Fig. 1

a PC9 cells were incubated with various concentrations of EGF, and whole cell lysates were extracted and were examined by immunoblot analysis. b, c. Effects of gefitinib and mithramycin A on ERK, Sp1, and DPD in immunoblot analysis. PC9 cells were pretreated with gefitinib (1 μM) or mithramycin A (50 nM) before administration of 10 ng/ml EGF. After treatment, whole cell lysates were extracted and examined by western blotting. Results are representative of two independent experiments. d PC9 cells were stimulated with inhibitors, and nuclear extracts were prepared to detect the Sp1/DNA interaction by a Trans AM Sp1 kit. The experiment was performed in triplicate. *, p-value < 0.05