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 (TGFα) 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 TGFα 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 TGFα 3′-UTR.RESULTS
TGFα 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 TGFα knockdown significantly reduced the migratory and invasive capabilities of PCa cells in vitro. TGFα is a direct target gene of miR-152.CONCLUSIONS
Our findings suggest that miR-152 can act as a tumor suppressor that targets TGFα. miR-152 is a promising molecular target that inhibits PCa cell migration and invasion. Prostate 73: 1082–1089, 2013. © 2013 Wiley Periodicals, Inc.