CASP8 and neoplasm: Activation of VEGFR2 by VEGF-A or VEGF-B causes phosphorylation of c-Src and has been linked to increased permeability by altering adherens junction formation, VE-cadherin.33, 43 c-Src has been shown to inhibit Fas-induced caspase-8 activation by phosphorylation at Tyr380.44 Further studies are required to determine if RIPK1 and RIPK3 alter tumor cell extravasation as a complex with or without caspase-8 involvement or if these proteins regulate different pathways to result in vascular permeability.