Salinomycin-induced autophagy blocks apoptosis via the ATG3/AKT/mTOR signaling axis in PC-3 cells

Aims: This study evaluated the mechanism by which salinomycin-induced autophagy blocks apoptosis in PC-3 prostate cancer cells. Main methods: The anti-cancer effects of salinomycin in PC-3 cells were confirmed by flow cytometry, JC-1 staining and western blotting. Then, the autophagic effects were measured by western blotting, GFP-LC3 puncta formation assay, immunofluorescence staining and electron microscopy. Furthermore, we used lentivirus-mediated shRNA to silence ATG3, ATG5 and ATG7 expression in PC-3 cells to investigate the regulatory mechanisms of salinomycin-induced autophagy. Key findings: Salinomycin could induce apoptosis and autophagy in PC-3 cells. Interestingly, autophagy inhibition could enhance salinomycin-induced apoptosis. We further showed that ATG3, a known critical regulator of autophagy, was down regulated and involved in the inhibition of apoptosis by salinomycin-induced autophagy via the AKT/mTOR signaling axis. Significance: Our data indicated that salinomycin-induced autophagy blocks apoptosis via the ATG3/AKT/mTOR signaling axis in PC-3 cells, which provides new clues for the mechanisms of underlying the anti-cancer effects of salinomycin.