: Matrix metalloproteinases (MMP) affect matrix remodelling, and extracellular matrix metalloproteinase inducer (EMMPRIN) has been reported to increase the levels of several MMP. However, the expression of EMMPRIN in the human kidney and its regulatory mechanisms are not well known. In this study, we examined EMMPRIN expression in the human kidney with the biopsied specimens, cultured proximal tubular epithelial cells (PTEC) and human mesangial cells (HMC).

    Methods: EMMPRIN expression was examined by immunofluorescent (IF) study, reverse transcription polymerase chain reaction, western blotting and enzyme-linked immunosorbent assay. We also examined soluble EMMPRIN in the conditioned medium of PTEC stimulated by various agents and its effect in the activities of MMP-2 and MMP-9. Also, IF study in the several kidney diseases was performed to elucidate its role in pathological condition.

    Results: EMMPRIN expression was diffusely observed in the tubular epithelial cells of most patients and healthy adults, but was never observed in glomeruli. Cultured PTEC expressed EMMPRIN, while HMC did not. Soluble EMMPRIN was also detected by enzyme-linked immunosorbent assay in the conditioned medium of PTEC. Epidermal growth factor (50 ng/mL) and phorbol 12-myristate 13-acetate (10(-7) mol/L) stimulated the secretion of soluble EMMPRIN and increased the MMP-2 activity, although these agents did not increase the level of EMMPRIN mRNA. From the IF study, EMMPRIN expression was shown to decrease in tubulointerstitial nephritis.

    Conclusion: EMMPRIN is widely distributed in the tubular epithelial cells of the adult human kidney and may regulate MMP-2 activity via its secretion from PTEC.

    Nephrology (Carlton, Vic.) 2009;14;2;171-8

  • Proteomic identification of differentially expressed plasma membrane proteins in renal cell carcinoma by stable isotope labelling of a von Hippel-Lindau transfectant cell line model.

    Aggelis V, Craven RA, Peng J, Harnden P, Cairns DA, Maher ER, Tonge R, Selby PJ and Banks RE

    Cancer Research UK Clinical Centre, St. James's University Hospital, Leeds, UK.

    The von Hippel-Lindau (VHL) tumour suppressor gene plays a central role in development of clear cell renal cell carcinoma (RCC). Using a cell line pair generated from the VHL-defective RCC cell line UMRC2 by transfection with vector control or VHL (-/+VHL) and stable isotope labelling with amino acids in cell culture (SILAC) followed by enrichment of plasma membrane proteins by cell surface biotinylation/avidin-affinity chromatography and analysis by GeLC-MS/MS, VHL-associated changes in plasma membrane proteins were analysed. Comparative analysis of -/+VHL cells identified 19 differentially expressed proteins which were confirmed by reciprocal SILAC labelling. These included several proteins previously reported to be VHL targets, such as transferrin receptor 1 and the alpha 3 and beta1 integrin subunits and novel findings including upregulation of CD166 and CD147 in VHL-defective cells. Western blotting confirmed these changes and also revealed VHL-dependent alterations in protein form for CD147 and CD166, which in the case of CD166 was shown to be due to differential glycosylation. Analysis of patient-matched normal and malignant renal tissues confirmed these differences were also present in vivo in a subset of clear cell RCCs. These results illustrate the potential of this approach for identifying VHL-dependent proteins that may be important in tumorigenesis.

    Funded by: Cancer Research UK

    Proteomics 2009;9;8;2118-30

  • Hyaluronan, CD44, and emmprin regulate lactate efflux and membrane localization of monocarboxylate transporters in human breast carcinoma cells.

    Slomiany MG, Grass GD, Robertson AD, Yang XY, Maria BL, Beeson C and Toole BP

    Departments of Cell Biology and Anatomy, Medical University of South Carolina, Charleston, South Carolina 29425, USA. slomiamg@musc.edu

    Interactions of hyaluronan with CD44 in tumor cells play important cooperative roles in various aspects of malignancy and drug resistance. Emmprin (CD147; basigin) is a cell surface glycoprotein of the immunoglobulin superfamily that is highly up-regulated in malignant cancer cells and stimulates hyaluronan production, as well as several downstream signaling pathways. Emmprin also interacts with various monocarboxylate transporters (MCT). Malignant cancer cells use the glycolytic pathway and require MCTs to efflux lactate that results from glycolysis. Glycolysis and lactate secretion contribute to malignant cell behaviors and drug resistance in tumor cells. In the present study, we find that perturbation of endogenous hyaluronan, using small hyaluronan oligosaccharides, rapidly inhibits lactate efflux from breast carcinoma cells; down-regulation of emmprin, using emmprin small interfering RNA, also results in decreased efflux. In addition, we find that CD44 coimmunoprecipitates with MCT1, MCT4, and emmprin and colocalizes with these proteins at the plasma membrane. Moreover, after treatment of the cells with hyaluronan oligosaccharides, CD44, MCT1, and MCT4 become localized intracellularly whereas emmprin remains at the cell membrane. Together, these data indicate that constitutive interactions among hyaluronan, CD44, and emmprin contribute to regulation of MCT localization and function in the plasma membrane of breast carcinoma cells.

    Funded by: NCI NIH HHS: R01 CA073839, R01 CA082867

    Cancer research 2009;69;4;1293-301

  • Widespread balancing selection and pathogen-driven selection at blood group antigen genes.

    Fumagalli M, Cagliani R, Pozzoli U, Riva S, Comi GP, Menozzi G, Bresolin N and Sironi M

    Scientific Institute IRCCS E. Medea, Bioinformatic Lab, 23842 Bosisio Parini (LC), Italy.

    Historically, allelic variations in blood group antigen (BGA) genes have been regarded as possible susceptibility factors for infectious diseases. Since host-pathogen interactions are major determinants in evolution, BGAs can be thought of as selection targets. In order to verify this hypothesis, we obtained an estimate of pathogen richness for geographic locations corresponding to 52 populations distributed worldwide; after correction for multiple tests and for variables different from selective forces, significant correlations with pathogen richness were obtained for multiple variants at 11 BGA loci out of 26. In line with this finding, we demonstrate that three BGA genes, namely CD55, CD151, and SLC14A1, have been subjected to balancing selection, a process, rare outside MHC genes, which maintains variability at a locus. Moreover, we identified a gene region immediately upstream the transcription start site of FUT2 which has undergone non-neutral evolution independently from the coding region. Finally, in the case of BSG, we describe the presence of a highly divergent haplotype clade and the possible reasons for its maintenance, including frequency-dependent balancing selection, are discussed. These data indicate that BGAs have been playing a central role in the host-pathogen arms race during human evolutionary history and no other gene category shows similar levels of widespread selection, with the only exception of loci involved in antigen recognition.

    Genome research 2009;19;2;199-212

  • A CD147-targeting siRNA inhibits the proliferation, invasiveness, and VEGF production of human malignant melanoma cells by down-regulating glycolysis.

    Su J, Chen X and Kanekura T

    Department of Dermatology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan.

    Cancer cells require glycolysis for energy; this results in excessive lactate production and secretion. Lactate, the end product of glycolysis, reduces the extracellular pH and contributes to the proliferation, invasiveness, metastasis, and angiogenesis of tumor cells. Our previous results revealed that the over-expressed CD147/basigin plays a critical role in malignant melanoma (MM) invasiveness, metastasis and angiogenesis; CD147 has also been implicated in a specific and strong interaction with monocarboxylate transporters (MCT) 1 and 4 that mediate the transport of lactate. In the present study, we investigated whether CD147/basigin is involved, via its association with MCT1 and 4 to transport lactate, in glycolysis and then contributes to the progression of A375 melanoma cells. A375 cells expressed remarkably higher CD147, MCT1 and 4 and showed increased glycolysis rate compared with normal human melanocytes (NHMC). CD147/basigin co-localized with MCT1 and 4 in the A375 cell membrane. Furthermore, silencing of CD147/basigin in A375 cells by a siRNA clearly abrogated the expression of MCT1 and 4 and their co-localization with CD147/basigin and dramatically decreased the glycolysis rate, extracellular pH, and the production of ATP. Thus, cell proliferation, invasiveness, and VEGF production were significantly decreased by siRNA. These results strongly suggest that highly-expressed CD147 interacts with MCT1 and 4 to promote tumor cell glycolysis, resulting in the progression of MM.

    Cancer letters 2009;273;1;140-7

  • Proteomic analysis reveals Hrs ubiquitin-interacting motif-mediated ubiquitin signaling in multiple cellular processes.

    Pridgeon JW, Webber EA, Sha D, Li L and Chin LS

    Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA.

    Despite the critical importance of protein ubiquitination in the regulation of diverse cellular processes, the molecular mechanisms by which cells recognize and transmit ubiquitin signals remain poorly understood. The endosomal sorting machinery component hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) contains a ubiquitin-interacting motif (UIM), which is believed to bind ubiquitinated membrane cargo proteins and mediate their sorting to the lysosomal degradation pathway. To gain insight into the role of Hrs UIM-mediated ubiquitin signaling in cells, we performed a proteomic screen for Hrs UIM-interacting ubiquitinated proteins in human brain by using an in vitro expression cloning screening approach. We have identified 48 ubiquitinated proteins that are specifically recognized by the UIM domain of Hrs. Among them, 12 are membrane proteins that are likely to be Hrs cargo proteins, and four are membrane protein-associated adaptor proteins whose ubiquitination may act as a signal to target their associated membrane cargo for Hrs-mediated endosomal sorting. Other classes of the identified proteins include components of the vesicular trafficking machinery, cell signaling molecules, proteins associated with the cytoskeleton and cytoskeleton-dependent transport, and enzymes involved in ubiquitination and metabolism, suggesting the involvement of Hrs UIM-mediated ubiquitin signaling in the regulation of multiple cellular processes. We have characterized the ubiquitination of two identified proteins, Munc18-1 and Hsc70, and their interaction with Hrs UIM, and provided functional evidence supporting a role for Hsc70 in the regulation of Hrs-mediated endosome-to-lysosome trafficking.

    Funded by: NIGMS NIH HHS: GM082828, R01 GM082828, R01 GM082828-01A1, R01 GM082828-02, R01 GM082828-02S1; NINDS NIH HHS: NS047575, NS050650, R01 NS047575, R01 NS047575-01, R01 NS047575-02, R01 NS047575-03, R01 NS047575-04, R01 NS050650, R01 NS050650-01A1, R01 NS050650-02, R01 NS050650-03, R01 NS050650-04, T32 NS007480, T32 NS007480-05, T32 NS007480-06, T32 NS007480-07, T32 NS007480-08, T32 NS007480-09, T32NS007480

    The FEBS journal 2009;276;1;118-31

  • Acute lymphoblastic leukemia-derived dendritic cells express tumor associated antigens: PNPT1, PMPCB, RHAMM, BSG and ERCC1.

    Luczynski W, Kowalczuk O, Stasiak-Barmuta A, Ilendo E, Krawczuk-Rybak M and Chyczewski L

    Department of Pediatric Oncology and Hematology, Medical University of Bialystok, Bialystok, Poland. w.luczynski@wp.pl

    In all types of leukemia both in children and adults there is a need for novel therapies that could reduce the risk of relapse after standard treatment. Acute lymphoblastic leukemia (ALL) cells are ineffective antigen presenting cells, but as shown by many authors including results from our laboratory, stimulation with CD40L restores their antigen expressing capacity. The development of T-cell therapies for leukemic patients can be based on discovery of leukemia-associated antigens (LAA) which could be recognized by the host immune system. The aim of our present study was to test the hypothesis that leukemia-derived dendritic cells maintain the expression of tumor associated antigens. Twenty five children with B-cell precursor ALL were prospectively enrolled into the study. The mononuclear cells from peripheral blood or bone marrow were cultured and stimulated (or not) with CD40L and IL-4. The assessment of costimulatory/adhesion molecules with the use of flow cytometry and real-time RT PCR were used to confirm the possibility of turning ALL cells into dendritic-like cells. Additionally 22 tumor associated antigens mRNA levels were determined by real-time PCR technique with the TaqMan chemistry using ready-to-use Low Density Arrays for Gene Expression. The results of the study showed maintained expression and even up-regulation of some (PNPT1, PMPCB, HMMR/RHAMM, BSG and ERCC1) tumor associated antigens in CD40-activated leukemic cells. CD40L stimulation leading to the differentiation of leukemic cells into DCs which combine both antigen presenting function and expression of tumor associated antigens represents an interesting approach in cancer immunotherapy.

    Neoplasma 2009;56;5;428-34

  • Expression of MMP9 and CD147 in invasive squamous cell carcinoma of the uterine cervix and their implication.

    Yu W, Liu J, Xiong X, Ai Y and Wang H

    Department of Microbiology and Pathology, Medical College of Nanchang University, Nanchang 330006, PR China.

    Matrix metalloproteinase 9 (MMP9) and CD147 play a role in invasion and metastasis of many types of human malignancies. The correlation of the expression of MMP9 and CD147 with invasion and metastasis of invasive squamous cell carcinoma (SCC) of the uterine cervix has not been examined. In the present study, RT-PCR assay was used to detect the expression level of MMP9 mRNA semiquantitatively, and immunohistochemical stain was adapted to evaluate the score of CD147 on the cell membrane or in the cytoplasm of tumor cells of 65 cases of invasive squamous cell carcinoma of the uterine cervix and 21 cases of chronic cervitis tissues. MMP9 and CD147 expression in correlation with invasion, metastasis, and differentiation of invasive SCC of the uterine cervix was analyzed statistically. We found that MMP9 and CD147 expression was elevated significantly in tumor tissue compared to the control (cervical epithelium of chronic cervitis) (P<0.01). In the comparison of MMP9 and CD147 expression in 47 cases with lymph node metastasis and 18 cases without lymph node metastasis, there was a significantly higher expression of MMP9 and CD147 in the group with lymph node metastasis (P<0.05 for MMP9, P<0.01 for CD147). MMP9 expression was significantly higher in 24 cases of poor differentiation than in 41 cases of moderate differentiation (P<0.05). No difference was found in CD147 expression between poor and moderate differentiation (P>0.05). No significant difference in MMP9 and CD147 expression levels was obtained between 26 cases of FIGO stage I tumors and 39 cases of stage II tumors (P>0.05 for MMP9, P>0.05 CD147). There was no correlation between MMP9 or CD147 expression levels and the resected tumor size (P>0.05). The positive correlation (r=0.568, P<0.001) of MMP9 expression and CD147 score was seen in the tumor tissues of 65 cases. The data in this study show that MMP9 and CD147 expression are correlated with invasion, metastasis of squamous cell carcinoma of the uterine cervix, and that MMP9 expression is correlated with poor differentiation of invasive squamous cell carcinoma of the uterine cervix.

    Pathology, research and practice 2009;205;10;709-15

  • Prediction of prognosis in gallbladder carcinoma by CD147 and MMP-2 immunohistochemistry.

    Wu W, Wang R, Liu H, Peng J, Huang D, Li B and Ruan J

    Department of Geriatric Surgery, Xiangya Hospital, Central South University, Changsha, 410008, People's Republic of China. wwtw1972@126.com

    Aim: To investigate whether the presence of CD147 and MMP-2 in cancerous gallbladder tissues might help us to predict the patients' prognosis.

    Methods: Tissue samples from 168 patients with gallbladder carcinomas and 37 patients with chronic cholecystitis were stained with anti-CD147 and anti-MMP-2 antibodies for immunohistochemical analysis. Then, the association of their expression with clinicopathologic characteristics and 108 patients' prognosis was analyzed.

    Results: CD147 and MMP-2 were detected mainly in cancerous tissues, but also expressed in some chronic cholecystitis patients. Out of 168 patients with gallbladder carcinoma 121 (72.02%) and 136 (80.95%) patients showed CD147 and MMP-2 positive expression, whereas the 37 patients with chronic cholecystitis only 5 (13.51%) and 3 (8.11%) patients expressed them, respectively. Pathologic findings demonstrated that the intensity of CD147 and MMP-2 staining in cancerous tissues was associated significantly with histological types (P = 0.03), distant metastasis (P < 0.01), and Nevin stages (P = 0.02) of gallbladder carcinomas. Using a proportional hazard model, the survival rate of the patients with CD147+/MMP-2+ expression was the lowest (P < 0.01), and including information on CD147 and MMP-2 staining patterns within cancerous tissues along with clinical cancer staging may improve the accuracy of predicting patients' prognosis.

    Conclusion: The results suggest that the expression of CD147 and MMP-2 may be an important feature of gallbladder carcinomas. The detection of these two markers combined with cancerous staging may increase the ability of investigators to predict the prognosis of patients with gallbladder carcinomas.

    Medical oncology (Northwood, London, England) 2009;26;2;117-23

  • Expression of CD147 mediates tumor cells invasion and multidrug resistance in hepatocellular carcinoma.

    Jia L, Xu H, Zhao Y, Jiang L, Yu J and Zhang J

    Department of Biochemistry, Institute of Glycobiology, Dalian Medical University, Dalian, China.

    Multidrug resistant (MDR) tumor cells over-expressing P-glycoprotein exhibit variation in invasive behavior. To investigate the mechanisms, we analyzed the expression of CD147. The results showed that CD147 expression was increased in HepG2/Adr cells, as compared to HepG2 cells. The MDR cells produced more MMP11 and MDR1, which promoted HepG2/Adr cells invasion and increased resistance to chemotherapeutic drugs. On the other hand, CD147 silencing in HepG2/Adr cells by RNAi led to the opposite effect. Treatment of tumor cells with U-0126, an inhibitor of MAPK/Erk, also down-regulated MMP11 and MDR1 expression. Thus, CD147 may functionally mediate tumor cells invasion and MDR.

    Cancer investigation 2008;26;10;977-83

  • Modulation of tumor cell growth in vivo by extracellular matrix metalloprotease inducer.

    Newman JR, Bohannon IA, Zhang W, Skipper JB, Grizzle WE and Rosenthal EL

    Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Alabama at Birmingham, USA.

    Objective: To investigate if loss of extracellular matrix metalloprotease inducer (EMMPRIN) will inhibit the growth of head and neck squamous cell carcinoma (HNSCC) tumor cell lines in vivo. Tumor cell-derived EMMPRIN is highly overexpressed in HNSCC and is thought to be induced by surrounding fibroblasts to stimulate matrix metalloproteases, which modulate tumor cell invasion, growth, and angiogenesis.

    Design: In vivo study using FaDu tumor xenografts.

    Setting: Academic research facility.

    Subjects: Severe combined immunodeficiency (SCID) mice.

    Interventions: The HNSCC cell line FaDu was transfected with EMMPRIN (FaDu/E), control vector (FaDu), or plasmid-expressing small-interfering RNA against EMMPRIN (FaDu/siE). Tumor cells combined with fibroblast cells were xenografted onto the flank of SCID mice. Tumors were measured biweekly over 4 weeks, at which time the mice were killed, and tumor samples were analyzed for proliferation (Ki-67 immunohistochemical analysis), vascularization (factor VIII staining), and apoptosis (TUNEL [terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling] assay).

    Growth of head and neck cancer cell lines genetically engineered to express variable levels of EMMPRIN.

    Results: Tumor growth positively correlated and animal survival negatively correlated with increasing EMMPRIN expression. FaDu/E tumor growth was significantly larger at 4 weeks compared with FaDu tumors (P = .006). Similarly, the control vector-transfected FaDu tumors were significantly larger than FaDu/siE (P < .001). Immunohistochemical analysis demonstrated increased Ki-67 in EMMPRIN-transfected cells, without a significant change in the rate of apoptosis between groups. Vascular density and tumor formation rate also increased significantly with EMMPRIN expression.

    Conclusion: This study suggests that anti-EMMPRIN-targeted therapy may prove to be a novel treatment option in HNSCC.

    Funded by: NCI NIH HHS: 2T32 CA 091078-06, K08 CA102154-04, K08CA102154, R01 CA142637-02

    Archives of otolaryngology--head & neck surgery 2008;134;11;1218-24

  • Proteome analysis of multidrug resistance of human oral squamous carcinoma cells using CD147 silencing.

    Kuang YH, Chen X, Su J, Wu LS, Li J, Chang J, Qiu Y, Chen ZS and Kanekura T

    Department of Dermatology, Xiang Ya Hospital, Central South University, Hunan, 410008, China, Department of Dermatology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, 890-8520, Japan.

    There is a correlation between the multidrug-resistance (MDR) of cancer cells and their enhanced invasive or metastatic potential. We studied the expression of CD147, a plasma membrane glycoprotein that plays a key role in tumor metastasis by stimulating the production of matrix metalloproteinases (MMPs), in sensitive human oral squamous KB and MDR derivative KB/V cells. Reverse transcription-PCR and flow cytometric analysis revealed that KB/V cells expressed CD147 at significantly higher levels than their parental KB cells. Using stable RNA interference, we succeeded in establishing a CD147 knock-down KB/V cell line (KB/VsiCD147). MTT colorimetric assay showed an increase in the chemosensitivity to vincristine (VCR), all transretinoic acid (ATRA), taxol, and 5-fluorouracil (5-Fu) of KB/VsiCD147 cells. Proteome analysis of KB, KB/V, and KB/VsiCD147 cell lines identified 21 differently expressed proteins. The enhanced expression of representative active proteins, GRP75 and CyPA, was confirmed by Western blotting and RT-PCR. In addition, pretreatment of KB/V cells with a CyPA-binding immunosuppressive drug, cyclosporine A (CsA), enhanced their chemosensitivity to VCR and 5-Fu. We document an abundance of molecules that interact with CD147 in the MDR of human oral squamous carcinoma cells. Additional studies are needed to investigate these novel target proteins of CD147.

    Journal of proteome research 2008;7;11;4784-91

  • Downregulation of CD147 expression alters cytoskeleton architecture and inhibits gelatinase production and SAPK pathway in human hepatocellular carcinoma cells.

    Qian AR, Zhang W, Cao JP, Yang PF, Gao X, Wang Z, Xu HY, Weng YY and Shang P

    Key Laboratory for Space Biosciences & Biotechnology, Institute of Special Environmental Biophysics, Faculty of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, PR China. qianair@nwpu.edu.cn

    Background: CD147 plays a critical role in the invasive and metastatic activity of hepatocellular carcinoma (HCC) cells by stimulating the surrounding fibroblasts to express matrix metalloproteinases (MMPs). Tumor cells adhesion to extracellular matrix (ECM) proteins is the first step to the tumor metastasis. MMPs degrade the ECM to promote tumor metastasis. The aim of this study is to investigate the effects of small interfering RNA (siRNA) against CD147 (si-CD147) on hepatocellular carcinoma cells' (SMMC-7721) architecture and functions.

    Methods: Flow cytometry and western blot assays were employed to detect the transfection efficiency of si-CD147. Confocal microscopy was used to determine the effects of si-CD147 on SMMC-7721 cells' cytoskeleton. Invasion assay, gelatin zymography and cell adhesion assay were employed to investigate the effects of si-CD147 on SMMC-7721 cells' invasion, gelatinase production and cell adhesive abilities. Western blot assay was utilized to detect the effects of si-CD147 on focal adhesion kinase (FAK), vinculiln and mitogen-activated protein kinase (MAPK) expression in SMMC-7721 cells.

    Results: Downregulation of CD147 gene induced the alteration of SMMC-7721 cell cytoskeleton including actin, microtubule and vimentin filaments, and inhibited gelatinase production and expression, cells invasion, FAK and vinculin expression. si-CD147 also blocked SMMC-7721 cells adhesion to collagen IV and phosphorylation level of SAPK/JNKs. SAPK/JNKs inhibitor SP600125 inhibited gelatinase production and expression.

    Conclusion: CD147 is required for normal tumor cell architecture and cell invasion. Downregulation of CD147 affects HCC cell structure and function. Moreover, the alteration of cell behavior may be related to SAPK/JNK Pathway. siRNA against CD147 may be a possible new approach for HCC gene therapy.

    Journal of experimental & clinical cancer research : CR 2008;27;50

  • Cardiac-restricted overexpression of extracellular matrix metalloproteinase inducer causes myocardial remodeling and dysfunction in aging mice.

    Zavadzkas JA, Plyler RA, Bouges S, Koval CN, Rivers WT, Beck CU, Chang EI, Stroud RE, Mukherjee R and Spinale FG

    Medical University of South Carolina, Charleston, South Carolina 29425, USA.

    The matrix metalloproteinases (MMPs) play a pivotal role in adverse left ventricular (LV) myocardial remodeling. The transmembrane protein extracellular MMP inducer (EMMPRIN) causes increased MMP expression in vitro, and elevated levels occur in patients with LV failure. However, the direct consequences of a prolonged increase in the myocardial expression of EMMPRIN in vivo remained unexplored. Cardiac-restricted EMMPRIN expression (EMMPRINexp) was constructed in mice using the full-length human EMMPRIN gene ligated to the myosin heavy chain promoter, which yielded approximately a twofold increase in EMMPRIN compared with that of the age/strain-matched wild-type (WT) mice; EMMPRINexp (n=27) and WT (n=33) mice were examined at 3.2+/-0.1 or at 13.3+/-0.5 mo of age (n=43 and 26, respectively). LV end-diastolic volume (EDV) was similar in young EMMPRINexp and WT mice (54+/-2 vs. 57+/-3 microl), but LV ejection fraction (EF) was reduced (51+/-1 vs. 57+/-1%; P<0.05). In old EMMPRINexp mice, LV EDV was increased compared with WT mice values (76+/-3 vs. 58+/-3 microl; P<0.05) and LV EF was significantly reduced (45+/-1 vs. 57+/-2%; P<0.05). In EMMPRINexp old mice, myocardial MMP-2 and membrane type-1 MMP levels were increased by >50% from WT values (P<0.05) and were accompanied by a twofold higher collagen content (P<0.05). Persistent myocardial EMMPRINexp in aging mice caused increased levels of both soluble and membrane type MMPs, fibrosis, and was associated with adverse LV remodeling. These findings suggest that EMMPRIN is an upstream signaling pathway that can play a mechanistic role in adverse remodeling within the myocardium.

    Funded by: NHLBI NIH HHS: R01 HL059165

    American journal of physiology. Heart and circulatory physiology 2008;295;4;H1394-402

  • The role of extracellular matrix metalloproteinase inducer protein in prostate cancer progression.

    Madigan MC, Kingsley EA, Cozzi PJ, Delprado WJ, Russell PJ and Li Y

    Discipline of Clinical Ophthalmology, Save Sight Institute, University of Sydney, GPO Box 4337, Sydney, NSW 2001, Australia. michele@eye.usyd.edu.au

    Extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) is a multifunctional membrane glycoprotein overexpressed in many solid tumors, and involved in tumor invasion and angiogenesis. We investigated EMMPRIN expression in human prostate cancer (CaP) tissues and cells, and evaluated whether EMMPRIN expression is related to tumor progression and matrix metalloproteinase (MMPs) expression in human CaP. An immunohistochemical study using tissue microarrays of 120 primary CaPs of different grades and 20 matched lymph node metastases from untreated patients was performed. The association of EMMPRIN expression with clinicopathological parameters was evaluated. Co-immunolocalization for EMMPRIN and MMP-1, MMP-2 or MMP-9 in primary tumors was examined using confocal microscopy. Flow cytometry and immunoblotting were used to examine EMMPRIN expression in 11 metastatic CaP cell lines. Heterogeneous expression of EMMPRIN was found in 78/120 (65%) CaPs, correlated significantly with progression parameters including pre-treatment PSA level (P < 0.05) and increased with progression of CaP (Gleason score, P < 0.05; pathological stage, P < 0.01; nodal involvement, P < 0.05 and surgical margin, P < 0.05). Heterogeneous cytoplasmic MMP-1, MMP-2 and MMP-9 associated with EMMPRIN immunolabeling was observed, particularly in tumors with Gleason scores >3 + 4. Metastatic CaP cell lines, except DuCaP, expressed abundant EMMPRIN protein, indicating highly ( approximately 45 to approximately 65 kDa) and less ( approximately 30 kDa) glycosylated forms, although with no relationship to cells being either androgen responsive or nonresponsive. Our results suggest that EMMPRIN may regulate MMPs and be involved in CaP progression, and as such, could provide a target for treating metastatic CaP disease.

    Cancer immunology, immunotherapy : CII 2008;57;9;1367-79

  • CD147 expression as a significant prognostic factor in differentiated thyroid carcinoma.

    Tan H, Ye K, Wang Z and Tang H

    Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.

