Role of apoptosis in colon cancer biology, therapy, and prevention

Deregulation of apoptosis is a hallmark of human cancer and contributes to therapeutic resistance. Recent advances in cancer genomics reveal a myriad of alterations in key pathways that directly or indirectly increase tumor cell survival. This review will outline the pathways of apoptosis in mammalian cells, and highlight the common alterations of apoptosis regulators found in colon cancer, the role of apoptosis and underlying mechanisms in colon cancer treatment and prevention, including recent advances on investigational agents, such as kinase inhibitors, proteasome inhibitors, HSP90 inhibitors, BH3 mimetics, TRAIL, and IAP antagonists. Topics will also include novel concepts, as well as opportunities and challenges for drug discovery and combination therapy by exploring cancer-specific genetic defects, and therefore selective induction of apoptosis in cancer cells. Although the emphasis is on colon cancer, the main theme and many of the aspects are applicable to other solid tumors.