MAF Amplification licenses Estrogen Receptor a to Drive Breast Cancer Metastasis [RNA-seq]

We performed mRNA profiling of control and MAF-overexpressing MCF7 cells to assess the transcriptional consequences of estrogen receptor (ER) activation upon metastatic MAF expression. To this end, we cultured MCF7 cells in hormone-deprived (HD) medium for 72 h and then estrogen (E2) or vehicle was added for 6h prior to RNA extraction. Samples were generated in triplicate. We report that MAF supports the expression of genes involved in metastatic functions and that E2 treatment correlates with E2 early and late gene responses and cell cycle regulation. Additionally, a set of MAF and E2-dependent gene responses was identified. Our results show that MAF expression causes an expansion of ER-mediated transcriptional events in MCF7 cells exposed to E2. Additionally, we silenced KDM1A expression in MAF-overexpressing MCF7 cells to test whether this histone demethylase mediates the transcriptional consequences of MAF overexpression. Samples with KDM1A knockdown were generated in duplicates. We report that KDM1A partially regulates MAF/E2-dependent gene responses. Overall design: To assess gene expression changes governed by MAF and estrogen (E2), control or MAF-overexpressing MCF7 cells were maintained in hormone-deprived medium for 72 h. Then, E2 or vehicle was added for 6h prior to RNA extraction and mRNA profiling. To evaluate the effect of KDM1A expression on the regulation of MAF/E2-dependent gene responses, expression of the histone demethylase was silenced in MAF-overexpressing cells using shRNA followed by selection with 2µg/mL puromycin for 72 h. Then cells were cultured in hormone-deprived medium before E2 stimulation as previously explained.