MicroRNA-582-5p regulates cell invasion in bladder cancer through targeting Forkhead Box G1.

Burgeoning evidence shows that microRNAs (miRNAs) are associated with tumorigenesis and progression. However, the alteration and function of many miRNAs in bladder cancer (BCa) are not clear. Here, we explored the regulatory effect of microRNA-582 (miR-582) on cell invasion in BCa and underlying mechanisms. The expression of miR-582 in BCa tissues and cell lines was examined by quantitative real-time PCR (qRT-PCR). The target gene of miR-582 and their binding site were predicted by bioinformatics analysis. Luciferase reporter assay and western blot analysis were performed to confirm miR-582 directly targeting Forkhead Box G1 (FOXG1). The role of miR-582-FOXG1 axis in regulating BCa invasion was evaluated in cell models. The association of miR-582 with clinicopathologic features and prognosis was analyzed. Experimental results indicated that miR-582 was downregulated in BCa tissues and cell lines. Forced miR-582 decreased cell invasion, regulating expression levels of invasion-related proteins, such as MMP2, MMP9 and ZO-1. MiR-582 directly targeted FOXG1 by binding to its 3'UTR. Overexpression of FOXG1 rescued the regulating function in BCa cells induced by miR-582. Moreover, miR-582-FOXG1 axis has obvious clinical relevance with prognosis in BCa patients. Our results indicate that miR-582-FOXG1 axis may act as a key role on cell invasion and serve as a potential prognostic predicted biomarker.