miR-590-3p inhibits proliferation and promotes apoptosis by targeting activating transcription factor 3 in human breast cancer cells.

We previously reported that ATF3 and Runx2 are involved in breast cancer progression and bone metastasis. The expression of these genes can be controlled by post-transcriptional regulators such as microRNAs (miRNAs). In this study, we identified and validated the functional role of miR-590-3p in human breast cancer cells (MDA-MB231). There was an inverse correlation between the expression of miR-590-3p and its putative target genes, ATF3 and Runx2 in these cells. Overexpression of miR-590-3p decreased the expression of ATF3 and Runx2 at the mRNA and protein levels in MDA-MB231 cells. Luciferase reporter assay identified a direct interaction of 3' UTRs of ATF3 and Runx2 with miR-590-3p in these cells. Overexpression of miR-590-3p also decreased proliferation and increased apoptosis of breast cancer cells. Based on our results, we suggest that miR-590-3p might have potential clinical applications towards controlling breast cancer progression and bone metastasis.