MiR-210-3p inhibits the tumor growth and metastasis of bladder cancer via targeting fibroblast growth factor receptor-like 1.

Current evidence indicates that microRNAs are widely down-regulated in various tumors including colorectal carcinoma, liver cancer and lung cancer, and function as tumor suppressors through inhibiting cancer cell growth, invasion and migration. Here, we demonstrated that miR-210-3p level was significantly reduced in the bladder cancer compared to paratumor tissues, and attempt to reveal the regulatory role of miR-210-3p in bladder cancer progression. Exogenous overexpression of miR-210-3p inhibited the proliferation, migration and invasion of bladder cancer cells in vitro. In addition, the nude mouse xenograft model showed that miR-210-3p over-expressing inhibited bladder cancer growth and liver metastasis whereas silencing miR-210-3p caused an opposite outcome, which is mainly regulated by targeting fibroblast growth factor receptor-like 1 (FGFRL1). We also demonstrated that the expression of FGFRL1 in bladder cancer specimens were negatively correlated with miR-210-3p level, and FGFRL1 overexpression rescued the cell proliferation and invasion inhibited by ectopic expression of miR-210-3p. Moreover, knockdown of FGFRL1 was able to mimic the cell growth and metastasis effects induced by miR-210-3p over-expressing in bladder cancer cells. Together, these results indicate that miR-210-3p plays an important role in the regulation of bladder cancer growth and metastasis in vitro and in vivo through targeting FGFRL1.