The cells harboring HCC-derived EGFR mutants are erlotinib-resistant, as erlotinib up to high concentration could only induce partial inhibition of EGFR phosphorylation, and partial or no inhibition of AKT and ERK phosphorylation, and partial induction of apoptosis and autophagy. The gene discussed is EGFR; the disease is hepatocellular carcinoma.