Overview:

The epidermal growth factor receptor (EGFR) is a transmembrane tyrosine kinase. Known ligands of EGFR include EGF, TGFA/TGF-alpha, amphiregulin, epigen/EPGN, BTC/betacellulin, epiregulin/EREG and HBEGF/heparin-binding EGF. Ligand binding induces receptor homo- and hetero-dimerization and tyrosine autophosphorylation, which triggers downstream signaling events. The consequences of EFGR signaling include cell proliferation, differentiation, motility, and cell survival (1). Activation of EGFR triggers mitogenic signaling in gastrointestinal mucosa and EGFR upregulated in colon cancers and most neoplasms (2). EGFR stimulation also activates the ERK-signaling pathway in normal gastric epithelial and colon cancer cell lines. In contrast, selective inhibition of EGFR significantly reduces ERK2 activation, c-fos mRNA expression and cell proliferation. Mutations in EGFR are also implicated in specific forms of lung cancer.

References:

1. Wang K, et al: Epidermal growth factor receptor-deficient mice have delayed primary endochondral ossification because of defective osteoclast recruitment. J. Biol. Chem. 279: 53848-53856, 2004.

2. Kobayashi S, et al: EGFR mutation and resistance of non-small-cell lung cancer to gefitinib. New Eng. J. Med. 352: 786-792, 2005.