Caspase-9 has a vital role in neutralizing cells by initiating apoptotic death early in the development stage. It is necessary for caspase-9 to inhibit proliferative diseases through the consistent removal of irreparable cells in the life cycle. It regulates cell homeostasis through the cleavage of cellular proteins involved in apoptosis. Caspase-9 initiates cleavage in response to stresses that trigger the release of cytochrome c from mitochondria. It is activated when complexed with apoptotic protease activating factor 1 (APAF-1). The activated form of caspase-9 then initiates the caspase cascade. Caspase-9 also has a role in cytokine processing. However, caspase 1, 4 ,5, 11, 12, and 14 play a more active role in cytokine processing.