Project description:Molecular pathways activated in MALT lymphoma are not well defined. In this study, we perform gene expression profiling on 35 pulmonary MALT lymphoma using fresh frozen biopsy samples Keywords: Cell type analysis and disease state analysis
Project description:Molecular pathways activated in MALT lymphoma are not well defined. In this study, we perform gene expression profiling on 35 pulmonary MALT lymphoma using fresh frozen biopsy samples Experiment Overall Design: Total RNA was extracted from fresh frozen tisues of 35 newly diagnosed Pulmonary MALT, as defined by WHO classification, and hybridized to Affymetrix U133plus2 chip. Gene expression profile from other B and T cell malignancies and normal cellular and tissue counterpart were obtained from published dataset for comparison.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Comparison of gene expression profiling analysis of bone marrow isolated CD34+ cells from patients with MALT lymphoma vs. healthy individuals revealed a large number of differentially expressed genes that included NF-kB target genes, genes involved in inflamatory signalling and immunoglobulin genes, suggesting an early lymphoid B-cell priming. Chromosomal translocations involving MALT1 gene are hallmarks of mucosa-associated lymphoid tissue (MALT) lymphoma. However, targeting these translocations to mouse B-cells has failed to reproduce human disease. Here, we induced MALT1 expression in mouse Sca1+Lin- hematopoietic stem/progenitor cells (HS/PCs), leading to the development of tumors recapitulating the clinical, histopathological and molecular features of human MALT lymphomas. Ablation of the p53 gene induced transformation of MALT lymphoma to diffuse large-cell lymphoma of activated B-cell type (ABC-DLBCL). Human CD34+ cells isolated from MALT lymphoma patients displayed an abnormal transcriptional program that was shared by MALT lymphoma cells, transgenic mouse Sca1+Lin- cells and Sca1-MALT1-induced lymphomas. Our study shows that MALT lymphoma can be modeled in mice by targeting MALT1 oncogene to HS/PCs.
Project description:To identify key tumour supressor miRNAs involed in MALT lymphoma pathogenesis Gastric mucosa-associated lymphoid tissue lymphoma develops in the chronically inflamed mucosa of Helicobacter pylori-infected patients. MicroRNA expression profiling of human MALT lymphoma revealed a 10-fold down-regulation of miR-203, which resulted from promoter hypermethylation and coincided with the dysregulation of the miR-203 target ABL1. Demethylating treatment of lymphoma B-cells led to an increase in miR-203 expression and concomitant ABL1 down-regulation. The lentiviral delivery of miR-203, as well as treatment with various ABL inhibitors, prevented primary MALT lymphoma cell proliferation in vitro. Finally, the treatment of tumor-bearing mice with imatinib induced MALT lymphoma regression in vivo. Our results show that MALT lymphomagenesis is epigenetically induced by miR-203 promoter methylation and identify ABL1 as a novel target for the treatment of this malignancy.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Attempts at modeling chromosomal translocations involving MALT1 gene, hallmarks of human mucosa-associated lymphoid tissue (MALT) lymphoma, have failed to reproduce the disease in mice. Here we describe a transgenic model in which MALT1 expression was targeted to mouse hematopoietic stem/progenitor cells. In Sca1-MALT1 mice, MALT1 deregulation activated the NF-kappaB pathway in Sca1+ cells, promoting selective B-cell differentiation and mature lymphocyte accumulation in extranodal tissues, progressively leading to the development of clonal B-cell lymphomas. These tumors recapitulated the histopathological features of human MALT lymphomas, presenting typical lymphoepithelial lesions and plasmacytic differentiation. Transcriptional profiling of Sca1-MALT1 murine lymphomas revealed overlapping molecular signatures with human MALT lymphomas, including MALT1-mediated NF-kappaB activation, pro-inflammatory signaling and XBP1-induced plasmacytic differentiation. Moreover, murine Malt1 showed proteolytic activity by cleaving Bcl10 in Sca1-MALT1 lymphomas. Our novel technological approach has allowed modeling human MALT lymphoma in mice, which represent unique tools study MALT lymphoma biology and evaluate anti-MALT1 therapies. Keywords: lymphoma profiling, MALT lymphoma
2012-07-10 | GSE25638 | GEO
Project description:pulmonary MALT lymphoma: a metagenomics investigation
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs. One-condition experment, gene expression of 3A6