Fig. 4.

Distinct effects of EGFR inhibitors on EGFR phosphorylation in epithelial- and mesenchymal-like esophageal cells. Phosphorylated- and total-EGFR protein levels in epithelial-like esophageal cells (T-Epi and TE-11R) and mesenchymal-like esophageal cells (T-Mes and TE-8) treated with or without erlotinib or cetuximab for 24 h, determined by western blotting. Both erlotinib and cetuximab suppressed the phosphorylation of EGFR signaling in epithelial-like esophageal cells but not in mesenchymal-like esophageal cells