    CD147 is 1 of the molecules involved in regulating the expression of matrix metalloproteinases (MMPs). The goal of this study was to analyze the expression of CD147 in differentiated thyroid carcinoma (DTC) tissues as well as its association with the clinicopathologic features of DTC patients and its prognostic significance. During our research, CD147 expression in 156 patients who underwent operation for DTC [100 with papillary thyroid carcinoma (PTC) and 56 with follicular thyroid carcinoma (FTC)] were examined by immunostaining on paraffin-embedded tumor specimens. Then, the association of CD147 expression with clinicopathologic characteristics and patients' prognosis was analyzed. As a result, CD147 was expressed in cancerous lesions but not in normal tissues. Overall, 55 of 156 (35.26%) cases showed low CD147-positive expression, 52 of 156 (33.33%) showed intermediate CD147-positive expression, and 49 of 156 (31.41%) showed high CD147-positive expression. Positive CD147 staining was associated significantly with various clinicopathologic features, such as extrathyroidal invasion (P = 0.02), lymph node metastasis (P = 0.01), and depth of tumor invasion (P < 0.01). Patients with low CD147 expression showed better survival rates than those with intermediate and high expression (90.91% for low expression, 82.69% for intermediate expression, and 65.31% in high expression, respectively; P < 0.05 for analyses). Using Cox regression analysis of the 156 patients, high expression of CD147, extrathyroidal invasion, lymph node metastasis, and the pathologic grading of tumor invasion seemed to be independent prognostic indicators (P < 0.01, P = 0.02, P < 0.01, and P < 0.01, respectively). Therefore, we conclude that the expression of CD147 may be useful to predict the prognosis of DTC patients.

    Translational research : the journal of laboratory and clinical medicine 2008;152;3;143-9

  • Cellular localization of EMMPRIN predicts prognosis of patients with operable lung adenocarcinoma independent from MMP-2 and MMP-9.

    Sienel W, Polzer B, Elshawi K, Lindner M, Morresi-Hauf A, Vay C, Eder F, Passlick B and Klein CA

    Department of Thoracic Surgery, University Hospital Freiburg, Freiburg, Germany.

    Extracellular matrix metalloproteinase (MMP) inducer (EMMPRIN, CD147) is a multifunctional protein that has been implicated in cancer invasion and metastasis by the induction of MMPs. To address its role in primary tumors of human non-small-cell lung cancer we assessed whether EMMPRIN expression is associated with the expression of MMP-2 and MMP-9 and with patient survival. Primary tumors of 150 patients (65 adenocarcinomas, 58 squamous cell carcinomas, and 27 of other subtypes) with completely resected lung cancers were stained by immunohistochemistry. We assessed intensity, extent, and cellular localization of EMMPRIN staining and determined MMP-2 and MMP-9 expression. 145 tumors expressed EMMPRIN (strong expression in 61 tumors), which was predominantly localized at the tumor cell membranes in 102 (68%) patients. We could not determine any correlation between EMMPRIN expression and MMP-2 or MMP-9 expression. The prognostic relevance of EMMPRIN was evaluated by Kaplan-Meier and multivariate Cox regression analysis in patients with adenocarcinoma (n=57) and squamous cell carcinoma of the lung (n=56). The median follow-up period was 36.0 months (range 4-156 months). Staining scores for EMMPRIN and MMP-2 and MMP-9 derived from staining intensities and percentages of positive cells did not predict outcome of patients. In contrast, univariate survival analysis demonstrated that membranous localization of EMMPRIN was associated with shortened survival in patients with adenocarcinoma (P=0.03; log-rank test), but not in squamous cell carcinoma. For the former patients, membranous EMMPRIN expression was also an independent predictor of patient survival (P=0.04; Cox regression analysis). The findings point to a role of EMMPRIN for the progression of adenocarcinoma of the lung that is unrelated to its function as inducer of MMPs.

    Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc 2008;21;9;1130-8

  • [EMMPRIN (CD147). A new key protein during tumor progression in bladder cancer].

    Nawroth R, Stöhr R, Hartmann A, Gschwend JE and Retz M

    Urologische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, München, Deutschland. roman.nawroth@lrz.tum.de

    EMMPRIN (CD147) is a cell surface protein that is highly expressed on tumor cells. Elevated EMMPRIN levels have been detected in a variety of malignant tumors and have been associated with tumor progression in experimental and clinical conditions. Recent studies have shown that EMMPRIN is an independent prognostic factor for overall survival in bladder cancer patients. In a multicenter phase II trial, antibodies against EMMPRIN were shown to be successful in hepatocellular cancer therapy. We are characterizing the functional importance of EMMPRIN in bladder cancer in order to evaluate this protein as a new target molecule for therapy.

    Der Urologe. Ausg. A 2008;47;9;1152-6

  • Overexpression of HAb18G/CD147 promotes invasion and metastasis via alpha3beta1 integrin mediated FAK-paxillin and FAK-PI3K-Ca2+ pathways.

    Tang J, Wu YM, Zhao P, Yang XM, Jiang JL and Chen ZN

    Cell Engineering Research Center and Department of Cell Biology, State Key Laboratory of Cancer Biology, State Key Discipline of Cell University, Fourth Military Medical University, Xi'an 710032, PR China.

    Mechanism of HAb18G/CD147 underlying the metastasis process of human hepatoma cells has not been determined. In the present study, we found that integrin alpha3beta1 colocalizes with HAb18G/CD147 in human 7721 hepatoma cells. The enhancing effect of HAb18G/CD147 on adhesion, invasion capacities and matrix metalloproteinases (MMPs) secretion was decreased by integrin alpha3beta1 antibodies (p<0.01). The expressions of integrin downstream molecules including focal adhesion kinase (FAK), phospho-FAK (p-FAK), paxillin, and phospho-paxillin (p-paxillin) were increased in human hepatoma cells overexpressing HAb18G/CD147. Deletion of HAb18G/CD147 reduces the quantity of focal adhesions and rearranges cytoskeleton. Wortmannin and LY294002, specific phosphatidylinositol kinase (PI3K) inhibitors, reversed the effect of HAb18G/CD147 on the regulation of intracellular Ca(2+) mobilization, significantly reducing cell adhesion, invasion and MMPs secretion potential (p<0.01). Together, these results suggest that HAb18G/CD147 enhances the invasion and metastatic potentials of human hepatoma cells via integrin alpha3beta1-mediated FAK-paxillin and FAKPI3K-Ca(2+) signal pathways.

    Cellular and molecular life sciences : CMLS 2008;65;18;2933-42

  • Clinicopathologic evaluation of immunohistochemical CD147 and MMP-2 expression in differentiated thyroid carcinoma.

    Tan H, Ye K, Wang Z and Tang H

    Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.

    Objective: CD147 is one of the molecules involved in regulating the expression of matrix metalloproteinases (MMPs). The goal of this study was to analyze the expression levels of CD147 and MMP-2 in differentiated thyroid carcinomas (DTCs) tissues, as well as their associations with the clinicopathologic features of DTC patients.

    Methods: CD147 and MMP-2 expression in 156 patients who underwent operation for DTC (100 with papillary thyroid carcinomas and 56 with follicular thyroid carcinomas) were examined by immunostaining on paraffin-embedded tumor specimens. The Spearman correlation was calculated between the expression levels of CD147 and MMP-2 in DTC tissues. Then, the association of their expression with clinicopathologic characteristics was analyzed.

    Results: CD147 and MMP-2 were expressed mainly in cancerous lesions, but also expressed in some normal tissues. A total of 55 and 58 in 156 (35.26 and 37.18%, respectively) cases showed low CD147- and MMP-2-positive expression; 52 and 50 in 156 (33.33 and 32.05%, respectively) cases showed intermediate CD147- and MMP-2-positive expression and 49 and 48 in 156 (31.41 and 30.77%, respectively) cases showed high CD147- and MMP-2-positive expression. The Spearman analysis indicated that the expression level of CD147 was positively correlated with that of MMP-2 significantly (rs = 0.86, P = 0.02). Positive CD147 and MMP-2 immunostaining associated significantly with extrathyroidal invasion (P = 0.02, 0.03), lymph node metastasis (P = 0.01, 0.01) and depth of tumor invasion (P < 0.01, =0.01).

    Conclusions: The results have been demonstrated that the expression of CD147 and MMP-2 may be an important feature of DTC. The detection of these two markers may increase the ability of clinicians to investigate the progression of DTC patients.

    Japanese journal of clinical oncology 2008;38;8;528-33

  • Expression of extracellular matrix metalloproteinase inducer in odontogenic cysts.

    Ali MA

    Department of Diagnostic Sciences, Faculty of Dentistry, Kuwait University, Safat, Kuwait. mali@hsc.edu.kw

    Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) is known to induce matrix metalloproteinase (MMP) production. The expression of EMMPRIN in odontogenic cysts has not been previously studied. This study was done to determine the presence and the variability of EMMPRIN expression in various types of odontogenic cysts.

    An immunohistochemical study using a polyclonal anti-EMMPRIN antibody was done using 48 odontogenic cyst cases: 13 odontogenic keratocysts (OKCs), 18 dentigerous cysts (DCs), and 17 periapical cysts (PAs). Twelve cases of normal dental follicles (DFs) were also included in this study for comparison.

    Results: EMMPRIN immunoreactivity was detected in all of the cysts and DFs studied. In odontogenic cysts, EMMPRIN immunoreactivity was generally higher in basal cells than in suprabasal cells. The overall EMMPRIN expression in the epithelial lining of the 3 different types of odontogenic cyst was significantly higher than in the DFs. Overall EMMPRIN expression was also found to be significantly higher in the epithelial lining of OKCs than in the other types of cysts.

    Conclusion: This study confirmed that EMMPRIN is present in odontogenic cysts and DFs. The higher EMMPRIN expression in OKCs suggests that it may be involved in the aggressive behavior of this type of cyst.

    Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 2008;106;2;258-63

  • Inhibition of CD147 gene expression via RNA interference reduces tumor cell proliferation, activation, adhesion, and migration activity in the human Jurkat T-lymphoma cell line.

    Chen X, Su J, Chang J, Kanekura T, Li J, Kuang YH, Peng S, Yang F, Lu H and Zhang JL

    Department of Dermatology, XiangYa Hospital, Central South University, Changsha, Hunan, China. chenxck@yahoo.com

    CD147, a leukocyte surface molecule over-expressed in T-lymphoma cells, is reportedly associated with lymphocyte activation and proteinase production via interactions with fibroblasts and plays a role in stromal invasion by lymphoma cells. To determine the role of CD147 in the progression of T-lymphoma, we performed siRNA interference-mediated knockdown of CD147 in a CD147-expressing Jurkat T-cell line. CD147 knockdown resulted in the decreased proliferation and migration of Jurkat cells and reduced the adhesion of Jurkat cells to extracelluar matrix fibronectin in vitro. CD147-siRNA inhibited the activation of Jurkat cells via down-regulation of CD25 expression. Our results indicate that CD147 is involved in T-lymphoma progression, a finding useful in efforts to develop targeted therapies to treat patients with T-lymphoma.

    Cancer investigation 2008;26;7;689-97

  • Evidence that CD147 modulation of beta-amyloid (Abeta) levels is mediated by extracellular degradation of secreted Abeta.

    Vetrivel KS, Zhang X, Meckler X, Cheng H, Lee S, Gong P, Lopes KO, Chen Y, Iwata N, Yin KJ, Lee JM, Parent AT, Saido TC, Li YM, Sisodia SS and Thinakaran G

    Department of Neurobiology and Neurology, The University of Chicago, Chicago, Illinois 60637, USA.

    Cerebral deposition of beta-amyloid (Abeta) peptides is a pathological hallmark of Alzheimer disease. Intramembranous proteolysis of amyloid precursor protein by a multiprotein gamma-secretase complex generates Abeta. Previously, it was reported that CD147, a glycoprotein that stimulates production of matrix metalloproteinases (MMPs), is a subunit of gamma-secretase and that the levels of secreted Abeta inversely correlate with CD147 expression. Here, we show that the levels and localization of CD147 in fibroblasts, as well as postnatal expression and distribution in brain, are distinct from those of integral gamma-secretase subunits. Notably, we show that although depletion of CD147 increased extracellular Abeta levels in intact cells, membranes isolated from CD147-depleted cells failed to elevate Abeta production in an in vitro gamma-secretase assay. Consistent with an extracellular source that modulates Abeta metabolism, synthetic Abeta was degraded more rapidly in the conditioned medium of cells overexpressing CD147. Moreover, modulation of CD147 expression had no effect on epsilon-site cleavage of amyloid precursor protein and Notch1 receptor. Collectively, our results demonstrate that CD147 modulates Abeta levels not by regulating gamma-secretase activity, but by stimulating extracellular degradation of Abeta. In view of the known function of CD147 in MMP production, we postulate that CD147 expression influences Abeta levels by an indirect mechanism involving MMPs that can degrade extracellular Abeta.

    Funded by: NIA NIH HHS: AG019070, AG021495, AG026660, R01 AG019070, R01 AG021495; NINDS NIH HHS: P01 NS032636, P01 NS032636-139001, R01 NS048283, R01 NS048283-03, R01 NS048283-04

    The Journal of biological chemistry 2008;283;28;19489-98

  • CD147 (extracellular matrix metalloproteinase inducer-emmprin) expression by human articular chondrocytes.

    Orazizadeh M and Salter DM

    Department of Anatomical Sciences, Medical School, Ahwaz Jundishapoor University of Medical Sciences (Ajums), Ahwaz, Iran.

    Background: Integrins are a family of transmembrane proteins that allow communication between the extracellular matrix and the interior of cells. Chondrocytes, cells of articular cartilage, express integrins and these molecules appear to have a variety of roles including mechanotransduction. Integrins are known to associate with a number of accessory molecules such as CD147 that may act to regulate their activity. The purpose of this study was to investigate the expression of CD147 in normal and osteoarthritis human articular cartilage and identify potential roles in mechanical signalling.

    Methods: Expression of CD147 in normal and osteoarthritis human articular cartilage was examined by the immunostaining and Western-blotting techniques. Potential roles in mechanotransduction were studied by assessing effects of function blocking antibodies on the electrophysiological response to mechanical stimulation.

    Results: CD147 was extensively expressed by chondrocytes in normal and osteoarthritic cartilage and shown by Western-blotting to have a molecular weight in the region of 35-50 kDa. Function blocking antibodies had no effect on the membrane depolarisation response of chondrocytes from osteoarthritic cartilage to mechanical stimulation.

    Conclusion: Human articular chondrocytes show extensive expression of CD147 in normal and osteoarthritic cartilage. Roles for this molecule in regulation of chondrocyte function remain to be defined.

    Iranian biomedical journal 2008;12;3;153-8

  • EMMPRIN modulates migration and deposition of TN-C in oral squamous carcinoma.

    Dang D, Atakilit A and Ramos DM

    Department of Orofacial Sciences, University of California at San Francisco, San Francisco, CA 94143-0512, USA.

    The extracellular matrix metalloproteinase inducer (EMMPRIN), found on the surface of many tumor cells, stimulates the production of matrix metalloproteinases (MMPs) by both fibroblasts and the tumor cells themselves. To evaluate its possible role as a tumor promoter, we first overexpressed EMMPRIN, by retroviral transduction, into poorly invasive squamous cell carcinoma (SCC) cells. Secondly, we knocked down its expression using small interfering RNA (siRNA) in invasive SCC cells. The cell lines were then re-evaluated for migration on fibronectin (FN). Overexpression of EMMPRIN, promoted motility, whereas the siRNA decreased migration. The MMP expression by these variant SCC cell lines was also manipulated by EMMPRIN. The expression of MMP-2, -3, and -9 coincided with the expression of EMMPRIN. Cocultures of SCC/peritumor fibroblasts (PTF) were used to investigate tenascin-C (TN-C) matrix deposition. The cocultures overexpressing EMMPRIN, deposited several fold greater levels of TN-C compared to the control cocultures. In addition, the siRNA cocultures deposited minimal amounts of TN-C. In the presence of the broad spectrum MMP inhibitor, GM6001, TN-C deposition by the EMMPRIN overexpressing cocultures was suppressed. Thus EMMPRIN regulates migration, MMP production by SCC cells and deposition of the TN-C matrix.

    Funded by: NIDCR NIH HHS: P01DE13904, R01 DE11930, R01 DE12856

    Anticancer research 2008;28;4B;2049-54

  • Basigin-2 is a cell surface receptor for soluble basigin ligand.

    Belton RJ, Chen L, Mesquita FS and Nowak RA

    Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. rbelton@uiuc.edu

    The metastatic spread of a tumor is dependent upon the ability of the tumor to stimulate surrounding stromal cells to express enzymes required for tissue remodeling. The immunoglobulin superfamily protein basigin (EMMPRIN/CD147) is a cell surface glycoprotein expressed by tumor cells that stimulates matrix metalloproteinase and vascular endothelial growth factor expression in stromal cells. The ability of basigin to stimulate expression of molecules involved in tissue remodeling and angiogenesis makes basigin a potential target for the development of strategies to block metastasis. However, the identity of the cell surface receptor for basigin remains controversial. The goal of this study was to determine the identity of the receptor for basigin. Using a novel recombinant basigin protein (rBSG) corresponding to the extracellular domain of basigin, it was demonstrated that the native, nonglycosylated rBSG protein forms dimers in solution. Furthermore, rBSG binds to the surface of uterine fibroblasts, activates the ERK1/2 signaling pathway, and induces expression of matrix metalloproteinases 1, 2, and 3. Proteins that interact with rBSG were isolated using a biotin label transfer technique and sequenced by matrix-assisted laser desorption ionization tandem mass spectrophotometry. The results demonstrate that rBSG interacts with basigin expressed on the surface of fibroblasts and is subsequently internalized. During internalization, rBSG associates with a novel form of human basigin (basigin-3). It was concluded that cell surface basigin functions as a membrane receptor for soluble basigin and this homophilic interaction is not dependent upon glycosylation of the basigin ligand.

    Funded by: NICHD NIH HHS: U54 HD 40093

    The Journal of biological chemistry 2008;283;26;17805-14

  • Crystal structure of HAb18G/CD147: implications for immunoglobulin superfamily homophilic adhesion.

    Yu XL, Hu T, Du JM, Ding JP, Yang XM, Zhang J, Yang B, Shen X, Zhang Z, Zhong WD, Wen N, Jiang H, Zhu P and Chen ZN

    Cell Engineering Research Center & Department of Cell Biology, State Key Laboratory of Cancer Biology, Xijing Hospital, the Fourth Military Medical University, Xi'an, China.

    CD147, a member of the immunoglobulin superfamily (IgSF), plays fundamental roles in intercellular interactions in numerous pathological and physiological processes. Importantly, our previous studies have demonstrated that HAb18G/CD147 is a novel hepatocellular carcinoma (HCC)-associated antigen, and HAb18G/CD147 stimulates adjacent fibroblasts and HCC cells to produce elevated levels of several matrix metalloproteinases, facilitating invasion and metastasis of HCC cells. In addition, HAb18G/CD147 has also been shown to be a novel universal cancer biomarker for diagnosis and prognostic assessment of a wide range of cancers. However, the structural basis underlying the multifunctional character of CD147 remains unresolved. We report here the crystal structure of the extracellular portion of HAb18G/CD147 at 2.8A resolution. The structure comprises an N-terminal IgC2 domain and a C-terminal IgI domain, which are connected by a 5-residue flexible linker. This unique C2-I domain organization is distinct from those of other IgSF members. Four homophilic dimers exist in the crystal and adopt C2-C2 and C2-I dimerization rather than V-V dimerization commonly found in other IgSF members. This type of homophilic association thus presents a novel model for homophilic interaction between C2 domains of IgSF members. Moreover, the crystal structure of HAb18G/CD147 provides a good structural explanation for the established multifunction of CD147 mediated by homo/hetero-oligomerizations and should represent a general architecture of other CD147 family members.

    The Journal of biological chemistry 2008;283;26;18056-65

  • Host CD147 blockade by small interfering RNAs suppresses growth of human colon cancer xenografts.

    Abraham D, Zins K, Sioud M, Lucas T and Aharinejad S

    Laboratory for Cardiovascular Research, Center of Anatomy and Cell Biology, Medical University of Vienna, Waehringerstrasse 13, A-1090 Vienna, Austria.

    Tumor cells can stimulate matrix metalloproteinase (MMP) production by stromal cells through cell-cell interactions mediated by cell adhesion molecules such as extracellular matrix metalloproteinase inducer (human CD147/EMMPRIN, mouse CD147/Basigin). This study sought to characterize whether specific tumor-stromal cell interactions mediated by CD147 promote colon cancer growth by utilizing small interfering (si)RNAs directed against human CD147/EMMPRIN or mouse CD147/Basigin in co-cultures of cancer cells with macrophages and fibroblasts and established human SW620 colon cancer xenograft models in immune deficient mice. We show that blockade of host (mouse) CD147/Basigin expression, but not cancer cell-derived CD147/EMMPRIN, suppresses tumor growth in human colon cancer xenografts. Experiments in vitro indicated that colon cancer cell-stromal cell interactions mediated by CD147 lead to increased MMP-2 expression in fibroblasts but not macrophages. Furthermore, expression of host VEGF-A in both fibroblasts and macrophages is independent of CD147 in vitro and in vivo. Interestingly, inhibition of cancer cell-derived EMMPRIN leads to increased MMP-9 levels in vivo. Our findings provide new insights into CD147-mediated tumor-host interactions mediating colon cancer growth.

    Frontiers in bioscience : a journal and virtual library 2008;13;5571-9

  • Extracellular matrix metalloproteinase inducer/CD147 promotes myofibroblast differentiation by inducing alpha-smooth muscle actin expression and collagen gel contraction: implications in tissue remodeling.

    Huet E, Vallée B, Szul D, Verrecchia F, Mourah S, Jester JV, Hoang-Xuan T, Menashi S and Gabison EE

    CRRET Laboratory, CNRS UMR 7149, University Paris XII, 61 Av du Général de Gaulle, 94010 Créteil Cedex, France.

    Extracellular matrix metalloproteinase inducer (EMMPRIN) is a cell surface glycoprotein enriched on tumor cells and normal epithelia. It is mainly known for its ability to induce matrix metalloproteinase production in fibroblasts following epithelial-stromal interaction. We sought to examine whether EMMPRIN has a broader role promoting fibroblast-to-myofibroblast differentiation. Because alpha-smooth muscle actin (alphaSMA) is considered a marker of this differentiation process, we analyzed the effect of EMMPRIN on its expression in corneal and skin fibroblasts by Western blots, immunocytochemistry, and a functional assay of collagen lattice contraction. Increasing EMMPRIN expression by cDNA transfection or by treatment with exogenously added recombinant EMMPRIN resulted in an up-regulation of alphaSMA expression. EMMPRIN also increased the contractile properties of the treated fibroblasts as demonstrated by the immunohistochemical appearance of stress fibers and by the accelerated contraction of fibroblast-embedded collagen lattices. Blocking EMMPRIN expression by small interfering RNA inhibited alphaSMA and collagen gel contraction induced not only by EMMPRIN but also by transforming growth factor-beta, a major mediator of myofibroblast differentiation that also regulated EMMPRIN expression. These findings, combined with the fact that EMMPRIN and alphaSMA colocalized to the same cells in the stroma of pathological corneas, expand on the mechanism by which EMMPRIN remodels extracellular matrix during wound healing and cancer.

    FASEB journal : official publication of the Federation of American Societies for Experimental Biology 2008;22;4;1144-54

  • LFA-1-mediated leukocyte adhesion regulated by interaction of CD43 with LFA-1 and CD147.

    Khunkaewla P, Schiller HB, Paster W, Leksa V, Cermák L, Andera L, Horejsí V and Stockinger H

    Department of Molecular Immunology, Center for Physiology, Pathophysiology & Immunology, Medical University of Vienna, Vienna, Austria.

    The activity of the lymphocyte-function associated antigen 1 (LFA-1; CD11a/CD18) must be tightly controlled during the onset of cellular immunity. It is well known that the sialoglycoprotein CD43 can influence LFA-1-mediated cell adhesion in an either anti- or pro-adhesive manner through mechanisms not well understood. By using a yeast-2-hybrid screen and co-immunoprecipitation we identified physical association of CD43 with two novel partners, LFA-1 itself and the Ig-family member CD147 (EMMPRIN, basigin), and characterized how these interactions are involved in LFA-1-mediated cell adhesion. Monoclonal antibodies (mAbs) to both CD43 and CD147 induced similar homotypic cell aggregation and adhesion of Jurkat T cells and U937 myeloid cells. Both CD43 and CD147 mAbs induced dynamic co-capping of LFA-1 together with the CD43 and the CD147 molecule to cell contact zones. However, in contrast to CD43, we were not able to co-immunoprecipitate LFA-1 with CD147, which indicates that CD43 interacts with CD147 and LFA-1 in two distinct but similarly reorganized complexes. Co-transfection of CD43 interfered with the CD147-induced cell adhesion and aggregation, and siRNA-mediated knock down of CD43 in human T cells resulted in enhanced LFA-1 activation induced via CD147 and also the T cell antigen receptor. These results indicate that triggering CD43 and the underlying signaling pathways enhance LFA-1 adhesiveness while CD43 also negatively regulates LFA-1 induction via other receptors by dynamic interaction with either LFA-1 or CD147.

    Molecular immunology 2008;45;6;1703-11

  • CD147 inhibits the nuclear factor of activated T-cells by impairing Vav1 and Rac1 downstream signaling.

    Ruiz S, Castro-Castro A and Bustelo XR

    Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas-University of Salamanca, Campus Unamuno, E-37007 Salamanca, Spain.

    CD147 is a transmembrane protein that plays crucial roles in the development and function of the reproductive, visual, and nervous systems. CD147 also exerts positive and negative actions in T-cells by still obscure mechanisms. In this study, we have analyzed the expression, localization, and function of CD147 during T-cell receptor signaling responses. We show here that CD147 is an integral component of the T-cell immune synapse and that its overexpression leads to the inhibition of NF-AT (nuclear factor of activated T-cells) activity induced by Vav1, a Rac1 exchange factor. This inhibitory activity is mediated by the CD147 intracellular tail and is totally independent of its extracellular or transmembrane regions. The molecular dissection of the influence of CD147 on the Vav1 pathway indicates that its inhibitory action takes place downstream of Vav1 and Rac1 but upstream of the serine/threonine kinases JNK and Pak1. The interference of CD147 with these pathways is highly specific because the overexpression of CD147 does not affect the activity of other GDP/GTP exchange factors or the stimulation of the ERK cascade. Finally, we show that the CD147 knockdown in Jurkat cells promotes higher levels of NF-AT stimulation and Pak1 phosphorylation upon T-cell receptor cross-linking. Instead, the lack of CD147 does not affect other signaling cascades that participate in the same cellular response. Taken together, these results indicate that CD147, via the selective inhibition of specific downstream elements of the Vav1/Rac1 route, contributes to the negative regulation of T-cell responses.

    Funded by: NCI NIH HHS: 5R01-CA73735-11

    The Journal of biological chemistry 2008;283;9;5554-66

  • A role for membrane-bound CD147 in NOD2-mediated recognition of bacterial cytoinvasion.

    Till A, Rosenstiel P, Bräutigam K, Sina C, Jacobs G, Oberg HH, Seegert D, Chakraborty T and Schreiber S

    Institute for Clinical Molecular Biology, University Hospital Schleswig-Holstein, Campus Kiel, Schittenhelmstr 12, Kiel, Germany.

    NOD2 is an intracellular receptor for the bacterial cell wall component muramyl dipeptide. Mutations in the leucine-rich repeat region of NOD2, which lead to an impaired recognition of muramyl dipeptide, have been associated with chronic inflammatory diseases of barrier organs such as Crohn disease, asthma and atopic eczema. In this study we identify CD147 (also known as BSG and EMMPRIN), a membrane-bound regulator of cellular migration, differentiation and inflammatory processes, as a protein interaction partner of NOD2. We demonstrate a complex influence of the CD147-NOD2 interaction on NOD2-dependent signaling responses. We show that CD147 itself acts as an enhancer of the invasion of Listeria monocytogenes, an intracellular bacterial pathogen. We propose that the CD147-NOD2 interaction serves as a molecular guide to regulate NOD2 function at sites of pathogen invasion.

    Journal of cell science 2008;121;Pt 4;487-95

  • Extracellular matrix metalloproteinase inducer (CD147) is a novel receptor on platelets, activates platelets, and augments nuclear factor kappaB-dependent inflammation in monocytes.

