Epidermal growth factor receptor (EGFR) plays an important role in cell-cycle regulation, proliferation, differentiation, and surviving of epithelial tissues. Aberrant overexpression of EGFR can initiate uncontrolled cell proliferation with subsequent formation of epithelial precancerous or malignant lesions.
Correlation between EGFR overexpression and increased resistance of tumor tissues to ionizing radiation has been described by many authors.