Project description:Primary plasma cell leukemia (pPCL) is a rare and very aggressive form of plasma cell dyscrasias. To date, no information of microRNA expression in pPCL has been reported. To investigate the role of miRNAs in pPCL, we analyzed global miRNA expression profiles of highly purified malignant plasma cells from 18 previously untreated patients included in a prospective clinical trial. MiRNA expression patterns were evaluated in the context of the molecular abnormalities of the disease and in comparison with a representative cohort of multiple myeloma (MM) patients. We identified a series of deregulated miRNAs in pPCL (42 up-regulated and 41 down-regulated) which may have a putative role in contributing to tumor progression in MM. Furthermore, we integrated miRNA and gene expression data with computational prediction of miRNA targets, finding that miRNAs differentially expressed between MM and pPCL could regulate genes with important functions in cancer. Overall, our study represents the first attempt to investigate the involvement of miRNAs in pPCL and may contribute to develop functional approaches to investigate the activity of deregulated miRNAs in aggressive forms of plasma cell dyscarsias and their possible role as novel therapeutic targets.
Project description:Multiple myeloma (MM) and its premalignant precursor MGUS (monoclonal gammopathy of undetermined significance) are clonal plasma cell diseases that develop in the bone marrow (BM) and are dependent on microenvironmental interactions. Primary bone marrow stromal cells (BMSCs) are key players in the BM microenvironment, however, their role in MGUS/MM pathophysiology is not known. We therefore investigated potential disease-specific alterations in prospectively isolated BMSCs from MM, MGUS and healthy controls. Clear disease-related BMSC surface marker and gene expression differences were recorded, and deep sequencing identified shared MGUS/MM as well as MM-specific molecular signatures. Moreover, we identified genes that were deregulated in a disease-stage manner, thus reflecting the progression from normal to MGUS and MM. Analysis of primary BMSCs revealed disease-stage related protein and gene expression patterns, which provides novel insight into the stromal transitions and their functional implications for plasma cell disease development and progression.
Project description:In multiple myeloma (MM), endothelial progenitor cells (EPCs) regulate tumor angiogenesis and disease progression. They share a common bone marrow microenvironment with myeloma tumor cells. CD138+ tumor plasma cells from 12 newly diagnosed patients with advanced MM were examined for genomic instability by RNA microarrays to assess changes in gene expression.
Project description:In multiple myeloma (MM), endothelial progenitor cells (EPCs) regulate tumor angiogenesis and disease progression. They share a common bone marrow microenvironment with myeloma tumor cells. CD138+ tumor plasma cells from 12 newly diagnosed patients with advanced MM were examined for genomic instability by RNA microarrays to assess changes in gene expression. Tumor cells were derived from single-cell suspensions of bone marrow (BM) aspirates from newly diagnosed MM patients, and RNA was extracted for microarray hybridization.
Project description:Primary plasma cell leukemia (pPCL) is a rare and very aggressive form of plasma cell dyscrasias. To date, no information of microRNA expression in pPCL has been reported. To investigate the role of miRNAs in pPCL, we analyzed global miRNA expression profiles of highly purified malignant plasma cells from 18 previously untreated patients included in a prospective clinical trial. MiRNA expression patterns were evaluated in the context of the molecular abnormalities of the disease and in comparison with a representative cohort of multiple myeloma (MM) patients. We identified a series of deregulated miRNAs in pPCL (42 up-regulated and 41 down-regulated) which may have a putative role in contributing to tumor progression in MM. Furthermore, we integrated miRNA and gene expression data with computational prediction of miRNA targets, finding that miRNAs differentially expressed between MM and pPCL could regulate genes with important functions in cancer. Overall, our study represents the first attempt to investigate the involvement of miRNAs in pPCL and may contribute to develop functional approaches to investigate the activity of deregulated miRNAs in aggressive forms of plasma cell dyscarsias and their possible role as novel therapeutic targets. This series of microarray experiments contains the microRNA profiles of purified plasma cells (PCs) obtained from 39 multiple myeloma (MM) and 18 primary plasma cell leukemia (pPCL) at diagnosis. PCs were purified from bone marrow specimens, after red blood cell lysis with 0.86% ammonium chloride, using CD138 immunomagnetic microbeads. The purity of the positively selected PCs was assessed by morphology and flow cytometry and was > 90% in all cases. 500 nanograms of total RNA was processed in accordance with the manufacturer's protocols (Agilent Technologies) to generate Cy3-labelled RNA, which were purified on chromatography columns (Micro Biospin 6, Bio-Rad, Hercules, CA) and then hybridized on an Agilent microarray (G4470B) at 55M-BM-!C for 17 hr in a rotating oven. Images at 5 um resolution were generated using an Agilent scanner G2505B. The Feature Extraction 10.7.3.1 software (Agilent Technologies) was used to obtain the microarray raw-data. The raw gTotalGeneSignal has been recalculated using the procedures described in Agilent Feature Extraction Software version 10.1 manual. Non-human probes, miRNAs flagged as M-CM-^RabsentM-CM-^S (i.e. expressed below background levels) throughout the whole dataset and miRNAs expired according to Sanger miRBase Release 15 (April 2010) were discarded, and a quantile normalization was applied on raw data using the aroma.light package for Bioconducor. The data were then converted to obtain positive values throughout the dataset, at a minimum value of 1, and log2 transformed.
