Fig. 6. EGFR inhibition activity of complex 2f (a) and the reference inhibitor 1b (b) in EGFR-overexpressing A431 cells. (c) Effects of complex 2f and 1b on P-ERK, ERK, P-MEK and MEK protein expression. A431 cells were treated with 2f for 12 h. The protein levels were revealed by western blot assay. (d) Effects of complex 2f on the transcription activity of downstream protein AP-1. A431 cells were transfected with AP-1 luciferase plasmid for 48 h, and then treated with 2f at different concentration. AP-1 transcription activity was detected.