CASP9 and liver cancer: In order to reaffirm the involvement of caspases in Far-C-instigated cytotoxicity in HepG2 cells, MTT assay was carried out in human liver cancer HepG2 cells pretreated with Z-LEHD-FMK and ZDEVD-FMK (50 μM each for 2 h) which are specific inhibitors of caspase-9 and caspase-3, respectively.