G2Cdb::Gene report

Gene id
G00002011
Gene symbol
MYH11 (HGNC)
Species
Homo sapiens
Description
myosin, heavy chain 11, smooth muscle
Orthologue
G00000762 (Mus musculus)

Databases (9)

Curated Gene
OTTHUMG00000073427 (Vega human gene)
Gene
ENSG00000133392 (Ensembl human gene)
4629 (Entrez Gene)
168 (G2Cdb plasticity & disease)
MYH11 (GeneCards)
Literature
160745 (OMIM)
Marker Symbol
HGNC:7569 (HGNC)
Protein Expression
2302 (human protein atlas)
Protein Sequence
P35749 (UniProt)

Synonyms (2)

  • SMHC
  • SMMHC

Diseases (9)

Disease Nervous effect Mutations Found Literature Mutations Type Genetic association?
D00000093: Acute myeloid leukaemia N Y (15041229) Translocation fusion (with another gene) (TF) N
D00000093: Acute myeloid leukaemia N Y (15075086) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (15167911) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (15223639) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (15224374) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (15269306) Translocation fusion (with another gene) (TF) Y
D00000090: Precursor-B-cell acute lymphoblastic leukaemia N Y (15339697) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (15339697) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (15820957) Deletion (D) Y
D00000103: Leukaemia N Y (15968309) Translocation fusion (with another gene) (TF) Y
D00000118: Therapy-related myelodysplastic syndrome N Y (16165210) Translocation fusion (with another gene) (TF) Y
D00000095: Chronic myelogenous leukaemia N Y (16203287) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (16281071) Translocation fusion (with another gene) (TF) Y
D00000095: Chronic myelogenous leukaemia N Y (16393682) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (16393682) Translocation fusion (with another gene) (TF) Y
D00000239: Ascending thoracic aortic aneurysms leading to type A dissections N Y (16444274) Splice site mutation (SpS) Y
D00000239: Ascending thoracic aortic aneurysms leading to type A dissections N Y (16444274) Microinsertion (MI) Y
D00000287: Patent ductus arteriosus N Y (16444274) Splice site mutation (SpS) Y
D00000287: Patent ductus arteriosus N Y (16444274) Microinsertion (MI) Y
D00000093: Acute myeloid leukaemia N Y (16504290) Translocation fusion (with another gene) (TF) Y
D00000097: Granulocytic sarcoma of mesentery N Y (16504290) Translocation fusion (with another gene) (TF) Y
D00000288: Infantile hypertrophic pyloric stenosis N Y (16826529) No mutation found (N) N
D00000093: Acute myeloid leukaemia N Y (17052753) Translocation fusion (with another gene) (TF) Y
D00000093: Acute myeloid leukaemia N Y (17287858) Translocation fusion (with another gene) (TF) Y

References

  • Detection of the CBFB/MYH11 fusion gene in de novo acute myeloid leukemia (AML): a single-institution study of 224 Japanese AML patients.

    Monma F, Nishii K, Shiga J, Sugahara H, Lorenzo F, Watanabe Y, Kawakami K, Hosokai N, Yamamori S, Katayama N and Shiku H

    Division of Hematology and Oncology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.

    The cytogenetic findings in acute myeloid leukemia (AML) are a powerful prognostic indicator. Among these abnormalities, the World Health Organization has classified inv(16)(p13q22), which is closely associated with the M4E classification in the French-American-British system, as indicating a good-risk AML. However, this chromosomal abnormality can often be difficult to detect. In this study, we used RT-PCR and FISH analysis to examine 224 Japanese adult de novo AML patients for the presence of the CBFB/MYH11 fusion transcript at the time of diagnosis. The CBFB/MYH11 fusion gene was detected in 17 patients (7.6%): eight patients had the inv(16) chromosome and in all of them it was M4E; nine patients did not have abnormalities in chromosome 16. AML with the CBFB/MYH11 fusion gene but without inv(16) was found in M2, M4, and M5, but not in M4E patients. There were no statistically significant differences in the clinical features of patients with the inv(16) and those with the cryptic inv(16) chromosome. These results indicate that even if eosinophilia is not found, molecular screening for CBFB/MYH11 fusion gene should be performed in all AML patients at the time of diagnosis to help guide disease management.

    Leukemia research 2007;31;4;471-6

  • Rare CBFB-MYH11 fusion transcripts in AML with inv(16)/t(16;16) are associated with therapy-related AML M4eo, atypical cytomorphology, atypical immunophenotype, atypical additional chromosomal rearrangements and low white blood cell count: a study on 162 patients.

    Schnittger S, Bacher U, Haferlach C, Kern W and Haferlach T

    MLL Munich Leukemia Laboratory, Munich, Germany. susanne.schnittger@mll-online.com

    The spectrum of CBFB-MYH11 fusion transcripts in acute myeloid leukemia (AML) M4eo with inv(16)/t(16;16) is heterogeneous. Approximately 85% show type A CBFB-MYH11 fusion transcripts. In addition, more than 10 different fusion transcripts have been reported. The prognostic impact and biological background of rare fusion transcripts remain open. In this study, a molecular characterization of CBFB-MYH11 transcripts in 162 patients with CBFB-MYH11 positive AML at diagnosis was performed. In total, 128 patients (79.0%) showed the fusion transcript type A, whereas nine different rare CBFB-MYH11 fusion genes were detected in 34 cases (21.0%). Rare fusion transcripts were found more frequently in therapy-related AML (P=0.0106). Numerical gains of the chromosomes 8, 21 and 22 were more frequently associated with type A (28.3%) than with rare fusions (12.9%) (P=0.012). Median white blood cell (WBC) count was higher in type A (35.4 G/l; range=1.1-279 G/l) than in cases with rare types (7.8 G/l; range=0.8-148.0 G/l) (P<0.0001). Rare fusion transcripts were correlated with an atypical cytomorphology not primarily suggestive for the FAB subtype M4eo (P=0.0203). Immunophenotype revealed lower CD2, CD13, CD33 and CD90 levels than in type A fusion cases (P=0.036, 0.002, 0.029 and 0.045, respectively). However, the type of fusion was not an independent prognostic parameter.

    Leukemia 2007;21;4;725-31

  • Granulocytic sarcoma of mesentery in acute myeloid leukemia with CBFB/MYH11 fusion gene but not inv(16) chromosome: case report and review of literature.

    Fujieda A, Nishii K, Tamaru T, Otsuki S, Kobayashi K, Monma F, Ohishi K, Nakase K, Katayama N and Shiku H

    Division of Hematology and Oncology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.

    Granulocytic sarcoma (GS) is a rare extra-medullary tumor and usually involves the skin, soft tissue, and lymph nodes. GS is found in 8% of acute myeloid leukemia (AML) patients, especially patients with t(8;21)AML. It has been suggested that GS is a poor prognostic factor in t(8;21)AML. Compared to t(8;21)AML, GS is rare in cases of inv(16)AML. Thus, the characteristics of inv(16) with GS are not well understood. Here, we describe a patient with AML and mesentery GS. The chromosomal analysis was normal, but molecular analysis detected the CBFB/MYH11 fusion gene in the blasts. A complete remission was achieved with standard induction therapy followed by high-dose cytarabine consolidation. We have also summarized 12 reported cases of inv(16)AML with GS and found that GS was commonly found in abdominal lesions. These observations suggest that when abdominal GS is diagnosed, an analysis of the CBFB/MYH11 fusion gene is necessary to make an appropriate decision regarding treatment options, even if no chromosomal abnormalities are found.

    Leukemia research 2006;30;8;1053-7

  • Linkage of monogenic infantile hypertrophic pyloric stenosis to chromosome 16p12-p13 and evidence for genetic heterogeneity.

    Capon F, Reece A, Ravindrarajah R and Chung E

    Department of Paediatrics and Child Health, The Rayne Building, University College London, WC1E 6JJ London, UK.

    Infantile hypertrophic pyloric stenosis (IHPS) is the most common form of bowel obstruction in infancy. The disease affects males four times more often than females and is considered a paradigm for the sex-modified model of multifactorial inheritance. However, pedigrees consistent with autosomal dominant inheritance have also been documented. We analyzed a 3-generation family with IHPS including 10 affected individuals (5 males and 5 females) and mapped the underlying disease locus to chromosome 16p12-p13 (LOD score 3.23) by using a single-nucleotide polymorphism-based genomewide scan. The analysis of 10 additional multiplex pedigrees yielded negative or nonsignificant LOD scores, indicating the presence of locus heterogeneity. Sequence analysis of candidate genes from the chromosome 16 disease interval excluded the presence of pathogenic mutations in the GRIN2A and MYH11 genes.

    American journal of human genetics 2006;79;2;378-82

  • Mutations in myosin heavy chain 11 cause a syndrome associating thoracic aortic aneurysm/aortic dissection and patent ductus arteriosus.

    Zhu L, Vranckx R, Khau Van Kien P, Lalande A, Boisset N, Mathieu F, Wegman M, Glancy L, Gasc JM, Brunotte F, Bruneval P, Wolf JE, Michel JB and Jeunemaitre X

    Assistance Publique Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Département de Génétique, 75015 Paris, France.

    We have recently described two kindreds presenting thoracic aortic aneurysm and/or aortic dissection (TAAD) and patent ductus arteriosus (PDA) and mapped the disease locus to 16p12.2-p13.13 (ref. 3). We now demonstrate that the disease is caused by mutations in the MYH11 gene affecting the C-terminal coiled-coil region of the smooth muscle myosin heavy chain, a specific contractile protein of smooth muscle cells (SMC). All individuals bearing the heterozygous mutations, even if asymptomatic, showed marked aortic stiffness. Examination of pathological aortas showed large areas of medial degeneration with very low SMC content. Abnormal immunological recognition of SM-MHC and the colocalization of wild-type and mutant rod proteins in SMC, in conjunction with differences in their coimmunoprecipitation capacities, strongly suggest a dominant-negative effect. Human MYH11 gene mutations provide the first example of a direct change in a specific SMC protein leading to an inherited arterial disease.

    Nature genetics 2006;38;3;343-9

  • Therapy-related myelodysplastic syndrome with inv(16)(p13q22) and I type CBFbeta/MYH11 after autologous transplantation: undetectable fusion transcript in pretransplant progenitor cells.

    Yamamoto K, Nishikawa S, Minagawa K, Yakushijin K, Okamura A and Matsui T

    Hematology/Oncology, Department of Medicine, Kobe University Graduate School of Medicine, Chuo-ku, Kobe 650-0017, Japan.

    We describe here a unique case of therapy-related myelodysplastic syndrome (t-MDS) with inv(16)(p13q22) after autologous stem cell transplantation for lymphoma. The rare and smallest I type CBFbeta/MYH11 fusion transcript with a breakpoint at nucleotide 399 of CBFbeta and at nucleotide 2134 of MYH11 was detected in the bone marrow cells by reverse transcription polymerase chain reaction analysis. However, the fusion transcript was undetectable in the pretransplant peripheral blood stem cells. These results suggest that the stem cell damage leading to t-MDS may be induced mainly by the conditioning regimen for transplantation. Taken together with previous reports, the I type fusion transcript is preferentially induced with chemotherapy.

    Leukemia research 2006;30;3;354-61

  • Coexistence of inversion 16 and the Philadelphia chromosome in acute and chronic myeloid leukemias : report of six cases and review of literature.

    Wu Y, Slovak ML, Snyder DS and Arber DA

    Division of Pathology, City of Hope National Medical Center, Duarte, CA, USA.

    We report 5 cases of chronic myelogenous leukemia (CML) and 1 case of acute myeloid leukemia (AML) with the dual presence of t(9;22) and inv(16). The 6 patients were 5 men and 1 woman with a median age of 42.5 years. All cases were BCR-ABL+ with p210 products detected in all CML cases and a p190 product detected in the AML case. An increase in bone marrow eosinophils was detected in 3 of 5 cases, and abnormal eosinophils were identified in these 3 cases. The CBFbeta-MYH11 fusion gene was confirmed in all 3 CML cases and the 1 AML case tested, and this correlated with the presence of abnormal eosinophils with coarse basophilic granules. Of 5 patients with CML, 4 had a rapid transformation to myeloid accelerated phase of blast crisis. The coexistence of t(9;22) and inv(16) in CML seems to correlate with more rapid transformation.

    American journal of clinical pathology 2006;125;2;260-6

  • Prognostic value of minimal residual disease (MRD) in acute myeloid leukemia (AML) with favorable cytogenetics [t(8;21) and inv(16)].

