Fig. 3.
EGFR tyrosine phosphorylation is regulated by reactive oxygen. (A) MDA-MB-468 cells were treated with 0.5 µM gefitinib for 30min and/or 50mM N-acetyl cysteine for the last 10 min as indicated. Cell lysates were immunoprecipitated using anti-EGFR antibodies and immunoblotted with anti-EGFR or anti-phosphotyrosine antibodies. (B) SUM149 cells were treated with 0.5 µM gefitinib and/or 5mM H2O2. Cell lysates were immunoprecipitated using anti-EGFR antibodies and immunoblotted with anti-EGFR or anti-phosphotyrosine antibodies. Control=vehicle control treated; gef=gefitinib treated; NAC=N-acetyl cysteine treated; IB=immunoblot; and IP=immunoprecipitation.