FAS and cancer: This extrinsic apoptotic pathway depends on the external stimulation following the binding of extracellular death ligands, such as Fas ligand (FasL, CD95L, CD178, TNSF6), tumor necrosis factor-α (TNF-α, cachectin, TNFSF2) and/or TNF-related apoptosis-inducing ligand (TRAIL, CD253, APO-2L, TNFSF10), to their cognate death receptors Fas (CD95, APO-1, TNFRSF6), TNF-receptor 1 (TNF-R1, CD120a, TNFRSF1A), TRAIL-receptor 1 (TRAIL-R1, CD261, DR4, APO-2, TNFRSF10A), and/or TRAIL-R2 (CD262, DR5, TNFRSF10B), respectively, on the plasma membrane [1–3], which are promising targets in cancer [4].