Project description:To further investigate the differential expression miRNA of multiple myeloma, three multiple myeloma samples and three normal samples were used for miRNA sequencing.
Project description:The MMSET (Multiple Myeloma SET domain) protein is overexpressed in multiple myeloma patients with the translocation t(4;14). Although studies have shown the involvement of MMSET/WHSC1 in development, its mode of action in the pathogenesis of multiple myeloma (MM) is largely unknown. We found that MMSET is a major regulator of chromatin structure and transcription in t(4;14) MM cells. High levels of MMSET correlate with an increase in lysine 36 methylation of histone H3 and a decrease in lysine 27 methylation across the genome, leading to a more open structural state of the chromatin. Loss of MMSET expression alters adhesion properties, suppresses growth and induces apoptosis in MM cells. Consequently, genes affected by high levels of MMSET are implicated in the p53 pathway, cell cycle regulation and integrin signaling. Regulation of many of these genes required functional histone methyl-transferase (HMT) activity of MMSET. These results implicate MMSET as a major epigenetic regulator in t(4;14)+ MM.
Project description:The MMSET (Multiple Myeloma SET domain) protein is overexpressed in multiple myeloma patients with the translocation t(4;14). Although studies have shown the involvement of MMSET/WHSC1 in development, its mode of action in the pathogenesis of multiple myeloma (MM) is largely unknown. We found that MMSET is a major regulator of chromatin structure and transcription in t(4;14) MM cells. High levels of MMSET correlate with an increase in lysine 36 methylation of histone H3 and a decrease in lysine 27 methylation across the genome, leading to a more open structural state of the chromatin. Loss of MMSET expression alters adhesion properties, suppresses growth and induces apoptosis in MM cells. Consequently, genes affected by high levels of MMSET are implicated in the p53 pathway, cell cycle regulation and integrin signaling. Regulation of many of these genes required functional histone methyl-transferase (HMT) activity of MMSET. These results implicate MMSET as a major epigenetic regulator in t(4;14)+ MM. Total RNA was isolated from two different systems: an inducible knock down designed in the 5' region of MMSET. Upon addition of doxycycline we block MMSET expression. The second system we used was a repletion system. By retroviral infection of knock out cells for MMSET we restored the expression of MMSET wild type and two mutants of the protein: one active and one catalytically inactive. Triplicates of each sample were analyzed.
Project description:Multiple myeloma (MM) is a hematopoietic malignancy. Based on its laboratory and clinical presentation, it can be categorized as MGUS, smoldering myeloma, and multiple myeloma. Previous studies have indicated that the expression levels of miRNAs differ across various stages of the disease, and exosomes are involved in modulating the progression and metastasis of cancers through miRNAs. This study aims to analyze the expression levels of miRNAs in the serum exosomes of healthy individuals and those with myeloma bone marrow.
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:1) We identified the genes whose expression was up- and down-regulated by the adhesion to bone marrow stromal cells in human multiple myeloma cell line RPMI8226. 2) We identified the genes whose expression was up- and down-regulated by the PI3K inhibitor PF-04691502 in human multiple myeloma cell line RPMI8226. We isolated mRNA from the multiple myeloma cell line RPMI8226 under drug-resistant conditions, and subjected them to gene expression profiling using an Agilent GeneChip Array.