MDA MB468 cells serum-starved overnight were pre-incubated (or not) with 10 μM AG1478 or 2 μM PD 153035 for 90 min and then, where indicated, incubated with 100 μM NSC 228155 or CN 009543V or 150 ng/ml EGF or vehicle (0.2% DMSO) for 15 min.Proteins were blotted to nitrocellulose membrane and analyzed with biotinylated anti-pTyr P100, anti-pEGFR Y1068 and anti-EGFR (epitope in cytoplasmic region) antibodies. The phospho-specific antibodies were anti-phospho-Shc (Tyr239/240), anti-phospho-p44/42 MAPK (ERK1/2) (Thr202/Tyr204), anti-phospho-c-CBL (Tyr774), and anti-Gab1 (Tyr627). The signal intensity of the α-tubulin band was quantitatively evaluated and used as the loading control of protein samples.