    Schmidt R, Bültmann A, Fischel S, Gillitzer A, Cullen P, Walch A, Jost P, Ungerer M, Tolley ND, Lindemann S, Gawaz M, Schömig A and May AE

    Deutsches Herzzentrum und I. Medizinische Klinik, Klinikum rechts der Isar, Technische Universität München, Lazarettstr. 36, 80636 München, Germany. schmidtr@dhm.mhn.de

    In atherosclerosis, circulating platelets interact with endothelial cells and monocytes, leading to cell activation and enhanced recruitment of leukocytes into the vascular wall. The invasion of monocytes is accompanied by overexpression of matrix metalloproteinases (MMPs), which are thought to promote atherosclerosis and trigger plaque rupture. Following interaction with itself, the extracellular matrix metalloproteinase inducer (EMMPRIN) induces MMP synthesis via a little-known intracellular pathway. Recently, we showed upregulation of EMMPRIN on monocytes during acute myocardial infarction. EMMPRIN also stimulates secretion of MMP-9 by monocytes and of MMP-2 by smooth muscle cells, indicating that it may be an important regulator of MMP activity. Expression of EMMPRIN on platelets has not been described until now. Here, we demonstrate that resting platelets show low surface expression of EMMPRIN, which is upregulated by various platelet stimulators (flow cytometry). EMMPRIN is located in the open canalicular system and in alpha granules of platelets (according to electron microscopy and sucrose gradient ultracentrifugation). Platelet stimulation with recombinant EMMPRIN-Fc induced surface expression of CD40L and P-selectin (according to flow cytometry), suggesting that EMMPRIN-EMMPRIN interaction activates platelets. Coincubation of platelets with monocytes induced EMMPRIN-mediated nuclear factor kappaB activation (according to Western blot) in monocytes with increased MMP-9 (zymography), interleukin-6, and tumor necrosis factor-alpha secretion (according to ELISA) by monocytes. In conclusion, EMMPRIN displays a new platelet receptor that is upregulated on activated platelets. Binding of EMMPRIN to platelets fosters platelet degranulation. Platelet-monocyte interactions via EMMPRIN stimulate nuclear factor kappaB-driven inflammatory pathways in monocytes, such as MMP and cytokine induction. Thus, EMMPRIN may represent a novel target to diminish the burden of protease activity and inflammation in atherosclerosis.

    Circulation research 2008;102;3;302-9

  • EMMPRIN expression as a prognostic factor in radiotherapy of cervical cancer.

    Ju XZ, Yang JM, Zhou XY, Li ZT and Wu XH

    Department of Gynecologic Oncology, The Cancer Hospital of Fudan University, Shanghai, China.

    Purpose: Overexpression of extracellular matrix metalloproteinase inducer (EMMPRIN), a member of the immunoglobulin family and a glycoprotein enriched on the surface of many types of tumor cells, has been reported to be linked to invasion, metastasis, growth, and survival of malignant cells. Cervical cancer, the second most prevalent cancer in women worldwide and the fifth leading cause of cancer deaths, responds to radiotherapy variably, with 30% of cases recurring after therapy. The purpose of this study was to determine whether expression of EMMPRIN affects the response of cervical cancer to radiation therapy, and whether this membrane protein can be used as a prognostic marker for cervical cancer.

    The retrospective cohort study included 82 patients with invasive cervical cancer referred to the Department of Gynecologic Oncology at The Cancer Hospital of Fudan University (Shanghai) between 1991 and 2000. These patients were treated with brachytherapy at a dose of 15 Gy at point A before radical hysterectomy. Expression of EMMPRIN in cervical tumor specimens was examined by immunohistochemistry staining before and after brachytherapy and scored for both staining intensity and percentage of tumor cells stained. EMMPRIN immunoreactivity and clinicopathologic data were analyzed with respect to survival end points using univariate and multivariate approaches.

    Results: The frequency of EMMPRIN overexpression was 52.4% in primary cervical cancer. After brachytherapy, EMMPRIN overexpression was significantly reduced (13.4%) compared with corresponding tumor before brachytherapy (P = 0.032). EMMPRIN expression was associated with pelvic lymph node metastasis (P = 0.026) and reduction in primary tumor volume following brachytherapy (P = 0.008). Although EMMPRIN expression before or after brachytherapy did not correlate with tumor-specific survival, but increased expression of EMMPRIN following brachytherapy tended to predict poor outcomes by univariate survival analysis (P = 0.0008). In addition, lymph vascular space invasion, deep stromal invasion, and lymph node metastasis were significantly associated with poor prognosis. In multivariate analysis, the independent prognostic factors for tumor-specific survival included the decreased expression of EMMPRIN after brachytherapy (P = 0.002; hazard ratio, 0.339; 95% confidence interval, 0.172-0.672) as well as lymph node metastasis (P = 0.044; hazard ratio, 2.053; 95% confidence interval, 1.020-4.133).

    Conclusion: Expression of EMMPRIN was associated with a decrease in the reduction of cervical tumor following brachytherapy, and increased EMMPRIN expression after brachytherapy seemed to be an important predictor of poor survival in this patient cohort. Our study suggests that expression of EMMPRIN confers resistance to radiotherapy. Therefore, EMMPRIN expression in cervical cancer may be regarded both as a prognostic factor and a therapeutic target.

    Clinical cancer research : an official journal of the American Association for Cancer Research 2008;14;2;494-501

  • CD147, MMP-1, MMP-2 and MMP-9 protein expression as significant prognostic factors in human prostate cancer.

    Zhong WD, Han ZD, He HC, Bi XC, Dai QS, Zhu G, Ye YK, Liang YX, Qin WJ, Zhang Z, Zeng GH and Chen ZN

    Guangzhou First Municipal People's Hospital, Affiliated Guangzhou Medical College, Guangzhou, China. wdezhong@21cn.com

    Aim: CD147 and MMPs have been demonstrated to be involved in tumor invasion and angiogenesis. The aim of this study was to analyze the clinicopathological significance of CD147, MMP-1, MMP-2 and MMP-9 expression in human prostate cancer (PCa) and to evaluate their involvement in the progression of PCa.

    Methods: CD147, MMP-1, MMP-2 and MMP-9 expression was assessed in paraffin-embedded specimens collected from 62 cases of PCa and 15 cases of benign prostatic hyperplasia (BPH) by immunohistochemistry. Spearman's correlation was applied to determine possible relationships between CD147, MMP-1, MMP-2 and MMP-9 expression and PCa. The association of CD147 and MMP-2 protein expression with the clinicopathological characteristics and the prognosis of PCa was subsequently assessed.

    Results: CD147was expressed in 51/62 (82.3%) PCa patients and in 2/15 (13.3%) BPH cases. MMP-1, MMP-2 and MMP-9 expression was significantly higher in PCa tissue than in BPH tissue. Using Spearman analysis, a significant positive correlation between CD147 and MMP-1, MMP-2 and MMP-9 expression was found (p <0.05). CD147 and MMP-2 expression was correlated with TMN grade and Gleason score. Patients with concurrent expression of CD147+ and MMP-2+ had the lowest survival (p <0.01).

    Conclusion: The results suggest that concurrent expression of CD147 and MMP may be an important characteristic of PCa which may help in the prediction of PCa progression.

    Oncology 2008;75;3-4;230-6

  • Interaction between CD147 and P-glycoprotein and their regulation by ubiquitination in breast cancer cells.

    Wang WJ, Li QQ, Xu JD, Cao XX, Li HX, Tang F, Chen Q, Yang JM, Xu ZD and Liu XP

    Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China.

    Background: Multidrug-resistant cancer cells overexpressing P-glycoprotein (P-gp) display variations in invasive and metastatic ability through the upregulation of the extracellular matrix metalloproteinase (MMP) inducer (CD147). However, the direct linkage between these two proteins is still unclear.

    Methods: We used immunoprecipitation, immunofluorescence analysis, migration and invasion assays, drug sensitivity assay and Western blot to measure the physical and functional interaction between P-gp and CD147. Then we transfected vectors carrying ubiquitin C-terminal hydrolase L1 (UCH-L1) or UCH-L1 siRNA into MCF7 and MCF7/Adr cells, respectively, and investigated the role of UCH-L1 in the regulation of the expression and degradation of P-gp, CD147 and MMP-1, MMP-2, and MMP-9 by quantitative real-time polymerase chain reaction, Western blot and immunoprecipitation.

    Results: In this paper, we showed that P-gp and CD147 interacted with each other, and that the ubiquitin-proteasome pathway played an important role in the turnover of them. In addition, we found that inhibition of N-glycosylation increased the ubiquitination and degradation of P-gp and CD147, and affected their function. UCH-L1 not only regulated the expression of P-gp, CD147 and MMP-1, MMP-2, and MMP-9, but also the ubiquitination and degradation of P-gp and CD147 in breast cancer cells.

    Conclusion: Our results demonstrate a mechanism underlying the linkage between multidrug resistance and tumor metastasis, and suggest for the first time that modulating the ubiquitination of P-gp and CD147 might be a novel method for tumor therapy.

    Chemotherapy 2008;54;4;291-301

  • Soluble EMMPRIN (extra-cellular matrix metalloproteinase inducer) stimulates the migration of HEp-2 human laryngeal carcinoma cells, accompanied by increased MMP-2 production in fibroblasts.

    Hanata K, Yamaguchi N, Yoshikawa K, Mezaki Y, Miura M, Suzuki S, Senoo H and Ishikawa K

    Department of Otolaryngology, Akita University School of Medicine, Akita, Japan. hanata@med.akita-u.ac.jp

    The basement membrane functions as a barrier against the invasion of cancer cells. It is therefore important to investigate the mechanism of basement membrane degradation by matrix metalloproteinases (MMPs). Previously, cancer cells were long considered to be the major source of MMPs; however, current evidence indicates that most MMPs in cancer tissue are produced by stromal rather than cancer cells. A glycoprotein highly expressed on the cancer-cell membrane, EMMPRIN (extra-cellular matrix metalloproteinase inducer), exhibits the potential role of the MMP inductor in stromal cells. Depending on the cell type, EMMPRIN can stimulate the production of MMP-1, MMP-2, and MMP-3. We here report that soluble full-length EMMPRIN is liberated from HEp-2 human laryngeal epidermoid carcinoma cells, probably via microvesicle shedding. Soluble EMMPRIN stimulates human fibroblasts to produce MMP-2, after which the augmented migration of HEp-2 cells occurs, as observed in an invasion chamber assay with separately cultured fibroblasts. An anti-EMMPRIN function-blocking antibody reduced MMP-2 activity in the conditioned medium and inhibited the migration of HEp-2; obviously, EMMPRIN activity contributes to cancer-cell migration. We postulate that soluble EMMPRIN probably triggers the promotion of cancer invasion in vivo.

    Archives of histology and cytology 2007;70;5;267-77

  • Up-regulation of CD147 and matrix metalloproteinase-2, -9 induced by P-glycoprotein substrates in multidrug resistant breast cancer cells.

    Li QQ, Wang WJ, Xu JD, Cao XX, Chen Q, Yang JM and Xu ZD

    Department of Pathology, Shanghai Medical College, Fudan University, No. 138, Yixueyuan Road, Shanghai 200032, China.

    Treatment of animals bearing multidrug resistant (MDR) tumor cells with P-glycoprotein (P-gp) substrates could worsen host survival. It is assumed that this is due to increased tumor metastasis. To clarify the mechanism(s) underlying this observation, the MDR human breast cancer cell line, MCF-7/AdrR, and its sensitive parental line, MCF-7, was treated with various concentrations of P-gp substrate drugs (vincristine, paclitoxel, adriamycin) and a P-gp non-substrate drug (bleomycin) in serum-free media. Increased production of CD147, and matrix metalloproteinases (MMP)-2, -9 was observed only in MDR cancer cells exposed to P-gp substrates, as determined using real-time polymerase chain reaction, western blotting and zymography. Correspondingly, P-gp substrates significantly enhanced the in vitro invasion abilities of MCF-7/Adr cells. It was also found that the drug-induced promotion of CD147, and MMP-2, -9 was consistent with increased expression of epidermal growth factor receptor (EGFR) and that inhibition of either EGFR or P-gp activity could significantly interrupt the downstream effects, and so inhibit in vitro invasion abilities motivated by P-gp substrates. These results imply that treatment of MDR tumors with P-gp substrates could adversely affect therapeutic outcomes through modulating the production of CD147, MMP-2, -9, and EGFR, and suggest that this effect may be initiated by the transporter function of P-gp.

    Funded by: NCI NIH HHS: CA 66077, CA109371

    Cancer science 2007;98;11;1767-74

  • [Expression of matrix metalloproteinase (MMP-2) and extracellular matrix metalloproteinases inducer (EMMPRIN) in benign and advanced breast cancer tissue samples].

    Chandru H, Sharada AC and Manjunath S

    Tumor cell derived matrix metalloproteinases are a family of enzymes associated with the tumor invasion and metastasis. Extracellular matrix metalloproteinases inducer (EMMPRIN) stimulates synthesis of gelatinase A (MMP-2) in peritoneal fibroblasts. In the present study the role of MMP-2 and EMMPRIN in the progression of breast cancer has been investigated. Gelatinase-A and EMMPRIN were analyzed in benign and stage II and stage III breast cancer tissue samples by gelatin zymography assay, immunoprecipation analysis and Western blot analysis with a monoclonal primary antibody specific for EMMPRIN. Our results showed overexpression of EMMPRIN in advanced stages of breast cancer tissues compared with benign tumor tissue samples. The expression of MMP-2, the active and latent forms of the enzyme increased with tumor progression from Stage II to Stage III of breast cancer and it was not expressed in benign tissues. The expression MMP-2 correlates with tumor progression. This observation obviously indicates that EMMPRIN and MMP-2 are the major determinants of malignancy in cancers.

    Biomeditsinskaia khimiia 2007;53;4;461-7

  • Involvement of CD147 in regulation of multidrug resistance to P-gp substrate drugs and in vitro invasion in breast cancer cells.

    Li QQ, Wang WJ, Xu JD, Cao XX, Chen Q, Yang JM and Xu ZD

    Department of Pathology, Shanghai Medical College, Fudan University, Shanghai 200032, China.

    Multidrug resistant (MDR) cancer cells overexpressing P-glycoprotein (P-gp) display variations in invasive and metastatic behavior. We aimed to clarify the mechanism(s) underlying this observation and transfected vectors carrying CD147, a glycoprotein enriched on the surface of tumor cells that stimulates the production of matrix metalloproteinases (MMPs), and specific shCD147 into MCF7 and MCF7/Adr cells, respectively. Using quantitative real-time polymerase chain reaction and Western blot, we found that overexpression of CD147 in MCF7 cells up-regulated MDR1, MMP2, and MMP9 on both transcription and expression levels, which promoted tumor cells metastasis and conferred them multidrug resistance to P-gp substrate drugs, as determined by in vitro invasion assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. On the other hand, silencing of CD147 in MCF7/Adr cells led to the opposite effect. Moreover, Erk1/2 in CD147-overexpressing clones were observed to be highly activate and after treatment with U0126, an Erk1/2-specific inhibitor, the expression of MDR1, MMP2 and MMP9 were decreased significantly. Thus, CD147 may assume a dual role, since it had intrinsic stimulative effects on tumor invasion in vitro as well as increasing resistance to P-gp substrate drugs.

    Funded by: NCI NIH HHS: CA 66077, CA109371

    Cancer science 2007;98;7;1064-9

  • Useful detection of CD147 (EMMPRIN) for pathological diagnosis of early hepatocellular carcinoma in needle biopsy samples.

    Mamori S, Nagatsuma K, Matsuura T, Ohkawa K, Hano H, Fukunaga M, Matsushima M, Masui Y, Fushiya N, Onoda H, Searashi Y, Takagi I and Tagiri H

    Division of Gastroenterology and Hepatology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan. mamori@jikei.ac.jp

    Aim: To make clear whether CD147 (EMMPRIN) expression in pathological tumor samples with a fine-needle aspiration biopsy is useful for pathological diagnosis of early hepatocellular carcinoma (HCC).

    Methods: Twenty-two patients (15 men and 7 women; median age 68 years, range 56-81 years) underwent a liver tissue biopsy in order to make a diagnosis of HCC. Paraffin-embedded liver biopsy tissue samples from 22 patients were stained with anti-CD147 antibody, murine monoclonal antibody 12C3 (MAb12C3) for immunohistochemical analysis. An immunohistochemical analysis of CD147 was performed and the degree of staining compared between tumor and non-tumor tissue. In addition, the degree of staining within tumor tissue was compared according to a number of clinicopathological variables.

    Results: The degree of staining of CD147 was significantly higher in tumor tissues than non-tumor tissues, even in tumors less than 15 mm in diameter. The expression of this protein was significantly elevated in HCC tissue specimens from patients with a low value of serum AST and gamma-GTP.

    Conclusion: CD147 serves potentially as a pathological target for cancer detection of early HCC.

    World journal of gastroenterology : WJG 2007;13;21;2913-7

  • The tumor suppressor PP2A Abeta regulates the RalA GTPase.

    Sablina AA, Chen W, Arroyo JD, Corral L, Hector M, Bulmer SE, DeCaprio JA and Hahn WC

    Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.

    The serine-threonine protein phosphatase 2A (PP2A) is a heterotrimeric enzyme family that regulates numerous signaling pathways. Biallelic mutations of the structural PP2A Abeta subunit occur in several types of human tumors; however, the functional consequences of these cancer-associated PP2A Abeta mutations in cell transformation remain undefined. Here we show that suppression of PP2A Abeta expression permits immortalized human cells to achieve a tumorigenic state. Cancer-associated Abeta mutants fail to reverse tumorigenic phenotype induced by PP2A Abeta suppression, indicating that these mutants function as null alleles. Wild-type PP2A Abeta but not cancer-derived Abeta mutants form a complex with the small GTPase RalA. PP2A Abeta-containing complexes dephosphorylate RalA at Ser183 and Ser194, inactivating RalA and abolishing its transforming function. These observations identify PP2A Abeta as a tumor suppressor gene that transforms immortalized human cells by regulating the function of RalA.

    Funded by: NCI NIH HHS: P01 CA050661, P01 CA050661-190009, P01 CA50661

    Cell 2007;129;5;969-82

  • HAb18G/CD147 functions in invasion and metastasis of hepatocellular carcinoma.

    Xu J, Xu HY, Zhang Q, Song F, Jiang JL, Yang XM, Mi L, Wen N, Tian R, Wang L, Yao H, Feng Q, Zhang Y, Xing JL, Zhu P and Chen ZN

    Cell Engineering Research Centre and Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 17 West Changle Street, Xi'an 710032, China.

    CD147 molecule is reported to be correlated with the malignancy of some cancers; however, it remains unclear whether it is involved in the progression of hepatocellular carcinoma (HCC). Here, we investigated the function of HAb18G/CD147, a member of CD147 family, and its antibodies, HAb18 and LICARTIN, in HCC invasion and metastasis. We observed that HAb18G/CD147 gene silence in HCC cells significantly decreased the secretion of matrix metalloproteinase (MMP) and the invasive potential of HCC cells (P < 0.001). MMP silence in HCC cells also significantly suppressed the invasion of the cells when cocultured with fibroblasts; however, its inhibitory effect was significantly weaker than that of both HAb18G/CD147 silence in HCC cells and that of MMP silence in fibroblasts (P < 0.001). Blocking theHAb18G/CD147 molecule on HCC cells with HAb18 monoclonal antibody resulted in a similar suppressive effect on MMP secretion and cell invasion, but with no significant effects on the cell growth. (131)I-labeled HAb18 F(ab')(2) (LICARTIN), however, significantly inhibited the in vitro growth of HCC cells (P < 0.001). In an orthotopic model of HCC in nude mice, HAb18 and LICARTIN treatment effectively reduced the tumor growth and metastasis as well as the expression of three major factors in the HCC microenviroment (MMPs, vascular endothelial growth factor, and fibroblast surface protein) in the paracancer tissues. Overall, these results suggest that HAb18G/CD147 plays an important role in HCC invasion and metastasis mainly via modulating fibroblasts, as well as HCC cells themselves to disrupt the HCC microenviroment. LICARTIN can be used as a drug targeting to HAb18G/CD147 in antimetastasis and recurrence therapy of HCC.

    Molecular cancer research : MCR 2007;5;6;605-14

  • Epitope mapping of series of monoclonal antibodies against the hepatocellular carcinoma-associated antigen HAb18G/CD147.

    Ku XM, Liao CG, Li Y, Yang XM, Yang B, Yao XY, Wang L, Kong LM, Zhao P and Chen ZN

    Cell Engineering Research Center & Department of Cell Biology, State Key Laboratory of Cancer Biology, The Fourth Military Medical University, Xi'an, China.

    The hepatocellular carcinoma-associated antigen HAb18G/CD147, a member of CD147 family, could promote tumour invasion and metastasis via inducing the secretion of matrix metalloproteinases (MMP). Anti-CD147 monoclonal antibodies (MoAb) have exhibited obvious inhibitory effect on MMP induction. However, none of the epitopes of these MoAb has been reported. We previously prepared five MoAb against HAb18G/CD147, named HAb18, 3B3, 1B3, 5A5 and 4D2. To map the epitopes of these MoAb, a series of truncated fragments of extracellular region of HAb18G/CD147 was expressed in Escherichia coli and the MoAb-binding affinity to these fragments was examined with an enzyme-linked immunosorbent assay and Western blot. The residues (39)LTCSLNDSATEV(50), (36)KILLTCS(42) and (22)AAGTVFTTVEDL(33) were determined to be the epitopes of HAb18, 3B3 and 1B3, respectively, which were further proved by a dot-blot analysis with synthesized peptides and bioinformatics epitope prediction. The binding regions of MoAb 5A5 and 4D2 were located at residues E(120)-R(203). Then we constructed and expressed full-length HAb18G/CD147 and truncated HAb18G/CD147 without residues A(22)-V(50) in COS-7 cells. Gelatin zymography and Boyden chamber assay showed that the COS-7 cells expressing truncated HAb18G/CD147 failed to induce MMP production and enhance the cells' invasive potential, compared with the cells expressing full-length HAb18G/CD147. Taken together with the obviously inhibitory effects of HAb18 on the function of full-length HAb18G/CD147, these findings suggest that residues (22)AAGTVFTTVEDLGSKILLTCSLNDSATEV(50) may play a critical role in the functions of HAb18G/CD147 on MMP secretion and tumour invasion. These key residues can be used as potential drug target in cancer therapy.

    Scandinavian journal of immunology 2007;65;5;435-43

  • Junction protein shrew-1 influences cell invasion and interacts with invasion-promoting protein CD147.

    Schreiner A, Ruonala M, Jakob V, Suthaus J, Boles E, Wouters F and Starzinski-Powitz A

    Institute of Cell Biology and Neuroscience, Johann Wolfgang Goethe University of Frankfurt, D-60323 Frankfurt am Main, Germany.

    Shrew-1 was previously isolated from an endometriotic cell line in our search for invasion-associated genes. It proved to be a membrane protein that targets to the basolateral membrane of polarized epithelial cells, interacting with E-cadherin-catenin complexes of adherens junctions. Paradoxically, the existence of adherens junctions is incompatible with invasion. To investigate whether shrew-1 can indeed influence cellular invasion, we overexpressed it in HT1080 fibrosarcoma cells. This resulted in enhanced invasiveness, accompanied by an increased matrix metalloprotease (MMP)-9 level in the supernatant, raising the question about the role of shrew-1 in this process. Logic suggested we looked for an interaction with CD147, a known promoter of invasiveness and MMP activity. Indeed, genetics-based, biochemical, and microscopy experiments revealed shrew-1- and CD147-containing complexes in invasive endometriotic cells and an interaction in epithelial cells, which was stronger in MCF7 tumor cells, but weaker in Madin-Darby canine kidney cells. In contrast to the effect mediated by overexpression, small interfering RNA-mediated down-regulation of either shrew-1 or CD147 in HeLa cells decreased invasiveness without affecting the proliferation behavior of HeLa cells, but the knockdown cells displayed decreased motility. Altogether, our results imply that shrew-1 has a function in the regulation of cellular invasion, which may involve its interaction with CD147.

    Molecular biology of the cell 2007;18;4;1272-81

  • Tumor vesicle-associated CD147 modulates the angiogenic capability of endothelial cells.

    Millimaggi D, Mari M, D'Ascenzo S, Carosa E, Jannini EA, Zucker S, Carta G, Pavan A and Dolo V

    Department of Experimental Medicine, L'Aquila University, L'Aquila, Italy.

    Matrix metalloproteinase (MMP) degradation of extracellular matrix is thought to play an important role in invasion, angiogenesis, tumor growth, and metastasis. Several studies have demonstrated that CD147/extracellular MMP inducer, a membrane-spanning molecule highly expressed in tumor cells, may be involved in the progression of malignancies by regulating expression of MMP in peritumoral stromal cells. In the present study we show that CD147 is expressed in microvesicles derived from epithelial ovarian cancer cells and that CD147-positive vesicles may promote an angiogenic phenotype in endothelial cells in vitro. Vesicles shed by human ovarian carcinoma cell lines OVCAR3, SKOV3, and A2780 expressed different levels of CD147 and stimulated proangiogenic activities of human umbilical vein endothelial cells (HUVECs) in a CD147-dependent fashion (OVCAR3 > SKOV3 > A2780). Moreover, vesicles shed by ovarian carcinoma cell line CABA I with low CD147 expression had no significant effect on the development of angiogenic phenotype in HUVECs. The treatment of OVCAR3 cells with small interfering RNA against CD147 suppressed the angiogenic potential of OVCAR3-derived microvesicles. However, transfection of CD147 cDNA into the CABA I cell line enabled CABA I-derived vesicles to induce angiogenesis and to promote MMP genes expression in HUVECs. We therefore conclude that vesicles shed by ovarian cancer cells may induce proangiogenic activities of HUVECs by a CD147-mediated mechanism.

    Neoplasia (New York, N.Y.) 2007;9;4;349-57

  • High incidence of extracellular matrix metalloproteinase inducer expression in non-small cell lung cancers. Association with clinicopathological parameters.

    Hakuma N, Betsuyaku T, Kinoshita I, Itoh T, Kaga K, Kondo S, Nishimura M and Dosaka-Akita H

    First Department of Medicine, Hokkaido University School of Medicine, Sapporo, Japan.

    Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) is a highly glycosylated transmembrane protein that is widely present on the surface of various tumor cells, assisting in tumor progression by stimulating the production of several matrix metalloproteinases in adjacent stromal cells. However, its clinical relevance remains to be evaluated in lung cancers. Therefore, we aimed to investigate the relationship between EMMPRIN expression in non-small cell lung cancer (NSCLC) and clinicopathological characteristics and prognosis.

    Methods: EMMPRIN expression was semiquantified by immunohistochemistry with anti-human EMMPRIN monoclonal antibody in 208 surgically resected NSCLCs and was analyzed statistically in relation to various characteristics.

    Results: EMMPRIN expression was seen in most NSCLC samples (92%). High levels of EMMPRIN expression were significantly associated with differentiation and pT(1) stage in adenocarcinomas. There were no significant differences in overall survival between patients with tumors having high and low levels of EMMPRIN expression in pathological stage I NSCLCs (5-year survival rates, 69 vs. 60%).

    Conclusions: EMMPRIN was preferentially expressed in most NSCLCs. High levels of expression were associated with early T stage and well-differentiated adenocarcinoma, and were not a prognostic factor in NSCLC.

    Oncology 2007;72;3-4;197-204

  • Large-scale mapping of human protein-protein interactions by mass spectrometry.

    Ewing RM, Chu P, Elisma F, Li H, Taylor P, Climie S, McBroom-Cerajewski L, Robinson MD, O'Connor L, Li M, Taylor R, Dharsee M, Ho Y, Heilbut A, Moore L, Zhang S, Ornatsky O, Bukhman YV, Ethier M, Sheng Y, Vasilescu J, Abu-Farha M, Lambert JP, Duewel HS, Stewart II, Kuehl B, Hogue K, Colwill K, Gladwish K, Muskat B, Kinach R, Adams SL, Moran MF, Morin GB, Topaloglou T and Figeys D

    Protana, Toronto, Ontario, Canada.

    Mapping protein-protein interactions is an invaluable tool for understanding protein function. Here, we report the first large-scale study of protein-protein interactions in human cells using a mass spectrometry-based approach. The study maps protein interactions for 338 bait proteins that were selected based on known or suspected disease and functional associations. Large-scale immunoprecipitation of Flag-tagged versions of these proteins followed by LC-ESI-MS/MS analysis resulted in the identification of 24,540 potential protein interactions. False positives and redundant hits were filtered out using empirical criteria and a calculated interaction confidence score, producing a data set of 6463 interactions between 2235 distinct proteins. This data set was further cross-validated using previously published and predicted human protein interactions. In-depth mining of the data set shows that it represents a valuable source of novel protein-protein interactions with relevance to human diseases. In addition, via our preliminary analysis, we report many novel protein interactions and pathway associations.

    Molecular systems biology 2007;3;89

  • Prognostic significance of extracellular matrix metalloproteinase inducer and matrix metalloproteinase 2 in epithelial ovarian cancer.

    Sillanpää S, Anttila M, Suhonen K, Hämäläinen K, Turpeenniemi-Hujanen T, Puistola U, Tammi M, Sironen R, Saarikoski S and Kosma VM

    Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Kuopio, Kuopio, Finland.