    Perea G, Lasa A, Aventín A, Domingo A, Villamor N, Queipo de Llano MP, Llorente A, Juncà J, Palacios C, Fernández C, Gallart M, Font L, Tormo M, Florensa L, Bargay J, Martí JM, Vivancos P, Torres P, Berlanga JJ, Badell I, Brunet S, Sierra J, Nomdedéu JF and Grupo Cooperativo para el Estudio y Tratamiento de las Leucemias Agudas y Miel

    Hematology Department, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain.

    Most patients with acute myeloid leukemia (AML) and t(8;21) or inv(16) have a good prognosis with current anthracycline- and cytarabine-based protocols. Tandem analysis with flow cytometry (FC) and real-time RT-PCR (RQ-PCR) was applied to 55 patients, 28 harboring a t(8;21) and 27 an inv(16), including one case with a novel CBFbeta/MYH11 transcript. A total of 31% (n=17) of CR patients relapsed: seven with t(8;21) and 10 with inv(16). The mean amount of minimal residual disease (MRD) detected by FC in relapsed and nonrelapsed patients was markedly different: 0.3 vs 0.08% (P=0.002) at the end of treatment. The mean number of fusion transcript copies/ ABL x 10(4) also differed between relapsed and non-relapsed patients: 2385 vs 122 (P=0.001) after induction, 56 vs 7.6 after intensification (P=0.0001) and 75 vs 3.3 (P=0.0001) at the end of chemotherapy. Relapses were more common in patients with FC MRD level >0.1% at the end of treatment than in patients with < or = 0.1%: cumulative incidence of relapse (CIR) was 67 and 21% (P=0.03), respectively. Likewise, using RQ-PCR, a cutoff level of >10 copies at the end of treatment correlated with a high risk of relapse: CIR was 75% for patients with RQ-PCR >10 compared to 21% for patients with RQ-PCR levels < or = 10 (P=0.04). Combined use of FC and RQ-PCR may improve MRD detection, and provide useful clinical information on relapse kinetics in AML patients.

    Leukemia 2006;20;1;87-94

  • inv(16)(p13q22) in chronic myelogenous leukemia in blast phase: a clinicopathologic, cytogenetic, and molecular study of five cases.

    Merzianu M, Medeiros LJ, Cortes J, Yin C, Lin P, Jones D, Glassman A, Kantarjian H and Huh Y

    Department of Hematopathology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.

    Blast phase (BP) in chronic myelogenous leukemia (CML) frequently is accompanied by cytogenetic abnormalities in addition to t(9;22)(q34;q11.2). We describe 5 patients with CML in blast phase (CML-BP) in which t(9;22) and inv(16)(p13q22) were identified by conventional cytogenetics, with confirmation of BCR-ABL and CBFss-MYH11 by fluorescence in situ hybridization. The morphologic findings at the time of BP resembled de novo acute myeloid leukemia (AML) carrying inv(16)(p13q22), with abnormal eosinophils in the bone marrow and monocytosis in the peripheral blood in all cases. In 1 patient, inv(16)(p13q22) and abnormal eosinophils were detected in the bone marrow 2 months before CML-BP. The clinical course of these patients was similar to patients with CML-BP without evidence of inv(16)(p13q22). These cases illustrate that inv(16)(p13q22) is a form of cytogenetic evolution that rarely occurs in patients with CML at the time of BP. In this setting, unlike de novo AML, inv(16)(p13q22) in CML-BP is not associated with a favorable prognosis.

    American journal of clinical pathology 2005;124;5;807-14

  • [Role of molecular screening for common fusion genes in the diagnosis and classification of leukemia].

    Zhu YL, Zhang Y, Zhu P, Yang Y, Du JW and Liu J

    Department of Haematology, Peking University First Hospital, Beijing 100034, China.

    Objective: To assess the value of common fusion genes analysis in the diagnosis and classification of leukemia by multiplex RT-PCR.

    Methods: The multiplex RT-PCR, including 8 parallel PCR reactions, could screen 86 mRNA breakpoints or splice variants at the same time, which was important for the diagnosis and prognosis of leukemia. Bone marrow samples from 161 cases of leukemia and 8 cases of myelodysplastic syndrome (MDS) were involved in the study. The distribution of common fusion genes in leukemia was analyzed by the method mentioned above in combination with clinical and morphological features.

    Results: Ten fusion genes were detected in 115 cases of leukemia, including AML1/ETO, PML/RAR alpha, PLZF/RAR alpha, dupMLL, MLL/AF6, MLL/AF10, CBFbeta/MYH11, BCR/ABL, Hox11, and EVI1 BCR/ABL was positive in all the 52 cases of chronic myeloid leukemia; PML/RAR alpha was found in 21 of 25 acute promyelocytic leukemia (APL), and PLZF/RAR alpha was detected in one case of APL. Sixteen cases of 17 AML1/ETO-positive acute leukemia (AL) belonged to FAB-M2 subtype, and one case was mixed leukemia. Three of 4 AL cases carrying CBFbeta/MYH11 were M4 subtype, and one was M5 subtype. MLL aberrations were found in 16 AL, in which all MLL/AF6 translocation existed in M5 subtype with classic monoblastic characters. Furthermore, BCR/ABL was detected in 5 acute lymphoblastic leukemia (ALL) cases. Fusion genes were also found in 2 MDS cases, of which AML1/ETO positive-MDS-RAEB progressed to AML rapidly.

    Conclusion: Screening of common fusion genes by multiplex RT-PCR is an important tool which could provide useful and reliable molecular genetic information for the diagnosis and treatment of leukemia.

    Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences 2005;37;3;236-9

  • The incidence of submicroscopic deletions in reciprocal translocations is similar in acute myeloid leukemia, BCR-ABL positive acute lymphoblastic leukemia, and chronic myeloid leukemia.

    Bacher U, Schnittger S, Kern W, Hiddemann W, Haferlach T and Schoch C

    We compared the incidence of submicroscopic deletions accompanying balanced translocations using interphase fluorescence in situ hybridization (FISH) in 245 patients with chronic myeloid leukemia (CML), 79 patients with acute lymphoblastic leukemia (ALL) and BCR-ABL (n=70) or MLL rearrangements (n=29), and 412 patients with acute myeloid leukemia (AML) with CBFB-MYH11 (n=122), PML-RARalpha (n=108), AML1-ETO (n=112), or MLL rearrangements (n=98). The incidence of submicroscopic deletions was 2-9% depending on the entity.

    Haematologica 2005;90;4;558-9

  • Multiplex real-time RT-PCR for prospective evaluation of WT1 and fusion gene transcripts in newly diagnosed de novo acute myeloid leukemia.

    Yanada M, Terakura S, Yokozawa T, Yamamoto K, Kiyoi H, Emi N, Kitamura K, Kohno A, Tanaka M, Tobita T, Takeo T, Sao H, Kataoka T, Kobayashi M, Takeshita A, Morishita Y, Naoe T and Sugiura I

    Department of Hematology, Nagoya University Graduate School of Medicine, Nagoya, Japan. myanada@med.nagoya-u.ac.jp

    Prognostic assessment is crucial for the management of AML. Although the use of karyotype analysis for risk-stratification is widely accepted, prognosis of AML remains ambiguous, particularly for patients categorized into the intermediate cytogenetic risk group and additional markers are required for an accurate prediction of outcome. For this study, we used multiplex real-time RT-PCR, which can simultaneously quantify WT1 and 10 distinct fusion gene transcripts, to prospectively evaluate the pre-treatment bone marrow findings of 53 de novo AML patients. Five patients with normal karyotype or insufficient metaphases detected by conventional karyotype analysis proved to have AML1-MTG8, CBFbeta-MYH11 or PML-RARalpha fusion transcripts. WT1 overexpression was observed in 92% of the patients, and the levels were significantly higher in the cytogenetic favorable risk group, especially patients with PML-RARalpha. WT1 levels also correlated with the percentage of blasts in bone marrow, especially in cases of core-binding factor leukemia. There was no association between initial WT1 levels and outcome in terms of event-free survival or overall survival. These results suggest that multiplex real-time RT-PCR is rapid and useful for the precise cytogenetic stratification of AML, and that WT1 levels at presentation correlate with several biologic features of leukemia, but have no prognostic significance.

    Leukemia & lymphoma 2004;45;9;1803-8

  • An inv(16)(p13q22) positive acute myeloid leukaemia relapsing as acute precursor B-cell lymphoblastic leukaemia.

    Boeckx N, van der Velden VH, Boogaerts M, Hagemeijer A, Vandenberghe P and van Dongen JJ

    Department of Laboratory Medicine, Laboratory of Haematology, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. nancy.boeckx@uz.kuleuven.ac.be

    We describe a case of a 38-year old male with inv(16)(p13q22) positive acute myeloid leukaemia (AML) with eosinophilia, relapsing after a molecular remission of almost three years. Remarkably, the leukaemia at relapse was identified as a precursor-B-cell acute lymphoblastic leukaemia (B-ALL) by cytology and immunophenotyping, but was inv(16)(p13q22) positive as revealed by interphase FISH, FICTION analysis, and real-time quantitative PCR. Analysis of immunoglobulin and T-cell receptor genes showed a bi-allelic DH2-JH rearrangement at relapse, but not at diagnosis. These findings indicate a myeloid to lymphoid lineage switch from an inv(16)(p13q22) positive leukaemia and show that IGH gene rearrangements can occur in the presence of CBFB-MYH11 fusion transcripts.

    Haematologica 2004;89;8;ECR28

  • Fluorescence in situ hybridization identifies cryptic t(16;16)(p13;q22) masked by del(16)(q22) in a case of AML-M4 Eo.

    Merchant SH, Haines S, Hall B, Hozier J and Viswanatha DS

    University of New Mexico Health Sciences Center, Department of Pathology, BRF Room 337C, 915 Camino de Salud, NE, Albuquerque, NM 87131. dviswanatha@salud.unm.edu

    We report a patient presenting with acute myeloid leukemia (AML)-M4 Eo, in whom conventional cytogenetic analysis revealed a 46, XY, del(16)(q22) karyotype. Molecular analysis of the bone marrow cells using reverse transcriptase polymerase chain reaction (RT-PCR) identified a CBFbeta-MYH11, "type A" fusion transcript. However, despite a thorough reevaluation, a balanced chromosome 16 abnormality could not be definitively identified by cytogenetics. Since there exists a small possibility of obtaining a false-positive PCR result, fluorescence in situ hybridization (FISH) analysis using dual-color, break-apart probes for CBFbeta was performed to elucidate the mechanism of fusion gene formation and thus confirm the RT-PCR results. FISH analysis clearly revealed a cryptic t(16;16), which was probably masked by the del(16)(q22). FISH is the preferred diagnostic procedure to elucidate the CBFbeta-MYH11 fusion in this situation, and resolves the possibility of both false-positive and false-negative results with RT-PCR technique. Due to the improved prognosis of AML associated with the CBFbeta-MYH11 fusion compared to AML generally, we recommend the use of FISH for detection of inv(16)/t(16;16)/CBFbeta-MYH11 in patients with failed, complex, or apparently normal cytogenetics, and in whom the cell morphology indicates the strong possibility of this gene fusion.

    The Journal of molecular diagnostics : JMD 2004;6;3;271-4

  • Childhood acute myeloid leukemia with CBFbeta-MYH11 rearrangement: study of incidence, morphology, cytogenetics, and clinical outcomes of Chinese in Hong Kong.

    Chan NP, Wong WS, Ng MH, Tsang KS, Lau TT, Leung Y, Chik KW, Shing MM and Li CK

    Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.

    We analyzed 43 consecutive cases of pediatric acute myeloid leukemia (AML) for the presence of the CBFbeta-MYH11 rearrangement using molecular techniques in a regional hospital in Hong Kong. Five cases (11.6%), 3 girls and 2 boys, ranging in age from 8 months to 14 years old, were found positive for the CBFbeta-MYH11 rearrangement. Morphologically, they were FAB M2 or M4 with or without eosinophilia (Eo). Typical M4Eo was observed in only one case. The molecular findings were in complete concordance with cytogenetic data, which revealed inv(16)(p13q22) in all and also gains of chromosome 4, 8, 22, and Y in one patient. Clinically, all 5 patients achieved complete remission after chemotherapy with favorable outcomes except for the patient with infantile AML, who relapsed 11 months after diagnosis, underwent cord blood transplantation, and was in second remission. This is the first clinicopathological study and documentation of the incidence of CBFbeta-MYH11 in childhood AML of Chinese in Hong Kong.

