The role of executioner caspases in cancer formation and maintenance

Caspases are proteases that are responsible for the initiation and execution of cell death pathways in developmental, inflammatory and pharmacological paradigms. Caspase activity is required for the execution of apoptotic cell death through the proteolytic cleavage of approximately one thousand substrates that result in the apoptotic phenotype. Impaired executioner caspase activity leads to delayed cell death and persistence of damaged cells that may impact overall organismal health. This is especially true in the case of cancer, impaired executioner caspase activity prevents execution of cell death and cells persist potentially leading to the formation or maintenance of tumors or lack of responsiveness to chemotherapeutic agents. Impairment of executioner activity can arise due to alterations in caspase expression, mutation in the caspase or alterations in caspase regulators. Here the human executioner caspases will be considered with specific focus on how expression and activity of caspase-3, -6, and -7 are altered in cancer.