Expression analyses identify MLL as a prominent target of 11q23 amplification and support an etiologic role for MLL gain of function in myeloid malign
From the Center for Medical Genetics, University Hospital Ghent, Belgium; Laboratory for Leukemia Diagnostics, University Hospital Grosshadern, Ludwig-Maximilians-University of Munich, München, Germany; Department of Molecular Medicine, Karolinska Hospital and Institute, Stockholm, Sweden; Division of Hematology and Oncology, Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Ohio State University, Columbus; Departments of Clinical Genetics/Cell Biology and Genetics, Erasmus MC, Rotterdam, The Netherlands; Department of Hematology and Center for Human Genetics, Cliniques Universitaires Saint-Luc, Brussels, Belgium; Department of Human Genetics, CHU Sart Tilman, Liège, Belgium; Laboratoire d'Hématologie, CHU Toulouse, France; Centre for Human Genetics, University of Leuven, Belgium.l)yn$, 百拇医药
MLL amplification was recently recognized as a recurrent aberration in acute myeloid leukemia (AML) and myelodys-plastic syndrome (MDS), associated with adverse prognosis and karyotype complexity. Here we present detailed results of fluorescence in situ hybridization (FISH) and expression analyses of MLL and 5 selected 11q candidate oncogenes (CBL, DDX6, ETS1, FLI1, and PLZF) in 31 patient samples and one cell line with 11q23 gain. FISH analyses revealed that the 11q23 amplicon invariably encompassed MLL, DDX6, ETS1, and FLI1, whereas expression analyses identified MLL and DDX6 as the most differentially expressed genes among samples with and without 11q23 copy gain or amplification. In MLL-amplified samples, a significant transcriptional up-regulation of MEIS1, PROML1, ADAM10, NKG2D, and ITPA was noted. Further analyses, designed to elucidate a possible role of the 11q overexpressed genes (MLL, DDX6, FLI1, and ETS1) in unselected MDS and AML samples, revealed a significant upregulation of MLL in MDS. Our findings confirm the MLL gene as a prominent target of 11q23 amplification and provide further evidence for an etiologic role for MLL gain of function in myeloid malignancies. In addition, our results indicate that the transcriptional program associated with MLL rearrangements and MLL overexpression displays significant similarities.(Bruce Poppe Jo Vandesompele Claudia Schoch, Charlotta Lindvall Krzysztof Mrózek Clara D. Bloomfield)
MLL amplification was recently recognized as a recurrent aberration in acute myeloid leukemia (AML) and myelodys-plastic syndrome (MDS), associated with adverse prognosis and karyotype complexity. Here we present detailed results of fluorescence in situ hybridization (FISH) and expression analyses of MLL and 5 selected 11q candidate oncogenes (CBL, DDX6, ETS1, FLI1, and PLZF) in 31 patient samples and one cell line with 11q23 gain. FISH analyses revealed that the 11q23 amplicon invariably encompassed MLL, DDX6, ETS1, and FLI1, whereas expression analyses identified MLL and DDX6 as the most differentially expressed genes among samples with and without 11q23 copy gain or amplification. In MLL-amplified samples, a significant transcriptional up-regulation of MEIS1, PROML1, ADAM10, NKG2D, and ITPA was noted. Further analyses, designed to elucidate a possible role of the 11q overexpressed genes (MLL, DDX6, FLI1, and ETS1) in unselected MDS and AML samples, revealed a significant upregulation of MLL in MDS. Our findings confirm the MLL gene as a prominent target of 11q23 amplification and provide further evidence for an etiologic role for MLL gain of function in myeloid malignancies. In addition, our results indicate that the transcriptional program associated with MLL rearrangements and MLL overexpression displays significant similarities.(Bruce Poppe Jo Vandesompele Claudia Schoch, Charlotta Lindvall Krzysztof Mrózek Clara D. Bloomfield)