    American journal of hematology 2004;76;3;300-3

  • Translocation (11;13)(q23;q14) as the sole abnormality in a childhood de novo acute myelocytic leukemia.

    Tsang KS, Li CK, Lau TT, Wong AP, Leung Y and Ng MH

    Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing Street, Hong Kong, China. tsangks@cuhk.edu.hk

    We report a case of childhood de novo acute myelocytic leukemia (AML) with hyperleukocytosis with monoblastic features and deranged hemostasic function. G-band karyotyping demonstrated a previously unreported t(11;13)(q23;q14) in metaphase preparations from a fluorodeoxyuridine synchronized 1-day culture of leukophoresed cells. Multicolor fluorescence in situ hybridization revealed no cryptic rearrangements except for the translocation. Reverse transcriptase polymerase chain reaction showed no concomitant positivity of AML1/ETO, BCR/ABL, PML/RARA, and CBFbeta/MYH11 resulting from t(8;21)(q22;q22), t(9;22)(q34;q11), t(15;17)(q22;q11), and inv(16) (p13q22), respectively. This report of childhood de novo AML harboring t(11;13)(q23;q14) as the sole cytogenetic abnormality provides more data on the leukemogenesis of de novo AML with a 11q23 rearrangement.

    Cancer genetics and cytogenetics 2004;150;1;78-80

  • Molecular monitoring to identify a threshold of CBFbeta/MYH11 transcript below which continuous complete remission of acute myeloid leukemia inv16 is likely.

    Martinelli G, Rondoni M, Buonamici S, Ottaviani E, Piccaluga PP, Malagola M and Baccarani M

    Many patients with the inv(16) positive acute myeloid leukemia (AML) achieve complete remission (CR). Using real-time reverse transcriptase polymerase chain reaction (RT-PCR), we previously proposed critical CBFbeta-MYH11 transcript copy number thresholds to predict relapse or cure. We now update the molecular follow-up of our patients, also presenting the therapeutic management of these patients.

    Haematologica 2004;89;4;495-7

  • FLT3-activating mutations are associated with poor prognostic features in AML at diagnosis but they are not an independent prognostic factor.

    Chillón MC, Fernández C, García-Sanz R, Balanzategui A, Ramos F, Fernández-Calvo J, González M and Miguel JF

    Hematology Department, University Hospital of Salamanca, Salamanca, Spain.

    FLT3: gene alterations (internal tandem duplications - ITDs - and D835 mutations) are thought to be associated with poor-risk acute myeloid leukemia (AML). However, not all studies confirm this association, so it is still a matter of debate. Moreover, their association with other molecular abnormalities is less studied. We have investigated the presence of FLT3-ITD and D835 mutations in AML patients and their correlation with clinical and biological disease characteristics. The presence of ITD was analyzed in diagnostic samples of 176 AML patients and the D835 mutation in 135 of these patients. In all these patients, the presence of four well-known molecular abnormalities were also simultaneously characterized: PML/RARalpha, AML1/ETO, CBFbeta/MYH11 and MLL rearrangements. In all, 41 (23%) patients harbored FLT3 mutations, with 34 (19.3%) of them positive for the ITD, and seven (5%) positive for the D835 mutation. Of the acute promyelocytic leukemia (APL) patients, 16 (27%) showed FLT3 mutations, more frequently in M3 hypogranular cases (62% versus 17%, P=0.001) and cases with the short (bcr3) PML-RARalpha isoform (69%, P=0.002). In contrast, FLT3 was never altered in patients with inv(16), t(8;21) or 11q23 abnormalities. FLT3 mutations were significantly associated with some negative prognostic features at diagnosis (leukocytosis, high blast-cell percentage, and elevated LDH values), but they were not associated with different disease-free or overall survival. Therefore, we confirm a high frequency of FLT3 mutations in APL and in adult AML without recurrent cytogenetic translocations. In addition, they were not found as independent prognostic factors although associated with several adverse features at diagnosis.

    The hematology journal : the official journal of the European Haematology Association 2004;5;3;239-46

Literature (49)

Pubmed - human_disease

  • Detection of the CBFB/MYH11 fusion gene in de novo acute myeloid leukemia (AML): a single-institution study of 224 Japanese AML patients.

    Monma F, Nishii K, Shiga J, Sugahara H, Lorenzo F, Watanabe Y, Kawakami K, Hosokai N, Yamamori S, Katayama N and Shiku H

    Division of Hematology and Oncology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.

    The cytogenetic findings in acute myeloid leukemia (AML) are a powerful prognostic indicator. Among these abnormalities, the World Health Organization has classified inv(16)(p13q22), which is closely associated with the M4E classification in the French-American-British system, as indicating a good-risk AML. However, this chromosomal abnormality can often be difficult to detect. In this study, we used RT-PCR and FISH analysis to examine 224 Japanese adult de novo AML patients for the presence of the CBFB/MYH11 fusion transcript at the time of diagnosis. The CBFB/MYH11 fusion gene was detected in 17 patients (7.6%): eight patients had the inv(16) chromosome and in all of them it was M4E; nine patients did not have abnormalities in chromosome 16. AML with the CBFB/MYH11 fusion gene but without inv(16) was found in M2, M4, and M5, but not in M4E patients. There were no statistically significant differences in the clinical features of patients with the inv(16) and those with the cryptic inv(16) chromosome. These results indicate that even if eosinophilia is not found, molecular screening for CBFB/MYH11 fusion gene should be performed in all AML patients at the time of diagnosis to help guide disease management.

    Leukemia research 2007;31;4;471-6

  • Rare CBFB-MYH11 fusion transcripts in AML with inv(16)/t(16;16) are associated with therapy-related AML M4eo, atypical cytomorphology, atypical immunophenotype, atypical additional chromosomal rearrangements and low white blood cell count: a study on 162 patients.

    Schnittger S, Bacher U, Haferlach C, Kern W and Haferlach T

    MLL Munich Leukemia Laboratory, Munich, Germany. susanne.schnittger@mll-online.com

    The spectrum of CBFB-MYH11 fusion transcripts in acute myeloid leukemia (AML) M4eo with inv(16)/t(16;16) is heterogeneous. Approximately 85% show type A CBFB-MYH11 fusion transcripts. In addition, more than 10 different fusion transcripts have been reported. The prognostic impact and biological background of rare fusion transcripts remain open. In this study, a molecular characterization of CBFB-MYH11 transcripts in 162 patients with CBFB-MYH11 positive AML at diagnosis was performed. In total, 128 patients (79.0%) showed the fusion transcript type A, whereas nine different rare CBFB-MYH11 fusion genes were detected in 34 cases (21.0%). Rare fusion transcripts were found more frequently in therapy-related AML (P=0.0106). Numerical gains of the chromosomes 8, 21 and 22 were more frequently associated with type A (28.3%) than with rare fusions (12.9%) (P=0.012). Median white blood cell (WBC) count was higher in type A (35.4 G/l; range=1.1-279 G/l) than in cases with rare types (7.8 G/l; range=0.8-148.0 G/l) (P<0.0001). Rare fusion transcripts were correlated with an atypical cytomorphology not primarily suggestive for the FAB subtype M4eo (P=0.0203). Immunophenotype revealed lower CD2, CD13, CD33 and CD90 levels than in type A fusion cases (P=0.036, 0.002, 0.029 and 0.045, respectively). However, the type of fusion was not an independent prognostic parameter.

    Leukemia 2007;21;4;725-31

  • Granulocytic sarcoma of mesentery in acute myeloid leukemia with CBFB/MYH11 fusion gene but not inv(16) chromosome: case report and review of literature.

    Fujieda A, Nishii K, Tamaru T, Otsuki S, Kobayashi K, Monma F, Ohishi K, Nakase K, Katayama N and Shiku H

    Division of Hematology and Oncology, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.

    Granulocytic sarcoma (GS) is a rare extra-medullary tumor and usually involves the skin, soft tissue, and lymph nodes. GS is found in 8% of acute myeloid leukemia (AML) patients, especially patients with t(8;21)AML. It has been suggested that GS is a poor prognostic factor in t(8;21)AML. Compared to t(8;21)AML, GS is rare in cases of inv(16)AML. Thus, the characteristics of inv(16) with GS are not well understood. Here, we describe a patient with AML and mesentery GS. The chromosomal analysis was normal, but molecular analysis detected the CBFB/MYH11 fusion gene in the blasts. A complete remission was achieved with standard induction therapy followed by high-dose cytarabine consolidation. We have also summarized 12 reported cases of inv(16)AML with GS and found that GS was commonly found in abdominal lesions. These observations suggest that when abdominal GS is diagnosed, an analysis of the CBFB/MYH11 fusion gene is necessary to make an appropriate decision regarding treatment options, even if no chromosomal abnormalities are found.

    Leukemia research 2006;30;8;1053-7

  • Linkage of monogenic infantile hypertrophic pyloric stenosis to chromosome 16p12-p13 and evidence for genetic heterogeneity.

    Capon F, Reece A, Ravindrarajah R and Chung E

    Department of Paediatrics and Child Health, The Rayne Building, University College London, WC1E 6JJ London, UK.

    Infantile hypertrophic pyloric stenosis (IHPS) is the most common form of bowel obstruction in infancy. The disease affects males four times more often than females and is considered a paradigm for the sex-modified model of multifactorial inheritance. However, pedigrees consistent with autosomal dominant inheritance have also been documented. We analyzed a 3-generation family with IHPS including 10 affected individuals (5 males and 5 females) and mapped the underlying disease locus to chromosome 16p12-p13 (LOD score 3.23) by using a single-nucleotide polymorphism-based genomewide scan. The analysis of 10 additional multiplex pedigrees yielded negative or nonsignificant LOD scores, indicating the presence of locus heterogeneity. Sequence analysis of candidate genes from the chromosome 16 disease interval excluded the presence of pathogenic mutations in the GRIN2A and MYH11 genes.

    American journal of human genetics 2006;79;2;378-82

  • Therapy-related myelodysplastic syndrome with inv(16)(p13q22) and I type CBFbeta/MYH11 after autologous transplantation: undetectable fusion transcript in pretransplant progenitor cells.

    Yamamoto K, Nishikawa S, Minagawa K, Yakushijin K, Okamura A and Matsui T

    Hematology/Oncology, Department of Medicine, Kobe University Graduate School of Medicine, Chuo-ku, Kobe 650-0017, Japan.

    We describe here a unique case of therapy-related myelodysplastic syndrome (t-MDS) with inv(16)(p13q22) after autologous stem cell transplantation for lymphoma. The rare and smallest I type CBFbeta/MYH11 fusion transcript with a breakpoint at nucleotide 399 of CBFbeta and at nucleotide 2134 of MYH11 was detected in the bone marrow cells by reverse transcription polymerase chain reaction analysis. However, the fusion transcript was undetectable in the pretransplant peripheral blood stem cells. These results suggest that the stem cell damage leading to t-MDS may be induced mainly by the conditioning regimen for transplantation. Taken together with previous reports, the I type fusion transcript is preferentially induced with chemotherapy.

    Leukemia research 2006;30;3;354-61

  • Coexistence of inversion 16 and the Philadelphia chromosome in acute and chronic myeloid leukemias : report of six cases and review of literature.

    Wu Y, Slovak ML, Snyder DS and Arber DA

    Division of Pathology, City of Hope National Medical Center, Duarte, CA, USA.

    We report 5 cases of chronic myelogenous leukemia (CML) and 1 case of acute myeloid leukemia (AML) with the dual presence of t(9;22) and inv(16). The 6 patients were 5 men and 1 woman with a median age of 42.5 years. All cases were BCR-ABL+ with p210 products detected in all CML cases and a p190 product detected in the AML case. An increase in bone marrow eosinophils was detected in 3 of 5 cases, and abnormal eosinophils were identified in these 3 cases. The CBFbeta-MYH11 fusion gene was confirmed in all 3 CML cases and the 1 AML case tested, and this correlated with the presence of abnormal eosinophils with coarse basophilic granules. Of 5 patients with CML, 4 had a rapid transformation to myeloid accelerated phase of blast crisis. The coexistence of t(9;22) and inv(16) in CML seems to correlate with more rapid transformation.

    American journal of clinical pathology 2006;125;2;260-6

  • Prognostic value of minimal residual disease (MRD) in acute myeloid leukemia (AML) with favorable cytogenetics [t(8;21) and inv(16)].

