Let-7c-5p inhibits cell proliferation and induces cell apoptosis by targeting ERCC6 in breast cancer.

In this study, we found that let-7c-5p expression was clearly downregulated in breast cancer tissues compared with that of corresponding adjacent tissues. Furthermore, overexpression of let-7c-5p in MCF-7 breast cancer cells could significantly inhibit cell proliferation and induce cell apoptosis. The target genes of let-7c-5p were predicted by the way of bioinformatics, and validated by dual luciferase reporter assay and western blotting demonstrating that excision repair cross complementing 6 (ERCC6) gene was a direct target. Collectively, the present study suggested that let-7c-5p acted as a tumor suppressor in breast cancer possibly by negatively regulating ERCC6, which took an important part in nucleotide excision repair and it may provide a new potential strategy for breast cancer therapy.