Figure 4. ISO induces autophagy through the AMPK/mTOR/p70S6K signaling pathway. (A) Western blotting analysis of AMPK, mTOR, p70S6K and their phosphorylated forms in HepG2 and Huh7 cells treated with increasing concentrations of ISO or 0.2% DMSO (vehicle) for 48 h. (B) Densitometric analysis of autophagy-related proteins. p-AMPK, AMPK, and LC3-II expression was detected after blocking AMPK activation with dorsomorphin (C, D) or si-AMPK (F, G); GAPDH served as loading control. (E, H) CellTiter-Blue viability assay results from HCC cells treated with 400 μM ISO for 48 h in the presence or absence of dorsomorphin or si-AMPK. Values represent mean ± SD; *p < 0.05, **p < 0.01, ***p < 0.001.