miRNA-182-5p promotes human bladder cancer proliferation and migration through the FOXF2/SHH axis
Ze Zhang, Chong Wang, Tiantian Liu, Zhao Tang, Rucheng Yan, Chen Zhang, Chao Cheng, Jiawei Wang, Hao Wang, Houbao Huang, Yawei Li
Abstract
Increasing evidence suggests that microRNAs (miRNAs) play critical roles in bladder tumorigenesis and development by combining with the 3' untranslated regions (3'-UTRs) of the corresponding mRNAs to negatively regulate gene expression. The role of miR-182-5p in bladder cancer (BC) remains unclear. Therefore, this study aimed to clarify the functional role of miR-182-5p in BC. We predicted candidate mRNAs for miR-182-5p via three databases (TarBase, ENCORI, and miRDB). Dual-luciferase reporter assays and target prediction confirmed FOXF2 as a potential target of miR-182-5p. Quantitative RT-PCR (qRT-PCR) showed that endogenous miR-182-5p expression was significantly upregulated in BC cell lines and clinical samples of BC patients. IHC, western blotting, and qRT-PCR assays indicated that FOXF2 expression was concurrently downregulated in BC tissues and BC cell lines. Gain- and loss-of-function studies showed that the overexpression of miR-182-5p enhanced the proliferation and migration of BC cells, while the downregulation of miR-182-5p showed the opposite results. The effects induced by miR-182-5p were attenuated with the restoration of FOXF2 expression. In BC cells, the upregulation of miR-182-5p not only decreased FOXF2 expression but also markedly increased Sonic hedgehog (SHH) pathway levels. These findings suggested that FOXF2 directly binds to miR-182-5p and that miR-182-5p acts as a tumor promoter in BC genesis and metastasis by targeting FOXF2. In addition, miR-182-5p plays a pro-cancer role by downregulating FOXF2 and activating the SHH pathway.