MicroRNA-138 inhibits proliferation and migration of breast cancer cells by targeting c-Met

MicroRNAs (miRNAs) have been considered as critical post-transcriptional regulators involved in multiple biological processes. Previous studies demonstrated that microRNA-138 (miR-138) plays an important role in the pathogenesis of cancers, but its role in breast cancers has not been elucidated. In the present study, the expression of miR-138 was determined by real time PCR. MTT assay, wound healing assay, and colony formation assay were used to measure cell proliferation, migration and colony formation, respectively. The expression of c-Met was assessed by real time PCR and western blot. Luciferase assay was performed to validate the potential targets of miR-138. Results showed that the expression of miR-138 was significantly down-regulated in both breast cancer tissues and cell lines. Moreover, over-expression of miR-138 inhibited cell proliferation and migration in breast cancer cells. In addition, miR-138 up-regulation resulted in a reduction in c-Met expression, whereas inhibition of miR-138 enhanced c-Met level in breast cancer cells. The luciferase reporter assay further suggested that c-Met is a direct target of miR-138 in breast cancer cells. Taken together, our study demonstrated that miR-138 suppressed cell proliferation and migration via c-Met, providing a novel target for the molecular treatment of breast cancer.