among the early discoveries disclosing this relationship are the finding of transforming growth factor alpha (TGFα) as part of an autocrine loop leading to cell malignant transformation (Sporn and Todaro, 1980); the high sequence homology found between the EGFR and the retroviral oncogenic protein called v-ERBB (Downward et al., 1984); the increased EGFR expression observed in human squamous cell lung cancers (Hendler and Ozanne, 1984), and the subsequent finding of EGFR aberrant expression and gene amplification in a human tumor cell line (Ullrich et al., 1984). Here, EGFR is linked to squamous cell lung carcinoma.