    Perea G, Lasa A, Aventín A, Domingo A, Villamor N, Queipo de Llano MP, Llorente A, Juncà J, Palacios C, Fernández C, Gallart M, Font L, Tormo M, Florensa L, Bargay J, Martí JM, Vivancos P, Torres P, Berlanga JJ, Badell I, Brunet S, Sierra J, Nomdedéu JF and Grupo Cooperativo para el Estudio y Tratamiento de las Leucemias Agudas y Miel

    Hematology Department, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain.

    Most patients with acute myeloid leukemia (AML) and t(8;21) or inv(16) have a good prognosis with current anthracycline- and cytarabine-based protocols. Tandem analysis with flow cytometry (FC) and real-time RT-PCR (RQ-PCR) was applied to 55 patients, 28 harboring a t(8;21) and 27 an inv(16), including one case with a novel CBFbeta/MYH11 transcript. A total of 31% (n=17) of CR patients relapsed: seven with t(8;21) and 10 with inv(16). The mean amount of minimal residual disease (MRD) detected by FC in relapsed and nonrelapsed patients was markedly different: 0.3 vs 0.08% (P=0.002) at the end of treatment. The mean number of fusion transcript copies/ ABL x 10(4) also differed between relapsed and non-relapsed patients: 2385 vs 122 (P=0.001) after induction, 56 vs 7.6 after intensification (P=0.0001) and 75 vs 3.3 (P=0.0001) at the end of chemotherapy. Relapses were more common in patients with FC MRD level >0.1% at the end of treatment than in patients with < or = 0.1%: cumulative incidence of relapse (CIR) was 67 and 21% (P=0.03), respectively. Likewise, using RQ-PCR, a cutoff level of >10 copies at the end of treatment correlated with a high risk of relapse: CIR was 75% for patients with RQ-PCR >10 compared to 21% for patients with RQ-PCR levels < or = 10 (P=0.04). Combined use of FC and RQ-PCR may improve MRD detection, and provide useful clinical information on relapse kinetics in AML patients.

    Leukemia 2006;20;1;87-94

  • inv(16)(p13q22) in chronic myelogenous leukemia in blast phase: a clinicopathologic, cytogenetic, and molecular study of five cases.

    Merzianu M, Medeiros LJ, Cortes J, Yin C, Lin P, Jones D, Glassman A, Kantarjian H and Huh Y

    Department of Hematopathology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.

    Blast phase (BP) in chronic myelogenous leukemia (CML) frequently is accompanied by cytogenetic abnormalities in addition to t(9;22)(q34;q11.2). We describe 5 patients with CML in blast phase (CML-BP) in which t(9;22) and inv(16)(p13q22) were identified by conventional cytogenetics, with confirmation of BCR-ABL and CBFss-MYH11 by fluorescence in situ hybridization. The morphologic findings at the time of BP resembled de novo acute myeloid leukemia (AML) carrying inv(16)(p13q22), with abnormal eosinophils in the bone marrow and monocytosis in the peripheral blood in all cases. In 1 patient, inv(16)(p13q22) and abnormal eosinophils were detected in the bone marrow 2 months before CML-BP. The clinical course of these patients was similar to patients with CML-BP without evidence of inv(16)(p13q22). These cases illustrate that inv(16)(p13q22) is a form of cytogenetic evolution that rarely occurs in patients with CML at the time of BP. In this setting, unlike de novo AML, inv(16)(p13q22) in CML-BP is not associated with a favorable prognosis.

    American journal of clinical pathology 2005;124;5;807-14

  • [Role of molecular screening for common fusion genes in the diagnosis and classification of leukemia].

    Zhu YL, Zhang Y, Zhu P, Yang Y, Du JW and Liu J

    Department of Haematology, Peking University First Hospital, Beijing 100034, China.

    Objective: To assess the value of common fusion genes analysis in the diagnosis and classification of leukemia by multiplex RT-PCR.

    Methods: The multiplex RT-PCR, including 8 parallel PCR reactions, could screen 86 mRNA breakpoints or splice variants at the same time, which was important for the diagnosis and prognosis of leukemia. Bone marrow samples from 161 cases of leukemia and 8 cases of myelodysplastic syndrome (MDS) were involved in the study. The distribution of common fusion genes in leukemia was analyzed by the method mentioned above in combination with clinical and morphological features.

    Results: Ten fusion genes were detected in 115 cases of leukemia, including AML1/ETO, PML/RAR alpha, PLZF/RAR alpha, dupMLL, MLL/AF6, MLL/AF10, CBFbeta/MYH11, BCR/ABL, Hox11, and EVI1 BCR/ABL was positive in all the 52 cases of chronic myeloid leukemia; PML/RAR alpha was found in 21 of 25 acute promyelocytic leukemia (APL), and PLZF/RAR alpha was detected in one case of APL. Sixteen cases of 17 AML1/ETO-positive acute leukemia (AL) belonged to FAB-M2 subtype, and one case was mixed leukemia. Three of 4 AL cases carrying CBFbeta/MYH11 were M4 subtype, and one was M5 subtype. MLL aberrations were found in 16 AL, in which all MLL/AF6 translocation existed in M5 subtype with classic monoblastic characters. Furthermore, BCR/ABL was detected in 5 acute lymphoblastic leukemia (ALL) cases. Fusion genes were also found in 2 MDS cases, of which AML1/ETO positive-MDS-RAEB progressed to AML rapidly.

    Conclusion: Screening of common fusion genes by multiplex RT-PCR is an important tool which could provide useful and reliable molecular genetic information for the diagnosis and treatment of leukemia.

    Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences 2005;37;3;236-9

  • The incidence of submicroscopic deletions in reciprocal translocations is similar in acute myeloid leukemia, BCR-ABL positive acute lymphoblastic leukemia, and chronic myeloid leukemia.

    Bacher U, Schnittger S, Kern W, Hiddemann W, Haferlach T and Schoch C

    We compared the incidence of submicroscopic deletions accompanying balanced translocations using interphase fluorescence in situ hybridization (FISH) in 245 patients with chronic myeloid leukemia (CML), 79 patients with acute lymphoblastic leukemia (ALL) and BCR-ABL (n=70) or MLL rearrangements (n=29), and 412 patients with acute myeloid leukemia (AML) with CBFB-MYH11 (n=122), PML-RARalpha (n=108), AML1-ETO (n=112), or MLL rearrangements (n=98). The incidence of submicroscopic deletions was 2-9% depending on the entity.

    Haematologica 2005;90;4;558-9

  • Multiplex real-time RT-PCR for prospective evaluation of WT1 and fusion gene transcripts in newly diagnosed de novo acute myeloid leukemia.

    Yanada M, Terakura S, Yokozawa T, Yamamoto K, Kiyoi H, Emi N, Kitamura K, Kohno A, Tanaka M, Tobita T, Takeo T, Sao H, Kataoka T, Kobayashi M, Takeshita A, Morishita Y, Naoe T and Sugiura I

    Department of Hematology, Nagoya University Graduate School of Medicine, Nagoya, Japan. myanada@med.nagoya-u.ac.jp

    Prognostic assessment is crucial for the management of AML. Although the use of karyotype analysis for risk-stratification is widely accepted, prognosis of AML remains ambiguous, particularly for patients categorized into the intermediate cytogenetic risk group and additional markers are required for an accurate prediction of outcome. For this study, we used multiplex real-time RT-PCR, which can simultaneously quantify WT1 and 10 distinct fusion gene transcripts, to prospectively evaluate the pre-treatment bone marrow findings of 53 de novo AML patients. Five patients with normal karyotype or insufficient metaphases detected by conventional karyotype analysis proved to have AML1-MTG8, CBFbeta-MYH11 or PML-RARalpha fusion transcripts. WT1 overexpression was observed in 92% of the patients, and the levels were significantly higher in the cytogenetic favorable risk group, especially patients with PML-RARalpha. WT1 levels also correlated with the percentage of blasts in bone marrow, especially in cases of core-binding factor leukemia. There was no association between initial WT1 levels and outcome in terms of event-free survival or overall survival. These results suggest that multiplex real-time RT-PCR is rapid and useful for the precise cytogenetic stratification of AML, and that WT1 levels at presentation correlate with several biologic features of leukemia, but have no prognostic significance.

    Leukemia & lymphoma 2004;45;9;1803-8

  • An inv(16)(p13q22) positive acute myeloid leukaemia relapsing as acute precursor B-cell lymphoblastic leukaemia.

    Boeckx N, van der Velden VH, Boogaerts M, Hagemeijer A, Vandenberghe P and van Dongen JJ

    Department of Laboratory Medicine, Laboratory of Haematology, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. nancy.boeckx@uz.kuleuven.ac.be

    We describe a case of a 38-year old male with inv(16)(p13q22) positive acute myeloid leukaemia (AML) with eosinophilia, relapsing after a molecular remission of almost three years. Remarkably, the leukaemia at relapse was identified as a precursor-B-cell acute lymphoblastic leukaemia (B-ALL) by cytology and immunophenotyping, but was inv(16)(p13q22) positive as revealed by interphase FISH, FICTION analysis, and real-time quantitative PCR. Analysis of immunoglobulin and T-cell receptor genes showed a bi-allelic DH2-JH rearrangement at relapse, but not at diagnosis. These findings indicate a myeloid to lymphoid lineage switch from an inv(16)(p13q22) positive leukaemia and show that IGH gene rearrangements can occur in the presence of CBFB-MYH11 fusion transcripts.

    Haematologica 2004;89;8;ECR28

  • Fluorescence in situ hybridization identifies cryptic t(16;16)(p13;q22) masked by del(16)(q22) in a case of AML-M4 Eo.

    Merchant SH, Haines S, Hall B, Hozier J and Viswanatha DS

    University of New Mexico Health Sciences Center, Department of Pathology, BRF Room 337C, 915 Camino de Salud, NE, Albuquerque, NM 87131. dviswanatha@salud.unm.edu

    We report a patient presenting with acute myeloid leukemia (AML)-M4 Eo, in whom conventional cytogenetic analysis revealed a 46, XY, del(16)(q22) karyotype. Molecular analysis of the bone marrow cells using reverse transcriptase polymerase chain reaction (RT-PCR) identified a CBFbeta-MYH11, "type A" fusion transcript. However, despite a thorough reevaluation, a balanced chromosome 16 abnormality could not be definitively identified by cytogenetics. Since there exists a small possibility of obtaining a false-positive PCR result, fluorescence in situ hybridization (FISH) analysis using dual-color, break-apart probes for CBFbeta was performed to elucidate the mechanism of fusion gene formation and thus confirm the RT-PCR results. FISH analysis clearly revealed a cryptic t(16;16), which was probably masked by the del(16)(q22). FISH is the preferred diagnostic procedure to elucidate the CBFbeta-MYH11 fusion in this situation, and resolves the possibility of both false-positive and false-negative results with RT-PCR technique. Due to the improved prognosis of AML associated with the CBFbeta-MYH11 fusion compared to AML generally, we recommend the use of FISH for detection of inv(16)/t(16;16)/CBFbeta-MYH11 in patients with failed, complex, or apparently normal cytogenetics, and in whom the cell morphology indicates the strong possibility of this gene fusion.

    The Journal of molecular diagnostics : JMD 2004;6;3;271-4

  • Childhood acute myeloid leukemia with CBFbeta-MYH11 rearrangement: study of incidence, morphology, cytogenetics, and clinical outcomes of Chinese in Hong Kong.

    Chan NP, Wong WS, Ng MH, Tsang KS, Lau TT, Leung Y, Chik KW, Shing MM and Li CK

    Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.

    We analyzed 43 consecutive cases of pediatric acute myeloid leukemia (AML) for the presence of the CBFbeta-MYH11 rearrangement using molecular techniques in a regional hospital in Hong Kong. Five cases (11.6%), 3 girls and 2 boys, ranging in age from 8 months to 14 years old, were found positive for the CBFbeta-MYH11 rearrangement. Morphologically, they were FAB M2 or M4 with or without eosinophilia (Eo). Typical M4Eo was observed in only one case. The molecular findings were in complete concordance with cytogenetic data, which revealed inv(16)(p13q22) in all and also gains of chromosome 4, 8, 22, and Y in one patient. Clinically, all 5 patients achieved complete remission after chemotherapy with favorable outcomes except for the patient with infantile AML, who relapsed 11 months after diagnosis, underwent cord blood transplantation, and was in second remission. This is the first clinicopathological study and documentation of the incidence of CBFbeta-MYH11 in childhood AML of Chinese in Hong Kong.

    American journal of hematology 2004;76;3;300-3

  • Translocation (11;13)(q23;q14) as the sole abnormality in a childhood de novo acute myelocytic leukemia.

