Figure 5

Effect of STI571 on growth factor-induced EGFR phosphorylation. Mia-PaCa-2 and T3M4 cell lines were cultured in 1% FCS medium overnight, then treated with 10 ng/ml of EGF and GI50 concentrations of STI571 for 5 minutes. Phosphorylation of EGFR was determined by Western blot analysis with a phospho-EGFR-specific antibody. Equal loading was determined by stripping the membranes and blotting with an antibody to ERK2 (p42). The figure is representative of three independent experiments.