Epidermal growth factor receptor modulation of radiation response: preclinical and clinical development.

Approximately two thirds of all human solid tumors derive from epithelial tissues. The epidermal growth factor receptor (EGFR) serves as an important regulator of cellular growth in epithelial tumors. A spectrum of new anticancer agents have been specifically designed to target the EGFR in an effort to inhibit malignant growth. Although several of these new drugs show single-agent activity in early clinical trials, the predominant growth effect of EGFR signaling inhibition is cytostatic. However, the interaction of EGFR inhibition combined with conventional cytotoxic therapies (radiation and chemotherapy) is more potent, and shows great promise in the treatment of a variety of solid tumors that overexpress this receptor. This report focuses primarily on the capacity of EGFR inhibitors to modulate cellular and overall tumor response to ionizing radiation. Copyright 2002, Elsevier Science (USA). All rights reserved.