    Tsang KS, Li CK, Lau TT, Wong AP, Leung Y and Ng MH

    Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing Street, Hong Kong, China. tsangks@cuhk.edu.hk

    We report a case of childhood de novo acute myelocytic leukemia (AML) with hyperleukocytosis with monoblastic features and deranged hemostasic function. G-band karyotyping demonstrated a previously unreported t(11;13)(q23;q14) in metaphase preparations from a fluorodeoxyuridine synchronized 1-day culture of leukophoresed cells. Multicolor fluorescence in situ hybridization revealed no cryptic rearrangements except for the translocation. Reverse transcriptase polymerase chain reaction showed no concomitant positivity of AML1/ETO, BCR/ABL, PML/RARA, and CBFbeta/MYH11 resulting from t(8;21)(q22;q22), t(9;22)(q34;q11), t(15;17)(q22;q11), and inv(16) (p13q22), respectively. This report of childhood de novo AML harboring t(11;13)(q23;q14) as the sole cytogenetic abnormality provides more data on the leukemogenesis of de novo AML with a 11q23 rearrangement.

    Cancer genetics and cytogenetics 2004;150;1;78-80

  • Molecular monitoring to identify a threshold of CBFbeta/MYH11 transcript below which continuous complete remission of acute myeloid leukemia inv16 is likely.

    Martinelli G, Rondoni M, Buonamici S, Ottaviani E, Piccaluga PP, Malagola M and Baccarani M

    Many patients with the inv(16) positive acute myeloid leukemia (AML) achieve complete remission (CR). Using real-time reverse transcriptase polymerase chain reaction (RT-PCR), we previously proposed critical CBFbeta-MYH11 transcript copy number thresholds to predict relapse or cure. We now update the molecular follow-up of our patients, also presenting the therapeutic management of these patients.

    Haematologica 2004;89;4;495-7

  • FLT3-activating mutations are associated with poor prognostic features in AML at diagnosis but they are not an independent prognostic factor.

    Chillón MC, Fernández C, García-Sanz R, Balanzategui A, Ramos F, Fernández-Calvo J, González M and Miguel JF

    Hematology Department, University Hospital of Salamanca, Salamanca, Spain.

    FLT3: gene alterations (internal tandem duplications - ITDs - and D835 mutations) are thought to be associated with poor-risk acute myeloid leukemia (AML). However, not all studies confirm this association, so it is still a matter of debate. Moreover, their association with other molecular abnormalities is less studied. We have investigated the presence of FLT3-ITD and D835 mutations in AML patients and their correlation with clinical and biological disease characteristics. The presence of ITD was analyzed in diagnostic samples of 176 AML patients and the D835 mutation in 135 of these patients. In all these patients, the presence of four well-known molecular abnormalities were also simultaneously characterized: PML/RARalpha, AML1/ETO, CBFbeta/MYH11 and MLL rearrangements. In all, 41 (23%) patients harbored FLT3 mutations, with 34 (19.3%) of them positive for the ITD, and seven (5%) positive for the D835 mutation. Of the acute promyelocytic leukemia (APL) patients, 16 (27%) showed FLT3 mutations, more frequently in M3 hypogranular cases (62% versus 17%, P=0.001) and cases with the short (bcr3) PML-RARalpha isoform (69%, P=0.002). In contrast, FLT3 was never altered in patients with inv(16), t(8;21) or 11q23 abnormalities. FLT3 mutations were significantly associated with some negative prognostic features at diagnosis (leukocytosis, high blast-cell percentage, and elevated LDH values), but they were not associated with different disease-free or overall survival. Therefore, we confirm a high frequency of FLT3 mutations in APL and in adult AML without recurrent cytogenetic translocations. In addition, they were not found as independent prognostic factors although associated with several adverse features at diagnosis.

    The hematology journal : the official journal of the European Haematology Association 2004;5;3;239-46

Pubmed - other

  • Mammalian BTBD12/SLX4 assembles a Holliday junction resolvase and is required for DNA repair.

    Svendsen JM, Smogorzewska A, Sowa ME, O'Connell BC, Gygi SP, Elledge SJ and Harper JW

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

    Structure-specific endonucleases mediate cleavage of DNA structures formed during repair of collapsed replication forks and double-strand breaks (DSBs). Here, we identify BTBD12 as the human ortholog of the budding yeast DNA repair factor Slx4p and D. melanogaster MUS312. Human SLX4 forms a multiprotein complex with the ERCC4(XPF)-ERCC1, MUS81-EME1, and SLX1 endonucleases and also associates with MSH2/MSH3 mismatch repair complex, telomere binding complex TERF2(TRF2)-TERF2IP(RAP1), the protein kinase PLK1 and the uncharacterized protein C20orf94. Depletion of SLX4 causes sensitivity to mitomycin C and camptothecin and reduces the efficiency of DSB repair in vivo. SLX4 complexes cleave 3' flap, 5' flap, and replication fork structures; yet unlike other endonucleases associated with SLX4, the SLX1-SLX4 module promotes symmetrical cleavage of static and migrating Holliday junctions (HJs), identifying SLX1-SLX4 as a HJ resolvase. Thus, SLX4 assembles a modular toolkit for repair of specific types of DNA lesions and is critical for cellular responses to replication fork failure.

    Funded by: Howard Hughes Medical Institute; NCI NIH HHS: T32 CA009216, T32CA09216; NIA NIH HHS: R01 AG011085, R01 AG011085-16; NIGMS NIH HHS: R01 GM070565, R01 GM070565-04

    Cell 2009;138;1;63-77

  • Myosin, transgelin, and myosin light chain kinase: expression and function in asthma.

    Léguillette R, Laviolette M, Bergeron C, Zitouni N, Kogut P, Solway J, Kachmar L, Hamid Q and Lauzon AM

    Meakins-Christie Laboratories, McGill University, 3626 St-Urbain street, Montreal, PQ, H2X 2P2 Canada.

    Rationale: Airway smooth muscle (SM) of patients with asthma exhibits a greater velocity of shortening (Vmax) than that of normal subjects, and this is thought to contribute to airway hyperresponsiveness. A greater Vmax can result from increased myosin activation. This has been reported in sensitized human airway SM and in models of asthma. A faster Vmax can also result from the expression of specific contractile proteins that promote faster cross-bridge cycling. This possibility has never been addressed in asthma.

    Objectives: We tested the hypothesis that the expression of genes coding for SM contractile proteins is altered in asthmatic airways and contributes to their increased Vmax.

    Methods: We quantified the expression of several genes that code for SM contractile proteins in mild allergic asthmatic and control human airway endobronchial biopsies. The function of these contractile proteins was tested using the in vitro motility assay.

    We observed an increased expression of the fast myosin heavy chain isoform, transgelin, and myosin light chain kinase in patients with asthma. Immunohistochemistry demonstrated the expression of these genes at the protein level. To address the functional significance of this overexpression, we purified tracheal myosin from the hyperresponsive Fisher rats, which also overexpress the fast myosin heavy chain isoform as compared with the normoresponsive Lewis rats, and found a faster rate of actin filament propulsion. Conversely, transgelin did not alter the rate of actin filament propulsion.

    Conclusions: Selective overexpression of airway smooth muscle genes in asthmatic airways leads to increased Vmax, thus contributing to the airway hyperresponsiveness observed in asthma.

    American journal of respiratory and critical care medicine 2009;179;3;194-204

  • Smooth-muscle myosin mutations in hereditary non-polyposis colorectal cancer syndrome.

    Vickaryous N, Polanco-Echeverry G, Morrow S, Suraweera N, Thomas H, Tomlinson I and Silver A

    Colorectal Cancer Genetics, Institute for Cell and Molecular Sciences, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Whitechapel, London, UK.

    We examined adenomas and cancers from hereditary non-polyposis colorectal cancer (HNPCC) syndrome patients for the presence of frameshift mutations in the smooth-muscle myosin gene, MYH11. Our results show that mutations in MYH11 occur more frequently in cancers than adenomas (P=0.008) and are dependent on microsatellite instability (MSI+).

    Funded by: Cancer Research UK

    British journal of cancer 2008;99;10;1726-8

  • Somatic mutation analysis of MYH11 in breast and prostate cancer.

    Alhopuro P, Karhu A, Winqvist R, Waltering K, Visakorpi T and Aaltonen LA

    Department of Medical Genetics and Translational Genome-Scale Biology Research Program, University of Helsinki, Helsinki, Finland. pia.alhopuro@helsinki.fi

    Background: MYH11 (also known as SMMHC) encodes the smooth-muscle myosin heavy chain, which has a key role in smooth muscle contraction. Inversion at the MYH11 locus is one of the most frequent chromosomal aberrations found in acute myeloid leukemia. We have previously shown that MYH11 mutations occur in human colorectal cancer, and may also be associated with Peutz-Jeghers syndrome. The mutations found in human intestinal neoplasia result in unregulated proteins with constitutive motor activity, similar to the mutant myh11 underlying the zebrafish meltdown phenotype characterized by disrupted intestinal architecture. Recently, MYH1 and MYH9 have been identified as candidate breast cancer genes in a systematic analysis of the breast cancer genome.

    Methods: The aim of this study was to investigate the role of somatic MYH11 mutations in two common tumor types; breast and prostate cancers. A total of 155 breast cancer and 71 prostate cancer samples were analyzed for those regions in MYH11 (altogether 8 exons out of 42 coding exons) that harboured mutations in colorectal cancer in our previous study.

    Results: In breast cancer samples only germline alterations were observed. One prostate cancer sample harbored a frameshift mutation c.5798delC, which we have previously shown to result in a protein with unregulated motor activity.

    Conclusion: Little evidence for a role of somatic MYH11 mutations in the formation of breast or prostate cancers was obtained in this study.

    BMC cancer 2008;8;263

  • Mutation analysis of MYH11 in acute myeloid leukemia.

    Sammalkorpi H, Alhopuro P, Niittymäki I, Orntoft TF, Hokland P, Karhu A and Aaltonen LA

    Leukemia & lymphoma 2008;49;9;1829-31

  • Unregulated smooth-muscle myosin in human intestinal neoplasia.

    Alhopuro P, Phichith D, Tuupanen S, Sammalkorpi H, Nybondas M, Saharinen J, Robinson JP, Yang Z, Chen LQ, Orntoft T, Mecklin JP, Järvinen H, Eng C, Moeslein G, Shibata D, Houlston RS, Lucassen A, Tomlinson IP, Launonen V, Ristimäki A, Arango D, Karhu A, Sweeney HL and Aaltonen LA

    Department of Medical Genetics and Division of Pathology, HUSLAB and Haartman Institute, Helsinki University Central Hospital and Genome Scale Biology Program, Biomedicum Helsinki, University of Helsinki, 00014, Helsinki, Finland.

    A recent study described a recessive ATPase activating germ-line mutation in smooth-muscle myosin (smmhc/myh11) underlying the zebrafish meltdown (mlt) phenotype. The mlt zebrafish develops intestinal abnormalities reminiscent of human Peutz-Jeghers syndrome (PJS) and juvenile polyposis (JP). To examine the role of MYH11 in human intestinal neoplasia, we searched for MYH11 mutations in patients with colorectal cancer (CRC), PJS and JP. We found somatic protein-elongating frameshift mutations in 55% of CRCs displaying microsatellite instability and in the germ-line of one individual with PJS. Additionally, two somatic missense mutations were found in one microsatellite stable CRC. These two missense mutations, R501L and K1044N, and the frameshift mutations were functionally evaluated. All mutations resulted in unregulated molecules displaying constitutive motor activity, similar to the mutant myosin underlying mlt. Thus, MYH11 mutations appear to contribute also to human intestinal neoplasia. Unregulated MYH11 may affect the cellular energy balance or disturb cell lineage decisions in tumor progenitor cells. These data challenge our view on MYH11 as a passive differentiation marker functioning in muscle contraction and add to our understanding of intestinal neoplasia.

    Proceedings of the National Academy of Sciences of the United States of America 2008;105;14;5513-8

  • Investigation of the MYH11 gene in sporadic patients with an isolated persistently patent arterial duct.

    Zhu L, Bonnet D, Boussion M, Vedie B, Sidi D and Jeunemaitre X

    AP-HP, Hôpital Européen George Pompidou, Départment de Génétique, 75015, Paris, France.