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:Multiple myeloma is a plasma cell malignancy of the bone marrow. Despite therapeutic advances in multiple myeloma, it remains incurable and better risk stratification as well as new therapies are therefore highly needed. While genetics and gene expression have been extensively studied leading to new insights in disease biology and improved prognostic models, the proteome of multiple myeloma has not been systematically assessed. Here, we provide a comprehensive multi-omic analysis including deep tandem mass tags (TMT)-based quantitative global (phospho)proteomics, RNA sequencing and nanopore DNA sequencing of 138 primary patient-derived plasma cell malignancy samples, including treatment-naive multiple myeloma cases selected for clinical trials, plasma cell leukemia, and the premalignancy MGUS, as well as healthy controls. We found that the (phospho)proteome of malignant plasma cells is highly deregulated as compared to healthy cells and is both defined by chromosomal alterations and extensive post-transcriptional regulation. A protein signature consisting of 8 proteins was identified that is associated with aggressive disease and highly predictive for outcomes in newly diagnosed multiple myeloma. Integration with functional genetics and single-cell sequencing revealed generally and genetic subtype-specific deregulated proteins and pathways in plasma cell malignancies that include novel potential targets for (immuno)therapies. Our study provides a unique resource for investigating biology and new therapeutic approaches in multiple myeloma and associated diseases and highlights the broad implications of proteomic studies in cancer.
Project description:The historical lack of pre-clinical models reflecting the genetic heterogeneity of multiple myeloma (MM) hampers advancing therapeutic discoveries. To circumvent this limitation, we have generated fifteen genetically diverse models that developed bone marrow tumors fulfilling MM pathogenesis. Transcriptomic analysis of tumor plasma cells revealed that MYC activation regulates time to progression. Bone marrow cell composition analysis classified myeloma tumors into immune-cold and inflamed categories, which condition immune checkpoint blockade responses in mouse multiple myeloma models.
Project description:Bone marrow (BM) niches provide an optimal substrate for multiple myeloma (MM) cell lodgement and growth. Nevertheless, little is known about the putative mechanisms by which the BM microenvironment can lead to initiation or progression of oncogenesis in this disease. We have demonstrated that BM mesenchymal stromal cell-derived exosomes transfer their miRNA and protein content to clonal plasma cells, thus acting as synaptic vesicles responsible for molding the microenvironment surrounding multiple myeloma (MM) cells, leading to MM growth, dissemination and, therefore, disease progression. We used microarray to detail the changes in microRNA expression in MM-BM mesenchymal stromal cell (MSC)-derived exosomes, compared to normal- and monoclonal gammopathy of undetermined significance- BM-MSC-derived exosomes. Exosomes have been isolated from cell culture supernatant of BM-MSCs (MM=7; MGUS=2; Normal=4), and subsequently evaluated at ultrastructural level by using electron microscopy and immunogolf labeling. RNA was extracted; and miRNA profiling has been assessed by using TaqMan human miRNA profiling. Mean miRNA expression value has been used for miRNA RT-qPCR data normalization, as described (Mestdagh et al., 2009).
Project description:In multiple myeloma (MM), endothelial progenitor cells (EPCs) regulate tumor angiogenesis and disease progression. EPCs from 16 newly diagnosed patients with advanced MM were examined for genomic instability by aCGH to assess chromosomal gains and losses. Data were compared to aCGH results from corresponding CD138+ tumor plasma cells from these patients.