Emerging Receptor Tyrosine Kinase Drug Targets: Implications for Antibody-Based Therapies for Oncology and Immunologic Disorders.

Protein kinases play a critical regulatory role in essentially every aspect of cell biology. Of the 518 known kinases, the most successful class for drug targeting is the receptor tyrosine kinase (RTK) family consisting of 58 distinct and diverse members. RTKs regulate a broad range of cellular functions, including proliferation, differentiation, survival, and apoptosis and have been intensively studied in development and cancer. Targeting of RTKs has resulted in many marketed small molecule and antibody-based drugs in a number of different solid tumors and hematological malignancies, and more recently in inflammatory diseases such as idiopathic pulmonary fibrosis. In this review, we discuss some of the RTKs in cancer in which drugs targeting the ErbB family (EGFR, HER2, and ErbB3) and KIT have had meaningful clinical benefit to cancer patients, RTKs' emerging role in regulating innate immunity, and the potential to explore targeting RTKs outside of oncology.