Project description:This SuperSeries is composed of the following subset Series: GSE28968: MRNA expression data from human breast cancer cell lines after demethylation treatment. GSE28969: MicroRNA expression data from human breast cancer cell lines after demethylation treatment. Refer to individual Series
Project description:The contribution of aberrant DNA methylation and the downstream effects in tumorogenesis through silencing of tumor suppressor genes (TSGs) and microRNAs has been investigated. Since these epigenetic alterations can be reversed, we investigated the effects of the epigenetic therapy in breast cancer cell lines. We used microarrays to investigate the global gene expression profile after demethylation treatment with 5-aza-2’-deoxycytidine (DAC) in breast cancer cell lines and identified distinct classes of early and late systematic stable or transient effects of the treatment. Three selected breast cell lines including MDA-MB231 (a highly aggressive cell line), SKBR3 (a non-aggressive cell line) and HB2 (a breast epithelial cell line as control) were subject for RNA isolation before treatment, after treatment with DAC and at five point follow-ups (1st, 3rd, 5th, 7th and 10th passages) at “drug holiday” condition and hybridized on Affymetrix microarrays.