MicroRNA-338-3p inhibits the progression of bladder cancer through regulating ETS1 expression

OBJECTIVE: MicroRNA-338-3p (miR-338-3p) was reported to influence the metastasis and development of several human cancers. However, in bladder cancer (BC), the special function of miR-338-3p remains unknown. Here, we aimed at exploring the miR-338-3p function in the progression of BC. PATIENTS AND METHODS: miR-338-3p and ETS1 expressions were examined by quantitative Real-time polymerase chain reaction (qRT-PCR) in BC samples. Following that, transwell assays for cell migration and invasion were performed. And MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay for cell proliferation was conducted as well. Western blot was employed to examine the epithelial-mesenchymal transition (EMT) marker expressions. Finally, the relationship between miR-338-3p and E26 transformation specific-1 (ETS1) was verified by luciferase reporter assay. RESULTS: The decreased miR-338-3p expression was examined in BC cells. Moreover, miR-338-3p upregulation repressed cell proliferation ability in BC. Next, miR-338-3p upregulation also depressed cell metastasis and EMT in BC cells. Furthermore, ETS1 was a direct target of miR-338-3p and inversely associated with its expression. And upregulation of ETS1 partially rescued the suppression of miR-338-3p for cell proliferation and metastasis in BC. CONCLUSIONS: Upregulation of miR-338-3p inhibited the proliferation, metastasis and EMT in BC by suppressing ETS, showing that miR-338-3p might block the development of BC through regulating ETS1 expression.