CASP8 and hepatocellular carcinoma: FLICE inhibitory protein (c-FLIP), a recently identified intracellular inhibitor of caspase-8 activation that can potentially inhibit death signaling mediated by various death receptors, like Fas, TNF-receptor (TNF-R), and TNF-related apoptosis-inducing ligand receptors (TRAIL-Rs) and by NFĸB activation, was found to be constitutively expressed in HCC cell lines and over-expressed in human HCC tissues.