    Persistent patency of the arterial duct is one of the most common congenital cardiac malformations. We recently showed that mutations in the MYH11 gene result in a disease combining familial thoracic aortic aneurysm and dissection, along with patency of the arterial duct. It is also known that the smooth muscle myosin heavy chain is involved in the physiological closure of the arterial duct. With this in mind, we investigated whether the MYH11 gene was a susceptibility gene for sporadic occurrence of isolated persistent patency of the arterial duct. We sequenced the entire coding sequence of the MYH11 gene in 60 Caucasian children with persistent patency born after 36 weeks of gestation. The frequencies of rare genetic variants, and single nucleotide polymorphisms, were compared with 192 normal controls. Two possible functional missense mutations were found in two affected individuals. Another rare variant, specifically p.Arg1535Gln, and two coding polymorphisms, namely p.Ala1234Thr and p.Val1289Ala, had allele frequencies similar to those in controls. Haplotype analysis after estimating linkage disequilibrium was carried out using six polymorphisms. Individual genotypes were distributed similarly among cases and controls. Only one of the seven major haplotypes was significantly less frequent among cases, at 0.07, than among controls, when the figure was 0.22 (OR 0.23 [0.08-0.27]). Our findings suggest that the MYH11 gene is involved in only rare instances when persistent patency of the arterial duct occurs in sporadic fashion.

    Cardiology in the young 2007;17;6;666-72

  • MYH11 mutations result in a distinct vascular pathology driven by insulin-like growth factor 1 and angiotensin II.

    Pannu H, Tran-Fadulu V, Papke CL, Scherer S, Liu Y, Presley C, Guo D, Estrera AL, Safi HJ, Brasier AR, Vick GW, Marian AJ, Raman CS, Buja LM and Milewicz DM

    Department of Internal Medicine and Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.

    Non-syndromic thoracic aortic aneurysms and dissections (TAADs) are inherited in an autosomal dominant manner in approximately 20% of cases. Familial TAAD is genetically heterogeneous and four loci have been mapped for this disease to date, including a locus at 16p for TAAD associated with patent ductus arteriosus (PDA). The defective gene at the 16p locus has recently been identified as the smooth muscle cell (SMC)-specific myosin heavy chain gene (MYH11). On sequencing MYH11 in 93 families with TAAD alone and three families with TAAD/PDA, we identified novel mutations in two families with TAAD/PDA, but none in families with TAAD alone. Histopathological analysis of aortic sections from two individuals with MYH11 mutations revealed SMC disarray and focal hyperplasia of SMCs in the aortic media. SMC hyperplasia leading to significant lumen narrowing in some of the vessels of the adventitia was also observed. Insulin-like growth factor-1 (IGF-1) was upregulated in mutant aortas as well as explanted SMCs, but no increase in transforming growth factor-beta expression or downstream targets was observed. Enhanced expression of angiotensin-converting enzyme and markers of Angiotensin II (Ang II) vascular inflammation (macrophage inflammatory protein-1alpha and beta) were also found. These data suggest that MYH11 mutations are likely to be specific to the phenotype of TAAD/PDA and result in a distinct aortic and occlusive vascular pathology potentially driven by IGF-1 and Ang II.

    Funded by: NCRR NIH HHS: M01 RR002558, M01RR02558, S10 RR019186, S10 RR19186; NHLBI NIH HHS: P50HL08379-01, R01 HL062594, R01 HL068884, R01 HL068884-05, R01 HL088498, R01 HL088498-01A1, R01 HL62594

    Human molecular genetics 2007;16;20;2453-62

  • Comparative analysis of genes regulated in acute myelomonocytic leukemia with and without inv(16)(p13q22) using microarray techniques, real-time PCR, immunohistochemistry, and flow cytometry immunophenotyping.

    Sun X, Zhang W, Ramdas L, Stivers DN, Jones DM, Kantarjian HM, Estey EH, Vadhan-Raj S, Medeiros LJ and Bueso-Ramos CE

    Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.

    Acute myeloid leukemia with inv(16)(p13q22), also known as M4Eo, is a distinct type of leukemia with characteristic clinicopathologic and cytogenetic features. Patients with M4Eo have monocytosis, high blast counts, and abnormal bone marrow eosinophils that contain large basophilic granules. The inv(16)(p13q22) or, less commonly, the t(16;16)(p13;q22) causes fusion of the CBFbeta gene at 16q22 and the MYH11 gene at 16p13, creating the novel chimeric protein CBFbeta-MYH11. To understand the underlying molecular mechanisms unique to M4Eo biology, we determined the gene expression profile of M4Eo cases by using cDNA and long oligonucleotide microarrays. Cases of acute myelomonocytic leukemia without CBFbeta-MYH11 (M4) acted as our control. We found that in the gene expression profile of M4Eo, NF-kappaB activators and inhibitors were upregulated and downregulated, respectively, suggesting that the NF-kappaB signaling pathway is activated at a higher level in M4Eo than in acute myelomonocytic leukemia M4. In addition, the gene expression profile of M4Eo indicates high cell proliferation and low apoptosis. We used real-time PCR, immunohistochemistry, and flow cytometry immunophenotyping to confirm some of our microarray data. These findings most likely represent the functional consequences of the abnormal chimeric protein CBFbeta-MYH11, which is unique to this disease, and suggest that NF-kappaB is a potential therapeutic target for treating M4Eo patients.

    Funded by: NCI NIH HHS: 5P30 CA016672-28

    Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc 2007;20;8;811-20

  • Identification of a region on the outer surface of the CBFbeta-SMMHC myeloid oncoprotein assembly competence domain critical for multimerization.

    Zhang L, D'Costa J, Kummalue T, Civin CI and Friedman AD

    Divisions of Pediatric Oncology and Immunology and Hematopoiesis, Johns Hopkins University, Baltimore, MD 21231, USA.

    In the core binding factor (CBF)beta-smooth muscle myosin heavy chain (SMMHC) acute myeloid leukemia (AML) oncoprotein, CBFbeta lies N-terminal to the alpha-helical rod domain of SMMHC. Deletion of the SMMHC assembly competence domain (ACD), conserved among skeletal, smooth and nonmuscle myosins, prevents multimerization, inhibition of CBF and inhibition of cell proliferation. To define the amino acids critical for ACD function, three outer surface residues of ACD helices A-D, the subsequent helices E-H or the more N-terminal X or Z helices were now mutated. Variants were assessed for multimerization in low ionic strength in vitro and for nuclear localization as a measure of in vivo multimerization. Mutation of individual helices C-H reduced multimerization, with alteration of the outer surface of helices D or E having the greatest effect. The ability of these SMMHC variants to slow murine myeloid progenitor proliferation largely paralleled their effects on multimerization. Divergence at the boundaries of the ACD may reflect quantitative differences between in vitro and in vivo filament assembly. Each helix mutant retained the ability to bind the mSin3A corepressor. Agents interacting with the outer surface of the CBFbeta-SMMHC ACD that prevent multimerization may be effective as novel therapeutics in AML.

    Funded by: NCI NIH HHS: CA070970, CA098805

    Oncogene 2006;25;55;7289-96

  • 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

  • Mutations in myosin heavy chain 11 cause a syndrome associating thoracic aortic aneurysm/aortic dissection and patent ductus arteriosus.

    Zhu L, Vranckx R, Khau Van Kien P, Lalande A, Boisset N, Mathieu F, Wegman M, Glancy L, Gasc JM, Brunotte F, Bruneval P, Wolf JE, Michel JB and Jeunemaitre X

    Assistance Publique Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Département de Génétique, 75015 Paris, France.

    We have recently described two kindreds presenting thoracic aortic aneurysm and/or aortic dissection (TAAD) and patent ductus arteriosus (PDA) and mapped the disease locus to 16p12.2-p13.13 (ref. 3). We now demonstrate that the disease is caused by mutations in the MYH11 gene affecting the C-terminal coiled-coil region of the smooth muscle myosin heavy chain, a specific contractile protein of smooth muscle cells (SMC). All individuals bearing the heterozygous mutations, even if asymptomatic, showed marked aortic stiffness. Examination of pathological aortas showed large areas of medial degeneration with very low SMC content. Abnormal immunological recognition of SM-MHC and the colocalization of wild-type and mutant rod proteins in SMC, in conjunction with differences in their coimmunoprecipitation capacities, strongly suggest a dominant-negative effect. Human MYH11 gene mutations provide the first example of a direct change in a specific SMC protein leading to an inherited arterial disease.

    Nature genetics 2006;38;3;343-9

  • Diagnosis and monitoring of CBFB-MYH11-positive acute myeloid leukemia by qualitative and quantitative RT-PCR.

    van der Reijden BA and Jansen JH

    Central Hematology Laboratory, University Medical Center St Raboud, Nijmegen, The Netherlands.

    During the last decade, many mutations present in myeloid leukemias have been molecularly characterized. Several of these mutations have clear prognostic impact. The molecular screening of these mutations has now become an essential part in several risk-adapted international clinical trials. Here we describe protocols for the qualitative and quantitative detection of leukemic cells that are characterized by a CBFB-MYH11 gene fusion.

    Methods in molecular medicine 2006;125;163-75

  • (+)Insert smooth muscle myosin heavy chain (SM-B) isoform expression in human tissues.

    Léguillette R, Gil FR, Zitouni N, Lajoie-Kadoch S, Sobieszek A and Lauzon AM

    Meakins-Christie Laboratories, McGill University, 3626 St-Urbain St., Montréal, QC, Canada, H2X 2P2.

    Two smooth muscle myosin heavy chain isoforms differ in their amino terminus by the presence [(+)insert] or absence [(-)insert] of a seven-amino acid insert. Animal studies show that the (+)insert isoform is predominantly expressed in rapidly contracting phasic muscle and the (-)insert isoform is mostly found in slowly contracting tonic muscle. The expression of the (+)insert isoform has never been demonstrated in human smooth muscle. We hypothesized that the (+)insert isoform is present in humans and that its expression is commensurate with the organ's functional requirements. We report, for the first time, the sequence of the human (+)insert isoform and quantification of its expression by real-time PCR and Western blot analysis in a panel of human organs. The (+)insert isoform mRNA and protein expression levels are significantly greater in small intestine compared with all organs studied except for trachea and are significantly greater in trachea compared with uterus and aorta. To assess the functional significance of this differential myosin isoform expression between organs, we measured the rate of actin filament movement (nu(max)) when propelled by myosin purified from rat organs, because the rat and human inserts are identical and their remaining sequences show 93% identity. nu(max) exhibits a rank correlation from the most tonic to the most phasic organ. The selective expression of the (+)insert isoform observed among human organs suggests that it is an important determinant of tissue shortening velocity. A differential expression of the (+)insert isoform could also account for altered contractile properties observed in human pathology.

    American journal of physiology. Cell physiology 2005;289;5;C1277-85

  • Plag1 and Plagl2 are oncogenes that induce acute myeloid leukemia in cooperation with Cbfb-MYH11.

    Landrette SF, Kuo YH, Hensen K, Barjesteh van Waalwijk van Doorn-Khosrovani S, Perrat PN, Van de Ven WJ, Delwel R and Castilla LH

    Program in Gene Function and Expression, University of Massachusetts Medical School, 364 Plantation St, LRB/622, Worcester, MA 01605, USA.

    Recurrent chromosomal rearrangements are associated with the development of acute myeloid leukemia (AML). The frequent inversion of chromosome 16 creates the CBFB-MYH11 fusion gene that encodes the fusion protein CBFbeta-SMMHC. This fusion protein inhibits the core-binding factor (CBF), resulting in a block of hematopoietic differentiation, and induces leukemia upon the acquisition of additional mutations. A recent genetic screen identified Plag1 and Plagl2 as CBF beta-SMMHC candidate cooperating proteins. In this study, we demonstrate that Plag1 and Plagl2 independently cooperate with CBF beta-SMMHC in vivo to efficiently trigger leukemia with short latency in the mouse. In addition, Plag1 and Plagl2 increased proliferation by inducing G1 to S transition that resulted in the expansion of hematopoietic progenitors and increased cell renewal in vitro. Finally, PLAG1 and PLAGL2 expression was increased in 20% of human AML samples. Interestingly, PLAGL2 was preferentially increased in samples with chromosome 16 inversion, suggesting that PLAG1 and PLAGL2 may also contribute to human AML. Overall, this study shows that Plag1 and Plagl2 are novel leukemia oncogenes that act by expanding hematopoietic progenitors expressing CbF beta-SMMHC.

    Funded by: NCI NIH HHS: R01 CA096983-01

    Blood 2005;105;7;2900-7

  • 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

  • Smooth muscle contraction and relaxation.

