MicroRNA-613 induces the sensitivity of gastric cancer cells to cisplatin through targeting SOX9 expression.

Increasing evidences have suggested that deregulated miRNAs may involve in drug chemoresistance in a lot of human cancers. However, the role of miR-613 in drug chemoresistance of GC cell is still unknown. The expression of miR-613 and Sex-determining region Y (SRY)-box 9 (SOX9) in GC tissues and cell lines was detected by using qRT-PCR. Cell migration and viability were measured by the wound healing assay and CCK-8 assays. Western blot and dual-luciferase reporter were done to identify the target gene of miR-613. We showed that miR-613 expression was downregulated in GC tissues and cell lines. Ectopic expression of miR-613 increased the sensitivity of GC cells to cisplatin. Overexpression of miR-613 suppressed GC cell proliferation, cycle and migration. In addition, we identified SOX9 was a direct target gene of miR-613 in GC cell. We showed that SOX9 expression was upregulated in gastric cancer samples. Moreover, the expression of SOX9 was negatively correlated with miR-613 expression in GC tissues. Furthermore, elevated expression of miR-613 increased the sensitivity of GC cells to cisplatin and suppressed GC cell proliferation and migration by targeting SOX9. These data suggested that miR-613 might function as a chemoresistant suppressor in GC.