EGF and hepatocellular carcinoma: In this study, we have shown that seven HCC-derived EGFR mutants (K757E, N808S, R831C, V897A, P937L, T940A, and M947T) identified by our previous study [24] are functioning, EGF-dependent, EGFRs; cells harboring six of the seven mutants could generate some level of EGFR tyrosine phosphorylation in the absence of EGF, indicating some constitutive kinase activity, but all of the seven mutants remain primarily EGF-dependent.