    Webb RC

    Department of Physiology, Medical College of Georgia, Augusta, Georgia 30912, USA. cwebb@mcg.edu

    This brief review serves as a refresher on smooth muscle physiology for those educators who teach in medical and graduate courses of physiology. Additionally, those professionals who are in need of an update on smooth muscle physiology may find this review to be useful. Smooth muscle lacks the striations characteristic of cardiac and skeletal muscle. Layers of smooth muscle cells line the walls of various organs and tubes in the body, and the contractile function of smooth muscle is not under voluntary control. Contractile activity in smooth muscle is initiated by a Ca(2+)-calmodulin interaction to stimulate phosphorylation of the light chain of myosin. Ca(2+) sensitization of the contractile proteins is signaled by the RhoA/Rho kinase pathway to inhibit the dephosphorylation of the light chain by myosin phosphatase, thereby maintaining force generation. Removal of Ca(2+) from the cytosol and stimulation of myosin phosphatase initiate the process of smooth muscle relaxation.

    Funded by: NHLBI NIH HHS: HL-18575, HL-71138

    Advances in physiology education 2003;27;1-4;201-6

  • Role of Cbfb in hematopoiesis and perturbations resulting from expression of the leukemogenic fusion gene Cbfb-MYH11.

    Kundu M, Chen A, Anderson S, Kirby M, Xu L, Castilla LH, Bodine D and Liu PP

    Genetics and Molecular Biology Branch and Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA.

    Core-binding factor beta (CBFbeta) and CBFalpha2 form a heterodimeric transcription factor that plays an important role in hematopoiesis. The genes encoding either CBFbeta or CBFalpha2 are involved in chromosomal rearrangements in more than 30% of cases of acute myeloid leukemia (AML), suggesting that CBFbeta and CBFalpha2 play important roles in leukemogenesis. Inv(16)(p13;q22) is found in almost all cases of AML M4Eo and results in the fusion of CBFB with MYH11, the gene encoding smooth muscle myosin heavy chain. Mouse embryos heterozygous for a Cbfb-MYH11 knock-in gene lack definitive hematopoiesis, a phenotype shared by Cbfb(-/-) embryos. In this study we generated a Cbfb-GFP knock-in mouse model to characterize the normal expression pattern of Cbfbeta in hematopoietic cells. In midgestation embryos, Cbfbeta was expressed in populations enriched for hematopoietic stem cells and progenitors. This population of stem cells and progenitors was not present in mouse embryos heterozygous for the Cbfb-MYH11 knock-in gene. Together, these data suggest that Cbfb-MYH11 blocks embryonic hematopoiesis at the stem-progenitor cell level and that Cbfb is essential for the generation of hematopoietic stem and progenitor cells. In adult mice, Cbfbeta was expressed in stem and progenitor cells, as well as mature myeloid and lymphoid cells. Although it was expressed in erythroid progenitors, Cbfbeta was not expressed during the terminal stages of erythropoiesis. Our data indicate that Cbfb is required for myeloid and lymphoid differentiation; but does not play a critical role in erythroid differentiation.

    Blood 2002;100;7;2449-56

  • Pseudoxanthoma elasticum: Point mutations in the ABCC6 gene and a large deletion including also ABCC1 and MYH11.

    Meloni I, Rubegni P, De Aloe G, Bruttini M, Pianigiani E, Cusano R, Seri M, Mondillo S, Federico A, Bardelli AM, Andreassi L, Fimiani M and Renieri A

    Genetica Medica, University of Siena, Siena, Italy.

    Pseudoxanthoma elasticum (PXE) is a mendelian disorder characterized by calcification of elastic fibers in skin, arteries, and retina. It results in dermal lesions, arterial insufficiency and retinal hemorrhages, leading to macular degeneration. PXE is transmitted either as an autosomal dominant or recessive trait and several sporadic cases have been observed. Mutations in the ABCC6 gene have been identified very recently in patients. Here, we report on a large Italian family affected by pseudoxanthoma elasticum for which linkage analysis had pointed to a region encompassing markers D16S3069-D16S405-D16S3103; hemizygosity of marker D16S405 allowed us to detect a submicroscopic deletion of at least 900 kb involving ABCC6, ABCC1, and MYH11. Mutation analysis on the other allele of the family, as well as on two additional sporadic cases, revealed nonsense (Y227X, R518X, R1164X) and frame-shift (c.960delC) mutations in ABCC6 (MRP6) further confirming the role of this multi-drug resistance gene in the etiology of pseudoxanthoma elasticum. Furthermore, clinical re-examination of members of the family harboring the deletion led to the detection of additional features, potentially caused by the deletion of the MYH11 gene. In the course of the analysis five nonpathogenic variants were found in ABCC6: 1233T>C, 1245G>A, 1838 T>G (V614A), 1890C>G, and 3506+83C>A. Hum Mutat 18:85, 2001.

    Human mutation 2001;18;1;85

  • Smooth muscle myosin heavy chain isoforms and their role in muscle physiology.

    Babu GJ, Warshaw DM and Periasamy M

    Laboratory of Molecular Cardiology, Division of Cardiology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, USA.

    Unlike vertebrate skeletal muscle, smooth muscle myosin heavy chain isoforms are encoded by a single gene. Alternative splicing of the primary transcript from a single gene generates four smooth muscle myosin heavy chain isoforms. These isoforms differ both at the carboxyl terminus (SM1 and SM2 isoforms) and at the amino terminus (SM-A and SM-B isoforms). The smooth muscle myosin heavy chain isoforms are differentially expressed during smooth muscle development and in different smooth muscle cell types. The mechanical properties of smooth muscle may be correlated with the myosin heavy chain content/isoform expression. However, the precise function of each smooth muscle myosin heavy chain isoform to muscle contraction remains to be determined. This review mainly focuses on the molecular basis of smooth muscle myosin heavy chain isoform diversity, its expression during development and disease, and its role in muscle physiology.

    Microscopy research and technique 2000;50;6;532-40

  • Myosin heavy chain gene expression in normal and hyperplastic human prostate tissue.

    Lin VK, Wang D, Lee IL, Vasquez D, Fagelson JE and McConnell JD

    Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9110, USA. victor.lin@email.swmed.edu

    Background: Benign prostatic hyperplasia (BPH) is common among aging men. Over 80% of males 50-60 years and older have various degrees of bladder outlet obstruction secondary to BPH. Despite the tremendous medical impact of BPH, its molecular pathophysiology remains unclear. Current BPH research focuses on steroid hormonal effects, stromal-epithelial cell interaction, and oncogenes and growth factors. But little is known about the potential prostatic smooth muscle (SM) alterations that may occur during stromal hyperplasia.

    Methods: To study SM phenotypic modulation in hyperplastic prostatic growth, we isolated and characterized the 3' end of human SM myosin heavy chain (SMMHC) cDNA as a molecular probe. Expression of SMMHC and nonmuscle myosin heavy chain (NMMHC) in human prostates was analyzed using Western blot, Northern blot, and in situ hybridization to determine if BPH tissue expresses significantly less SMMHC and more NMMHC than a normal prostate. In addition, a competitive, reverse transcription (RT) polymerase chain reaction (PCR) method was adapted to quantify SMMHC and NMMHC mRNA expression at the sensitivity level of 10(-21) mole per mg of wet tissue.

    Results: Western blot, Northern blot, and in situ hybridization results reveal that both SMMHC and NMMHC are expressed in the human prostate, while SMMHC is the predominant form found in normal prostate stroma. Results from competitive RT-PCR analysis indicate that NMMHC mRNA expression is approximately 10(-20) mole/mg of tissue. The SMMHC mRNA expressed is approximately 10(-18) mole/mg. No significant difference was found when NMMHC mRNA expression was compared between normal and BPH periurethral tissues. However, SMMHC expression was reduced almost fivefold in BPH compared to normal prostate, despite an increase in prostatic stromal mass.

    Conclusions: Our results suggest the pathogenesis of BPH is associated with a unique type of SM proliferation. Such proliferation is characterized by downregulation of SMMHC mRNA expression but without upregulation of NMMHC mRNA expression, the pattern seen in proliferating SM cells in culture and in other pathologic forms of SM hyperplasia (e.g., atherosclerosis). These findings support a model of BPH typified by active smooth muscle proliferation early in the disease process, and supports clinical observations that suggest ongoing prostate growth of the prostate is minimal in older men. Therapeutic strategies to prevent disease progression should therefore focus on early phases of prostatic growth.

    Funded by: NIDDK NIH HHS: DK47657

    The Prostate 2000;44;3;193-203

  • Intracoronary serum smooth muscle myosin heavy chain levels following PTCA may predict restenosis.

    Tsuchio Y, Naito S, Nogami A, Hoshizaki H, Oshima S, Taniguchi K, Katoh H, Suzuki T, Kurabayashi M, Hasegawa A and Nagai R

    Cardiology Division, Gunma Prefectural Cardiovascular Center, Maebashi, Japan.

    Recently a novel biochemical method that uses an immunoassay to quantitate serum smooth muscle myosin heavy chain (SMMHC) levels was developed for diagnosis of aortic dissection.) The purpose of this study was to determine whether SMMHC released from the coronary arterial wall can be used to predict restenosis after percutaneous transluminal coronary angioplasty (PTCA). Fifty-two consecutive patients undergoing successful PTCA for single vessel disease were examined (40 men, 12 women, 63 +/- 8 years). Intracoronary blood samples were obtained distal to the lesion, and from the femoral artery after PTCA. In 10 patients, blood samples were taken immediately after the final balloon inflation, and 10 and 20 minutes after PTCA. SMMHC levels were measured by ELISA using SMMHC-specific monoclonal antibodies. Follow-up coronary angiography was performed 3 months after PTCA. Intracoronary serum SMMHC levels were significantly higher than those obtained from the femoral artery (10.6 +/- 1.5 vs 2.1 +/- 0.1 ng / ml, p < or = 0.001). Of 40 patients without apparent dissection, the 23 patients who did not develop restenosis in the follow-up study were found to have had higher levels of intracoronary SMMHC levels immediately after PTCA compared to the 17 patients with restenosis (15.2 +/- 2.9 vs 7.1 +/- 1.2 ng /ml, p < or = 0.05). We suggest that elevated intracoronary SMMHC levels after PTCA may reflect the extent of injury to the arterial wall. Intracoronary SMMHC may be a possible biochemical marker for the prediction of restenosis.

    Japanese heart journal 2000;41;2;131-40

  • Genome duplications and other features in 12 Mb of DNA sequence from human chromosome 16p and 16q.

    Loftus BJ, Kim UJ, Sneddon VP, Kalush F, Brandon R, Fuhrmann J, Mason T, Crosby ML, Barnstead M, Cronin L, Deslattes Mays A, Cao Y, Xu RX, Kang HL, Mitchell S, Eichler EE, Harris PC, Venter JC and Adams MD

    The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, Maryland 20850, USA.

    Several publicly funded large-scale sequencing efforts have been initiated with the goal of completing the first reference human genome sequence by the year 2005. Here we present the results of analysis of 11.8 Mb of genomic sequence from chromosome 16. The apparent gene density varies throughout the region, but the number of genes predicted (84) suggests that this is a gene-poor region. This result may also suggest that the total number of human genes is likely to be at the lower end of published estimates. One of the most interesting aspects of this region of the genome is the presence of highly homologous, recently duplicated tracts of sequence distributed throughout the p-arm. Such duplications have implications for mapping and gene analysis as well as the predisposition to recurrent chromosomal structural rearrangements associated with genetic disease.

    Funded by: NHGRI NIH HHS: R01-HG01464

    Genomics 1999;60;3;295-308

  • Prediction of the coding sequences of unidentified human genes. XII. The complete sequences of 100 new cDNA clones from brain which code for large proteins in vitro.

    Nagase T, Ishikawa K, Suyama M, Kikuno R, Hirosawa M, Miyajima N, Tanaka A, Kotani H, Nomura N and Ohara O

    Kazusa DNA Research Institute, Kisarazu, Chiba, Japan.

    In this paper, we report the sequences of 100 cDNA clones newly determined from a set of size-fractionated human brain cDNA libraries and predict the coding sequences of the corresponding genes, named KIAA0819 to KIAA0918. These cDNA clones were selected on the basis of their coding potentials of large proteins (50 kDa and more) by using in vitro transcription/translation assays. The sequence data showed that the average sizes of the inserts and corresponding open reading frames are 4.4 kb and 2.5 kb (831 amino acid residues), respectively. Homology and motif/domain searches against the public databases indicated that the predicted coding sequences of 83 genes were similar to those of known genes, 59% of which (49 genes) were categorized as coding for proteins functionally related to cell signaling/communication, cell structure/motility and nucleic acid management. The chromosomal locations and the expression profiles of all the genes were also examined. For 54 clones including brain-specific ones, the mRNA levels were further examined among 8 brain regions (amygdala, corpus callosum, cerebellum, caudate nucleus, hippocampus, substantia nigra, subthalamic nucleus, and thalamus), spinal cord, and fetal brain.

