Figure 9.

Model of FADD-DD–induced apoptosis signaling in normal prostate epithelial cells. FADD-DD works through unidentified effectors to activate caspase 9 through a mitochondrial caspase activation pathway that is Bcl-xL sensitive. This leads to the activation of effector caspases, which cause cell death that is associated with membrane blebbing and cellular fragmentation. In addition, a serine protease pathway is activated that can be inhibited by AEBSF but not by Bcl-xL, which causes cell death that is associated with cell rounding and detachment. This pathway is not activated in prostate cancer cells because these cells possess defects in effector molecules that mediate the death domain signal.