Schematic of DcR3-induced DC apoptosis. DcR3 binds to HSPG to activate PKC-δ and subsequently JNK. Activation of JNK up-regulates DR5 expression to induce ligand-independent activation of the downstream apoptotic signaling pathway via formation of DR5 DISC. The upstream caspase-2 and caspase-8 cleave Bid, which in turn disrupts the mitochondrial membrane potential and activates caspase-3 to induce DC apoptosis.