    DNA research : an international journal for rapid publication of reports on genes and genomes 1998;5;6;355-64

  • The chimeric protein, PEBP2 beta/CBF beta-SMMHC, disorganizes cytoplasmic stress fibers and inhibits transcriptional activation.

    Tanaka Y, Fujii M, Hayashi K, Chiba N, Akaishi T, Shineha R, Nishihira T, Satomi S, Ito Y, Watanabe T and Satake M

    Department of Molecular Immunology, Institute of Development, Aging and Cancer, Sendai, Japan.

    The chromosomal inversion 16(p13;q22) associated with human acute myeloid leukemia generates the chimeric PEBP2 beta/CBF beta-SMMHC gene. The PEBP2 beta/CBF beta portion of the chimeric polypeptide harbors most of the amino acid sequence of the PEBP2 beta/CBF beta protein, the non-DNA binding subunit of the heterodimeric transcription factor, PEBP2/CBF, whereas the SMMHC portion of the chimera consists of the rod domain of the smooth muscle myosin heavy chain molecule. In this study we examined the subcellular localization of the chimeric protein and its effect both on stress fibers and transcriptional activation by transfecting cDNA into tissue culture cells. The localization of the chimera was investigated by immunocytochemical staining of cells and was found to be both cytoplasmic and nuclear. One aspect of the effect of expression of the chimera was a drastic alteration of cell morphology. The cells appeared elongated and possessed long cytoplasmic processes. Double fluorescent labeling revealed disorganization of the stress fibers and an altered F-actin staining pattern in the transfected cells. Studies using a deletion mutant showed that both the PEBP2 beta/CBF beta and SMMHC domains are necessary for the induction of the morphological alteration. A significant proportion of the chimeric protein was retained in the cytoskeleton after detergent extraction of the cells and could be recuperated as a membrane fraction, suggesting that this is one of the probable sites of action of the PEBP2 beta/CBF beta-SMMHC protein. Another effect of the chimeric protein was inhibition of transcriptional activation dependent on the PEBP2/CBF binding DNA sequence. However, deregulation of PEBP2/CBF site dependent transcription by itself was not sufficient to induce cell morphological changes. Taken together, these results indicate that the PEBP2 beta/CBF beta-SMMHC chimeric protein acts at two levels, at the level of stress fiber organization and at the level of transcriptional activation. We suggest that the action of PEBP2 beta/CBF beta-SMMHC depends to a great extent on whether it is located in the cytoplasm or in the nucleus.

    Oncogene 1998;17;6;699-708

  • PRAK, a novel protein kinase regulated by the p38 MAP kinase.

    New L, Jiang Y, Zhao M, Liu K, Zhu W, Flood LJ, Kato Y, Parry GC and Han J

    Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA.

    We have identified and cloned a novel serine/ threonine kinase, p38-regulated/activated protein kinase (PRAK). PRAK is a 471 amino acid protein with 20-30% sequence identity to the known MAP kinase-regulated protein kinases RSK1/2/3, MNK1/2 and MAPKAP-K2/3. PRAK was found to be expressed in all human tissues and cell lines examined. In HeLa cells, PRAK was activated in response to cellular stress and proinflammatory cytokines. PRAK activity was regulated by p38alpha and p38beta both in vitro and in vivo and Thr182 was shown to be the regulatory phosphorylation site. Activated PRAK in turn phosphorylated small heat shock protein 27 (HSP27) at the physiologically relevant sites. An in-gel kinase assay demonstrated that PRAK is a major stress-activated kinase that can phosphorylate small heat shock protein, suggesting a potential role for PRAK in mediating stress-induced HSP27 phosphorylation in vivo.

    Funded by: NIAID NIH HHS: AI41637; NIGMS NIH HHS: GM51417

    The EMBO journal 1998;17;12;3372-84

  • Human smooth muscle myosin heavy chain isoforms as molecular markers for vascular development and atherosclerosis.

    Aikawa M, Sivam PN, Kuro-o M, Kimura K, Nakahara K, Takewaki S, Ueda M, Yamaguchi H, Yazaki Y, Periasamy M et al.

    Third Department of Internal Medicine, University of Tokyo, Japan.

    Smooth muscle myosin heavy chains (MHCs) exist in multiple isoforms. Rabbit smooth muscles contain at least three types of MHC isoforms: SM1 (204 kD), SM2 (200 kD), and SMemb (200 kD). SM1 and SM2 are specific to smooth muscles, but SMemb is a nonmuscle-type MHC abundantly expressed in the embryonic aorta. We recently reported that these three MHC isoforms are differentially expressed in rabbit during normal vascular development and in experimental arteriosclerosis and atherosclerosis. The purpose of this study was to clarify whether expression of human smooth muscle MHC isoforms is regulated in developing arteries and in atherosclerotic lesions. To accomplish this, we have isolated and characterized three cDNA clones from human smooth muscle: SMHC94 (SM1), SMHC93 (SM2), and HSME6 (SMemb). The expression of SM2 mRNA in the fetal aorta was significantly lower as compared with SM1 mRNA, but the ratio of SM2 to SM1 mRNA was increased after birth. SMemb mRNA in the aorta was decreased after birth but appeared to be increased in the aged. To further examine the MHC expression at the histological level, we have developed three antibodies against human SM1, SM2, and SMemb using the isoform-specific sequences of the carboxyl terminal end. Immunohistologically, SM1 was constitutively positive from the fetal stage to adulthood in the apparently normal media of the aorta and coronary arteries, whereas SM2 was negative in fetal arteries of the early gestational stage. In human, unlike rabbit, aorta or coronary arteries, SMemb was detected even in the adult. However, smaller-sized arteries, like the vasa vasorum of the aorta or intramyocardial coronary arterioles, were negative for SMemb. Diffuse intimal thickening in the major coronary arteries was found to be composed of smooth muscles, reacting equally to three antibodies for MHC isoforms, but reactivities with anti-SM2 antibody were reduced with aging. With progression of atherosclerosis, intimal smooth muscles diminished the expression of not only SM2 but also SM1, whereas alpha-smooth muscle actin was well preserved. We conclude from these results that smooth muscle MHC isoforms are important molecular markers for studying human vascular smooth muscle cell differentiation as well as the cellular mechanisms of atherosclerosis.

    Funded by: NHLBI NIH HHS: R01 HL-38355-06

    Circulation research 1993;73;6;1000-12

  • A gene for a myosin peptide is disrupted by the inv(16)(p13q22) in acute nonlymphocytic leukemia M4Eo.

    van der Reijden BA, Dauwerse JG, Wessels JW, Beverstock GC, Hagemeijer A, van Ommen GJ and Breuning MH

    Department of Human Genetics, Leiden University, The Netherlands.

    Chromosome 16 aberrations are well known in acute nonlymphocytic leukemia (ANLL). The most frequent chromosome 16 aberration in ANLL subtype M4Eo is the inv(16)(p13q22). Recently, we showed that in 5 inv(16) patients with ANLL M4Eo the short arm breakpoints are clustered within a 14-kb genomic EcoRI fragment. We report here the identification of a gene situated in the 14-kb fragment. The gene, which codes for a myosin peptide, is disrupted by the inversion of chromosome 16 in the 5 patients. To the best of our knowledge, this is the first report of a myosin gene disrupted in leukemia.

    Blood 1993;82;10;2948-52

  • Smooth muscle myosin heavy chain locus (MYH11) maps to 16p13.13-p13.12 and establishes a new region of conserved synteny between human 16p and mouse 16.

    Deng Z, Liu P, Marlton P, Claxton DF, Lane S, Callen DF, Collins FS and Siciliano MJ

    Department of Molecular Genetics, University of Texas M.D. Anderson Cancer Center, Houston 77030.

    The human smooth muscle myosin heavy chain locus (MYH11) was mapped by fluorescence in situ hybridization to the middle of the p arm of chromosome 16 using a genomic cosmid clone containing coding sequences of the gene as probe. Probe from coding sequence, when applied to Southern blots of a panel of hybrids containing different portions of human chromosome 16, localized the gene to 16p13.13-13.12. Coding sequence PCR primers, when used on the DNA from a CHO-mouse hybrid clone mapping panel informative for mouse chromosomes, showed that the gene was located on mouse chromosome 16. These results correct a recent assignment of MYH11 from 16q12.2 to the region of the 16p-arm inversion breakpoint seen in acute myelomonocytic leukemia (AMML) M4Eo and demonstrate that the conflicting data do not result from the presence of additional MYH genes on the q arm of the chromosome. Also, a new region of conserved synteny between human 16p and mouse 16 is established.

    Funded by: NCI NIH HHS: CA65164

    Genomics 1993;18;1;156-9

  • Human smooth muscle myosin heavy chain gene mapped to chromosomal region 16q12.

    Matsuoka R, Yoshida MC, Furutani Y, Imamura S, Kanda N, Yanagisawa M, Masaki T and Takao A

    Department of Pediatric Cardiology, Heart Institute of Japan, Tokyo.

    The partial nucleotide sequence encoding the rod portion of the entire amino acid sequence of human smooth muscle myosin heavy chain (MHC) which corresponds to MYH11, according to Human Gene Mapping nomenclature, has been determined by cloning a complementary DNA (cDNA) and sequencing the cDNA (UMYHSM). Northern blot analysis with the UMYHSM fragment (4.3 Kb) showed that the smooth muscle MHC of the human umbilical artery is expressed in the human umbilical artery, bladder, esophagus and trachea. Southern blot analysis of human genomic DNA from human-mouse or human-Chinese hamster somatic cell hybrids demonstrated that the human smooth muscle MHC was mapped to human chromosome 16. Regional mapping of UMYHSM was performed using human cell lines with partial deletion and trisomy of chromosome 16. As a result, the human smooth muscle MHC gene segregated with 16p11-q12. In situ hybridization of biotin-labeled human smooth muscle MHC probe (UMYHSM fragment) to normal human metaphase chromosome independently showed that the human smooth muscle MHC gene (MYH11) is assigned to chromosome region 16q12. Analysis of early metaphase chromosomes showed that hybridization signals were in 16q12.1. In the human, although skeletal, cardiac, smooth muscle, and nonmuscle MHC genes are mapped to chromosomes 17, 14, 16, and 22, respectively, structural similarities of these MHC genes strongly suggest the common origin of these genes.

    American journal of medical genetics 1993;46;1;61-7

  • Cleavage of human and mouse cytoskeletal and sarcomeric proteins by human immunodeficiency virus type 1 protease. Actin, desmin, myosin, and tropomyosin.

    Shoeman RL, Sachse C, Höner B, Mothes E, Kaufmann M and Traub P

    Max-Planck-Institut für Zellbiologie, Ladenburg, Federal Republic of Germany.

    HeLa cell actin was cleaved by human immunodeficiency virus type 1 protease when in its soluble, globular form (G-actin). No cleavage of the polymerized, filamentous form of actin (F-actin) was observed when examined by denaturing gel electrophoresis; however, electron microscopy revealed a low level of cleavage of F-actin. Immunoblotting of mouse skeletal and human pectoral muscle myofibrils treated in vitro with human immunodeficiency virus type 1 protease showed that myosin heavy chain, desmin, tropomyosin, and a fraction of the actin were all cleaved. Electron microscopy of these myofibrils demonstrated changes consistent with cleavage of these proteins: Z-lines were rapidly lost, the length of the A bands was shortened, and the thick filaments (myosin filaments) were often laterally frayed such that the structures disintegrated. Nonmuscle myosin heavy chains were also cleaved by this enzyme in vitro. These data demonstrate that this protease can cause alterations in muscle cell ultrastructure in vitro that may be of clinical relevance in infected individuals.

    The American journal of pathology 1993;142;1;221-30

Gene lists (7)

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
L00000015 G2C Homo sapiens Human NRC Human orthologues of mouse NRC adapted from Collins et al (2006) 186
L00000016 G2C Homo sapiens Human PSP Human orthologues of mouse PSP adapted from Collins et al (2006) 1121
L00000059 G2C Homo sapiens BAYES-COLLINS-HUMAN-PSD-CONSENSUS Human cortex PSD consensus 748
L00000061 G2C Homo sapiens BAYES-COLLINS-MOUSE-PSD-CONSENSUS Mouse cortex PSD consensus (ortho) 984
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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