FIGURE 1.

EGFR increases K17 protein levels. A431 cells were growth factor-deprived prior to 100 ng/ml EGF treatment for the indicated time periods (A) or incubated with various concentrations of EGFR inhibitor Erlotinib for 2 h (B). Whole cell lysates were prepared in Triton lysis buffer, and immunoblotting was performed with antibodies against the indicated proteins. Anti-phosphotyrosine (PY) 4G10 antibody was used to show EGFR activity. K17 and GAPDH signal intensities were quantified using ImageJ software.