Formononetin inhibits human bladder cancer cell proliferation and invasiveness via regulation of miR-21 and PTEN.

The isoflavone formononetin is the main active component of Astragalus membranaceus and possesses anti-tumorigenic properties. However, the role of formononetin in human bladder cancer (BCa) has not been fully elucidated. The aim of the present study was to investigate the anti-tumor effects of formononetin on BCa cells and its potential molecular mechanism. T24 cells were treated with different concentrations of formononetin, and then the cell proliferation was assessed by MTT assay, cell apoptosis by Hoechst 33258 stain assay, cell invasiveness by transwell invasion assay, microRNA-21 (miR-21) expression by real-time PCR and the protein level of phosphatase and tensin homolog (PTEN) and phosphorylated homolog of Akt (p-Akt) by western blotting. The results showed that formononetin significantly inhibited the proliferation of T24 cells in a time- and dose-dependent manner. T24 cells treated with formononetin displayed obvious morphological changes of apoptosis and lower invasiveness. In addition, miR-21 expression was significantly decreased in formononetin-treated T24 cells, followed by increase of PTEN, and down-regulation of p-Akt. Collectively, these results suggest that formononetin exerts an anti-carcinogenic effect on BCa in vitro, which might be due to miR-21-mediated regulation of the PTEN/Akt pathway.