FASLG and neoplasm: The main pathways of killing are: a) causing apoptosis of target cells through the release of lysozyme in intercellular contacts; b) acting on the target cell-expressed receptor Fas via Fas ligand (Fas-L), leading to apoptosis of target cells through a cysteine-dependent pathway; and c) indirectly inducing death of peripheral tumor cells through the secretion of cytokines (22, 23).