Project description:miRNAs regulate mRNA stability and translation through the action of the RNAi-induced silencing complex. In this study, we systematically identified endogenous miRNA target genes by using AGO2 immunoprecipitation (AGO2-IP) and microarray analyses in two breast cancer cell lines, MCF7 and MDA-MB-231, representing luminal and basal-like breast cancer, respectively. The expression levels of ~70% of the AGO2-IP mRNAs were increased by DROSHA or DICER1 knockdown. In addition, integrated analysis of miRNA expression profiles, mRNA-AGO2 interaction, and the 3'-UTR of mRNAs revealed that >60% of the AGO2-IP mRNAs were putative targets of the fifty most abundantly expressed miRNAs. To identify mRNAs responsive to miRNA synthesis inhibition, total RNA was prepared from control cells and cells that stably express small hairpin RNA against DICER1 or DROSHA. Expression array analysis was performed with duplicates for each cell type.
Project description:miRNAs regulate mRNA stability and translation through the action of the RNAi-induced silencing complex. In this study, we systematically identified endogenous miRNA target genes by using AGO2 immunoprecipitation (AGO2-IP) and microarray analyses in two breast cancer cell lines, MCF7 and MDA-MB-231, representing luminal and basal-like breast cancer, respectively. The expression levels of ~70% of the AGO2-IP mRNAs were increased by DROSHA or DICER1 knockdown. In addition, integrated analysis of miRNA expression profiles, mRNA-AGO2 interaction, and the 3'-UTR of mRNAs revealed that >60% of the AGO2-IP mRNAs were putative targets of the fifty most abundantly expressed miRNAs.
Project description:miRNAs regulate mRNA stability and translation through the action of the RNAi-induced silencing complex. In this study, we systematically identified endogenous miRNA target genes by using AGO2 immunoprecipitation (AGO2-IP) and microarray analyses in two breast cancer cell lines, MCF7 and MDA-MB-231, representing luminal and basal-like breast cancer, respectively. The expression levels of ~70% of the AGO2-IP mRNAs were increased by DROSHA or DICER1 knockdown. In addition, integrated analysis of miRNA expression profiles, mRNA-AGO2 interaction, and the 3'-UTR of mRNAs revealed that >60% of the AGO2-IP mRNAs were putative targets of the fifty most abundantly expressed miRNAs.
Project description:miRNAs regulate mRNA stability and translation through the action of the RNAi-induced silencing complex. In this study, we systematically identified endogenous miRNA target genes by using AGO2 immunoprecipitation (AGO2-IP) and microarray analyses in two breast cancer cell lines, MCF7 and MDA-MB-231, representing luminal and basal-like breast cancer, respectively. The expression levels of ~70% of the AGO2-IP mRNAs were increased by DROSHA or DICER1 knockdown. In addition, integrated analysis of miRNA expression profiles, mRNA-AGO2 interaction, and the 3'-UTR of mRNAs revealed that >60% of the AGO2-IP mRNAs were putative targets of the fifty most abundantly expressed miRNAs. To identify mRNAs associated with AGO2, cell lysate was precleaned with control IgG and immunoprecipitated with anti-human Ago2 (Clone 2E12-1C9, Abnova). Total RNA from cell lysate or coimmunoprecipitated with AGO2 was extracted with Trizol and subjected to microarray analysis, with three biological repeats for each experimental condition.
Project description:The aim of the study is to identify miRNA specific targets in Hodgkin lymphoma cell lines. By immunoprecipitation (IP) of wild type Ago2, Ago2 associated gene transcripts (ie miRNA targets) are coimmunoprecipitated. In cells transfected with anti-miR-17/20/93/106, the miR-17 seed family specific targets are not coimmunoprecipitated with Ago2. With microarray analysis, signal intensities of probes associated with Ago2 from untransfected and anti-miRNA transfected cells are compared. Gene transcripts that are depleted from the Ago2-IP fraction upon miRNA inhibition (ie miRNA specific targets) are identified.
Project description:MicroRNAs (miRNAs) are small non-coding RNAs involved in the posttranscriptional regulation of gene expression. Deregulated miRNA levels have been reported in Burkitt lymphoma (BL) compared to normal B cells and a number of miRNA target genes have been identified in BL cell lines. Here, we determined for the first time the miRNA targetomes of primary BL tumors in comparison with normal B cells. AGO2-RNA immunoprecipitation (AGO2-RIP) in two frozen diagnostic BL tissue samples and three CD19+ B-cell samples isolated from routinely removed tonsils revealed distinct miRNA targetomes of BL and normal B cells. Targets of the miR-17~92 cluster were significantly more frequently AGO2-IP enriched in BL while targets of miR-29 and miR-150 were more frequently AGO2-IP enriched in normal B cells. Furthermore, we showed that miRNA target genes in BL are mainly involved in cell cycle and cell death. Immunohistochemistry on BL tumor samples and tonsil tissues confirmed altered protein levels for two out of six selected miRNA targets, in line with the differential AGO2-IP enrichment between BL and normal B cells. A comparison of AGO2-IP enriched genes in primary BL cases with BL cell lines indicated that approximately half of the miRNA targets may be missed in studies using BL cell lines, while almost 60% of miRNA target genes identified in cell lines were not AGO2-IP enriched in primary BL cases. Our results demonstrate both the necessity and feasibility of studying miRNA-target interactions in primary tumors.
2018-01-19 | GSE107325 | GEO
Project description:Identification of miRNA targets in breast cancer cells