Primers on molecular pathways--caspase pathway.

Apoptosis, or programmed cell death, is a physiological process of cellular autodestruction, or cell suicide. This process is strictly controlled in response to integrity of pro-death signaling and plays critical roles in development, maintenance of homeostasis and host defense in multicellular organisms. As pancreatologists, apoptosis plays a central role in the pancreas and its disease states, from diabetes to pancreatitis to pancreatic cancer. In pancreatic beta-cells, apoptotic cell death is involved in the pathogenesis of diabetes, as signals from death receptors and DNA damage have been widely accepted as being triggers of apoptosis in beta-cells. During acute pancreatitis, this common clinical condition is of variable severity in which some patients experience mild, self-limited attacks while others manifest a severe, highly morbid, and frequently lethal attack. However, recent research in this area has demonstrated the importance of acinar cell death in the form of apoptosis and necrosis as a determinant of pancreatitis severity. In pancreatic cancer, various survival mechanisms have been shown to act in the prevention of cell death to result in promotion of tumor growth and metastasis. Thus, resistance of pancreatic cancer to apoptosis is the key factor preventing responses to therapies. Thus, it is for these reasons that in the current 'Primers on Molecular Pathways,' we take a closer look at the pathway cascade that is triggered during apoptosis.