Epigenetic regulation of miRNA in CLL [MCIp_hsa_miRNA_v3b]
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE33623 | GEO | 2012/05/31
SECONDARY ACCESSION(S): PRJNA156667
REPOSITORIES: GEO
Similar Datasets
Project description:Genome-wide profiling of DNA methylation 35 kb upstream and 5 kb downstream of microRNAs in 24 CLL patients and B cells of 2 healthy donors versus a pool of 10 healthy donors. 26 samples total (24 CLL B cell samples and 2 healthy donor B cell samples) were hybridized against a pool of 10 healthy donor B cell samples.
2012-05-30 | E-GEOD-33623 | biostudies-arrayexpress
Project description:Understanding the crosstalk between malignant B-cells and their milieu could provide clues on the molecular and clinical biology of Chronic Lymphocytic Leukemia (CLL). Aiming to generate novel therapeutic strategies, different groups have studied different CLL proliferative fractions. We previously, identified one of these proliferative subsets in the peripheral blood from progressive unmutated CLL patients. Since the presence of this small subset appears to be a hallmark of a proliferative disease in which B lymphocytes are being constitutively activated in the proliferative centers of these patients, we performed gene expression analysis comparing the global mRNA and microRNAs expression of this leukemic subpopulation. Our results suggest that the proliferative behaviour of this fraction appears to depend on microRNA-22 over-expression, which induces PTEN downregulation and PI3K/AKT pathway activation. Transfection experiments demonstrated that miR-22 overexpression in CLL B-cells switches on PI3K/AKT leading to FOXO1 inactivation, p27-Kip1 downregulation, and overexpression of Survivin and Ki-67 proteins. We also demonstrated that this pathway could be triggered by microenvironment signals like CD40L/IL4 and more importantly, that this regulatory loop is also present in lymph nodes from progressive UM patients. Altogether, these results underline the key role of PI3K/AKT pathway in the generation of the CLL proliferative pool and provide rationale for the usage of PI3K inhibitors.
2014-05-15 | GSE53235 | GEO
Project description:In order to investigate a potential involvement of miRNAs in BCR stimulation, in the present work we first evaluated their expression following IgM cross-linking in CLL cells, as well as in healthy B lymphocytes. Next, to infer putative miRNA targeting networks, we combined miRNA profiling results with gene expression and functional analyses miRNA expression profiling analysis by microarray analysis of CLL samples and pools of CD19+ cells derived from healthy donors.
2015-02-10 | E-GEOD-49696 | biostudies-arrayexpress
Project description:Understanding the crosstalk between malignant B-cells and their milieu could provide clues on the molecular and clinical biology of Chronic Lymphocytic Leukemia (CLL). Aiming to generate novel therapeutic strategies, different groups have studied different CLL proliferative fractions. We previously, identified one of these proliferative subsets in the peripheral blood from progressive unmutated CLL patients. Since the presence of this small subset appears to be a hallmark of a proliferative disease in which B lymphocytes are being constitutively activated in the proliferative centers of these patients, we performed gene expression analysis comparing the global mRNA and microRNAs expression of this leukemic subpopulation. Our results suggest that the proliferative behaviour of this fraction appears to depend on microRNA-22 over-expression, which induces PTEN downregulation and PI3K/AKT pathway activation. Transfection experiments demonstrated that miR-22 overexpression in CLL B-cells switches on PI3K/AKT leading to FOXO1 inactivation, p27-Kip1 downregulation, and overexpression of Survivin and Ki-67 proteins. We also demonstrated that this pathway could be triggered by microenvironment signals like CD40L/IL4 and more importantly, that this regulatory loop is also present in lymph nodes from progressive UM patients. Altogether, these results underline the key role of PI3K/AKT pathway in the generation of the CLL proliferative pool and provide rationale for the usage of PI3K inhibitors. B cells from Chronic Lymphpcytic Leukaemia patients were isolated from blood. By sorting experiments we purify the QF from PF from progressive patients. We extract the total RNA from 8 samples and perform microRNA arrays.
2014-05-15 | E-GEOD-53235 | biostudies-arrayexpress
Project description:T cells may have a role in sustaining the leukemic clone in chronic lymphocytic leukemia (CLL). In this study, we have examined the ability of T cells from CLL patients to support the survival of the leukemic B cells in vitro. Additionally, we compared global gene expression of T cells from indolent CLL patients with healthy individuals and multiple myeloma (MM) patients. Apoptosis of purified CLL cells was inhibited in vitro when cocultured with increasing numbers of autologous T cells (p<0.01) but not with normal donors. The anti-apoptotic effect exceeded that of the antiapoptotic cytokine IL-4 (p=0.02) and was greater with CD8+ T cells than with CD4+ cells (p<0.05). The effect depended mainly on cell-cell contact although a significant effect was observed in transwell experiments (p<0.05). Additionally, about 356 genes involved in different cellular pathways were deregulated in T cells of CLL patients compared to healthy individuals and MM patients. The results of gene expression profiling was verified for 7 genes (KLF6, TRAF1, CCL4, CCL5, RANTES, XCL1 and XCL2) using qRT-PCR and immunoblotting. Our results demonstrate that CLL-derived T cells can prevent apoptosis of leukemic cells and have altered expression of genes that may facilitate survival of the leukemic clone.
