title: Signaling and function of caspase and c-jun N-terminal kinase in cisplatin-induced apoptosis.
abstract: Caspases and c-Jun N-terminal kinase (JNK) are activated in tumor cells during induction of apoptosis. We investigated the signaling cascade and function of these enzymes in cisplatin-induced apoptosis. Treatment of Jurkat T-cells with cisplatin induced cell death with DNA fragmentation and activation of caspase and JNK. Bcl-2 overexpression suppressed activation of both enzymes, whereas p35 and CrmA inhibited only the DEVDase (caspase-3-like) activity, indicating that the activation of these enzymes may be differentially regulated. Cisplatin induced apoptosis with the cytochrome c release and caspase-3 activation in both wild-type and caspase-8-deficient JB-6 cells, while the Fas antibody induced these apoptotic events only in wild-type cells. This indicates that caspase-8 activation is required for Fas-mediated apoptosis, but not cisplatin-induced cell death. On the other hand, cisplatin induced the JNK activation in both the wild-type and JB-6 cells, and the caspase-3 inhibitor Z-DEVD-fmk did not inhibit this activation. The JNK overexpression resulted in a higher JNK activity, AP-1 DNA binding activity, and metallothionein expression than the empty vector-transfected cells following cisplatin treatment. It also partially protected the cells from cisplatin-induced apoptosis by decreasing DEVDase activity. These data suggest that the cisplatin-induced apoptotic signal is initiated by the caspase-8-independent cytochrome c release, and the JNK activation protects cells from cisplatin-induced apoptosis via the metallothionein expression.
authors.affiliation: Vascular System Research Center, Kangwon National University, Chunchon, Korea.
authors.forename: Myoung-Sook
authors.initials: MS
authors.lastname: Koo
authors.forename: Young-Guen
authors.initials: YG
authors.lastname: Kwo
authors.forename: Joon-Hong
authors.initials: JH
authors.lastname: Park
authors.forename: Won-Jin
authors.initials: WJ
authors.lastname: Choi
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Billiar
authors.forename: Young-Myeong
authors.initials: YM
authors.lastname: Kim
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D002945:Cisplatin / Q000494:pharmacology*; D015853:Cysteine Proteinase Inhibitors / Q000378:metabolism; D053938:DNA Fragmentation; D004789:Enzyme Activation; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases; D019169:Jurkat Cells; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D011485:Protein Binding; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D015843:Serpins / Q000235:genetics / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D000970:Antineoplastic Agents; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2; D015843:Serpins; D018808:Transcription Factor AP-1; D014764:Viral Proteins; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D008668:Metallothionein; C074641:interleukin-1beta-converting enzyme inhibitor; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D020169:Caspases; D002945:Cisplatin