Objective To investigate the effects of quercetin on cell viability,apoptosis,autophagy,and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)signaling pathway in human prostate cell carcinoma PC-3 cells.Methods PC-3 cells were cultured in vitro,and cell viability was detected by CCK-8.Apoptosis was detected by TUNEL staining.Autophagy vesicle was observed by acridine orange staining.Autophagosomes was observed by GFP-LC3 plasmid transfection analysis.Expressions of autophagy-related protein microtubule associated protein 1 light chain 3 fusion protein(LC3)and Beclin-1 and PI3K/Akt/mTOR signaling pathway protein were detected by Western blot analysis.Results Quercetin inhibited cell viability in a dose-time dependent manner and induced apoptosis.Quercetin increased the number of autophagy vesicles and autophagosomes in PC-3 cells.Quercetin increased the expressions of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 in PC-3 cells and decreased the expression of phosphorylated-PI3K,phosphorylated-Akt and phosphorylated-mTOR.Conclusion Quercetin may induce autophagy by inactivating PI3K/Akt/mTOR signaling pathway in PC-3 cells.
Keywords: autophagy; phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway; prostate cancer; quercetin.