miR-152 controls migration and invasive potential by targeting TGFα in prostate cancer cell lines

BACKGROUND MicroRNAs (miRNAs) are a class of short non-coding RNAs that function in diverse biological processes. Aberrant miR-152 expression has been frequently reported in various malignant tumors. However, the mechanism of miR-152 in prostate cancer (PCa) remains unclear. This study aims to determine the function of miR-152 in PCa cells and identify the novel molecular targets regulated by miR-152. METHODS The expression levels of transforming growth factor-alpha (TGF) were determined in three samples of PCa and adjacent non-tumorous tissues by Western blot analysis. miR-152 levels in 48 primary PCa and 15 non-malignant tissue samples were measured by qRT-PCR. The effects of forced miR-152 expression or TGF knockdown on PCa cells were evaluated by cell migration and invasion assays, as well as Western blot analysis. Dual-luciferase reporter assay was used to identify binding sites between miR-152 and TGF 3-UTR. RESULTS TGF was upregulated in PCa tissue samples compared with that in adjacent normal ones. miR-152 expression was significantly decreased in primary PCa samples compared with that in non-malignant samples. Patients with Gleason scores >7 exhibited lower miR-152 levels than those with lower scores. Moreover, low miR-152 expression is correlated with advanced pathological T-stages. Forced miR-152 expression or TGF knockdown significantly reduced the migratory and invasive capabilities of PCa cells in vitro. TGF is a direct target gene of miR-152. CONCLUSIONS Our findings suggest that miR-152 can act as a tumor suppressor that targets TGF. miR-152 is a promising molecular target that inhibits PCa cell migration and invasion. Prostate 73: 1082-1089, 2013. (c) 2013 Wiley Periodicals, Inc.