2011-03-24 | GSE28107 | GEO
Project description:Understanding the crosstalk between malignant B-cells and their milieu could provide clues on the molecular and clinical biology of Chronic Lymphocytic Leukemia (CLL). Aiming to generate novel therapeutic strategies, different groups have studied different CLL proliferative fractions. We previously, identified one of these proliferative subsets in the peripheral blood from progressive unmutated CLL patients. Since the presence of this small subset appears to be a hallmark of a proliferative disease in which B lymphocytes are being constitutively activated in the proliferative centers of these patients, we performed gene expression analysis comparing the global mRNA and microRNAs expression of this leukemic subpopulation. Our results suggest that the proliferative behaviour of this fraction appears to depend on microRNA-22 over-expression, which induces PTEN downregulation and PI3K/AKT pathway activation. Transfection experiments demonstrated that miR-22 overexpression in CLL B-cells switches on PI3K/AKT leading to FOXO1 inactivation, p27-Kip1 downregulation, and overexpression of Survivin and Ki-67 proteins. We also demonstrated that this pathway could be triggered by microenvironment signals like CD40L/IL4 and more importantly, that this regulatory loop is also present in lymph nodes from progressive UM patients. Altogether, these results underline the key role of PI3K/AKT pathway in the generation of the CLL proliferative pool and provide rationale for the usage of PI3K inhibitors.
2014-05-15 | GSE53236 | GEO
Project description:T cells may have a role in sustaining the leukemic clone in chronic lymphocytic leukemia (CLL). In this study, we have examined the ability of T cells from CLL patients to support the survival of the leukemic B cells in vitro. Additionally, we compared global gene expression of T cells from indolent CLL patients with healthy individuals and multiple myeloma (MM) patients. Apoptosis of purified CLL cells was inhibited in vitro when cocultured with increasing numbers of autologous T cells (p<0.01) but not with normal donors. The anti-apoptotic effect exceeded that of the antiapoptotic cytokine IL-4 (p=0.02) and was greater with CD8+ T cells than with CD4+ cells (p<0.05). The effect depended mainly on cell-cell contact although a significant effect was observed in transwell experiments (p<0.05). Additionally, about 356 genes involved in different cellular pathways were deregulated in T cells of CLL patients compared to healthy individuals and MM patients. The results of gene expression profiling was verified for 7 genes (KLF6, TRAF1, CCL4, CCL5, RANTES, XCL1 and XCL2) using qRT-PCR and immunoblotting. Our results demonstrate that CLL-derived T cells can prevent apoptosis of leukemic cells and have altered expression of genes that may facilitate survival of the leukemic clone. Peripheral blood was collected by venipuncture from CLL patients, multiple myeloma (MM) patients and age-matched healthy individuals with informed consent and approval of the local Ethics Committee in keeping with the Helsinki declaration on the use of human subjects for research.
2011-03-23 | E-GEOD-28107 | biostudies-arrayexpress
Project description:CD14+ cells in the PBMCs of CLL patients are converted into NLCs. CD14+ PBMCs from healthy donors when cultured with CLL cells give rise to differentiated cells called CD14CLL-cells, which are immunophenotypically similar to NLCs. CD14+ PBMCs from healthy donors when cultured with non-malignant B cells give rise to differentiated cells called CD14B-cells. Transcriptome wide analysis reveals genes involved in immune response to be significantly deregulated between CD14B-cells and CD14CLL-cells/NLCs.
2013-01-01 | GSE21838 | GEO
Project description:Understanding the crosstalk between malignant B-cells and their milieu could provide clues on the molecular and clinical biology of Chronic Lymphocytic Leukemia (CLL). Aiming to generate novel therapeutic strategies, different groups have studied different CLL proliferative fractions. We previously, identified one of these proliferative subsets in the peripheral blood from progressive unmutated CLL patients. Since the presence of this small subset appears to be a hallmark of a proliferative disease in which B lymphocytes are being constitutively activated in the proliferative centers of these patients, we performed gene expression analysis comparing the global mRNA and microRNAs expression of this leukemic subpopulation. Our results suggest that the proliferative behaviour of this fraction appears to depend on microRNA-22 over-expression, which induces PTEN downregulation and PI3K/AKT pathway activation. Transfection experiments demonstrated that miR-22 overexpression in CLL B-cells switches on PI3K/AKT leading to FOXO1 inactivation, p27-Kip1 downregulation, and overexpression of Survivin and Ki-67 proteins. We also demonstrated that this pathway could be triggered by microenvironment signals like CD40L/IL4 and more importantly, that this regulatory loop is also present in lymph nodes from progressive UM patients. Altogether, these results underline the key role of PI3K/AKT pathway in the generation of the CLL proliferative pool and provide rationale for the usage of PI3K inhibitors. Two-subset of B cells, QF vs PF. 8 samples of 4 patients.
2014-05-15 | E-GEOD-53236 | biostudies-arrayexpress