Down-regulation of microRNA-224 -inhibites growth and epithelial-to-mesenchymal transition phenotype -via modulating SUFU expression in bladder cancer cells

Aberrant expression of miR-224 is usually found in cancer studies; however, the role of miR-224 has seldom been reported in bladder cancer (BC). We explored miR-224's function and the underlying mechanism in BC. It was found that miR-224 expression was significantly up-regulated in BC tissues and cell lines. Knockdown of miR-224 decreased BC cell growth and invasion both in vitro and in vivo. We identified the SUFU protein as a downstream target of miR-224 by using luciferase and western blot assays. We proposed that miR-224 promoted BC cell growth and invasion via sustaining the activity of Hedgehog pathway, which was negatively regulated by SUFU. Taken together, our study demonstrated that miR-224 may function as an onco-miR in BC and suggested that miR-224 may be a potential therapeutic target for BC patients.