    Aims: We investigated the prognostic significance of extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase 2 (MMP-2) in epithelial ovarian cancer as well as their relation to hyaluronan (HA) expression.

    Methods: The expression of EMMPRIN and MMP-2 was analyzed immunohistochemically in 295 primary epithelial ovarian cancer patients and 67 metastases.

    Results: A low membranous EMMPRIN expression was detected more often in serous tumors than in other types (p < 0.0005) and it was associated with tumors of advanced stage (p = 0.012) or with a large primary residual (p = 0.011). A low expression of MMP-2 in cancer cells was associated with a high histologic grade (grade 3) of the tumor (p = 0.005) and endometrioid type of tumors (p < 0.0005). Stromal MMP-2 expression was significantly associated with strong stromal HA expression (p = 0.002, r = 0.187). In univariate analysis, 10-year disease-related (DRS) and recurrence-free survivals were significantly better when MMP-2 expression in cancer cells was high (p = 0.0057 and p = 0.0467, respectively). DRS was also better when membranous EMMPRIN expression was high (p = 0.013). In multivariate analysis, strong MMP-2 in cancer cells (RR = 1.48, CI = 1.07-2.04, p = 0.017) indicated favorable DRS.

    Conclusion: Our results show that EMMPRIN and MMP-2 in cancer cells are significant indicators of a favorable prognosis of epithelial ovarian cancer.

    Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine 2007;28;5;280-9

  • Membrane type 1 matrix metalloproteinase (MT1-MMP/MMP-14) cleaves and releases a 22-kDa extracellular matrix metalloproteinase inducer (EMMPRIN) fragment from tumor cells.

    Egawa N, Koshikawa N, Tomari T, Nabeshima K, Isobe T and Seiki M

    Division of Cancer Cell Research, Institute of Medical Science, the University of Tokyo, Tokyo 108-8639, Japan.

    Proteolytic shedding is an important step in the functional down-regulation and turnover of most membrane proteins at the cell surface. Extracellular matrix metalloproteinase inducer (EMMPRIN) is a multifunctional glycoprotein that has two Ig-like domains in its extracellular portion and functions in cell adhesion as an inducer of matrix metalloproteinase (MMP) expression in surrounding cells. Although the shedding of EMMPRIN is reportedly because of cleavage by metalloproteinases, the responsible proteases, cleavage sites, and stimulants are not yet known. In this study, we found that human tumor HT1080 and A431 cells shed a 22-kDa EMMPRIN fragment into the culture medium. The shedding was enhanced by phorbol 12-myristate 13-acetate and inhibited by TIMP-2 but not by TIMP-1, suggesting the involvement of membrane-type MMPs (MT-MMPs). Indeed, down-regulation of the MT1-MMP expression in A431 cells using small interfering RNA inhibited the shedding. The 22-kDa fragment was purified, and the C-terminal amino acid was determined. A synthetic peptide spanning the cutting site was cleaved by MT1-MMP in vitro. The cleavage site is located in the linker region connecting the two Ig-like domains. The N-terminal Ig-like domain is important for the MMP inducing activity of EMMPRIN and for cell-cell interactions, presumably through its ability to engage in homophilic interactions, and the 22-kDa fragment retained the ability to augment MMP-2 expression in human fibroblasts. Thus, the MT1-MMP-dependent cleavage eliminates the functional N-terminal domain of EMMPRIN from the cell surface, which is expected to down-regulate its function. At the same time, the released 22-kDa fragment may mediate the expression of MMPs in tumor tissues.

    The Journal of biological chemistry 2006;281;49;37576-85

  • A small interfering CD147-targeting RNA inhibited the proliferation, invasiveness, and metastatic activity of malignant melanoma.

    Chen X, Lin J, Kanekura T, Su J, Lin W, Xie H, Wu Y, Li J, Chen M and Chang J

    Department of Dermatology, XiangYa Hospital, Central South University, Changsha, Hunan, China. chenxck@yahoo.com

    CD147 plays a critical role in the invasive and metastatic activity of malignant melanoma cells by stimulating the surrounding fibroblasts to express matrix metalloproteinases and vascular endothelial growth factor. We developed a system that blocks CD147 in the human malignant melanoma cell line, A375, using RNA interference. By transfecting melanoma cells with the small interfering RNA (siRNA) that targets human CD147, we were able to establish two stable clones in which CD147 expression was significantly down-regulated. This resulted in the decreased proliferation and invasion of A375 cells in vitro. CD147 siRNA also down-regulated the expression of vascular endothelial growth factor in these cells and reduced the migration of vascular endothelial cells. The reduction in the CD147 level suppressed the size of s.c. tumors and the microvessel density in an A375 s.c. nude mouse xenograft model. In addition, the in vivo metastatic potential of A375 cells transfected with CD147 siRNA was suppressed in a nude mouse model of pulmonary metastasis.

    Cancer research 2006;66;23;11323-30

  • Gingival crevicular fluid matrix metalloproteinase (MMP)-7, extracellular MMP inducer, and tissue inhibitor of MMP-1 levels in periodontal disease.

    Emingil G, Tervahartiala T, Mãntylã P, Määttä M, Sorsa T and Atilla G

    Department of Periodontology, School of Dentistry, Ege University, Izmir, Turkey. gemingil@yahoo.com

    Background: During periodontal inflammation, matrix metalloproteinases (MMPs) are under the control of several regulatory mechanisms including the upregulation of expression by inducers and downregulation by inhibitors. Our study aimed to examine the levels and molecular forms of MMP-7, tissue inhibitor of MMP (TIMP)-1, and extracellular matrix metalloproteinase inducer (EMMPRIN) in gingival crevicular fluid (GCF) from patients with different periodontal diseases.

    Methods: A total of 80 subjects (20 patients with generalized aggressive periodontitis [GAgP], 20 with chronic periodontitis [CP], 20 with gingivitis, and 20 periodontally healthy subjects) were included in this study. Periodontal status was evaluated by measuring probing depth, clinical attachment loss, presence of bleeding on probing, and plaque. GCF MMP-7, TIMP-1, and EMMPRIN levels and molecular forms were analyzed by enzyme-linked immunosorbent assay (ELISA) and Western immunoblot techniques using specific antibodies.

    Results: Total amounts of GCF MMP-7 were found to be similar between the study groups. GAgP, CP, and gingivitis groups had significantly higher total amounts of GCF EMMPRIN compared to healthy subjects (P <0.008). Among the patient groups, the GAgP group had the highest total amount of GCF EMMPRIN relative to the gingivitis group (P = 0.0004). Soluble EMMPRIN existed in GCF in multiple molecular-weight species especially in periodontitis-affected GCF under non-reducing conditions, i.e., 30-, 55-, 100-, 180-, and 200-kDa species. All patient groups had significantly elevated total amounts of GCF TIMP-1 relative to the healthy group (P <0.0001). GAgP and CP groups also had a higher total amount of GCF TIMP-1 compared to the gingivitis group (P <0.0001 and P <0.0001, respectively). The GAgP group had higher GCF TIMP-1 and EMMPRIN levels compared to the CP group, but this elevation did not reach statistical significance.

    Conclusions: Our data indicate that MMP-7 is associated with the innate host defense in periodontal tissues. Increased EMMPRIN and TIMP-1 levels in GCF are associated with the enhanced severity of periodontal inflammation, indicating that these molecules can participate in the regulation of progression of periodontal diseases. To our knowledge, the present study demonstrated the presence of soluble forms of EMMPRIN in GCF of patients with different periodontal diseases for the first time.

    Journal of periodontology 2006;77;12;2040-50

  • Upregulated EMMPRIN/CD147 might contribute to growth and angiogenesis of gastric carcinoma: a good marker for local invasion and prognosis.

    Zheng HC, Takahashi H, Murai Y, Cui ZG, Nomoto K, Miwa S, Tsuneyama K and Takano Y

    Department of Diagnostic Pathology, Graduate School of Medical and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.

    Tumour growth depends on angiogenesis, which is closely associated with vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). Extracellular MMP inducer (EMMPRIN) was reported to involve in the progression of malignancies by regulating expression of VEGF and MMPs in stromal cells. To clarify the role of EMMPRIN in progression and angiogenesis of gastric carcinoma, expression of EMMPRIN, ki-67, MMP-2, MMP-9 and VEGF was examined on tissue microarray containing gastric carcinomas (n=234) and non-cancerous mucosa adjacent to carcinoma (n=85) by immunohistochemistry. Additionally, microvessel density (MVD) was assessed after labelling with anti-CD34 antibody. Extracellular MMP inducer expression was compared with clinicopathological parameters of tumours, including levels of ki-67, MMP-2, MMP-9 and vascular endothelial growth factor (VEGF), MVD as well as survival time of carcinoma patients. Gastric carcinoma cell lines (HGC-27, MKN28 and MKN45) were studied for EMMPRIN expression by immunohistochemistry and Western blot. Extracellular MMP inducer expression was gradually increased from normal mucosa to carcinomas through hyperplastic or metaplastic mucosa of the stomach (P<0.05). There was strong EMMPRIN expression in all gastric carcinoma cell lines despite different levels of glycosylation. Extracellular MMP inducer expression was positively correlated with tumour size, depth of invasion, lymphatic invasion, expression of ki-67, MMP-2, MMP-9 and VEGF of tumours (P<0.05), but not with lymph node metastasis, UICC staging or differentiation (P>0.05). Interestingly, there was a significantly positive relationship between EMMPRIN expression and MVD in gastric carcinomas (P<0.05). Survival analysis indicated EMMPRIN expression to be negatively linked to favourable prognosis (P<0.05), but not be independent factor for prognosis (P>0.05). Further analysis showed three independent prognostic factors, depth of invasion, lymphatic and venous invasion, to influence the relationship between EMMPRIN expression and prognosis. Upregulated expression of EMMPRIN possibly contributes to genesis, growth and local invasion of gastric carcinomas. Altered EMMPRIN expression might enhance growth, invasion and angiogenesis of gastric carcinoma via upregulating MMP expression of both stromal fibroblasts and gastric cancer cells and could be considered as an objective and effective marker to predict invasion and prognosis.

    British journal of cancer 2006;95;10;1371-8

  • Global, in vivo, and site-specific phosphorylation dynamics in signaling networks.

    Olsen JV, Blagoev B, Gnad F, Macek B, Kumar C, Mortensen P and Mann M

    Center for Experimental BioInformatics, Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark.

    Cell signaling mechanisms often transmit information via posttranslational protein modifications, most importantly reversible protein phosphorylation. Here we develop and apply a general mass spectrometric technology for identification and quantitation of phosphorylation sites as a function of stimulus, time, and subcellular location. We have detected 6,600 phosphorylation sites on 2,244 proteins and have determined their temporal dynamics after stimulating HeLa cells with epidermal growth factor (EGF) and recorded them in the Phosida database. Fourteen percent of phosphorylation sites are modulated at least 2-fold by EGF, and these were classified by their temporal profiles. Surprisingly, a majority of proteins contain multiple phosphorylation sites showing different kinetics, suggesting that they serve as platforms for integrating signals. In addition to protein kinase cascades, the targets of reversible phosphorylation include ubiquitin ligases, guanine nucleotide exchange factors, and at least 46 different transcriptional regulators. The dynamic phosphoproteome provides a missing link in a global, integrative view of cellular regulation.

    Cell 2006;127;3;635-48

  • The role of charged residues in the transmembrane helices of monocarboxylate transporter 1 and its ancillary protein basigin in determining plasma membrane expression and catalytic activity.

    Manoharan C, Wilson MC, Sessions RB and Halestrap AP

    Department of Biochemistry, University of Bristol, School of Medical Sciences, University Walk, Bristol, UK.

    Monocarboxylate transporters MCT1-MCT4 require basigin (CD147) or embigin (gp70), ancillary proteins with a glutamate residue in their single transmembrane (TM) domain, for plasma membrane (PM) expression and activity. Here we use site-directed mutagenesis and expression in COS cells or Xenopus oocytes to investigate whether this glutamate (Glu218 in basigin) may charge-pair with a positively charged TM-residue of MCT1. Such residues were predicted using a new molecular model of MCT1 based upon the published structure of the E. coli glycerol-3-phosphate transporter. No evidence was obtained for Arg306 (TM 8) of MCT1 and Glu218 of basigin forming a charge-pair; indeed E218Q-basigin could replace WT-basigin, although E218R-basigin was inactive. No PM expression of R306E-MCT1 or D302R-MCT1 was observed but D302R/R306D-MCT1 reached the PM, as did R306K-MCT1. However, both were catalytically inactive suggesting that Arg306 and Asp302 form a charge-pair in either orientation, but their precise geometry is essential for catalytic activity. Mutation of Arg86 to Glu or Gln within TM3 of MCT1 had no effect on plasma membrane expression or activity of MCT1. However, unlike WT-MCT1, these mutants enabled expression of E218R-basigin at the plasma membrane of COS cells. We propose that TM3 of MCT1 lies alongside the TM of basigin with Arg86 adjacent to Glu218 of basigin. Only when both these residues are positively charged (E218R-basigin with WT-MCT1) is this interaction prevented; all other residue pairings at these positions may be accommodated by charge-pairing or stabilization of unionized residues through hydrogen bonding or local distortion of the helical structure.

    Funded by: Wellcome Trust: 079792

    Molecular membrane biology 2006;23;6;486-98

  • Proteomic and bioinformatic characterization of the biogenesis and function of melanosomes.

    Chi A, Valencia JC, Hu ZZ, Watabe H, Yamaguchi H, Mangini NJ, Huang H, Canfield VA, Cheng KC, Yang F, Abe R, Yamagishi S, Shabanowitz J, Hearing VJ, Wu C, Appella E and Hunt DF

    Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.

    Melanin, which is responsible for virtually all visible skin, hair, and eye pigmentation in humans, is synthesized, deposited, and distributed in subcellular organelles termed melanosomes. A comprehensive determination of the protein composition of this organelle has been obstructed by the melanin present. Here, we report a novel method of removing melanin that includes in-solution digestion and immobilized metal affinity chromatography (IMAC). Together with in-gel digestion, this method has allowed us to characterize melanosome proteomes at various developmental stages by tandem mass spectrometry. Comparative profiling and functional characterization of the melanosome proteomes identified approximately 1500 proteins in melanosomes of all stages, with approximately 600 in any given stage. These proteins include 16 homologous to mouse coat color genes and many associated with human pigmentary diseases. Approximately 100 proteins shared by melanosomes from pigmented and nonpigmented melanocytes define the essential melanosome proteome. Proteins validated by confirming their intracellular localization include PEDF (pigment-epithelium derived factor) and SLC24A5 (sodium/potassium/calcium exchanger 5, NCKX5). The sharing of proteins between melanosomes and other lysosome-related organelles suggests a common evolutionary origin. This work represents a model for the study of the biogenesis of lysosome-related organelles.

    Funded by: NCRR NIH HHS: RR01744; NHGRI NIH HHS: U01-HG02712; NICHD NIH HHS: HD40179; NIGMS NIH HHS: GM 37537

    Journal of proteome research 2006;5;11;3135-44

  • High incidence of EMMPRIN expression in human tumors.

    Riethdorf S, Reimers N, Assmann V, Kornfeld JW, Terracciano L, Sauter G and Pantel K

    Institute of Tumor Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

    Extracellular matrix metalloproteinase inducer expressed by tumor cells stimulates peritumoral fibroblasts to produce matrix metalloproteinases, thus contributing to tumor invasion and metastasis. To assess its suitability as potential therapeutic target, the overall incidence of EMMPRIN expression in normal and neoplastic tissues was analyzed. EMMPRIN expression was detected immunohistochemically using monoclonal antibodies MEM-M6/1 and HIM6 and tissue microarrays with 2,348 and 608 tissue samples from 129 distinct tumor types and 76 different normal tissues, respectively. Expression and glycosylation state of EMMPRIN in human breast cancer cells were analyzed by Western blot analysis with monoclonal antibodies recognizing distinct carbohydrate structures and biochemical methods. EMMPRIN expression was found in 112 of 129 tumor entities analyzed with malignant tumors being EMMPRIN positive more frequently than benign tumors. A remarkable heterogeneity in EMMPRIN expression between tumor entities was observed. Among others, squamous-cell carcinomas (60-100%), pancreatic (87%), chromophobic kidney (83%), hepatocellular (83%) or medullary breast (83%) adenocarcinomas as well as glioblastoma multiforme (79%) presented with a particular high incidence of EMMPRIN expression. There were a limited number of EMMPRIN-positive normal cell types including proliferatively active and differentiating epithelial cells, germ cells, myocardial cells in the left heart ventricle or vascular endothelial cells of the brain. We could further demonstrate that breast cancer cells expressed EMMPRIN isoforms differing in the presence or absence of Lewis X glycan structures. Our results may assist in defining the suitability of EMMPRIN as therapeutic target and predicting negative side effects.

    International journal of cancer 2006;119;8;1800-10

  • Cytokines regulate matrix metalloproteinases in human uterine endometrial fibroblast cells through a mechanism that does not involve increases in extracellular matrix metalloproteinase inducer.

    Braundmeier AG and Nowak RA

    Department of Animal Sciences, University of Illinois, Urbana, USA.

    Problem: Endometriosis is the presence of ectopic uterine endometrial tissue in the peritoneal cavity. Peritoneal fluid samples of women with endometriosis show elevated interleukin-1 (IL-1)beta, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta(1) levels, indicating that an altered immune system may play an important role in the pathogenesis of endometriosis. The invasion of ectopic endometrium into peritoneal mesothelium requires matrix metalloproteinases (MMPs) for tissue remodeling. Several MMPs are differentially expressed in human uterine endometrium with menstrual endometrium showing the highest level of expression. MMPs are stimulated by cytokines and also by the protein Extracellular Matrix Metalloproteinase Inducer (EMMPRIN).

    To determine the role of cytokines in ectopic endometrial invasion, we investigated whether cytokines could regulate MMP production by endometrial fibroblast cells and whether this stimulation occurred through an effect on EMMPRIN expression. Human uterine fibroblasts (HUF) were treated with IL-1beta, TGF-beta(1) and TNF-alpha in a dose dependent and time dependent manner (C, 0.1, 1, 10 ng/mL IL-1beta or TGF-beta(1); C, 2, 10, 50 ng/mL TNF-alpha) for 0, 6, 12, and 24 hr. Cell conditioned medium samples were collected and concentrated at each timepoint for immunoblot analysis. Cellular RNA was collected for real time PCR analysis of MMPs-1, -2, -3 and EMMPRIN mRNA levels.

    Results: Our results showed that IL-1beta stimulated MMP-1 protein secretion and mRNA levels in a time dependent manner (P < 0.05), MMP-2 mRNA in a time dependent manner and MMP-3 in a time and dose dependent manner. TNF-alpha stimulated MMP-1 and -3 protein secretion in a time dependent manner and stimulated MMP-1, -2 and -3 mRNA levels in a time dependent manner (P < 0.05). Neither IL-1beta nor TNF-alpha treatment affected MMP-2 protein secretion. TGF-beta(1) inhibited MMP-1 and MMP-2 mRNAs at the highest treatment dose after 24 hr but there was no effect on protein secretion. TGF-beta(1) exerted no effect on MMP-3 mRNA or protein secretion (P < 0.05). Neither of the cytokines affected EMMPRIN protein or mRNA levels but the 10 ng/mL TGF-beta(1) treatment did cause a reduction in EMMPRIN mRNA levels.

    Conclusions: These data show that elevated cytokines may play a role in the establishment of ectopic endometrium in the peritoneal cavity by stimulating MMPs to remodel the mesothelial lining of the peritoneum thus allowing for tissue invasion. The stimulation of MMPs by cytokines occurred without any change in EMMPRIN expression whereas the inhibitory effect of TGF-beta(1) involved a reduction in EMMPRIN mRNA levels.

    Funded by: NICHD NIH HHS: U54 HD40093

    American journal of reproductive immunology (New York, N.Y. : 1989) 2006;56;3;201-14

  • EMMPRIN-induced MMP-2 activation cascade in human cervical squamous cell carcinoma.

    Sier CF, Zuidwijk K, Zijlmans HJ, Hanemaaijer R, Mulder-Stapel AA, Prins FA, Dreef EJ, Kenter GG, Fleuren GJ and Gorter A

    Department of Pathology, Leiden University Medical Center, The Netherlands. C.F.M.Sier@lumc.nl

    Tumor progression and recurrence of cervical cancer is associated with upregulation of matrix metalloproteinase 2 (MMP-2). We evaluated the location, origin and activity of MMP-2 in cervical squamous cell carcinomas in comparison with MT1-MMP (MMP-14), TIMP-2 and extracellular matrix metalloproteinase inducer (EMMPRIN). Positive immunostaining for MMP-2 in malignant cells was detected in 83% of the patients. Two patterns of tumor cell MMP-2 staining were observed: either homogenous in all tumor cells or confined to the cells neighboring the stroma (tumor-border staining pattern, TBS). Fluorescence in situ zymography showed active MMP-2 mainly around tumor nodules displaying TBS. The MMP-2 staining of TBS tumors correlated significantly with the presence of TIMP-2 and MT1-MMP, proteins involved in docking MMP-2 to the cell surface and essential for MMP-2 activation. In situ mRNA hybridization in TBS tumors demonstrated more abundant presence of MMP-2 mRNA in neighboring myofibroblasts than in the adjacent tumor cells. Moreover, the TBS MMP-2 pattern correlated with the presence of EMMPRIN (p = 0.023), suggesting that tumor cells induce MMP-2 production in nearby stromal cells. This pro-MMP-2 could subsequently be activated on tumor cells via the presence of MT1-MMP and TIMP-2. The biological relevance of this locally activated MMP-2 was underscored by the observation that only the TBS pattern of MMP-2 significantly correlated with decreased survival. In conclusion, the colocalization of EMMPRIN, MT1-MMP and TIMP-2 in human cervical carcinomas seems to be involved in a specific distribution pattern of tumor cell bound MMP-2, which is related with local proteolytic activity and therefore might be associated with worse prognosis of the patients.

    International journal of cancer. Journal international du cancer 2006;118;12;2991-8

  • Inhibition of CD147 expression reduces tumor cell invasion in human prostate cancer cell line via RNA interference.

    Wang L, Wu G, Yu L, Yuan J, Fang F, Zhai Z, Wang F and Wang H

    Department of Urology, Xijing Hospital, Fourth Military Medical University, Xi'an City, China.

    CD147, also named extracelluar matrix metalloproteinase inducer (EMMPRIN), has been proved to be involved in the invasion and metastasis processes of tumor cells in many types of cancers. To determine the role of CD147 in the invasiveness properties of prostate cancer, we successfully downregulated CD147 by RNA interference (RNAi) technology, in PC-3 cell line at high level of CD147 expression. PC-3 cells were transfected with a pSilencer 4.1-CMV neo Vector coding for an RNA composed of two identical 19-nucleotide sequence motifs in an inverted orientation, separated by a 9-bp spacer to form a hairpin dsRNA capable of mediating target CD147 inhibition. Gelatin zymography was employed to determine the effect on reducing secretions of MMP-2 and MMP-9 of the transfected cells. Matrigel invasion assay was performed to evaluate the invasion ability of PC-3 cells in vitro. Our results showed that CD147 expression was significantly inhibited by small interfering RNAs (siRNA) transfectants in PC-3 cells at mRNA and protein levels, which resulted in dramatic reduction of invasion ability in tumor cells. Moreover, downregulation of CD147 resulted in reducing secretions of MMP-2, MMP-9. Taken together, CD147 downregulation by RNAi technology decreases the invasive capability of prostate cancer cells, demonstrating that stable expression of siRNA CD147 could potentially be an experimental approach for prostate cancer gene therapy.

    Cancer biology & therapy 2006;5;6;608-14

  • Regulation of vascular endothelial growth factor expression by EMMPRIN via the PI3K-Akt signaling pathway.

    Tang Y, Nakada MT, Rafferty P, Laraio J, McCabe FL, Millar H, Cunningham M, Snyder LA, Bugelski P and Yan L

    Oncology Research, Centocor R&D, Inc., Malvern, Pennsylvania 19355, USA.

    Extracellular matrix metalloproteinase (MMP) inducer (EMMPRIN) is a cell surface glycoprotein overexpressed in many solid tumors. In addition to its ability to stimulate stromal MMP expression, tumor-associated EMMPRIN also induces vascular endothelial growth factor (VEGF) expression. To explore the underlying signaling pathways used by EMMPRIN, we studied the involvement of phosphoinositide 3-kinase (PI3K)-Akt, mitogen-activated protein kinase (MAPK), JUN, and p38 kinases in EMMPRIN-mediated VEGF regulation. Overexpression of EMMPRIN in MDA-MB-231 breast cancer cells stimulated the phosphorylation of only Akt and MAPKs but not that of JUN and p38 kinases. Conversely, inhibition of EMMPRIN expression resulted in suppressed Akt and MAPK phosphorylation. Furthermore, the PI3K-specific inhibitor LY294002 inhibited VEGF production by EMMPRIN-overexpressing cells in a dose- and time-dependent manner. On the other hand, the MAPK inhibitor U0126 did not affect VEGF production. In vivo, EMMPRIN-overexpressing tumors with elevated VEGF expression had a high level of phosphorylation of Akt and MAPK. Finally, when fibroblast cells were treated with recombinant EMMPRIN, Akt kinase but not MAPK was phosphorylated concomitant with an increase in VEGF production. Both the activation of Akt kinase and the induction of VEGF were specifically inhibited with a neutralizing antibody to EMMPRIN. Our results show that in both tumor and fibroblast cells EMMPRIN regulates VEGF production via the PI3K-Akt pathway but not via the MAPK, JUN, or p38 kinase pathways.

    Molecular cancer research : MCR 2006;4;6;371-7

  • Increasing expression of extracellular matrix metalloprotease inducer in renal cell carcinoma: tissue microarray analysis of immunostaining score with clinicopathological parameters.

    Jin JS, Hsieh DS, Lin YF, Wang JY, Sheu LF and Lee WH

    Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. jsjin@ndmctsgh.edu.tw

    Aim: Renal tumor cell invasion is responsible for both local tissue destruction and distant metastasis. Invasion is largely mediated by matrix metalloproteases that are thought to be induced by tumor cell-derived extracellular matrix metalloprotease inducer (EMMPRIN) in surrounding fibroblasts. We hypothesized that EMMPRIN and matrix metalloproteinase-9 (MMP-9) are over-expressed in renal cell carcinoma.

    Methods: Immunohistochemical analysis of EMMPRIN and MMP-9 was performed in tissue microarrays of 79 renal cell carcinomas including 12 cases of chromophobe renal cell carcinoma (ChRCC), 53 cases of clear cell renal cell carcinoma (CRCC), 8 cases of papillary renal cell carcinoma (PRCC), and 6 cases of carcinoma of the collecting ducts of Bellini (CoRCC).

    Results: All renal cell carcinomas showed significant immunohistochemical expression of EMMPRIN. The EMMPRIN score in ChRCC (321+/-21) was significantly higher than in other histological subtypes of RCC (166+/-19 for CRCC; 276+/-24 for PRCC; 98+/-17 for CoRCC). MMP-9 was mainly expressed in tumor stromal cells and not in non-cancerous fibrovascular regions. The percent positive staining of MMP-9 at the invasive front of tumor cells was significantly higher in CRCC than in ChRCC, PRCC, or CoRCC. Higher EMMPRIN scores in CRCC were associated with shorter survival time, and correlated with higher T staging and nuclear grading.

    Conclusions: Our findings demonstrate for the first time that EMMPRIN is over-expressed in renal cell carcinomas. Increased expression of EMMPRIN in tumor cells is associated with poor prognosis of patients with CRCC.

    International journal of urology : official journal of the Japanese Urological Association 2006;13;5;573-80

  • Extracellular matrix metalloproteinase inducer (CD147) confers resistance of breast cancer cells to Anoikis through inhibition of Bim.

