Targeted Therapeutics in Cancer Treatment

This chapter discusses how various cellular processes regulating the oncogenesis can be targeted by small molecule inhibitors. It focuses on the challenges of incorporating the small molecule inhibitors into the reserve of general oncology practice, either as single agents or in combination with other small molecule inhibitors or cytotoxic chemotherapy. Modern chemotherapy targets discrete molecular signaling pathways to achieve an anticancer effect. The monoclonal antibodies targeting-the ligand as well as the extracellular domains of the transmembrane receptors, and the small molecules-designed to inhibit the kinase function of the intracellular signaling proteins have been developed to achieve clinical effects. These molecules improve efficacy while limiting toxicity. The efficacy of small molecule inhibitors depends on the relevance of the targeted signal to the oncogenesis of the tumor. Few solid tumors are dependent on a single pathway for oncogenesis. Therefore, it is more efficacious to inhibit the multiple targets with a single small molecule inhibitor.