Transforming growth factor-beta: A target for cancer therapy

Transforming growth factor-beta (TGF-β) is a pleiotropic growth factor that regulates cell growth and differentiation, apoptosis, cell motility, extracellular matrix production, angiogenesis, and cellular immune responses. TGF-β demonstrates paradoxical action whereby it can function to suppress early tumorigenesis; however, it can also facilitate malignant transformation and stimulate tumor growth by manipulating a more hospitable environment for tumor invasion and the development of metastases. Given the integral role of TGF-β in transformation and cancer progression, various components of the TGF-β signaling pathway offer potentially attractive therapeutic targets for cancer treatment. This review focuses on the role of TGF-β in cancer and discusses both small and large molecule drugs currently in development that target TGF-β, its receptor and important down stream steps along its signaling pathway.