    Yang JM, O'Neill P, Jin W, Foty R, Medina DJ, Xu Z, Lomas M, Arndt GM, Tang Y, Nakada M, Yan L and Hait WN

    Department of Pharmacology, Medicine and Surgery, The Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey/Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903, USA. jyang@umdnj.edu

    Overexpression of extracellular matrix metalloproteinase inducer (EMMPRIN or CD147), a member of the immunoglobulin family and a glycoprotein enriched on the surface of tumor cells, promotes invasion, metastasis, and growth and survival of malignant cells and confers resistance to some chemotherapeutic drugs. However, the molecular mechanisms underlying the actions of EMMPRIN are not fully understood. In this study we sought to determine whether EMMPRIN contributes to the malignant phenotype of breast cancer by inhibiting anoikis, a form of apoptosis induced by loss or alteration of cell-cell or cell-matrix anchorage, and to explore the signaling pathways involved. We found that in the absence of attachment, human breast carcinoma cells expressing high levels of EMMPRIN formed less compact aggregates with larger surface area and less fibronectin matrix assembly, had higher viability, and were resistant to anoikis. Knockdown of EMMPRIN expression by RNA interference (small interfering RNA or short hairpin RNA) sensitized cancer cells to anoikis, as demonstrated by activation of caspase-3, increased DNA fragmentation, and decreased cellular viability. Furthermore, we observed that the accumulation of Bim, a proapoptotic BH3-only protein, was reduced in EMMPRIN-expressing cells and that silencing of EMMPRIN expression elevated Bim protein levels and enhanced cellular sensitivity to anoikis. Treatment of cells with a MEK inhibitor (U0126) or proteasome inhibitor (epoxomicin) also up-regulated Bim accumulation and rendered cells more sensitive to anoikis. These results indicated that expression of EMMPRIN protects cancer cells from anoikis and that this effect is mediated at least in part by a MAP kinase-dependent reduction of Bim. Because anoikis deficiency is a key feature of neoplastic transformation and invasive growth of epithelial cancer cells, our study on the role of EMMPRIN in anoikis resistance and the mechanism involved underscores the potential of EMMPRIN expression as a prognostic marker and novel target for cancer therapy.

    Funded by: NCI NIH HHS: CA 66077, CA 72720

    The Journal of biological chemistry 2006;281;14;9719-27

  • Increased EMMPRIN (CD 147) expression during oral carcinogenesis.

    Vigneswaran N, Beckers S, Waigel S, Mensah J, Wu J, Mo J, Fleisher KE, Bouquot J, Sacks PG and Zacharias W

    Department of Diagnostic Sciences, The University of Texas Health Science Center at Houston, Dental Branch, 6516 M.D. Anderson Blvd., Room 3.094G, Houston, TX 77030, USA. Nadarajah.Vigneswaran@UTH.TMC.EDU

    Gene expression profiling of oral premalignant (OPM) cells and normal oral epithelial (NOR) cells showed that EMMPRIN expression was markedly upregulated in OPM cells compared to NOR cells. We used an oral squamous cell carcinoma (OSCC) progression model composed of cell lines, organotypic cultures and tissue specimens to characterize EMMPRIN expression patterns by microarray analysis, qRT-PCR, Western blotting and immunohistochemistry. EMMPRIN levels are elevated in OPM and primary and metastatic OSCC cells as compared to NOR. EMMPRIN was detected as high and low glycosylated forms in the OPM and OSCC cellular extracts and was released in the media by OSCC cells but not by OPM cells. EMMPRIN expression in an organotypic culture model of normal and OPM mucosae mirrored the expression patterns in the respective tissues in vivo. EMMPRIN expression was limited to basal cells of normal, benign hyperkeratotic and inflammatory (lichen planus) oral mucosa. EMMPRIN expression is increased in dysplastic leukoplakias spreading to more superficial layers, and its expression levels correlated significantly with the degree of dysplasia. Primary and metastatic OSCC showed strong cell surface expression of EMMPRIN. These results suggest that EMMPRIN overexpression occurs at a very early stage of oral carcinogenesis and plays a contributing role in OSCC tumorigenesis.

    Funded by: NIDCR NIH HHS: DE13150, DE14395

    Experimental and molecular pathology 2006;80;2;147-59

  • Increasing expression of extracellular matrix metalloprotease inducer in ovary tumors: tissue microarray analysis of immunostaining score with clinicopathological parameters.

    Jin JS, Yao CW, Loh SH, Cheng MF, Hsieh DS and Bai CY

    Department of Pathology, and Division of Urology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.

    Ovary cancer invasion is responsible for both local tissue destruction and distant metastasis. Invasion is largely mediated by matrix metalloproteases that are thought to be induced by tumor cell-derived extracellular matrix metalloprotease inducer (EMMPRIN) in surrounding fibroblasts. We hypothesized that EMMPRIN isoverexpressed in ovary tumors. Immunohistochemical analysis of EMMPRIN was performed in tissue microarrays of ovary neoplasms including 84 cases of serous adenocarcinoma, 23 cases of mucinous adenocarcinoma, 10 cases of endometrioid adenocarcinoma, 12 cases of yolk sac tumor, 12 cases of clear cell carcinoma, 8 cases of dysgerminoma, 8 cases of granulosa cell tumor, 6 cases of transitional cell carcinoma, and 6 cases of Brenner tumor. All malignant ovary tumors showed significant immunohistochemical expression of EMMPRIN. The EMMPRIN scores in malignant ovary tumors were significantly higher than their nontumor counterparts (313+/-28 for serous adenocarcinoma; 308+/-25 for mucinous adenocarcinoma; 187+/-19 for endometrioid adenocarcinoma; 265+/-23 for yolk sac tumors; 87+/-13 for clear cellcarcinoma; 126+/-15 for dysgerminoma; 243+/-26 for granulosa cell tumor; 87+/-16 for transitional cell carcinoma). The EMMPRIN score was significantly higher in serous adenocarcinomas than in serous adenomas and serous borderline tumors and was correlated with nodal stage. Our findings show for the first time that EMMPRIN is overexpressed in all malignant ovary tumors.

    International journal of gynecological pathology : official journal of the International Society of Gynecological Pathologists 2006;25;2;140-6

  • Extracellular matrix metalloproteinase inducer regulates matrix metalloproteinase activity in cardiovascular cells: implications in acute myocardial infarction.

    Schmidt R, Bültmann A, Ungerer M, Joghetaei N, Bülbül O, Thieme S, Chavakis T, Toole BP, Gawaz M, Schömig A and May AE

    Deutsches Herzzentrum und Medizinische Klinik I, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.

    Background: Matrix metalloproteinases (MMPs) are thought to promote progression of atherosclerosis and cardiovascular complications such as plaque rupture. It has been suggested that, on tumor cells, the extracellular MMP inducer (EMMPRIN) is involved in MMP synthesis by as yet unknown mechanisms. On cardiovascular cells, regulation of EMMPRIN in vivo or any functional relevance for MMP induction in vitro has not yet been studied. Thus, we studied EMMPRIN expression on monocytes in acute myocardial infarction (MI) and its potential relevance for MMP activation.

    In 20 patients with acute MI, surface expression of EMMPRIN was significantly enhanced on monocytes compared with in 20 patients with chronic stable angina. EMMPRIN upregulation was associated with increased expression of the membrane type 1 MMP (MT1-MMP) on monocytes (flow cytometry) as well as MMP-9 activity (gelatin zymography) in the plasma. At 6 months after successful revascularization, EMMPRIN, MT1-MMP, and MMP-9 had normalized. The secretion of MMP-9 by monocytes was induced by monocyte adhesion to immobilized recombinant EMMPRIN or to EMMPRIN-transfected Chinese hamster ovary cells. Moreover, adherent EMMPRIN-transfected monocytic cells stimulated MMP-2 activity of human vascular smooth muscle cells. Gene silencing of EMMPRIN by small-interfering RNA hindered lipopolysaccharide-induced monocyte secretion of MMP-9, indicating a predominant role of EMMPRIN in MMP-9 induction.

    Conclusions: EMMPRIN and MT1-MMP are upregulated on monocytes in acute MI. During cellular interactions, EMMPRIN stimulates MMP-9 in monocytes and MMP-2 in smooth muscle cells, indicating that EMMPRIN may display a key regulatory role for MMP activity in cardiovascular pathologies.

    Circulation 2006;113;6;834-41

  • Insulin-dependent interactions of proteins with GLUT4 revealed through stable isotope labeling by amino acids in cell culture (SILAC).

    Foster LJ, Rudich A, Talior I, Patel N, Huang X, Furtado LM, Bilan PJ, Mann M and Klip A

    Center for Experimental BioInformatics (CEBI), Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.

    The insulin-regulated glucose transporter (GLUT4) translocates to the plasma membrane in response to insulin in order to facilitate the postprandial uptake of glucose into fat and muscle cells. While early insulin receptor signaling steps leading to this translocation are well defined, the integration of signaling and regulation of GLUT4 traffic remains elusive. Several lines of evidence suggest an important role for the actin cytoskeleton and for protein-protein interactions in regulating GLUT4 localization by insulin. Here, we applied stable isotope labeling by amino acids in cell culture (SILAC) to identify proteins that interact with GLUT4 in an insulin-regulated manner. Myc-tagged GLUT4 (GLUT4myc) stably expressed in L6 myotubes was immunoprecipitated via the myc epitope from total membranes isolated from basal and insulin-stimulated cells grown in medium containing normal isotopic abundance leucine or deuterated leucine, respectively. Proteins coprecipitating with GLUT4myc were analyzed by liquid chromatography/ tandem mass spectrometry. Of 603 proteins quantified, 36 displayed an insulin-dependent change of their interaction with GLUT4myc of more than 1.5-fold in either direction. Several cytoskeleton-related proteins were elevated in immunoprecipates from insulin-treated cells, whereas components of the ubiquitin-proteasome degradation system were generally reduced. Proteins participating in vesicle traffic also displayed insulin-regulated association. Of cytoskeleton-related proteins, alpha-actinin-4 recovery in GLUT4 immunoprecipitates rose in response to insulin 2.1 +/- 0.5-fold by SILAC and 2.9 +/- 0.8-fold by immunoblotting. Insulin caused GLUT4 and alpha-actinin-4 co-localization as revealed by confocal immunofluorescence microscopy. We conclude that insulin elicits changes in interactions between diverse proteins and GLUT4, and that cytoskeletal proteins, notably alpha-actinin-4, associate with the transporter, potentially to facilitate its routing to the plasma membrane.

    Journal of proteome research 2006;5;1;64-75

  • Matrix metalloproteinase 2 is associated with stable and matrix metalloproteinases 8 and 9 with vulnerable carotid atherosclerotic lesions: a study in human endarterectomy specimen pointing to a role for different extracellular matrix metalloproteinase inducer glycosylation forms.

    Sluijter JP, Pulskens WP, Schoneveld AH, Velema E, Strijder CF, Moll F, de Vries JP, Verheijen J, Hanemaaijer R, de Kleijn DP and Pasterkamp G

    Experimental Cardiology Laboratory, University Medical Center, Utrecht, The Netherlands.

    We studied matrix metalloproteinases (MMP) 2, 8, and 9 and extracellular matrix metalloproteinase inducer (EMMPRIN) levels in relation to carotid atherosclerotic plaque characteristics.

    Methods: Carotid atherosclerotic plaques (n=150) were stained and analyzed for the presence of collagen, smooth muscle cell (SMC), and macrophages. Adjacent segments were used to isolate total protein to assess MMP-2 and MMP-9 activities and gelatin breakdown, MMP-8 activity, and EMMPRIN levels.

    Results: Macrophage-rich lesions revealed higher MMP-8 and MMP-9 activities, whereas SMC-rich lesions showed higher MMP-2 activity. The levels of less glycosylated EMMPRIN-45kD were higher in SMC-rich lesions and lower in macrophage-rich plaques. EMMPRIN-45kD was associated with MMP-2 levels, whereas EMMPRIN-58kD was related to MMP-9 levels.

    Conclusions: MMP-2, MMP-8, and MMP-9 activities differed among carotid plaque phenotypes. Different EMMPRIN glycosylation forms are associated with either MMP-2 or MMP-9 activity, which suggests that EMMPRIN glycosylation may play a role in MMP regulation and plaque destabilization.

    Stroke 2006;37;1;235-9

  • The glycosylation characteristic of hepatoma-associated antigen HAb18G/CD147 in human hepatoma cells.

    Yu XL, Jiang JL, Li L, Feng Q, Xu J and Chen ZN

    Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an 710032, PR China.

    HAb18G/CD147 is a highly glycosylated transmembrane protein belonging to the immunoglobulin superfamily. Our previous studies have demonstrated that overexpressing HAb18G/CD147 enhances the metastatic potentials of human hepatoma cells. In the present study, to investigate the glycosylation characteristic of HAb18G/CD147 in human hepatoma cells, HAb18G/CD147 was first purified from human FHCC-98 hepatoma cells by immunoaffinity chromatography, and then introduced into human fibroblasts culture system for matrix metalloproteinases induction. As a result, the elevated levels of matrix metalloproteinases secreted by fibroblasts were detected by gelatin zymography. The lysates of human hepatoma FHCC-98 cell revealed two major forms of HAb18G/CD147 (43-66 and 35 kDa) by western blot assay. To elucidate whether the variation of molecule size were caused by different glycosylation, two different approaches were employed to accomplish this goal: deglycosylation with N-glycosylation inhibitor tunicamycin or endoglycosidases. A single deglycosylated core protein with molecular weight approximately 27 kDa was obtained from both methods. Furthermore, the results of endoglycosidases treatment also showed that two forms of HAb18G/CD147 contain different types of oligosaccharide chains, thus sensitive to different endoglycosidase. In conclusion, the present study demonstrated that purified native HAb18G/CD147 has the bioactivity of stimulating human fibroblasts to produce elevated levels of matrix metalloproteinases, and that the two different forms of HAb18G/CD147 are derived from the single core protein but differ in their degree and types of glycosylation.

    The international journal of biochemistry & cell biology 2006;38;11;1939-45

  • CD147 overexpression on synoviocytes in rheumatoid arthritis enhances matrix metalloproteinase production and invasiveness of synoviocytes.

    Zhu P, Lu N, Shi ZG, Zhou J, Wu ZB, Yang Y, Ding J and Chen ZN

    Department of Clinical Immunology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, PR China.

    Macrophage-like synoviocytes and fibroblast-like synoviocytes (FLS) are known as the most active cells of rheumatoid arthritis (RA) and are close to the articular cartilage in a position enabling them to invade the cartilage. Macrophage-like synoviocytes and FLS expression of matrix metalloproteinases (MMPs) and their interaction has aroused great interest. The present article studied the expression of CD147, also called extracellular matrix metalloproteinase inducer, on monocytes/macrophages and FLS from RA patients and its potential role in enhancing MMPs and the invasiveness of synoviocytes. Expression of CD147 on FLS derived from RA patients and from osteoarthritis patients, and expression of CD147 on monocytes/macrophages from rheumatic synovial fluid and healthy peripheral blood were analyzed by flow cytometry. The levels of CD147, MMP-2 and MMP-9 mRNA in FLS were detected by RT-PCR. The role of CD147 in MMP production and the cells' invasiveness in vitro were studied by the co-culture of FLS with the human THP-1 cell line or monocytes/macrophages, by gel zymography and by invasion assay. The results showed that the expression of CD147 was higher on RA FLS than on osteoarthritis FLS and was higher on monocytes/macrophages from rheumatic synovial fluid than on monocytes/macrophages from healthy peripheral blood. RT-PCR showed that the expressions of CD147, MMP-2 and MMP-9 mRNA was higher in RA FLS than in osteoarthritis FLS. A significantly elevated secretion and activation of MMP-2 and MMP-9 were observed in RA FLS co-cultured with differentiated THP-1 cells or RA synovial monocytes/macrophages, compared with those co-cultured with undifferentiated THP-1 cells or healthy control peripheral blood monocytes. Invasion assays showed an increased number of invading cells in the co-cultured RA FLS with differentiated THP-1 cells or RA synovial monocytes/macrophages. CD147 antagonistic peptide inhibited the MMP production and the invasive potential. Our studies demonstrated that the CD147 overexpression on monocytes/macrophages and FLS in RA patients may be responsible for the enhanced MMP secretion and activation and for the invasiveness of synoviocytes. These findings suggest that CD147 may be one of the important factors in progressive joint destruction of RA and that CD147 may be a potential therapeutic target in RA treatment.

    Arthritis research & therapy 2006;8;2;R44

  • Towards a proteome-scale map of the human protein-protein interaction network.

    Rual JF, Venkatesan K, Hao T, Hirozane-Kishikawa T, Dricot A, Li N, Berriz GF, Gibbons FD, Dreze M, Ayivi-Guedehoussou N, Klitgord N, Simon C, Boxem M, Milstein S, Rosenberg J, Goldberg DS, Zhang LV, Wong SL, Franklin G, Li S, Albala JS, Lim J, Fraughton C, Llamosas E, Cevik S, Bex C, Lamesch P, Sikorski RS, Vandenhaute J, Zoghbi HY, Smolyar A, Bosak S, Sequerra R, Doucette-Stamm L, Cusick ME, Hill DE, Roth FP and Vidal M

    Center for Cancer Systems Biology and Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Boston, Massachusetts 02115, USA.

    Systematic mapping of protein-protein interactions, or 'interactome' mapping, was initiated in model organisms, starting with defined biological processes and then expanding to the scale of the proteome. Although far from complete, such maps have revealed global topological and dynamic features of interactome networks that relate to known biological properties, suggesting that a human interactome map will provide insight into development and disease mechanisms at a systems level. Here we describe an initial version of a proteome-scale map of human binary protein-protein interactions. Using a stringent, high-throughput yeast two-hybrid system, we tested pairwise interactions among the products of approximately 8,100 currently available Gateway-cloned open reading frames and detected approximately 2,800 interactions. This data set, called CCSB-HI1, has a verification rate of approximately 78% as revealed by an independent co-affinity purification assay, and correlates significantly with other biological attributes. The CCSB-HI1 data set increases by approximately 70% the set of available binary interactions within the tested space and reveals more than 300 new connections to over 100 disease-associated proteins. This work represents an important step towards a systematic and comprehensive human interactome project.

    Funded by: NCI NIH HHS: R33 CA132073; NHGRI NIH HHS: P50 HG004233, R01 HG001715, RC4 HG006066, U01 HG001715; NHLBI NIH HHS: U01 HL098166

    Nature 2005;437;7062;1173-8

  • Metabolic activation-related CD147-CD98 complex.

    Xu D and Hemler ME

    Dana-Farber Cancer Institute and Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA.

    Cell surface CD147 protein promotes production of matrix metalloproteinases and hyaluronan, associates with monocarboxylate transporters and integrins, and is involved in reproductive, neural, inflammatory, and tumor functions. Here we combined covalent cross-linking, mass spectrometric protein identification, and co-immunoprecipitation to show selective CD147 association with three major types of transporters (CD98 heavy chain (CD98hc)-L-type amino acid transporter, ASCT2, and monocarboxylate transporters) as well as a regulator of cell proliferation (epithelial cell adhesion molecule). In the assembly of these multicomponent complexes, CD147 and CD98hc play a central organizing role. RNA interference knock-down experiments established a strong connection between CD147 and CD98hc expression and a strong positive association of CD147 (and CD98hc) with cell proliferation. As the CD147-CD98hc complex and proliferation diminished, AMP-activated protein kinase (a cellular "fuel gauge") became activated, indicating a disturbance of cellular energy metabolism. Our data point to a CD147-CD98 cell surface supercomplex that plays a critical role in energy metabolism, likely by coordinating transport of lactate and amino acids. Furthermore we showed how covalent cross-linking, together with mass spectrometry, can be used to identify closely associated transmembrane proteins. This approach should also be applicable to many other types of transmembrane proteins besides those associated with CD98hc and CD147.

    Funded by: NCI NIH HHS: CA102034, R01 CA102034-01A2

    Molecular & cellular proteomics : MCP 2005;4;8;1061-71

  • Cell surface expression of CD147/EMMPRIN is regulated by cyclophilin 60.

    Pushkarsky T, Yurchenko V, Vanpouille C, Brichacek B, Vaisman I, Hatakeyama S, Nakayama KI, Sherry B and Bukrinsky MI

    The George Washington University Medical Center, Washington, DC 20037, USA.

    CD147, also known as extracellular matrix metalloproteinase inducer, is a regulator of matrix metalloproteinase production and also serves as a signaling receptor for extracellular cyclophilins. Previously, we demonstrated that cell surface expression of CD147 is sensitive to cyclophilin-binding drug cyclosporin A, suggesting involvement of a cyclophilin in the regulation of intracellular transport of CD147. In this report, we identify this cyclophilin as cyclophilin 60 (Cyp60), a distinct member of the cyclophilin family of proteins. CD147 co-immunoprecipitated with Cyp60, and confocal immunofluorescent microscopy revealed intracellular co-localization of Cyp60 and CD147. This interaction with Cyp60 involved proline 211 of CD147, which was shown previously to be critical for interaction between CD147 and another cyclophilin, cyclophilin A, in solution. Mutation of this proline residue abrogated co-immunoprecipitation of CD147 and Cyp60 and reduced surface expression of CD147 on the plasma membrane. Suppression of Cyp60 expression using RNA interference had an effect similar to that of cyclosporin A: reduction of cell surface expression of CD147. These results suggest that Cyp60 plays an important role in the translocation of CD147 to the cell surface. Therefore, Cyp60 may present a novel target for therapeutic interventions in diseases where CD147 functions as a pathogenic factor, such as cancer, human immunodeficiency virus infection, or rheumatoid arthritis.

    Funded by: NIAID NIH HHS: R01 AI029110; PHS HHS: R03 A1057018, R21 A1060720

    The Journal of biological chemistry 2005;280;30;27866-71

  • Basigin (CD147) is the target for organomercurial inhibition of monocarboxylate transporter isoforms 1 and 4: the ancillary protein for the insensitive MCT2 is EMBIGIN (gp70).

    Wilson MC, Meredith D, Fox JE, Manoharan C, Davies AJ and Halestrap AP

    Department of Biochemistry, University of Bristol, School of Medical Sciences, University Walk, Bristol BS8 1TD, United Kingdom.

    Translocation of monocarboxylate transporters MCT1 and MCT4 to the plasma membrane requires CD147 (basigin) with which they remain tightly associated. However, the importance of CD147 for MCT activity is unclear. MCT1 and MCT4 are both inhibited by the cell-impermeant organomercurial reagent p-chloromercuribenzene sulfonate (pCMBS). Here we demonstrate by site-directed mutagenesis that removal of all accessible cysteine residues on MCT4 does not prevent this inhibition. pCMBS treatment of cells abolished co-immunoprecipitation of MCT1 and MCT4 with CD147 and enhanced labeling of CD147 with a biotinylated-thiol reagent. This suggested that CD147 might be the target of pCMBS, and further evidence for this was obtained by treatment of cells with the bifunctional organomercurial reagent fluorescein dimercury acetate that caused oligomerization of CD147. Site-directed mutagenesis of CD147 implicated the disulfide bridge in the Ig-like C2 domain of CD147 as the target of pCMBS attack. MCT2, which is pCMBS-insensitive, was found to co-immunoprecipitate with gp70 rather than CD147. The interaction between gp70 and MCT2 was confirmed using fluorescence resonance energy transfer between the cyan fluorescent protein- and yellow fluorescent protein-tagged MCT2 and gp70. pCMBS strongly inhibited lactate transport into rabbit erythrocytes, where MCT1 interacts with CD147, but not into rat erythrocytes where it interacts with gp70. These data imply that inhibition of MCT1 and MCT4 activity by pCMBS is mediated through its binding to CD147, whereas MCT2, which associates with gp70, is insensitive to pCMBS. We conclude that ancillary proteins are required to maintain the catalytic activity of MCTs as well as for their translocation to the plasma membrane.

    The Journal of biological chemistry 2005;280;29;27213-21

  • CD147 is a regulatory subunit of the gamma-secretase complex in Alzheimer's disease amyloid beta-peptide production.

    Zhou S, Zhou H, Walian PJ and Jap BK

    Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720, USA.

    gamma-Secretase is a membrane protein complex that cleaves the beta-amyloid precursor protein (APP) within the transmembrane region, after prior processing by beta-secretase, producing amyloid beta-peptides Abeta(40) and Abeta(42). Errant production of Abeta-peptides that substantially increases Abeta(42) production has been associated with the formation of amyloid plaques in Alzheimer's disease patients. Biophysical and genetic studies indicate that presenilin-1, which contains the proteolytic active site, and three other membrane proteins [nicastrin, anterior pharynx defective-1 (APH-1), and presenilin enhancer-2 (PEN-2)] are required to form the core of the active gamma-secretase complex. Here, we report the purification of the native gamma-secretase complexes from HeLa cell membranes and the identification of an additional gamma-secretase complex subunit, CD147, a transmembrane glycoprotein with two Ig-like domains. The presence of this subunit as an integral part of the complex itself was confirmed through coimmunoprecipitation studies of the purified protein from HeLa cells and of solubilized complexes from other cell lines such as neural cell HCN-1A and HEK293. Depletion of CD147 by RNA interference was found to increase the production of Abeta peptides without changing the expression level of the other gamma-secretase components or APP substrates whereas CD147 overexpression had no statistically significant effect on Abeta-peptide production, other gamma-secretase components or APP substrates, indicating that the presence of the CD147 subunit within the gamma-secretase complex down-modulates the production of Abeta-peptides.

    Proceedings of the National Academy of Sciences of the United States of America 2005;102;21;7499-504

  • Involvement of CD147 in overexpression of MMP-2 and MMP-9 and enhancement of invasive potential of PMA-differentiated THP-1.

    Zhou J, Zhu P, Jiang JL, Zhang Q, Wu ZB, Yao XY, Tang H, Lu N, Yang Y and Chen ZN

    Department of Clinical Immunology, First Affiliated Hospital, Fourth Military Medical University, 17 Changlexilu, Xi'an 710032, Shaanxi, P.R. China. jzhou829@yahoo.com.cn

    Background: During infection and inflammation, circulating blood monocytes migrate from the intravascular compartments to the extravascular compartments, where they mature into tissue macrophages. The maturation process prepares the cells to actively participate in the inflammatory and immune responses, and many factors have been reported to be involved in the process. We found in our study that CD147 played a very important role in this process.

    Results: By using PMA-differentiated human monocyte cells line THP-1, we found that CD147 mediated matrix metalloproteinases (MMPs) expression of the leukemic THP-1 cells and thus enhanced the invasiveness of THP-1 cells. After 24 hours of PMA-induced monocyte differentiation, the mean fluorescence intensity of CD147 in differentiated THP-1 cells (289.61 +/- 31.63) was higher than that of the undifferentiated THP-1 cells (205.1 +/- 19.25). There was a significant increase of the levels of proMMP-2, proMMP-9 and their activated forms in the differentiated THP-1 cells. Invasion assays using reconstituted basement membrane showed a good correlation between the invasiveness of THP-1 cells and the production of MMP-2 and MMP-9. The difference in the MMPs expression and the invasive ability was significantly blocked by HAb18G/CD147 antagonistic peptide AP-9. The inhibitory rate of the secretion of proMMP-9 in the undifferentiated THP-1 cells was 45.07%. The inhibitory rate of the secretion of proMMP-9, the activated MMP-9 and proMMP-2 in the differentiated THP-1 cells was 52.90%, 53.79% and 47.80%, respectively. The inhibitory rate of invasive potential in the undifferentiated cells and the differentiated THP-1 cells was 41.82 % and 25.15%, respectively.

    Conclusion: The results suggest that the expression of CD147 is upregulated during the differentiation of monocyte THP-1 cells to macrophage cells, and CD147 induces the secretion and activation of MMP-2 and MMP-9 and enhances the invasive ability of THP-1 cells. The matured monocytes / macrophages, via their high expression of CD147, may play an important role in promoting the tissue repair or tissue damage during their inflammatory response.

    BMC cell biology 2005;6;1;25

  • Upstream regulation of matrix metalloproteinase by EMMPRIN; extracellular matrix metalloproteinase inducer in advanced atherosclerotic plaque.

    Yoon YW, Kwon HM, Hwang KC, Choi EY, Hong BK, Kim D, Kim HS, Cho SH, Song KS and Sangiorgi G

    Department of Internal Medicine and Cardiovascular Division, YongDong Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea.

    From experimental and clinical studies it is known that matrix conservation and degradation by matrix metalloproteinases (MMPs) plays a major role in plaque progression and destabilization with related onset of acute vascular events such as acute coronary syndromes or cerebrovascular accidents. Recently, extracellular MMPs inducer (EMMPRIN) has been reported to induce and activate the expression of MMPs in myocardium and plays an important role in the ventricular remodeling in human heart failure. Similarly to heart failure myocardium, EMMPRIN may be expressed in human atheroma and play a role in the extracellular matrix (ECM) remodeling and atherogenic cell differentiation. This study was designed to investigate the possible biological role of EMMPRIN in human atheroma. Immunohistochemical analysis for MMPs and EMMPRIN was performed on human carotid endarterectomy specimens and control aortas. EMMPRIN showed significant immunoreactivity in human atherosclerotic carotid lesions, and was colocalized with macrophage/monocyte infiltrates in atherosclerotic intima, plaque itself and vascular smooth muscle cells (VSMCs). Zymography and Western blot analysis revealed EMMPRIN expression in the carotid atheromas, but not in the control aortas. Human bone marrow monocytes, which were cultured with atherogenic proinflammatory cytokine stimulation revealed increased EMMPRIN and MMPs expressions. ECM remodeling is under the control of induction and inhibition of matrix degrading protease and the novel MMP inducer, EMMPRIN may play a role in influx and differentiation of monocytes and destabilizing atheroma.

