Effects of platelet-activating factor (PAF) on epidermal growth factor receptor (EGFR) activation in SKOV-3 cells. (A) SKOV-3 cells were treated with 100 nM PAF for 0, 5, 10, 15, 20, or 25 min. Following PAF treatment, the cells were lysed, and the lysates were evaluated by Western blotting. Data were normalized to total EGFR protein expression and are expressed as fold-change (average ± S.E.M.) in phospho-EGFR compared with vehicle-treated cells. Representative blots for phosphor/total-EGFR are shown. (B) SKOV-3 cells were treated with vehicle (0) or 0.1 to 1000 nM PAF for 5 min. Fold-phosphorylation data for immunoreactivity with antibodies against p-EGFR are shown in representative Western blots. (C) SKOV-3 cells were treated with AG1478 (20 μM) for 1 hour before stimulation with PAF (100 nM) or EGF (5 ng/ml) for 5 min. Cells were harvested and subjected to Western blotting. The data shown are representative of at least three independent experiments. Data were analyzed using Student’st-test. * p < 0.05.