Combination of epidermal growth factor receptor targeted therapy with radiation therapy for malignant gliomas

Glioblastoma multiforme (GBM) are extremely aggressive brain tumors characterized by resistance to standard treatment modalities including surgery, radiation therapy and chemotherapy. While radiation therapy is the standard treatment after surgical resection, these tumors invariably recur and are associated with a uniformly dismal prognosis. Cytotoxic chemotherapy has failed to improve on the modest gains conferred by radiation therapy. Our understanding of the molecular events driving gliomagenesis has led to the recognition of frequent alterations in the epidermal growth factor receptor (EGFR) pathway, leading to increased aggressiveness and a poorer prognosis. Based on the importance of EGFR in the development of malignancy in multiple tumor types, several classes of novel therapeutic agents have been developed that specifically target EGFR. This review outlines the relevance of normal and aberrant EGFR signaling in the biology of gliomas, the strategies for inhibiting EGFR activity and the rationale for combining EGFR inhibitors with radiation therapy in the treatment of GBM.