E-MTAB-1363 - MicroRNA profiling by array of normal bone marrow plasma cells, malignant plasma cells from patients with monoclonal gammopathy of unknown significance (MGUS) or multiple myeloma, and myeloma cell line samples
Released on 9 January 2014, last updated on 3 May 2014
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.
microRNA profiling by array, cell type comparison, co-expression, in vitro