    Atherosclerosis 2005;180;1;37-44

  • Regulation of CD147 cell surface expression: involvement of the proline residue in the CD147 transmembrane domain.

    Yurchenko V, Pushkarsky T, Li JH, Dai WW, Sherry B and Bukrinsky M

    Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461, USA.

    CD147, also known as extracellular matrix metalloproteinase inducer, is a regulator of matrix metalloproteinase production and serves as a signaling receptor for extracellular cyclophilins. Here we demonstrate that the cell surface expression of CD147 is regulated by cyclophilins via the transmembrane domain of CD147. Solution binding experiments demonstrated that the transmembrane domain was both necessary and sufficient for CD147 binding to cyclophilin A (CypA). Treatment with cyclosporin A significantly reduced surface expression of CD147 and of CD8-CD147 fusion protein carrying the extracellular domain of CD8 fused to the transmembrane and cytoplasmic domains of CD147, but did not affect expression of CD8. Peptide binding studies demonstrated specific interaction between CypA and the proline-containing peptide from the CD147 transmembrane domain. Mutation of this proline residue reduced binding of CD147-derived peptides to CypA and also diminished transport of CD147 to the plasma membrane without reducing the total level of CD147 expression. These results suggest involvement of a cyclophilin-related protein in CD147 cell surface expression and provide molecular details for regulation of CD147 trafficking by cyclophilins.

    Funded by: NIAID NIH HHS: R01 AI29110, R01 AI38245

    The Journal of biological chemistry 2005;280;17;17013-9

  • Extracellular matrix metalloproteinase inducer stimulates tumor angiogenesis by elevating vascular endothelial cell growth factor and matrix metalloproteinases.

    Tang Y, Nakada MT, Kesavan P, McCabe F, Millar H, Rafferty P, Bugelski P and Yan L

    Oncology Research, Centocor, Inc., Malvern, Pennsylvania, USA.

    Matrix metalloproteinases (MMPs) are endopeptidases that play pivotal roles in promoting tumor disease progression, including tumor angiogenesis. In many solid tumors, MMP expression could be attributed to tumor stromal cells and is partially regulated by tumor-stroma interactions via tumor cell-associated extracellular matrix metalloproteinase inducer (EMMPRIN). The role of EMMPRIN during tumor angiogenesis and growth was explored by modulating EMMPRIN expression and activity using recombinant DNA engineering and neutralizing antibodies. In human breast cancer cells, changes in EMMPRIN expression influenced vascular endothelial growth factor (VEGF) production at both RNA and protein levels. In coculture of tumor cells and fibroblasts mimicking tumor-stroma interactions, VEGF expression was induced in an EMMPRIN- and MMP-dependent fashion, and was further enhanced by overexpressing EMMPRIN. Conversely, VEGF expression was inhibited by suppressing EMMPRIN expression in tumor cells, by neutralizing EMMPRIN activity, or by inhibiting MMPs. In vivo, EMMPRIN overexpression stimulated tumor angiogenesis and growth; both were significantly inhibited by antisense suppression of EMMPRIN. Expression of both human and mouse VEGF and MMP, derived from tumor and host cells, respectively, was regulated by EMMPRIN. These results suggest a novel tumor angiogenesis mechanism in which tumor-associated EMMPRIN functionally mediates tumor-stroma interactions and directly contributes to tumor angiogenesis and growth by stimulating VEGF and MMP expression.

    Cancer research 2005;65;8;3193-9

  • Extracellular matrix metalloprotease inducer-expressing head and neck squamous cell carcinoma cells promote fibroblast-mediated type I collagen degradation in vitro.

    Rosenthal EL, Zhang W, Talbert M, Raisch KP and Peters GE

    Department of Surgery, Division of Otolaryngology/Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama 35294-0012, USA. oto@uab.edu

    Until recently, tumor progression has been considered a multistep process defined by tumor cell mutations and the importance of the surrounding stroma poorly understood. It is now recognized that matrix-degrading enzymes that promote tumor cell invasion are elaborated by both tumor cells and fibroblasts in vivo. To determine the relative role of tumor cell-derived proteases compared with fibroblast-derived proteases, coculture experiments were done with each cell type using an in vitro model of type I collagen degradation. Head and neck squamous cell carcinoma cells in coculture with normal dermal fibroblasts showed matrix degradation, but neither cell type alone produced this effect. Manipulating the in vitro coculture environment showed that collagenolysis in this model was a result of fibroblast-derived matrix metalloproteases (MMP). To explore the possible role of extracellular matrix metalloprotease inducer (EMMPRIN) in this interaction, transfection of EMMPRIN into a cell line with low endogenous EMMPRIN expression was done and showed a significant increase in collagenolysis. Inhibition of collagenolysis with a tissue inhibitor of metalloprotease-2 (TIMP-2) and a synthetic furin inhibitor was observed but not with TIMP-1, which suggested a possible role for membrane type-1 MMP. These results suggest that fibroblast-derived MMPs but not those from tumor cells are important for in vitro collagenolysis and that this process is promoted by tumor cell-expressed EMMPRIN.

    Funded by: NCPDCID CDC HHS: NCI P30 CA13148

    Molecular cancer research : MCR 2005;3;4;195-202

  • Clinicopathological significance of expression of paxillin, syndecan-1 and EMMPRIN in hepatocellular carcinoma.

    Li HG, Xie DR, Shen XM, Li HH, Zeng H and Zeng YJ

    Department of Oncology, Second Affiliated Hospital to Sun Yat-Sen University, Guangzhou 510120, Guangdong Province, China.

    Aim: To evaluate the relationship of expression of paxillin, syndecan-1 and EMMPRIN proteins with clinicopathological features in hepatocellular carcinoma (HCC).

    Methods: Fifty-one patients who underwent HCC resection were recruited in the study. Paxillin, syndecan-1 and EMMPRIN proteins in HCC tissues were detected with immunohistochemical staining.

    Results: Of 51 cases of HCC, 23 (45%) exhibited paxillin protein positive expression. Of 42 cases of adjacent non-tumor liver tissues, 24 (57%) exhibited positive expression. Positive paxillin protein expression was associated with low differentiation (r = 0.406, P = 0.004), with the presence of portal vein thrombosis (r = 0.325, P = 0.021), with extra-hepatic metastasis (r = 0.346, P = 0.014). Of 51 cases of HCC, 28 (55%) exhibited syndecan-1 protein positive expression. Of 42 cases of adjacent non-tumor liver tissues, 23 (55%) exhibited positive expression. Positive snydecan-1 protein expression was associated with well differentiation (r = 0.491, P = 0.001), with no extra-hepatic metastasis (r = 0.346, P = 0.014). Of 51 cases of HCC, 28 (55%) exhibited EMMPRIN protein positive expression. Of 42 cases of adjacent non-tumor liver tissues, 21 (50%) exhibited positive expression. Expression of EMMPRIN protein was not associated with serum AFP level, HBsAg status, presence of microsatellite nodule, tumor size, presence of cirrhosis and necrosis, differentiation, presence of portal vein thrombosis, extra-hepatic metastasis, disease-free survival and overall survival (P>0.05). Expression of paxillin protein was correlated conversely with the expression of syndecan-1 protein in HCC (r = -0.366, P = 0.010).

    Conclusion: Expression of paxillin and syndecan-1 proteins in HCC may affect its invasive and metastatic ability of the tumor. There may be a converse correlation between the expression of paxillin and syndecan-1 protein in HCC. Expression of EMMPRIN protein may be detected in HCC, but it may play little role in the invasion and metastasis of HCC.

    World journal of gastroenterology 2005;11;10;1445-51

  • Roles of the multifunctional glycoprotein, emmprin (basigin; CD147), in tumour progression.

    Yan L, Zucker S and Toole BP

    Oncology, Centocor Inc, Radnor, Pennsylvania, USA.

    Emmprin (basigin;CD147) is a widely distributed cell surface glycoprotein that belongs to the Ig superfamily and is highly enriched on the surface of malignant tumour cells. Emmprin is involved in numerous physiological and pathological systems and exhibits several molecular and cellular characteristics, but a major function of emmprin is stimulation of synthesis of several matrix metalloproteinases. In tumours, emmprin most likely stimulates matrix metalloproteinase production in stromal fibroblasts and endothelial cells as well as in tumour cells themselves by a mechanism involving homophilic interactions between emmprin molecules on apposing cells or on neighbouring cells after membrane vesicle shedding. Membrane-associated cofactors, including caveolin-1 and annexin II, regulate emmprin activity. Emmprin induces angiogenesis via stimulation of VEGF production, invasiveness via stimulation of matrix metalloproteinase production and multidrug resistance via hyaluronan-mediated up-regulation of ErbB2 signaling and cell survival pathway activities. Although the detailed mechanisms whereby it regulates these numerous phenomena are not yet known, it is clear that emmprin is a major mediator of malignant cell behavior.

    Funded by: NCI NIH HHS: CA 79866

    Thrombosis and haemostasis 2005;93;2;199-204

  • Differential expression of extracellular matrix metalloproteinase inducer (CD147) in normal and ulcerated corneas: role in epithelio-stromal interactions and matrix metalloproteinase induction.

    Gabison EE, Mourah S, Steinfels E, Yan L, Hoang-Xuan T, Watsky MA, De Wever B, Calvo F, Mauviel A and Menashi S

    Institut de Recherche sur la Peau, Hôpital St. Louis, INSERM U 532, 1 Avenue Claude Vellefaux, 75010 Paris, France. egabison@wanadoo.fr

    Extracellular matrix metalloproteinase inducer (EMMPRIN) was originally identified on the tumor cell surface as an inducer of matrix metalloproteinase (MMP) production in neighboring fibroblasts. Here we demonstrate a role for EMMPRIN in MMP induction during corneal wound healing. MMP and EMMPRIN expression was analyzed in normal and ulcerated human corneas, as well as in corneal epithelial and stromal cells in culture using confocal microscopy, zymography, immunoblots, and real-time polymerase chain reaction. In normal cornea EMMPRIN was predominantly expressed in the epithelium but was markedly induced in the anterior stroma of ulcerated corneas. This coincided with MMP-2 induction that co-localized with EMMPRIN at the epithelio-stromal boundary. The role of epithelial-stromal interaction in MMP induction was investigated in an in vitro co-culture system and demonstrated an induction and co-localization of EMMPRIN and MMP-2 in the fibroblasts at the interface with epithelial cells. Direct contact of fibroblasts with EMMPRIN-containing purified epithelial cell membranes also induced MMP-1, MMP-2, and EMMPRIN and this was inhibited by a blocking anti-EMMPRIN antibody, suggesting that EMMPRIN was primarily responsible for this induction. These findings, and the up-regulation of EMMPRIN by epidermal growth factor and transforming growth factor-beta, demonstrate a role for EMMPRIN in wound healing and suggest that sustained local up-regulation of EMMPRIN and MMPs in chronic situations in which healing is delayed may lead to excessive matrix degradation and corneal melts.

    The American journal of pathology 2005;166;1;209-19

  • Expression of CD147 on monocytes/macrophages in rheumatoid arthritis: its potential role in monocyte accumulation and matrix metalloproteinase production.

    Zhu P, Ding J, Zhou J, Dong WJ, Fan CM and Chen ZN

    Department of Clinical Immunology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China. zhuping@fmmu.edu.cn

    Monocytes/macrophages play an important role in rheumatoid arthritis (RA) pathogenesis. They can activate fibroblasts through many molecules, including IL-1 and tumor necrosis factor-alpha, but there have been very few reports on the role of CD147 in RA. In our study, the results of flow cytometry reveal that the mean fluorescence intensity (MFI) of CD147 expression on CD14+ monocytes of peripheral blood from RA patients was higher than that in normal control and ankylosing spondylitis (AS) patients. The MFI of CD147 expression on the CD14+ monocytes in RA synovial fluid was higher than that in RA peripheral blood. Immunohistochemical staining shows that CD147 expression in RA synovium correlated with matrix metalloproteinase (MMP)-1 expression. A double immunofluorescent assay shows that CD147 was expressed on CD68+ cells in RA synovium. The potential role of CD147 in cyclophilin A (CyPA)-mediated cell migration was studied using a chemotaxis assay in vitro and it was found that the addition of anti-CD147 antibody or a CD147 antagonistic peptide significantly decreased the chemotactic index of the mononuclear cells. The role of CD147 in MMP production and cell invasion in vitro were studied through the co-culture of human CD14+ monocytes or monocytic line THP-1 cells and human fibroblasts, as well as by gel zymography and an invasion assay. Significantly elevated release and activation of MMP-9 and/or MMP-2 were seen in the co-culture of human monocytes/THP-1 cells and fibroblasts compared with cultures of the cells alone. An increased number of cells invading through the filters in the invasion assays was also observed in the co-cultured cells. The addition of CD147 antagonistic peptide had some inhibitory effect, not only on MMP production but also on cell invasion in the co-culture. Our study demonstrates that the increased expression of CD147 on monocytes/macrophages in RA may be responsible for elevated MMP secretion, cell invasion and CyPA-mediated cell migration into the joints, all of which may contribute to the cartilage and bone destruction of RA. These findings, together with a better understanding of CD147, CyPA and RA, will help in the development of innovative therapeutic interventions for RA.

    Arthritis research & therapy 2005;7;5;R1023-33

  • The functional interaction between CD98 and CD147 in regulation of virus-induced cell fusion and osteoclast formation.

    Mori K, Nishimura M, Tsurudome M, Ito M, Nishio M, Kawano M, Kozuka Y, Yamashita Y, Komada H, Uchida A and Ito Y

    Department of Microbiology, Mie University School of Medicine, 2-174 Edobashi, Tsu-Shi, 514-8507 Mie Prefecture, Japan.

    Membrane fusion is an important event in the functioning of a living organism. Life starts as a sperm fuses with the membrane of an egg, leading to its fertilization. Membrane fusion is also required for myogenesis, osteogenesis and placenta formation. Multinucleated giant cells originating from monocytes-macrophages are associated with granulomatous lesions formed in response to foreign bodies, viruses, and bacteria. The CD4 molecule acts as a receptor for HIV. The major virus envelope glycoprotein, gp120, attaches to CD4 molecules expressed on the host cell surface. After binding to CD4 on the target cells, HIV is internalized via direct, pH-independent fusion of the viral and cell membranes. However, attachment of HIV to CD4 on the target cells is not sufficient for fusion. Interaction of gp160-expressing cells with neighboring cells bearing surface CD4 molecules is also required for syncytium formation. Syncytium formation and subsequent generalized cell fusion have been reported as potentially important mechanisms of virus-induced cytotoxic effects. Some antibodies against CD98/FRP-1 suppressed virus-induced cell fusion and CD98-mediated cell fusion of monocytes, indicating that CD98/FRP-1 molecules are able to regulate cell fusion. In this study, the functional interaction between CD98 and CD147 was investigated. Three kinds (Ab1, 2, and 3) of anti-CD147 and three kinds of anti-CD98 antibodies were used. Ab1 suppressed CD98-mediated cell fusion, but showed no effect on cell aggregation of Cd(+)U2ME-7 cells, U937-2 cells expressing HIV gp160. On the other hand, Ab2 enhanced the CD98-mediated cell fusion. Ab1 showed suppressive effect at early stage and Ab2 showed enhancing effect at later stage. Ab2 and 3 suppressed the spontaneous cell agglutination and cell fusion of Cd(+)JME-2 cells, Jurkat cells expressing HIV gp160. Ab2 suppressed CD98-mediated cell fusion, but showed no effect on cell aggregation of Cd(+)JME-2 cells. Ab2 cancelled suppression of cell fusion induced by suppressive antibody against CD98. Ab2 and 3 also suppressed CD98-mediated cell fusion of monocytes. This study indicates the functional interaction between CD98 and CD147 in the regulation of cell fusion.

    Medical microbiology and immunology 2004;193;4;155-62

  • The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

    Gerhard DS, Wagner L, Feingold EA, Shenmen CM, Grouse LH, Schuler G, Klein SL, Old S, Rasooly R, Good P, Guyer M, Peck AM, Derge JG, Lipman D, Collins FS, Jang W, Sherry S, Feolo M, Misquitta L, Lee E, Rotmistrovsky K, Greenhut SF, Schaefer CF, Buetow K, Bonner TI, Haussler D, Kent J, Kiekhaus M, Furey T, Brent M, Prange C, Schreiber K, Shapiro N, Bhat NK, Hopkins RF, Hsie F, Driscoll T, Soares MB, Casavant TL, Scheetz TE, Brown-stein MJ, Usdin TB, Toshiyuki S, Carninci P, Piao Y, Dudekula DB, Ko MS, Kawakami K, Suzuki Y, Sugano S, Gruber CE, Smith MR, Simmons B, Moore T, Waterman R, Johnson SL, Ruan Y, Wei CL, Mathavan S, Gunaratne PH, Wu J, Garcia AM, Hulyk SW, Fuh E, Yuan Y, Sneed A, Kowis C, Hodgson A, Muzny DM, McPherson J, Gibbs RA, Fahey J, Helton E, Ketteman M, Madan A, Rodrigues S, Sanchez A, Whiting M, Madari A, Young AC, Wetherby KD, Granite SJ, Kwong PN, Brinkley CP, Pearson RL, Bouffard GG, Blakesly RW, Green ED, Dickson MC, Rodriguez AC, Grimwood J, Schmutz J, Myers RM, Butterfield YS, Griffith M, Griffith OL, Krzywinski MI, Liao N, Morin R, Morrin R, Palmquist D, Petrescu AS, Skalska U, Smailus DE, Stott JM, Schnerch A, Schein JE, Jones SJ, Holt RA, Baross A, Marra MA, Clifton S, Makowski KA, Bosak S, Malek J and MGC Project Team

    The National Institutes of Health's Mammalian Gene Collection (MGC) project was designed to generate and sequence a publicly accessible cDNA resource containing a complete open reading frame (ORF) for every human and mouse gene. The project initially used a random strategy to select clones from a large number of cDNA libraries from diverse tissues. Candidate clones were chosen based on 5'-EST sequences, and then fully sequenced to high accuracy and analyzed by algorithms developed for this project. Currently, more than 11,000 human and 10,000 mouse genes are represented in MGC by at least one clone with a full ORF. The random selection approach is now reaching a saturation point, and a transition to protocols targeted at the missing transcripts is now required to complete the mouse and human collections. Comparison of the sequence of the MGC clones to reference genome sequences reveals that most cDNA clones are of very high sequence quality, although it is likely that some cDNAs may carry missense variants as a consequence of experimental artifact, such as PCR, cloning, or reverse transcriptase errors. Recently, a rat cDNA component was added to the project, and ongoing frog (Xenopus) and zebrafish (Danio) cDNA projects were expanded to take advantage of the high-throughput MGC pipeline.

    Funded by: PHS HHS: N01-C0-12400

    Genome research 2004;14;10B;2121-7

  • Signal peptide prediction based on analysis of experimentally verified cleavage sites.

    Zhang Z and Henzel WJ

    Department of Bioinformatics, Genentech, Inc., South San Francisco, CA 94080, USA. zemin@gene.com

    A number of computational tools are available for detecting signal peptides, but their abilities to locate the signal peptide cleavage sites vary significantly and are often less than satisfactory. We characterized a set of 270 secreted recombinant human proteins by automated Edman analysis and used the verified cleavage sites to evaluate the success rate of a number of computational prediction programs. An examination of the frequency of amino acid in the N-terminal region of the data set showed a preference of proline and glutamine but a bias against tyrosine. The data set was compared to the SWISS-PROT database and revealed a high percentage of discrepancies with cleavage site annotations that were computationally generated. The best program for predicting signal sequences was found to be SignalP 2.0-NN with an accuracy of 78.1% for cleavage site recognition. The new data set can be utilized for refining prediction algorithms, and we have built an improved version of profile hidden Markov model for signal peptides based on the new data.

    Protein science : a publication of the Protein Society 2004;13;10;2819-24

  • Links between CD147 function, glycosylation, and caveolin-1.

    Tang W, Chang SB and Hemler ME

    Dana-Farber Cancer Institute and Department of Pathology, Harvard Medical School, Boston, MA 02115, USA.

    Cell surface CD147 shows remarkable variations in size (31-65 kDa) because of heterogeneous N-glycosylation, with the most highly glycosylated forms functioning to induce matrix metalloproteinase (MMP) production. Here we show that all three CD147 N-glycosylation sites make similar contributions to both high and low glycoforms (HG- and LG-CD147). l-Phytohemagglutinin lectin binding and swainsonine inhibition experiments indicated that HG-CD147 contains N-acetylglucosaminyltransferase V-catalyzed, beta1,6-branched, polylactosamine-type sugars, which account for its excess size. Therefore, CD147, which is itself elevated on invasive tumor cells, may make a major contribution to the abundance of beta1,6-branched polylactosamine sugars that appear on invasive tumor cells. It was shown previously that caveolin-1 associates with CD147, thus inhibiting CD147 self-aggregation and MMP induction; now we show that caveolin-1 associates with LG-CD147 and restricts the biosynthetic conversion of LG-CD147 to HG-CD147. In addition, HG-CD147 (but not LG-CD147) was preferentially captured as a multimer after treatment of cells with a homobifunctional cross-linking agent and was exclusively recognized by monoclonal antibody AAA6, a reagent that selectively recognizes self-associated CD147 and inhibits CD147-mediated MMP induction. In conclusion, we have 1) determined the biochemical basis for the unusual size variation in CD147, 2) established that CD147 is a major carrier of beta1,6-branched polylactosamine sugars on tumor cells, and 3) determined that caveolin-1 can inhibit the conversion of LG-CD147 to HG-CD147. Because it is HG-CD147 that self-aggregates and stimulates MMP induction, we now have a mechanism to explain how caveolin-1 inhibits these processes. These results help explain the previously established tumor suppressor functions of caveolin-1.

    Funded by: NCI NIH HHS: CA-86712

    Molecular biology of the cell 2004;15;9;4043-50

  • Expression of extracellular matrix metalloproteinase inducer in human placenta and fetal membranes at term labor.

    Li W, Alfaidy N and Challis JR

    Canadian Institutes of Health Research Group in Fetal and Neonatal Health and Development, Department of Physiology, University of Toronto, Toronto, Ontario, Canada M5S 1A8. weisun.li@utoronto.ca

    Matrix metalloproteinases (MMPs) are the main mediators of extracellular matrix (ECM) degradation during human parturition. However, the mechanisms involved in regulation of MMP production during parturition remain poorly understood. Recently, an extracellular matrix metalloproteinase inducer (EMMPRIN) has been shown to play a key role, as a local regulator, in stimulating MMP production in cancer systems. Whether EMMPRIN is expressed and stimulates MMP production in human placenta and fetal membranes is presently unknown. In this study, we investigated the expression of EMMPRIN at the levels of mRNA and protein in human term placenta and fetal membranes with or without labor. Western blot analysis showed that EMMPRIN protein was detected in term placenta and fetal membranes at two molecular masses of 40 and 65 kDa (glycosylated protein) and one of approximately 30 kDa (nonglycosylated protein). The ratio of 65 kDa EMMPRIN to total EMMPRIN significantly increased (P < 0.05) in term labor chorio-decidua and amnion compared with nonlabor chorio-decidua and amnion. Immunohistochemical analysis revealed that EMMPRIN was expressed in placental syncytiotrophoblast, amniotic epithelial cells, trophoblast cells of chorion laeve, and decidua parietalis. EMMPRIN was also detected at the mRNA level using RT-PCR in cultured placental syncytiotrophoblast, amniotic epithelial cells, and chorionic trophoblast cells. We conclude that human placenta and fetal membranes express EMMPRIN, with the potential to stimulate MMP production, thereby facilitating fetal membrane rupture and leading to detachment of the placenta and fetal membranes from the maternal uterus at the time of parturition.

    The Journal of clinical endocrinology and metabolism 2004;89;6;2897-904

  • Expression of extracellular matrix metalloproteases inducer on micrometastatic and primary mammary carcinoma cells.

    Reimers N, Zafrakas K, Assmann V, Egen C, Riethdorf L, Riethdorf S, Berger J, Ebel S, Jänicke F, Sauter G and Pantel K

    Institute of Tumor Biology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.

    Purpose: EMMPRIN (extracellular matrix metalloprotease inducer) is a glycosylated member of the immunoglobulin superfamily known to stimulate the production of matrix metalloproteases (MMPs) 1, 2, and 3 and MT1-MMP in peritumoral fibroblasts. We here evaluated whether EMMPRIN expression is related to tumor progression in human breast cancer.

    An immunohistochemical study using high-density tissue microarrays (n = 2222 breast cancer samples) and EMMPRIN-specific antibodies HIM6 and MEM-M6/1 was performed, and staining results were statistically correlated with various clinicopathological parameters. To analyze the putative association between EMMPRIN expression and bone marrow (BM) micrometastasis, an additional set of 55 breast tumors from patients with or without micrometastatic cells as determined with anti-cytokeratin antibody A45-B/B3 were included in our study. Cytokeratin-positive cells in BM were costained with EMMPRIN-specific antibody 1G6.2.

    Results: Positive EMMPRIN staining correlated significantly with various histopathological risk factors (higher tumor grade, increased tumor size, negative estrogen receptor status and progesterone receptor status, and higher mitotic index) as well as decreased tumor-specific survival (log-rank, P = 0.0027). In particular, in patients > 50 years (i.e., postmenopausal women), EMMPRIN expression was an independent prognosticator as shown by Cox regression analysis (relative risk = 1.7, 95% confidence interval 1.4-4.3, P = 0.036). An involvement of EMMPRIN in tumor progression was also supported by the fact that it was expressed on approximately 90% of micrometastatic cells in BM.

    Conclusions: EMMPRIN expression in primary tumor predicts an unfavorable prognosis in breast cancer, suggesting a crucial role of EMMPRIN in progression of human mammary carcinomas.

    Clinical cancer research : an official journal of the American Association for Cancer Research 2004;10;10;3422-8

  • The DNA sequence and biology of human chromosome 19.

    Grimwood J, Gordon LA, Olsen A, Terry A, Schmutz J, Lamerdin J, Hellsten U, Goodstein D, Couronne O, Tran-Gyamfi M, Aerts A, Altherr M, Ashworth L, Bajorek E, Black S, Branscomb E, Caenepeel S, Carrano A, Caoile C, Chan YM, Christensen M, Cleland CA, Copeland A, Dalin E, Dehal P, Denys M, Detter JC, Escobar J, Flowers D, Fotopulos D, Garcia C, Georgescu AM, Glavina T, Gomez M, Gonzales E, Groza M, Hammon N, Hawkins T, Haydu L, Ho I, Huang W, Israni S, Jett J, Kadner K, Kimball H, Kobayashi A, Larionov V, Leem SH, Lopez F, Lou Y, Lowry S, Malfatti S, Martinez D, McCready P, Medina C, Morgan J, Nelson K, Nolan M, Ovcharenko I, Pitluck S, Pollard M, Popkie AP, Predki P, Quan G, Ramirez L, Rash S, Retterer J, Rodriguez A, Rogers S, Salamov A, Salazar A, She X, Smith D, Slezak T, Solovyev V, Thayer N, Tice H, Tsai M, Ustaszewska A, Vo N, Wagner M, Wheeler J, Wu K, Xie G, Yang J, Dubchak I, Furey TS, DeJong P, Dickson M, Gordon D, Eichler EE, Pennacchio LA, Richardson P, Stubbs L, Rokhsar DS, Myers RM, Rubin EM and Lucas SM

    Stanford Human Genome Center, Department of Genetics, Stanford University School of Medicine, 975 California Avenue, Palo Alto, California 94304, USA. jane@shgc.stanford.edu

    Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.

    Nature 2004;428;6982;529-35

  • Caveolin-1 regulates matrix metalloproteinases-1 induction and CD147/EMMPRIN cell surface clustering.

    Tang W and Hemler ME

    Dana-Farber Cancer Institute and Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA.

    CD147, a regulator of matrix metalloproteinase (MMP) production, showed highly specific association with caveolin-1 on the surface of multiple cell types. CD147-caveolin-1 complex formation was temperature and cholesterol dependent, reminiscent of associations seen within caveolae/lipid rafts. However, the subset of caveolin-1 associated with CD147 appeared exclusively within intermediate density sucrose gradient fractions, rather than in the low density fractions containing the bulk of caveolin-1. Mutagenesis experiments revealed that CD147 Ig domain 2 was required for caveolin-1 association. In contrast to CD147-caveolin-1 complexes, CD147-alpha(3) integrin association was not disrupted upon cholesterol depletion, occurred in high density sucrose fractions, and did not involve CD147 Ig domain 2. Overexpression of caveolin-1 caused a specific decrease in clustering of cell surface CD147, as detected by "cluster specific" mAb M6/13. Conversely, a mutant CD147 deficient in caveolin-1 association showed enhanced spontaneous cell surface clustering (detected by mAb M6/13), and did not show decreased clustering in response to caveolin-1 overexpression. Furthermore, the same CD147 mutant yielded an elevated induction of MMP-1. In conclusion, caveolin-1 associates with CD147, in a complex distinct from CD147-alpha(3) integrin complexes, thereby diminishing both CD147 clustering and CD147-dependent MMP-1-inducing activity.

