Project description:Triple-negative breast cancer is a highly aggressive tumor subtype that lacks effective therapeutic targets. Here, we show that ELK3 is overexpressed in a subset of breast cancers, in particular basal-like and normal-like/claudin-low cell lines. Suppression of ELK3 in MDA-MB-231 cells led to transdifferentiation from an invasive mesenchymal phenotype to a non-invasive epithelial phenotype both in vitro and in vivo. Suppression of ELK3 results in the extensive changes in genome expression profiles. Among these, GATA3, a master suppressor of metastasis, was epigenetically activated and we found that suppression of GATA3 led to the restoration of migration and invasion. These results suggest that the ELK3-GATA3 axis is a major pathway that promotes metastasis of MDA-MB-231 cells. Retrovirus expressing shRNA of ELK3 was transduced into MDA-MB-231 cell line and stable cell line of which ELK3 is suppressed more than 50% was selected by the drug selection (Puromycin).
Project description:Triple-negative breast cancer is a highly aggressive tumor subtype that lacks effective therapeutic targets. Here, we show that ELK3 is overexpressed in a subset of breast cancers, in particular basal-like and normal-like/claudin-low cell lines. Suppression of ELK3 in MDA-MB-231 cells led to transdifferentiation from an invasive mesenchymal phenotype to a non-invasive epithelial phenotype both in vitro and in vivo. Suppression of ELK3 results in the extensive changes in genome expression profiles. Among these, GATA3, a master suppressor of metastasis, was epigenetically activated and we found that suppression of GATA3 led to the restoration of migration and invasion. These results suggest that the ELK3-GATA3 axis is a major pathway that promotes metastasis of MDA-MB-231 cells.
Project description:Dicer, RNase III endonuclease, is an essential enzyme in miRNA biogenesis that regulates target gene expression, and it has been reported that aberrant expressions of Dicer associate with the clinical outcomes of patients in various cancers. To explore the miRNA differencial expression regulated by Dicer in MDA-MB-231/E1A cells, the microarray profiling analysis was employed to conduct differentially expressed miRNAs in stable MDA-MB-231/vector, MDA-MB-231/E1A, and MDA-MB-231/E1A/shDicer cells.
Project description:To investigate the function of SNHG14 in breast cancer, we established MDA-MB-231 cell lines in which this gene has been knocked down by siRNA.
Project description:Identification of genes that are involved in self-seeding by comparing gene expression profiles between parental MDA-MB-231 cells and seeder cells (MDA-231-S1a and S1b) 2 replicates from each sample (parental MDA-MB-231, MDA-MB-231 S1a and MDA-MB-231 S1b) were analyzed
Project description:Dicer, RNase III endonuclease, is an essential enzyme in miRNA biogenesis that regulates target gene expression, and it has been reported that aberrant expressions of Dicer associate with the clinical outcomes of patients in various cancers. To explore the miRNA differencial expression regulated by Dicer in MDA-MB-231/E1A cells, the microarray profiling analysis was employed to conduct differentially expressed miRNAs in stable MDA-MB-231/vector, MDA-MB-231/E1A, and MDA-MB-231/E1A/shDicer cells. The four groups including vector control, E1A-expressing and Dicer knockdown in E1A-expressing MDA-MB-231 cells were harvested and RNA were isolated. Two independent experiments were performed for each group.
Project description:RhoGDIbeta (ARHGDIB) is often expressed in tumor cells. It negatively regulates Rho-GTPases, but may have other functions as well. To analyze its effect on gene expression, RhoGDIbeta was suppressed by RNA interference in MDA-MB-231 breast cancer cells and changes in gene expression monitored by cDNA microarrays. Experiment Overall Design: MDA-MB-231 cells were either transfected with a RhoGDIbeta-specific siRNA or a control siRNA (siLuc), grown for three days, harvested and lysed for total RNA isolation. RNA was subjected to cDNA microarray analysis by using Affymetrix chip HG-U133A. A total of three independent transfection experiments were performed. The samples obtained from experiments 1, 2 and 3 were designated as siLuc_rep1, siLuc_rep2, siLuc_rep3 (siLuc transfected) and siARH_rep1, siARH_rep2, siARH_rep3 (siRhoGDIbeta transfected), respectively.
Project description:To identify the downstream target genes of PUS1 on breast cancer cells, we established MDA-MB-231 cell lines in which PUS1 has been knocked down by shRNA. We then performed gene expression profiling analysis using data obtained from RNA-seq of PUS1 knockdownMDA-MB-231 cells as well as negative control shRNA group
Project description:To investigate the function NatD in the regulation of breast cancer progression, we established MDA-MB-231 cell lines in which each target gene has been knocked down by CRISPR.