Western blot analysis of autophagy-related proteins after AB4 treatment. A and B. SMMC7721 cells were treated with 20, 40 and 80 μM AB4 for 24 h. Western blot analysis was performed to analysis the expression of autophagy-related proteins, including LC3, Beclin-1 and p62. β-actin was used for equal loading. *P < 0.05, **P < 0.01 versus vehicle control group. C and D. SMMC7721 cells were pre-treated with 20 μM CQ for 1 h, followed by 24 h of AB4 treatment. Autophagy-related proteins were detected by Western blot and quantitatively analyzed. *P < 0.05, **P < 0.01 versus vehicle control group.