CASP8 and neoplasm: FIS induces apoptosis in various tumor cells by, for example, inhibiting cyclooxygenase-2, inhibiting the Wnt/EGFR/NF-κB pathway, activating the caspase-3 cascade, activating the caspase-3 and Ca2+ dependent endonuclease, and activating the caspase-8/caspase-3 dependent pathway via ERK1/2.