Project description:We used microarray analyses of patient myeloma cells (n=52) to correlate individual miRNA expression profiles with GEP-based risk defined by mRNA expression profilesx as well as clinical features of the disease. Unlike for mRNAs, genome-wide elevation of miRNA expression patterns were significantly positively associated with a mRNA-based GEP-risk score (P <.01) and proliferation index (P <.05). Consistent with our observation of global deregulation of miRNA expression profiles, silencing EIF2C2/AGO2, a gene component of the mRNA-based high-risk signature and a master regulator of the genesis and functionality of all miRNAs, dramatically decreased viability in myeloma cell lines. mRNA expression profiling: We performed protein-coding gene expression profiles of myeloma cells from newly diagnosed patients with different molecularly defined disease types. miRNA expression profiling: We used microarray analyses of patient myeloma cells (n=52) to correlate individual miRNA expression profiles with GEP-based risk defined by mRNA expression profiles as well as clinical features of the disease.
Project description:In order to identify relevant, molecularly defined subgroups in Multiple Myeloma (MM), gene expression profiling (GEP) was performed on purified CD138+ plasma cells of 320 newly diagnosed myeloma patients included in the Dutch-Belgian/German HOVON-65/ GMMG-HD4 trial using Affymetrix Gene Chip U133 plus 2.0 arrays. Hierarchical clustering identified 10 distinct subgroups. Bone marrow plasma cell samples were obtained from 320 newly diagnosed multiple myeloma patients included in a large multicenter, prospective, randomized phase III trial (HOVON65/GMMG-HD4). Purified myeloma plasma cells samples with a monoclonal plasma cell purity > 80% were used for analysis.
Project description:miRNA profiling in multiple myeloma - microRNAs represent a class of noncoding regulators of gene expression implicated in several biological and pathophysiological processes, including cancer. We investigate here their role in multiple myeloma using miChip-arrays interrogating 559 miRNAs in 92 purified myeloma-, MGUS-, normal plasma cell- and myeloma cell line samples. Impact on gene expression is assessed by Affymetrix U133 2.0 DNA-microarrays in 741 samples including two cohorts of 332 and 345 myeloma patients; chromosomal aberrations are assessed by iFISH, survival for 247 and 345 patients undergoing up-front high-dose therapy and autologous stem cell transplantation. Compared to normal plasma cells, 67/559 (12%) miRNAs are differentially expressed with fold changes of 4.6 to -3.1 in myeloma-, 20 (3.6%) in MGUS-samples, and three (0.5%) between MGUS- and myeloma-samples. Expression of miRNAs is associated with biological and pathophysiological parameters, i.e. proliferation, chromosomal aberrations, e.g. t(4;14), tumor mass, and gene expression-based high-risk scores. This holds true for target-gene signatures of regulated mRNAs. miRNA-expression confers prognostic significance for event-free (72/559) and overall survival (69/559), as do respective target-gene signatures. In conclusion, the miRNome of myeloma confers a pattern of small changes of individual miRNAs compared to normal plasma cells impacting on gene expression, biological functions, and survival.
Project description:Gene expression profiling of CD138 purified bone marrow plasma cells of normal donnors, previoulsy untreated MGUS and multiple myeloma patients, and myeloma cell lines
Project description:Multiple myeloma (MM), also known as plasma cell myeloma, is a cancer of plasma cells, a type of white blood cell normally responsible for producing antibodies. There is no cure for MM. In addition, the mechanism underlying abnormal production of plasma cells is not clear. In this experiment, peripheral blood was obtained from normal healthy donors and multiple myeloma (MM) patients. Peripheral blood mononuclear cells (PBMC) were separated by Ficoll separation solution. Samples of four donors were pooled and Samples of four MM patients were pooled. The aim was to characterize the mRNA profile of MM patients compared to healthy donors and find the new target of diagnosis or treatment for MM.
