TNF and cancer: Various studies reported targeting both the mitochondrial (intrinsic) pathway and the extrinsic pathways via death receptors on the cell surface by many anti-cancer drugs.36-38 The granule exocytosis pathway is an additional pathway that involves natural killer (NK) and T-cell-mediated killing of target cells.37 The extrinsic apoptotic pathway triggers apoptosis by the binding of ligands (namely, first apoptosis signal ligand, tumor necrosis factor, and tumour necrosis factor-related apoptosis-inducing ligand) to their death receptors.39 Apoptosis is also mediated by caspases.