    Funded by: NCI NIH HHS: CA86712

    The Journal of biological chemistry 2004;279;12;11112-8

  • Direct cell-cell interaction enhances pro-MMP-2 production and activation in co-culture of laryngeal cancer cells and fibroblasts: involvement of EMMPRIN and MT1-MMP.

    Suzuki S, Sato M, Senoo H and Ishikawa K

    Department of Otolaryngology, Akita University School of Medicine, Akita 010-8543, Japan. shinsuke@med.akita-u.ac.jp

    Matrix metalloproteinases-2 (MMP-2, gelatinase A) has been regarded as a crucial enzyme for tumor progression, invasion, and metastasis by its capability to degrade the basement membrane components, and its activation process is critical for tumor development. Recently, EMMPRIN/CD147, which is a member of immunoglobulin superfamily, has been reported to be highly expressed in tumor cells and induce production of MMPs from fibroblasts adjacent to the tumor cells. In this study, we demonstrated that production of pro- and active forms of MMP-2 by human dermal fibroblasts was enhanced by the direct cell-cell contact with co-cultured HEp-2 cells derived from a human laryngeal epidermoid carcinoma. The results from immunoblotting and reverse transcription-polymerase chain reaction (RT-PCR) analysis indicated that HEp-2 cells express a higher level of EMMPRIN but only a low level of MMP-2 and membrane type 1-matrix metalloproteinase (MT1-MMP), whereas fibroblasts express a higher level of MMP-2 and MT1-MMP and a low level of EMMPRIN. In a mixed co-culture with direct cell-cell contacts, co-cultured HEp-2 cells stimulated the pro- and active MMP-2 production from fibroblasts, but not in a separated co-culture through polycarbonate membrane. Production of pro/active MMP-2 and MT1-MMP (activator of pro-MMP-2) in fibroblasts was induced by the addition of membrane fractions prepared from HEp-2 cells to the fibroblast culture, and the induction was suppressed by the EMMPRIN depletion after immunoprecipitation, signifying the participation of EMMPRIN for the induction and activation of MMP-2. Our results suggest an importance of the direct cell-cell interaction involving EMMPRIN rather than humoral factors such as cytokines for pro-MMP-2 production and activation followed by tumor progression, invasion, and metastasis in laryngeal cancer.

    Experimental cell research 2004;293;2;259-66

  • Tumor-stroma interaction: positive feedback regulation of extracellular matrix metalloproteinase inducer (EMMPRIN) expression and matrix metalloproteinase-dependent generation of soluble EMMPRIN.

    Tang Y, Kesavan P, Nakada MT and Yan L

    Oncology Research, Centocor, Inc., Malvern, PA 19087, USA.

    Matrix metalloproteinases (MMPs) are metal-dependent endopeptidases that play pivotal roles in tumor disease progression. In many solid tumors, MMPs are indeed produced by tumor stromal cells, rather than by tumor cells. This expression pattern is, at least in part, regulated by tumor-stroma interaction via tumor cell-associated extracellular matrix metalloproteinase inducer (EMMPRIN). In vitro, recombinant EMMPRIN dose-dependently stimulated MMP-1 production by primary human fibroblast cells. Interestingly, in addition to stimulating MMP expression, EMMPRIN also induced its own gene expression. To further explore this potential positive feedback regulatory mechanism, we generated human breast cancer cells expressing different levels of EMMPRIN. Coculture of EMMPRIN-positive tumor cells with fibroblast cells resulted in a concomitant stimulation of MMP-2, MMP-9, and EMMPRIN production. This induction was EMMPRIN dependent, was further enhanced by overexpression, and was reduced by antisense suppression of EMMPRIN expression in tumor cells. Increased expression of membrane-associated EMMPRIN was accompanied by an MMP-dependent generation of a soluble form of EMMPRIN representing a proteolytic cleavage product lacking the carboxyl terminus. On the basis of these findings, we propose a model in which tumor cell-associated EMMPRIN stimulates MMPs, as well as EMMPRIN expression in tumor stroma. Increased MMP activity in tumor local environment results in proteolytic cleavage of membrane-associated EMMPRIN, releasing soluble EMMPRIN. Soluble EMMPRIN in turn acts in a paracrine fashion on stroma cells that are both adjacent and distant to tumor sites to further stimulate the production of MMPs and additional EMMPRIN, which consequently contributes to tumor angiogenesis, tumor growth, and metastasis.

    Molecular cancer research : MCR 2004;2;2;73-80

  • The microvesicle as a vehicle for EMMPRIN in tumor-stromal interactions.

    Sidhu SS, Mengistab AT, Tauscher AN, LaVail J and Basbaum C

    Biomolecular Sciences Program, Cardiovascular Research Institute and Department of Anatomy, UCSF, San Francisco, CA 94143, USA.

    EMMPRIN is a transmembrane glycoprotein expressed at high levels by tumor cells. It has been identified as a tumor-derived factor that can stimulate matrix metalloproteinase expression in fibroblasts and hence facilitate tumor invasion and metastasis. Recent studies have shown that full-length EMMPRIN is released by tumor cells, but the mechanism of release remains unclear. Here, we show that EMMPRIN is released from the surface of NCI-H460 cells via microvesicle shedding. However, these vesicles are unstable and rapidly break down to release bioactive EMMPRIN. Although microvesicle shedding has been considered a constitutive process in tumor cells, our data show that it can be amplified upon cell exposure to PMA, elucidating at least one signalling cascade responsible for EMMPRIN release. This pathway is dependent on protein kinase C, calcium mobilization and mitogen-activated protein kinase kinase (MEK 1/2). Thus, the results outline a novel form of tumor-stromal interaction in which extracellular matrix degradation by fibroblasts is controlled through the microvesicular release of EMMPRIN from tumor cells.

    Funded by: NHLBI NIH HHS: P0-1 HL24136, R0-1 HL 43762

    Oncogene 2004;23;4;956-63

  • Complete sequencing and characterization of 21,243 full-length human cDNAs.

    Ota T, Suzuki Y, Nishikawa T, Otsuki T, Sugiyama T, Irie R, Wakamatsu A, Hayashi K, Sato H, Nagai K, Kimura K, Makita H, Sekine M, Obayashi M, Nishi T, Shibahara T, Tanaka T, Ishii S, Yamamoto J, Saito K, Kawai Y, Isono Y, Nakamura Y, Nagahari K, Murakami K, Yasuda T, Iwayanagi T, Wagatsuma M, Shiratori A, Sudo H, Hosoiri T, Kaku Y, Kodaira H, Kondo H, Sugawara M, Takahashi M, Kanda K, Yokoi T, Furuya T, Kikkawa E, Omura Y, Abe K, Kamihara K, Katsuta N, Sato K, Tanikawa M, Yamazaki M, Ninomiya K, Ishibashi T, Yamashita H, Murakawa K, Fujimori K, Tanai H, Kimata M, Watanabe M, Hiraoka S, Chiba Y, Ishida S, Ono Y, Takiguchi S, Watanabe S, Yosida M, Hotuta T, Kusano J, Kanehori K, Takahashi-Fujii A, Hara H, Tanase TO, Nomura Y, Togiya S, Komai F, Hara R, Takeuchi K, Arita M, Imose N, Musashino K, Yuuki H, Oshima A, Sasaki N, Aotsuka S, Yoshikawa Y, Matsunawa H, Ichihara T, Shiohata N, Sano S, Moriya S, Momiyama H, Satoh N, Takami S, Terashima Y, Suzuki O, Nakagawa S, Senoh A, Mizoguchi H, Goto Y, Shimizu F, Wakebe H, Hishigaki H, Watanabe T, Sugiyama A, Takemoto M, Kawakami B, Yamazaki M, Watanabe K, Kumagai A, Itakura S, Fukuzumi Y, Fujimori Y, Komiyama M, Tashiro H, Tanigami A, Fujiwara T, Ono T, Yamada K, Fujii Y, Ozaki K, Hirao M, Ohmori Y, Kawabata A, Hikiji T, Kobatake N, Inagaki H, Ikema Y, Okamoto S, Okitani R, Kawakami T, Noguchi S, Itoh T, Shigeta K, Senba T, Matsumura K, Nakajima Y, Mizuno T, Morinaga M, Sasaki M, Togashi T, Oyama M, Hata H, Watanabe M, Komatsu T, Mizushima-Sugano J, Satoh T, Shirai Y, Takahashi Y, Nakagawa K, Okumura K, Nagase T, Nomura N, Kikuchi H, Masuho Y, Yamashita R, Nakai K, Yada T, Nakamura Y, Ohara O, Isogai T and Sugano S

    Helix Research Institute, 1532-3 Yana, Kisarazu, Chiba 292-0812, Japan.

    As a base for human transcriptome and functional genomics, we created the "full-length long Japan" (FLJ) collection of sequenced human cDNAs. We determined the entire sequence of 21,243 selected clones and found that 14,490 cDNAs (10,897 clusters) were unique to the FLJ collection. About half of them (5,416) seemed to be protein-coding. Of those, 1,999 clusters had not been predicted by computational methods. The distribution of GC content of nonpredicted cDNAs had a peak at approximately 58% compared with a peak at approximately 42%for predicted cDNAs. Thus, there seems to be a slight bias against GC-rich transcripts in current gene prediction procedures. The rest of the cDNAs unique to the FLJ collection (5,481) contained no obvious open reading frames (ORFs) and thus are candidate noncoding RNAs. About one-fourth of them (1,378) showed a clear pattern of splicing. The distribution of GC content of noncoding cDNAs was narrow and had a peak at approximately 42%, relatively low compared with that of protein-coding cDNAs.

    Nature genetics 2004;36;1;40-5

  • Identification and characterization of extracellular matrix metalloproteinase inducer in human endometrium during the menstrual cycle in vivo and in vitro.

    Noguchi Y, Sato T, Hirata M, Hara T, Ohama K and Ito A

    Department of Biochemistry and Molecular Biology, School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan.

    Extracellular matrix metalloproteinase inducer (EMMPRIN) participates in the breakdown of the extracellular matrix (ECM) by augmenting matrix metalloproteinase (MMP) expression. In the present study, we identified and characterized the menstrual cycle-dependent expression of EMMPRIN in human endometrium in vivo. At the proliferative phase of the menstrual cycle, EMMPRIN was detected in glandular epithelium of the basal layer in endometrium. In addition, at the superficial region of the functional layer, EMMPRIN was expressed in stroma but not glandular epithelium. At the secretory phase, EMMPRIN was found in both stroma and glandular epithelium of the functional layer and glandular epithelium of the basal layer. Furthermore, EMMPRIN colocalized with MMP-1/collagenase-1 in the glandular epithelium in vivo. Western blot analysis of tissue from the functional layer showed that EMMPRIN species with molecular weights of approximately 35 and 47 kDa were detected at the proliferative phase, whereas approximately 35- and 51-kDa EMMPRIN species were predominantly expressed at the secretory phase. In addition, the variant EMMPRIN molecules were found to differ in glycosylation. On the other hand, EMMPRIN was constitutively produced in primary cultured endometrial stromal and glandular epithelial cells. The production and glycosylation of EMMPRIN in the stromal cells were augmented by progesterone at the posttranscriptional and posttranslational stages, respectively. These results suggest for the first time that EMMPRIN is expressed in human endometrium during the menstrual cycle and that its expression and glycosylation are augmented by progesterone. Moreover, EMMPRIN may be involved in ECM breakdown at the interface between endometrial cells and ECM by using EMMPRIN-bound MMP-1.

    The Journal of clinical endocrinology and metabolism 2003;88;12;6063-72

  • The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment.

    Clark HF, Gurney AL, Abaya E, Baker K, Baldwin D, Brush J, Chen J, Chow B, Chui C, Crowley C, Currell B, Deuel B, Dowd P, Eaton D, Foster J, Grimaldi C, Gu Q, Hass PE, Heldens S, Huang A, Kim HS, Klimowski L, Jin Y, Johnson S, Lee J, Lewis L, Liao D, Mark M, Robbie E, Sanchez C, Schoenfeld J, Seshagiri S, Simmons L, Singh J, Smith V, Stinson J, Vagts A, Vandlen R, Watanabe C, Wieand D, Woods K, Xie MH, Yansura D, Yi S, Yu G, Yuan J, Zhang M, Zhang Z, Goddard A, Wood WI, Godowski P and Gray A

    Departments of Bioinformatics, Molecular Biology and Protein Chemistry, Genentech, Inc, South San Francisco, California 94080, USA. hclark@gene.com

    A large-scale effort, termed the Secreted Protein Discovery Initiative (SPDI), was undertaken to identify novel secreted and transmembrane proteins. In the first of several approaches, a biological signal sequence trap in yeast cells was utilized to identify cDNA clones encoding putative secreted proteins. A second strategy utilized various algorithms that recognize features such as the hydrophobic properties of signal sequences to identify putative proteins encoded by expressed sequence tags (ESTs) from human cDNA libraries. A third approach surveyed ESTs for protein sequence similarity to a set of known receptors and their ligands with the BLAST algorithm. Finally, both signal-sequence prediction algorithms and BLAST were used to identify single exons of potential genes from within human genomic sequence. The isolation of full-length cDNA clones for each of these candidate genes resulted in the identification of >1000 novel proteins. A total of 256 of these cDNAs are still novel, including variants and novel genes, per the most recent GenBank release version. The success of this large-scale effort was assessed by a bioinformatics analysis of the proteins through predictions of protein domains, subcellular localizations, and possible functional roles. The SPDI collection should facilitate efforts to better understand intercellular communication, may lead to new understandings of human diseases, and provides potential opportunities for the development of therapeutics.

    Genome research 2003;13;10;2265-70

  • Retina-specific expression of 5A11/Basigin-2, a member of the immunoglobulin gene superfamily.

    Ochrietor JD, Moroz TP, van Ekeris L, Clamp MF, Jefferson SC, deCarvalho AC, Fadool JM, Wistow G, Muramatsu T and Linser PJ

    Whitney Laboratory of the University of Florida, St. Augustine, Florida 32080, USA. jdo@whitney.ufl.edu

    Purpose: 5A11/Basigin has recently been identified as a critical glycoprotein for full maturity and function of the mouse retina. However, the biological function of 5A11/Basigin has yet to be determined. Previous reports indicate the presence of multiple 5A11/Basigin polypeptides within the retina. Therefore, in an effort to determine the function of 5A11/Basigin, the molecular diversity of its expression was evaluated.

    Methods: Northern blot and immunoblot techniques were used to evaluate the number of forms of 5A11/Basigin in the mouse retina. cDNA cloning, using a mouse retina library or RT-PCR from rat, chicken, zebrafish, and human retina, was performed to determine the sequence of 5A11/Basigin transcripts. A peptide was generated, based on the deduced amino acid sequence, for subsequent antibody production. Localization of 5A11/Basigin expression was evaluated by immunoblot, immunohistochemistry, and real-time RT-PCR.

    Results: Two 5A11/Basigin transcripts of approximately 1.5 kb and approximately 1.8 kb, which correspond to glycosylated proteins of approximately 45 and approximately 55 kDa, respectively, were identified in mouse retina. The shorter form was previously cloned. However, the longer form, a splice variant of mouse 5A11/Basigin, is a member of the immunoglobulin gene superfamily and has been named 5A11/Basigin-2. Homologous transcripts were also cloned from rat, chicken, zebrafish, and human retina. 5A11/Basigin-2 expression was limited to the retina, specifically to photoreceptor cells, where it appeared to be most concentrated in the inner segments.

    Conclusions: The specific and limited expression of 5A11/Basigin-2 explicitly within photoreceptor cells implies that this glycoprotein plays a fundamental role within the retina. However, its role remains to be determined.

    Funded by: NEI NIH HHS: EY13020, F32EY13918

    Investigative ophthalmology & visual science 2003;44;9;4086-96

  • Expression and localization of extracellular matrix metalloproteinase inducer in giant cell tumor of bone.

    Si AI, Huang L, Xu J, Kumta SM, Wood D and Zheng MH

    Department of Orthopaedic Surgery, University of Western Australia, Nedlands, WA. [corrected].

    Matrix metalloproteinases (MMPs) are regarded as a significant regulator in tumor invasion and metastasis. Previous studies have shown that extracellular matrix metalloproteinase inducer (EMMPRIN) in tumor cells induces the synthesis of MMPs. EMMPRIN is abundantly present on the surface of tumor cells and stimulate adjacent stromal cells to synthesize MMPs to induce tumor progression. Giant cell tumor (GCT) of bone is a benign but locally aggressive primary neoplasm of bone. The spindle-shaped mononuclear stromal cells are considered to be the tumor components of GCT, which are capable of inducing osteoclast formation by recruiting the circulating monocyte and macrophage. In this study, we proposed that EMMPRIN is associated with the biological progression and aggressiveness of GCT. We have conducted semi-quantitative RT-PCR to determine the correlation of EMMPRIN expression with the clinical stage of GCT. We have also examined the cellular localization of EMMPRIN in GCT using in-situ hybridization (ISH) and Immunohistochemistry (IH). The results showed that EMMPRIN was present in GCT and its mRNA levels were associated with the clinical stage of GCT. Higher expression level of EMMPRIN was observed in GCT with advanced stage (stage III). There was a great significance (P < 0.05) of EMMPRIN expression between stage I & II and stage III GCTs. Both ISH and IH demonstrated that EMMPRIN is present at the multinuclear osteoclast-like giant cells of GCT, with strong immunostaining on the cell membrane. The stromal-like tumor cells were also positively stained but the intensity was weaker. Interestingly, the production of EMMPRIN in osteoclast-like cells of GCT seems to be regulated by stromal-like tumor cells. Receptor activator of NF-kappaB ligand (RANKL), which has been previously shown to be produced by the stromal-like tumor cells for the recruitment of osteoclast-like giant cells in GCT, enhanced the expression of EMMPRIN mRNA during the differentiation of macrophage-like RAW(264.7) cells into osteoclasts. In short, our studies suggest that EMMPRIN may be an important regulatory factor involved in the biological behaviors of GCT.

    Journal of cellular biochemistry 2003;89;6;1154-63

  • Selective inhibition of T cell activation via CD147 through novel modulation of lipid rafts.

    Staffler G, Szekeres A, Schütz GJ, Säemann MD, Prager E, Zeyda M, Drbal K, Zlabinger GJ, Stulnig TM and Stockinger H

    Institute of Immunology, University of Vienna, Vienna, Austria.

    The plasma membrane is compartmentalized into microdomains and the association/dissociation of receptors and signaling molecules with/from these membrane domains is a major principle for regulation of signal transduction. By following the reorganization of microdomains on living cells and performing biochemical studies, we show that Ab targeting of the T cell activation-associated Ag CD147 prevents TCR stimulation-dependent reorganization and clustering of microdomains. Triggering CD147 induces a displacement of the GPI-anchored coreceptors CD48 and CD59 from microdomains in human T lymphocytes. This perturbation of microdomains is accompanied by a selective inhibition of TCR-mediated T cell proliferation. The CD147-inhibited cells secret normal levels of IL-2 but acquire reduced amounts of the IL-2 receptor alpha-chain CD25. These results indicate that negative regulating signals can modulate microdomains and suggest a general mechanism for inhibition of receptor signaling.

    Journal of immunology (Baltimore, Md. : 1950) 2003;171;4;1707-14

  • Basigin (CD147): a multifunctional transmembrane protein involved in reproduction, neural function, inflammation and tumor invasion.

    Muramatsu T and Miyauchi T

    Department of Biochemistry, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan. tmurama@med.nagoya-u.ac.jp

    Basigin (Bsg) is a transmembrane glycoprotein with two immunoglobulin-like domains, and forms a family with embigin and neuroplastin. In these proteins a conserved glutamic acid is present in the middle for the transmembrane domain. Bsg is also called CD147 and EMMPRIN, and the symbol for the human basigin gene is BSG. BSG is located in chromosome 19 band p13. 3. Knockout mice deficient in the Bsg gene are sterile and show various neurological abnormalities. Bsg-deficient embryos are also difficult to implant. Bsg has been found to participate in the cell-surface orientation of monocarboxylic acid transporters (MCTs) to the plasma membrane. Dysfunction of the retina in Bsg-deficient mice is ascribed to the failure of plasma membrane integration of MCTs in the tissue. Bsg is also involved in inflammatory processes and is proposed to be a receptor of cyclophilin A; it is also likely to participate in HIV infection. Bsg in tumor cells triggers the production or release of matrix metalloproteinases in the surrounding mesenchymal cells and tumor cells, thereby contributing to tumor invasion. Furthermore, the association of Bsg with integrins might be important in signaling through Bsg.

    Histology and histopathology 2003;18;3;981-7

  • Identification and quantification of N-linked glycoproteins using hydrazide chemistry, stable isotope labeling and mass spectrometry.

    Zhang H, Li XJ, Martin DB and Aebersold R

    Institute for Systems Biology, 1441 N 34th Street, Seattle, Washington 98103-8904, USA.

    Quantitative proteome profiling using stable isotope protein tagging and automated tandem mass spectrometry (MS/MS) is an emerging technology with great potential for the functional analysis of biological systems and for the detection of clinical diagnostic or prognostic marker proteins. Owing to the enormous complexity of proteomes, their comprehensive analysis is an as-yet-unresolved technical challenge. However, biologically or clinically important information can be obtained if specific, information-rich protein classes, or sub-proteomes, are isolated and analyzed. Glycosylation is the most common post-translational modification. Here we describe a method for the selective isolation, identification and quantification of peptides that contain N-linked carbohydrates. It is based on the conjugation of glycoproteins to a solid support using hydrazide chemistry, stable isotope labeling of glycopeptides and the specific release of formerly N-linked glycosylated peptides via peptide- N-glycosidase F (PNGase F). The recovered peptides are then identified and quantified by MS/MS. We applied the approach to the analysis of plasma membrane proteins and proteins contained in human blood serum.

    Funded by: NCI NIH HHS: K08CA97282-01, R33 CA93302

    Nature biotechnology 2003;21;6;660-6

  • Overexpression of extracellular matrix metalloproteinase inducer in multidrug resistant cancer cells.

    Yang JM, Xu Z, Wu H, Zhu H, Wu X and Hait WN

    Department of Pharmacology, The Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey/Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA.

    Multidrug resistant (MDR) cancer cells overexpressing P-glycoprotein (P-gp) display variations in invasive and metastatic behavior. We previously reported that these properties of MDR cancer cell lines overexpressing P-gp could be altered by chemotherapeutic drugs or MDR modulators (R. S. Kerbel et al., Cancer Surv., 7: 597-629, 1988). To attempt to clarify the mechanism(s) underlying these observations, we studied the expression of extracellular matrix metalloproteinase inducer (EMMPRIN), a glycoprotein enriched on the surface of tumor cells that can stimulate the production of matrix metalloproteinases (MMPs), in sensitive and MDR cancer cells. Using immunofluorescence staining and fluorescence-activated cell sorting analysis, we found that EMMPRIN expression was increased in MDR carcinoma cell lines, MCF-7/AdrR, KBV-1, and A2780Dx5, as compared to their parental counterparts. The MDR cell lines produced more matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-2 (MMP-2), and matrix metalloproteinase-9 (MMP-9), as determined by zymography, Western blot, and reverse transcription-PCR. Treatment of MDR cells with an anti-EMMPRIN antibody inhibited the activity of MMP-1, MMP-2, and MMP-9. In MDR cell line MCF-7/AdrR, an increased in vitro invasive ability was observed as compared with the sensitive line MCF-7, and EMMPRIN antibody could inhibit the in vitro invasion in drug-resistant cells. In addition, the expression and activity of MMP-1, MMP-2, and MMP-9 in MDR cells were decreased by treatment with U-0126, an inhibitor of mitogen-activated protein kinase/extracellular signal regulated kinase (MAPK/Erk). Our results suggest that during the development of MDR, the expression of EMMPRIN is responsible for the increased activity of MMP in MDR cell lines.

    Funded by: NCI NIH HHS: CA 66077, CA 72720

    Molecular cancer research : MCR 2003;1;6;420-7

  • The immunoglobulin-superfamily molecule basigin is a binding protein for oligomannosidic carbohydrates: an anti-idiotypic approach.

    Heller M, von der Ohe M, Kleene R, Mohajeri MH and Schachner M

    Department of Neurobiology, Swiss Federal Institute of Technology, Zürich, Switzerland.

    Recognition molecules that carry carbohydrate structures regulate cell interactions during development and play important roles in synaptic plasticity and regeneration in the adult. Glycans appear to be involved in these interactions. We have searched for binding proteins for oligomannosidic structures using the L3 antibody directed against high mannose-type glycans in an anti-idiotypic approach. A selected monoclonal anti-idiotype antibody was used for affinity chromatography and identified basigin as a binding protein from mouse brain detergent lysates. Basigin was found to bind to high mannose-carrying cell recognition molecules, such as myelin-associated glycoprotein, L1, the beta2-subunit of Na+/K+-ATPase and an oligomannosidic neoglycolipid. Furthermore, basigin was involved in outgrowth of astrocytic processes in vitro. A striking homology between the first immunoglobulin (Ig)-like domain of basigin and the fourth Ig-like domain of NCAM, previously shown to bind to oligomannosidic glycans, and the lectin domain of the mannose receptor confirms that basigin is an oligomannose binding lectin. To our knowledge this is the first report that anti-idiotypic antibodies can be used to identify binding partners for carbohydrates.

    Journal of neurochemistry 2003;84;3;557-65

  • Upregulation of extracellular matrix metalloproteinase inducer (EMMPRIN) and gelatinases in human atherosclerosis infected with Chlamydia pneumoniae: the potential role of Chlamydia pneumoniae infection in the progression of atherosclerosis.

    Choi EY, Kim D, Hong BK, Kwon HM, Song YG, Byun KH, Park HY, Whang KC and Kim HS

    Yonsei Cardiovascular Center, Cardiovascular Research Institute, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.

    Chlamydia pneumoniae infection implicated as an important etiologic factor of atherosclerosis, especially in coronary artery disease (CAD), was found in vitro to be associated with the induction of matrix metalloproteinases (MMPs). An extracellular matrix metalloproteinase inducer (EMMPRIN)/ membrane-type 1 matrix metalloproteinase (MT1-MMP) system which induces and activates MMPs, is suggested to be functional and were upregulated in the failing myocardium. However, the upstream regulation of MMPs by C. pneumoniae within atheroma itself remains unclear. We evaluated the seroepidemiologic study of C. pneumoniae infection in CAD patients (n= 391) and controls (n=97) and performed histopathological and in vitro analysis in atherosclerotic vascular tissues obtained from patients with seropositive to C. pneumoniae (n=20), by using immunochemistry for C. pneumoniae, EMMPRIN/MT1-MMP, MMP-2, and MMP-9. The seropositive rates of both anti-C. pneumoniae IgG and IgA were 56.7% in CAD group and 43.3% in control group (P=0.033). Seropositive rate was increased in subgroups of CAD patients without conventional coronary risk factors compared to those with conventional risk factors. Immunoreactivities of EMMPRIN, MT1-MMP, MMP-2, and MMP-9 were increased in the atheromatous plaque itself, predominantly in immunoreactive macrophages/mononuclear cells to C. pneumoniae. Furthermore, Western blot analysis showed that EMMPRIN and MMP-2 were detected more prominently in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. Zymographic analysis revealed that activities of MMP-2 and MMP-9 were more increased in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. The present study demonstrated upstream regulation of MMPs can be induced by C. pneumoniae within atheromatous plaque itself. These findings help to understand the potential role of C. pneumoniae in the progression of atherosclerosis.

    Experimental & molecular medicine 2002;34;6;391-400

  • Breast cancer cell-derived EMMPRIN stimulates fibroblast MMP2 release through a phospholipase A(2) and 5-lipoxygenase catalyzed pathway.

    Taylor PM, Woodfield RJ, Hodgkin MN, Pettitt TR, Martin A, Kerr DJ and Wakelam MJ

    Cancer Research UK Institute for Cancer Studies, Birmingham University, Birmingham, B15 2TT, UK.

    Metalloproteinases (MMP) produced by both cancer and normal stromal fibroblast cells play a critical role in the metastatic spread of tumours, however little is known of the regulation of their release. In this report we demonstrate that breast cancer cells in culture release apparently full length soluble EMMPRIN that promotes the release of pro-MMP2 from fibroblasts. The generation of MMP2 is mediated by activation of phospholipase A(2) and 5-lipoxygenase. These results suggest that the production of soluble EMMPRIN, phospholipase A(2) and 5-lipoxygenase activities are sites for potential therapeutic intervention.

