Mir-612 Inhibits Proliferation and Invasion of Urothelial Carcinoma of Bladder Cells Through Activating Hippo Pathway Via Targeting PMEPA1

Urothelial carcinoma of bladder (UCB) is a common urological malignancy in the world, but its progression mechanism remains unclear. MiR-612 was found as an anti-tumor factor in multiple types of cancer, while few studies have revealed its functions in UCB cells. Based on this, UCB cells such as HTB-9 and HTB-4, and normal urothelial of bladder cells such as SV-Huc1, were used as subjects in this study. Western blot, qRT-PCR, CCK-8 assay and transwell assay were used to assess functions of miR-612 in UCB cells. The database, miRWalk, was used to search for potential targets of miR-612, and dual-luciferase reporter assay was used to verify the accuracy of the forecasting results. Besides, PMEPA1 overexpressed vector and miR-612 mimics were co-transfected into HTB-4 to observe the regulation mechanism of miR-612. It was found that miR-612 was significantly downregulated in HTB-9 and HTB-4 cells rather than in SV-Huc 1 cells, and overexpressed miR-612 reduced the proliferation and invasion of HTB-4 cells. The expression level of YAP1 was negatively related with miR-612 while LATS1 was positively related with miR-612. Besides, the results of miRWalk and dual-luciferase reporter assay indicated that PMEPA1 was a target of miR-612, and overexpression of PMEPA1 could reverse the effects of miR-612 on UCB including weakened proliferation and invasion abilities, low expression level of YAP1 and high expression level of LATS1. Therefore, this study suggests that miR-612 inhibits the proliferation and invasion of urothelial carcinoma of bladder cells through activating Hippo pathway via targeting PMEPA1.