title: Synergistic induction of apoptosis in murine hepatoma Hepa1-6 cells by IFN-gamma and TNF-alpha.
abstract: In this study, we examined the susceptibility of murine hepatoma Hepa1-6 cells to undergo IFN-gamma- and/or TNF-alpha-induced apoptosis. IFN-gamma or TNF-alpha alone had no demonstrable cytotoxic effects, whereas IFN-gamma and TNF-alpha in combination induced apoptosis drastically in Hepa1-6 cells. During this apoptosis, an increase in caspase-3- and -8-like protease activities and activation of caspase-3, identified by the appearance of its p17 fragment, were observed. Moreover, the cytotoxic induction and caspase-3 activation were effectively inhibited by Z-Asp-CH(2)-DCB (Z-Asp), a caspase inhibitor. Further, an elevation of cytochrome c in the cytosol, in a parallel to activation of caspase-3, was observed in a time-dependent manner. Concurrently, up-regulation of caspase-11 gene expression and processing of procaspase-11 were detected during this apoptosis. These results suggest that the caspase-3 activation, the release of cytochrome c from mitochondria, and increased caspase-11 gene expression involve in synergistic induction of apoptosis in Hepa1-6 cells by IFN-gamma and TNF-alpha.
authors.affiliation: Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sasagawa
authors.forename: M
authors.initials: M
authors.lastname: Hlaing
authors.forename: T
authors.initials: T
authors.lastname: Akaike
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D061945:Caspase Inhibitors; D020169:Caspases / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D053471:Caspases, Initiator; D003574:Cytochrome c Group / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004357:Drug Synergism; D004789:Enzyme Activation / Q000187:drug effects; D004790:Enzyme Induction / Q000187:drug effects; D004792:Enzyme Precursors / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology*; D008113:Liver Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D061945:Caspase Inhibitors; D003574:Cytochrome c Group; D004792:Enzyme Precursors; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; C505409:Casp3 protein, mouse; C101136:Casp4 protein, mouse; C505526:Casp8 protein, mouse; C506434:Casp9 protein, mouse; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases; D053471:Caspases, Initiator