Figure 2.

Incorporation of a K1037Q mutation in an L+T EGFR background makes stable receptor more vulnerable to TKI-mediated degradation. A, CHO cells overexpressing either WT or different mutants of EGFR (as indicated) were treated with 3 μm erlotinib for 24 h. Cell lysates were then subjected to immunoblot analysis with the indicated antibodies. Erlotinib-induced EGFR downregulation was calculated by quantifying band intensities (arbitrary units) considering the untreated level as 1. B, CHO cells transfected with indicated EGFR mutants were treated with erlotinib as described for panel A followed by immunoprecipitation using EGFR antibody and immunoblotting with the indicated antibodies.