With EGF treatment, cells harboring HCC-derived EGFR mutants displayed increased levels of pEGFR at Y869 in the range of 89–153%, and at Y1092 in the range of 40–86%, of the level in cells harboring T790M without EGF treatment, which was calibrated as 100%. The gene discussed is EGF; the disease is hepatocellular carcinoma.