From the Molecule to the Clinic — Inhibiting HER2 to Treat Breast Cancer

Much of the fundamental cancer research of the past two decades has focused on identifying the molecular and genetic changes that cause malignant transformation. These abnormalities can be attractive targets for the development of anticancer treatments. The family of epidermal growth factor–receptor tyrosine kinases, which includes epidermal growth factor receptor (EGFR, or ErbB-1), HER2 (ErbB-2), ErbB-3, and ErbB-4, has attracted considerable interest because many epithelial tumors, including breast cancer, express excess amounts of these proteins, particularly EGFR and HER2. In this issue of the Journal, Slamon et al. present important results of a randomized trial of a monoclonal antibody against . . .