    Oncogene 2002;21;37;5765-72

  • Extracellular matrix metalloproteinase inducer (EMMPRIN) is induced upon monocyte differentiation and is expressed in human atheroma.

    Major TC, Liang L, Lu X, Rosebury W and Bocan TM

    Cardiovascular Pharmacology, Pfizer Global Research & Development, Pfizer, Inc, Ann Arbor, Mich 48105, USA. terry.major@pfizer.com

    Objective: Because extracellular matrix metalloproteinase inducer (EMMPRIN), a tumor cell-derived protein, induces matrix metalloproteinases (MMPs) in fibroblasts and because MMPs are important in atheroma formation, we investigated if EMMPRIN was expressed in granulocyte/macrophage-colony stimulating factor (GM-CSF)-differentiated human peripheral blood monocytes (HPBM) and macrophage foam cells. In addition, EMMPRIN was studied for its expression in human atheroma.

    After 10 days of GM-CSF-induced monocyte differentiation, EMMPRIN mRNA increased 5- to 8-fold relative to undifferentiated monocytes. GM-CSF treatment of HPBM revealed that both EMMPRIN mRNA and protein were upregulated by day 2 over undifferentiated monocytes. GM-CSF-differentiated HPBM showed characteristic macrophage phenotype by showing increases in pancake-like morphology and increases in biochemical markers such as apolipoprotein E, MMP-9, and cholesterol ester (CE). While acetylated LDL treatment of the 10-day GM-CSF-differentiated HPBM increased CE mass 13- to 321-fold, EMMPRIN expression was unchanged relative to nonlipid-loaded macrophages. In human coronary atherosclerotic samples, EMMPRIN was observed in CD68(+) macrophage-rich areas as well as areas of MMP-9 expressions.

    Conclusions: Based on these data, we conclude that monocyte differentiation induces EMMPRIN expression, CE enrichment of foam cells has no further effect on EMMPRIN expression, and EMMPRIN is present in human atheroma. Therefore, EMMPRIN may play a role in atherosclerosis development.

    Arteriosclerosis, thrombosis, and vascular biology 2002;22;7;1200-7

  • EMMPRIN (CD 174) is expressed in Hodgkin's lymphoma and anaplastic large cell lymphoma. An immunohistochemical study of 60 cases.

    Thorns C, Feller AC and Merz H

    Institute of Pathology, Medical University of Luebeck, Germany. thorns@patho.mu-luebeck.de

    Background: Matrix metalloproteinases are involved in tumor invasion and metastatic spread. Expression of metalloproteinases is induced by the extracellular matrix metalloproteinase inducer (EMMPRIN). Their activity can be inhibited by several tissue inhibitors of metalloproteinases (TIMP1-to-4). Whereas TIMP-1 expression is described for high-grade malignant lymphomas and seems to be correlated with unfavourable prognosis, there are no data on the expression of EMMPRIN in malignant lymphoma.

    We investigated 60 cases of Hodgkin's lymphoma and anaplastic large cell lymphoma for TIMP-1 and EMMPRIN expression using immunohistochemistry.

    Results: EMMPRIN was expressed in all but four cases. EMMPRIN and TIMP-1 were co-expressed in two-thirds of the Hodgkin's lymphomas and anaplastic large cell lymphomas.

    Conclusion: This is the first report on the expression of EMMPRIN in malignant lymphoma. We speculate that EMMPRIN and TIMP-1 may be important in the pathogenesis of anaplastic large cell lymphoma and Hodgkin's disease.

    Anticancer research 2002;22;4;1983-6

  • Active site residues of cyclophilin A are crucial for its signaling activity via CD147.

    Yurchenko V, Zybarth G, O'Connor M, Dai WW, Franchin G, Hao T, Guo H, Hung HC, Toole B, Gallay P, Sherry B and Bukrinsky M

    Picower Institute for Medical Research, Manhasset, New York 11030, USA.

    Cyclophilin A (CyPA), a ubiquitously distributed intracellular protein, is a peptidylprolyl cis-trans-isomerase and the major target of the potent immunosuppressive drug cyclosporin A. Although expressed predominantly as an intracellular molecule, CyPA is secreted by cells in response to inflammatory stimuli and is a potent neutrophil and eosinophil chemoattractant in vitro and in vivo. The mechanisms underlying CyPA-mediated signaling and chemotaxis are unknown. Here, we identified CD147 as a cell surface receptor for CyPA and demonstrated that CD147 is an essential component in the CyPA-initiated signaling cascade that culminates in ERK activation. Both signaling and chemotactic activities of CyPA depended also on the presence of heparans, which served as primary binding sites for CyPA on target cells. The proline 180 and glycine 181 residues in the extracellular domain of CD147 were critical for signaling and chemotactic activities mediated by CD147. Also crucial were active site residues of CyPA, because rotamase-defective CyPA mutants failed to initiate signaling events. These results establish cyclophilins as natural ligands for CD147 and suggest an unusual, rotamase-dependent mechanism of signaling.

    Funded by: NIAID NIH HHS: R01 AI 29110, R01 AI 38245

    The Journal of biological chemistry 2002;277;25;22959-65

  • Basigin (CD147) is expressed on melanoma cells and induces tumor cell invasion by stimulating production of matrix metalloproteinases by fibroblasts.

    Kanekura T, Chen X and Kanzaki T

    Department of Dermatology, Kagoshima University Faculty of Medicine, 8-35-1 Sakuragaoka, Kagoshima 890-8530, Japan. takurok@m2.kufm.kagoshima-u.ac.jp

    EMMPRIN, which is identical to human basigin (CD147), interacts with fibroblasts and stimulates expression of MMPs, which play an important role in tumor invasiveness and metastasis. In the present study, we demonstrated that coculture of basigin-expressing human MM cells with dermal fibroblasts resulted in the induction of MMP-1, MMP-2, MMP-3 and MT1-MMP production by fibroblasts and of melanoma cell invasion through a reconstituted basement membrane. Antibody to basigin inhibited both the production of MMPs by fibroblasts and the invasiveness of melanoma cells. Expression of basigin and MMPs in MM and surrounding fibroblasts was examined immunohistochemically in 28 specimens from 18 MM patients without metastasis and 10 with metastasis, to investigate whether basigin plays a role in metastasis of MM in vivo. Basigin was expressed in melanoma cells but not in fibroblasts. MM with metastasis had significantly higher basigin expression compared to MM without metastasis. There were significant differences between MMs with and without metastasis in the expression of MMPs in both melanoma cells and fibroblasts. Expression of MMPs in fibroblasts was positively correlated with expression levels of basigin. These immunohistochemic findings indicate that MMPs might be expressed in fibroblasts as well as melanoma cells concomitantly with basigin, which was expressed in melanoma cells more frequently in MM with metastasis. Basigin is highly expressed in melanoma cells and may play an important role in their invasiveness and metastasis by stimulating surrounding fibroblasts to express MMPs.

    International journal of cancer. Journal international du cancer 2002;99;4;520-8

  • EMMPRIN-mediated MMP regulation in tumor and endothelial cells.

    Caudroy S, Polette M, Nawrocki-Raby B, Cao J, Toole BP, Zucker S and Birembaut P

    Inserm U514, IFR53, CHU Maison-Blanche, Reims, France.

    Tumor invasion and metastasis are multistep processes which require extracellular matrix remodeling by proteolytic enzymes such as matrix metalloproteinases (MMPs). The production of these enzymes is stimulated by many soluble or cell-bound factors. Among these factors, extracellular matrix metalloproteinase inducer (EMMPRIN) is known to increase in vitro stromal cell production of MMP-1, MMP-2 and MMP-3. In this study, we demonstrated that EMMPRIN-transfected MDA-MB-436 tumor cells displayed a more invasive capacity than vector-transfected cells in a modified Boyden chamber invasion assay. Using gelatin zymography and protein analyses, we showed that EMMPRIN-transfected cancer cells produced significantly more latent and active MMP-2 and MMP-3 than vector-transfected cancer cells. We found that EMMPRIN did not regulate MMP-1, MMP-9, membrane type-1 MMP (MT1-MMP) expression and had also no effect on the production of the specific tissue inhibitors of MMPs (TIMPs), TIMP-1 and TIMP-2. We also demonstrated that tumor-derived EMMPRIN stimulated MMP-1, -2, and -3 without modification of MMP-9, MT1-MMP, TIMP-1 and TIMP-2 production in human umbilical vein endothelial cells (HUVEC). These data provide support for the role of EMMPRIN in tumor invasion, metastasis, and neoangiogenesis by stimulating extracellular matrix remodeling around tumor cell clusters, stroma, and blood vessels.

    Funded by: NCI NIH HHS: R01-CA79866

    Clinical & experimental metastasis 2002;19;8;697-702

  • CD147 is a signaling receptor for cyclophilin B.

    Yurchenko V, O'Connor M, Dai WW, Guo H, Toole B, Sherry B and Bukrinsky M

    The Picower Institute for Medical Research, Manhasset, New York 11030, USA.

    Cyclophilins A and B (CyPA and CyPB) are cyclosporin A binding proteins that can be secreted in response to inflammatory stimuli. We recently identified CD147 as a cell-surface receptor for CyPA and demonstrated that CD147 is an essential component in the CyPA-initiated signaling cascade that culminates in ERK activation and chemotaxis. Here we demonstrate that CD147 also serves as a receptor for CyPB. CyPB induced Ca(2+) flux and chemotaxis of CD147-transfected, but not control, CHO cells, and the chemotactic response of primary human neutrophils to CyPB was blocked by antibodies to CD147. These results suggest that CD147 serves as a receptor for extracellular cyclophilins.

    Biochemical and biophysical research communications 2001;288;4;786-8

  • CD147 is tightly associated with lactate transporters MCT1 and MCT4 and facilitates their cell surface expression.

    Kirk P, Wilson MC, Heddle C, Brown MH, Barclay AN and Halestrap AP

    Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.

    CD147 is a broadly expressed plasma membrane glycoprotein containing two immunoglobulin-like domains and a single charge-containing transmembrane domain. Here we use co-immunoprecipitation and chemical cross-linking to demonstrate that CD147 specifically interacts with MCT1 and MCT4, two members of the proton-linked monocarboxylate (lactate) transporter family that play a fundamental role in metabolism, but not with MCT2. Studies with a CD2-CD147 chimera implicate the transmembrane and cytoplasmic domains of CD147 in this interaction. In heart cells, CD147 and MCT1 co-localize, concentrating at the t-tubular and intercalated disk regions. In mammalian cell lines, expression is uniform but cross-linking with anti-CD147 antibodies caused MCT1, MCT4 and CD147, but not GLUT1 or MCT2, to redistribute together into 'caps'. In MCT-transfected cells, expressed protein accumulated in a perinuclear compartment, whereas co-transfection with CD147 enabled expression of active MCT1 or MCT4, but not MCT2, in the plasma membrane. We conclude that CD147 facilitates proper expression of MCT1 and MCT4 at the cell surface, where they remain tightly bound to each other. This association may also be important in determining their activity and location.

    The EMBO journal 2000;19;15;3896-904

  • Homo-oligomer formation by basigin, an immunoglobulin superfamily member, via its N-terminal immunoglobulin domain.

    Yoshida S, Shibata M, Yamamoto S, Hagihara M, Asai N, Takahashi M, Mizutani S, Muramatsu T and Kadomatsu K

    Departments of Biochemistry, Obstetrics and Gynecology, and Pathology, Nagoya University School of Medicine, Japan.

    Basigin (Bsg) is a highly glycosylated transmembrane protein with two immunoglobulin (Ig)-like domains. A number of studies, including gene targeting, have demonstrated that Bsg plays pivotal roles in spermatogenesis, implantation, neural network formation and tumor progression. In the present study, to understand the mechanism of action of Bsg, we determined its expression status on the plasma membrane. Cotransfection of Bsg expression vectors with two different tags clarified that Bsg forms homo-oligomers in a cis-dependent manner on the plasma membrane. If the disulfide bond of the more N-terminally located Ig-like domain was destroyed by mutations, Bsg could not form oligomers. In contrast, the mutations of the C-terminal Ig-like domain or N-glycosylation sites did not affect the association. The association of mouse and human Bsgs, which exhibit high homology in the transmembrane and intracellular domains but low homology in the extracellular domain, was very weak as compared with that within the same species, suggesting the importance of the extracellular domain in the association. If the extracellular domain of the human Ret protein was replaced with the N-terminal Ig-like domain of Bsg, the resulting chimera protein was associated with intact wild-type Bsg, but not if the C-terminal Ig-like domain, instead of the N-terminal one, of Bsg was used. No oligomer formation took place between the intact wild-type Ret and Bsg proteins. In conclusion, these data indicate that the N-terminal Ig-like domain is necessary and sufficient for oligomer formation by Bsg on the plasma membrane.

    European journal of biochemistry / FEBS 2000;267;14;4372-80

  • EMMPRIN (CD147), an inducer of matrix metalloproteinase synthesis, also binds interstitial collagenase to the tumor cell surface.

    Guo H, Li R, Zucker S and Toole BP

    Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.

    Extracellular matrix metalloproteinase inducer (EMMPRIN), also known as basigin or CD147, is a glycoprotein that is enriched on the surface of tumor cells and stimulates production of several matrix metalloproteinases by adjacent stromal cells. In this study, we have found that EMMPRIN not only stimulates the production of interstitial collagenase (MMP-1) but also forms a complex with MMP-1 at the tumor cell surface. Complex formation was demonstrated by phage display, affinity chromatography, and immunocytochemistry. Presentation of MMP-1 complexed to EMMPRIN at the tumor cell surface may be important in modifying the tumor cell pericellular matrix to promote invasion.

    Cancer research 2000;60;4;888-91

  • Characterization of the gene for human EMMPRIN, a tumor cell surface inducer of matrix metalloproteinases.

    Guo H, Majmudar G, Jensen TC, Biswas C, Toole BP and Gordon MK

    Department of Anatomy and Cellular Biology, Tufts Medical School, Boston, Massachusetts, USA.

    EMMPRIN (extracellular matrix metalloproteinase inducer) also known as CD147 and basigin, is a member of the immunoglobulin family that is present on the surface of tumor cells and stimulates nearby fibroblasts to synthesize matrix metalloproteinases. Using our EMMPRIN cDNA, we have isolated a cosmid clone that contains the human EMMPRIN gene. S1 analysis with a fragment of the gene clone and primer extension of the mRNA was performed to determine the transcription start site. PCR and sequence analysis have defined the exon/intron organization of the gene and show that it is highly conserved with the mouse EMMPRIN/basigin gene. About 950 bases of the 5'-flanking region were examined for transcription factor consensus binding sites, locating three SP1 sites and two AP2 sites. The transcription start site was found to be located in a CpG island. Elements in the proximal promoter region were conserved in the human and mouse genes.

    Funded by: NCI NIH HHS: CA38817; NEI NIH HHS: EY09056

    Gene 1998;220;1-2;99-108

  • Generation of monoclonal antibodies to integrin-associated proteins. Evidence that alpha3beta1 complexes with EMMPRIN/basigin/OX47/M6.

    Berditchevski F, Chang S, Bodorova J and Hemler ME

    Dana Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.

    The alpha3beta1 integrin forms complexes with other cell-surface proteins, including transmembrane-4 superfamily (TM4SF) proteins (e. g. CD9, CD53, CD63, CD81, and CD82). To identify additional cell-surface proteins associated with alpha3beta1 integrin, a monoclonal antibody selection protocol was developed. Mice were immunized with integrin alpha3beta1-containing complexes isolated from HT1080 fibrosarcoma cells, and then 712 hybridoma clones were produced, and 95 secreted antibodies that recognized the HT1080 cell surface. Among these, 12 antibodies directly recognizing integrin alpha3 or beta1 subunits were eliminated. Of the remaining 83, 16 co-immunoprecipitated proteins that resembled integrins under non-stringent detergent conditions. These 16 included 15 monoclonal antibodies recognizing EMMPRIN/basigin/OX-47/M6, a 45-55-kDa transmembrane protein with two immunoglobulin domains. The EMMPRIN protein associated with alpha3beta1 and alpha6beta1, but not alpha2beta1 or alpha5beta1, as shown by reciprocal immunoprecipitation experiments. Also, association with alpha3beta1 was confirmed by cell-surface cross-linking and immunofluorescence co-localization experiments. Importantly, EMMPRIN-alpha3beta1 complexes appear not to contain TM4SF proteins, suggesting that they are distinct from TM4SF protein-alpha3beta1 complexes.

    Funded by: NCI NIH HHS: CA42368

    The Journal of biological chemistry 1997;272;46;29174-80

  • The Oka blood group antigen is a marker for the M6 leukocyte activation antigen, the human homolog of OX-47 antigen, basigin and neurothelin, an immunoglobulin superfamily molecule that is widely expressed in human cells and tissues.

    Spring FA, Holmes CH, Simpson KL, Mawby WJ, Mattes MJ, Okubo Y and Parsons SF

    Bristol Institute for Transfusion Sciences, GB. fran.spring@msmail.nbs.nhs.uk

    The high-frequency blood group antigen Ok(a) is carried on a red cell membrane glycoprotein (gp) of 35-69 kDa that is widely distributed on malignant cells of different origins. Immunostaining of hemopoietic cells and a range of normal human tissues demonstrated a wide distribution of the Ok(a) gp that appears to be nonlineage-restricted, although certain tissues show differentiation-related expression. Ok(a) gp was purified from red cell membranes by immunoaffinity chromatography using mAb A103 and amino acid sequence analysis was performed. The N-terminal 30 amino acids are identical to the predicted sequence of M6 leukocyte activation antigen (M6), a member of the Ig superfamily (IgSF) with two IgSF domains. There are homologs in rat (MRC OX-47 or CE9), in mouse (basigin or gp42), and in chicken (HT7 or neurothelin). The molecular basis of the Ok(a) mutation was established by sequencing M6 cDNA derived from normal and Ok(a-) EBV-transformed B cell lines. A point mutation in the translated portion of M6 cDNA, G331AG-->AAG gives rise to a predicted E92-->K amino acid change in the first Ig-like domain of the Ok(a-) form of the protein. Transfection of mouse NS-0 cells with normal or Ok(a-) cDNA confirmed the identity of the protein and only the Ok(a-) transfectants failed to react with monoclonal anti-Ok(a) Ab.

    European journal of immunology 1997;27;4;891-7

  • Human keratinocytes express EMMPRIN, an extracellular matrix metalloproteinase inducer.

    DeCastro R, Zhang Y, Guo H, Kataoka H, Gordon MK, Toole Bp and Biswas G

    Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts, USA.

    Increased levels of matrix metalloproteinases are associated with tissue degradation and remodeling during tumor invasion and wound healing. In both processes, there is evidence that cell interactions between fibroblasts and tumor cells or keratinocytes lead to increases in metalloproteinase production. We have previously isolated and purified a tumor cell surface protein, EMMPRIN (extracellular matrix metalloproteinase inducer), which stimulates production of interstitial collagenase, gelatinase A, and stromelysin-1 by fibroblasts, and we have obtained cDNA clones that encode the EMMPRIN protein from LX-1 human lung carcinoma cells. In this study we report immunolocalization of EMMPRIN around the surface of human keratinocytes in vitro and in vivo, and isolation of cDNAs that encode the entire open reading frame for EMMPRIN from a human keratinocyte library. Comparison of the EMMPRIN cDNAs from normal human keratinocytes and LX-1 human tumor cells by nucleotide sequence analysis, expression of the recombinant proteins, and in vitro translation using the cDNAs from the two sources indicate that they express very similar forms of EMMPRIN. Native EMMPRIN isolated directly from extracts of keratinocytes, however, is slightly smaller in size and is present at a lower concentration compared with that from LX-1 tumor cells. These results establish the presence of EMMPRIN in the normal epidermis and raise the possibility of its involvement in regulation of matrix remodeling at the epidermal-dermal interface.

    Funded by: NCI NIH HHS: CA 38817

    The Journal of investigative dermatology 1996;106;6;1260-5

  • The human tumor cell-derived collagenase stimulatory factor (renamed EMMPRIN) is a member of the immunoglobulin superfamily.

    Biswas C, Zhang Y, DeCastro R, Guo H, Nakamura T, Kataoka H and Nabeshima K

    Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts 02111.

    Tumor cell-derived collagenase stimulatory factor, renamed extracellular matrix metalloproteinase inducer (EMMPRIN), is a M(r) approximately 58,000 glycoprotein which is located on the outer surface of human tumor cells and which interacts with fibroblasts to stimulate expression of several matrix metalloproteinases in the fibroblasts. In this study, we have used several approaches to isolate a complementary DNA encoding EMMPRIN. Several peptide sequences obtained from the isolated M(r) 58,000 glycoprotein are found in the translated complementary DNA clone, verifying its identity. Computer database searches indicate that EMMPRIN is a member of the immunoglobulin superfamily and that the deduced amino acid sequence of EMMPRIN is identical to that recently reported for human basigin and M6 antigen, molecules of previously undetermined biological function.

    Funded by: NCI NIH HHS: CA 38817

    Cancer research 1995;55;2;434-9

  • Mapping basigin (BSG), a member of the immunoglobulin superfamily, to 19p13.3.

    Kaname T, Miyauchi T, Kuwano A, Matsuda Y, Muramatsu T and Kajii T

    Department of Biochemistry, Faculty of Medicine, Kagoshima University, Japan.

    Basigin is a novel member of the immunoglobulin superfamily ubiquitously expressed in various tissues. We mapped the basigin gene at 19p13.3, using a 1.6-kb cDNA fragment of the gene as a probe and sequential fluorescence in situ hybridization and G-banding on human metaphase chromosomes.

    Cytogenetics and cell genetics 1993;64;3-4;195-7

  • Human leukocyte activation antigen M6, a member of the Ig superfamily, is the species homologue of rat OX-47, mouse basigin, and chicken HT7 molecule.

    Kasinrerk W, Fiebiger E, Stefanová I, Baumruker T, Knapp W and Stockinger H

    Institute of Immunology-Vienna International Research Cooperation Center, Sandoz Forschungsinstitut, Austria.

    Peripheral granulocytes from rheumatoid arthritis and reactive arthritis patients were recently found to express higher levels of a newly defined Ag, termed M6, in comparison to granulocytes from healthy subjects. We present here the molecular characterization of M6 Ag and show that it is a novel human leukocyte activation-associated cell surface glycoprotein. Peripheral lymphocytes do not significantly express M6 Ag, however, it appears upon 3-day PHA-activated T blasts. On monocytes, which constitutively express M6 Ag, it is down-regulated on day 1 but re-induced on day 3 of granulocyte-macrophage CSF stimulation. SDS-PAGE analysis of M6 immunoprecipitates shows a single band of 54 kDa under nonreducing conditions that shifts to 65 kDa under reducing conditions. Endoglycosidase F treatment of M6 immunoprecipitate reveals that 50% of the M6 molecule is composed of N-linked carbohydrates. By modifying the COS cell cloning strategy, we have isolated cDNA clones encoding M6 Ag. M6 cDNA hybridizes with a single mRNA transcript of approximately 1.7 kb in Northern blotting. Comparison analysis of the M6 sequence indicates that M6 Ag is a member of the Ig superfamily and the species homologue of rat OX-47 Ag, mouse basigin (gp42), and chicken HT7 molecule. The highly conserved remarkable transmembrane domain suggests that the M6 Ag may be a component of a multichain complex in the plasma membrane.

    Journal of immunology (Baltimore, Md. : 1950) 1992;149;3;847-54

  • The basigin group of the immunoglobulin superfamily: complete conservation of a segment in and around transmembrane domains of human and mouse basigin and chicken HT7 antigen.

    Miyauchi T, Masuzawa Y and Muramatsu T

    Japan Immunoresearch Laboratories, Gunma.

    Basigin belongs to the immunoglobulin superfamily and may be related to the primordial form of the superfamily. Human basigin cDNA was isolated and sequenced, and the predicted protein structure was compared with that of mouse basigin and two related molecules, embigin and the chicken blood-brain barrier antigen HT7. Between human and mouse basigin, 58% of the amino acids were identical and 80% of the changes were conservative. A stretch of 29 amino acid residues in the transmembrane and cytoplasmic domains was conserved not only in human and mouse basigin but also in HT7 antigen. The conserved structure may be required for interaction with a membranous protein. In addition, the relationship of basigin with other members of the immunoglobulin superfamily has been evaluated.

    Journal of biochemistry 1991;110;5;770-4

  • Partial sequencing and characterization of the tumor cell-derived collagenase stimulatory factor.

    Nabeshima K, Lane WS and Biswas C

    Department of Anatomy and Cellular Biology, Tufts University Health Science Schools, Boston, Massachusetts 02111.

    A tumor cell-derived, collagenase stimulatory factor (TCSF), previously isolated and purified from LX-1 human lung carcinoma cells and judged by immunoblotting and SDS-PAGE to contain a single protein of approximately 58 kDa, has been further analyzed for its biological activity and composition. Three significant new findings have been made. First, the biological activity of TCSF preparations was shown definitively to reside in the 58-kDa protein. This was achieved in two ways: (a) a polyclonal antibody was raised against the 58-kDa protein, after excision from an SDS-PAGE gel, and shown to inhibit the stimulation of fibroblast collagenase production by TCSF preparations; (b) the 58-kDa protein was eluted from a transblot of purified TCSF and shown to stimulate fibroblast collagenase production. Second, partial sequencing of the 58-kDa protein revealed no significant homologies with other known collagenase stimulatory factors. Third, purified TCSF was found, on transblotting to Immobilon, to contain a doublet of 58 kDa (TCSF1) and 54 kDa (TCSF2) proteins; the former was present in higher concentration than the latter. N-terminal amino acid sequencing of the two intact proteins and of four corresponding pairs of tryptic peptides derived from the two proteins showed identity in each case, indicating that TCSF1 and TCSF2 are very similar in composition. However, TCSF1 but not TCSF2 stimulated fibroblast collagenase production, confirming that the 58-kDa protein is the major active component of TCSF preparations.

    Funded by: NCI NIH HHS: CA 38817

    Archives of biochemistry and biophysics 1991;285;1;90-6

  • Basigin, a new member of the immunoglobulin superfamily: genes in different mammalian species, glycosylation changes in the molecule from adult organs and possible variation in the N-terminal sequences.

    Kanekura T, Miyauchi T, Tashiro M and Muramatsu T

    Department of Dermatology, Faculty of Medicine, Kagoshima University, Japan.

    Basigin is a new member of the immunoglobulin superfamily with homology to both the immunoglobulin V domain and major histocompatibility complex class II antigen beta-chain. Southern blot analysis indicated that the basigin gene was present as a single copy or as a few copies per mouse genome. Although a homologous gene was detected in the hamster and human, Southern and Northern blotting experiments indicated considerable species specificity in the basigin structure. The molecular weight of N-glycanase-treated basigin from embryonal carcinoma cells was about 32,000 and was close to the value of basigin polypeptide inferred from the cDNA sequence; the result confirmed the open reading frame of basigin. Upon Western blotting, large amounts of basigin were detected in the mouse kidney as a glycoprotein bound to Ricinus communis agglutinin (RCA)-I and as a glycoprotein bound to concanavalin A; the molecular weight of the former was 38,000-43,000, and of the latter was 30,000. Basigin of the molecular weight of 48,000 was detected in RCA-I-binding glycoproteins of the liver, small intestine and spleen. Thus, different forms of basigin can be produced by different modes of glycosylation. Another source of heterogeneity of basigin may be differences in N-terminal sequences, since cDNA clones with different 5' coding sequences were identified.

    Cell structure and function 1991;16;1;23-30

  • The glucose-lactic acid cycle and gluconeogenesis.

    Cori CF

    Current topics in cellular regulation 1981;18;377-87

Gene lists (4)

Gene List Source Species Name Description Gene count
L00000009 G2C Homo sapiens Human PSD Human orthologues of mouse PSD adapted from Collins et al (2006) 1080
L00000016 G2C Homo sapiens Human PSP Human orthologues of mouse PSP adapted from Collins et al (2006) 1121
L00000069 G2C Homo sapiens BAYES-COLLINS-HUMAN-PSD-FULL Human cortex biopsy PSD full list 1461
L00000071 G2C Homo sapiens BAYES-COLLINS-MOUSE-PSD-FULL Mouse cortex PSD full list (ortho) 1556
© G2C 2014. The Genes to Cognition Programme received funding from The Wellcome Trust and the EU FP7 Framework Programmes:
EUROSPIN (FP7-HEALTH-241498), SynSys (FP7-HEALTH-242167) and GENCODYS (FP7-HEALTH-241995).

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