Autophagy inhibition rescues TRAIL-mediated apoptosis sensitization by Can by promoting autophagy flux. DU145 cells were pretreated with CQ (10 μM) for 1 h prior to their exposure to Can (1 μM) for 18 h. (A) The levels of LC3-II and p62 were assessed by western blot analysis. (B) Cells were immunostained with p62 (green) and evaluated for fluorescence (scale bar=50 μm; magnification, ×200). (C) DU145 cells were pretreated with CQ (10 μM) for 1 h prior to their exposure to Can (1 μM) for 18 h and then to TRAIL for an additional 1 h. The levels of Ac-cas3 and Ac-cas8 were then assessed by western blot analysis. TRAIL, tumor necrosis factor-related apoptosis-inducing ligand; CQ, chloroquine; can, cantharidin; LC3, microtubule-associated proteins 1A/1B light chain 3B; p62, sequestosome 1; Ac-cas, activated caspase.