Fig. 5.

EGF promotes colony formation and combination treatment exerts inhibitory effects on EGF activated‐STAT3 phosphorylation. (A, B) Colony formation was detected with or without EGF for 12 days. (C, D) Serum‐starved HCC cells were pretreated with or without 8000 nm sorafenib combined with 100 nm CuB for 12 h, then incubated with or without 10 ng·mL⁻¹ EGF for 30 min. The expression levels of phospho‐STAT3 and STAT3 were analyzed by western blotting. GAPDH was used as a loading control. Data are presented as the mean ± SD from three independent experiments. Differences between two groups were analyzed using Student’s t‐test. *P < 0.05 and **P < 0.01 vs. the corresponding group.