Apoptosis, also called programmed cell death, is an essential process in development and disease. The signaling networks that carry out apoptosis is consists of a series of endoproteases called caspases which are synthesized as inactive zymogens. Caspses are grouped into two classes: initiator caspases and effector caspases. Initiator caspases are activated by the assembly of multi-protein complexes such as the death-inducing signaling complex (DISC) (1).