title: TRAIL activates a caspase 9/7-dependent pathway in caspase 8/10-defective SK-N-SH neuroblastoma cells with two functional end points: induction of apoptosis and PGE2 release.
abstract: Most neuroblastoma cell lines do not express apical caspases 8 and 10, which play a key role in mediating tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) cytotoxicity in a variety of malignant cell types. In this study, we demonstrated that TRAIL induced a moderate but significant increase of apoptosis in the caspase 8/10-deficient SK-N-SH neuroblastoma cell line, through activation of a novel caspase 9/7 pathway. Concomitant to the induction of apoptosis, TRAIL also promoted a significant increase of prostaglandin E2 (PGE2) release by SK-N-SH cells. Moreover, coadministration of TRAIL plus indomethacin, a pharmacological inhibitor of cyclooxygenase (COX), showed an additive effect on SK-N-SH cell death. In spite of the ability of TRAIL to promote the phosphorylation of both ERK1/2 and p38/MAPK, which have been involved in the control of COX expression/activity, neither PD98059 nor SB203580, pharmacological inhibitors of the ERK1/2 and p38/MAPK pathways, respectively, affected either PGE2 production or apoptosis induced by TRAIL. Finally, both induction of apoptosis and PGE2 release were completely abrogated by the broad caspase inhibitor z-VAD-fmk, suggesting that both biologic end points were regulated in SK-N-SH cells through a caspase 9/7-dependent pathway.
authors.affiliation: Department of Human Normal Morphology, University of Trieste, Trieste 34138, Italy. zauli@units.it
authors.forename: Giorgio
authors.initials: G
authors.lastname: Zauli
authors.forename: Daniela
authors.initials: D
authors.lastname: Milani
authors.forename: Erika
authors.initials: E
authors.lastname: Rimondi
authors.forename: Giovanna
authors.initials: G
authors.lastname: Baldini
authors.forename: Vanessa
authors.initials: V
authors.lastname: Nicolin
authors.forename: Vittorio
authors.initials: V
authors.lastname: Grill
authors.forename: Paola
authors.initials: P
authors.lastname: Secchiero
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D015153:Blotting, Western; D053455:Caspase 10; D053179:Caspase 7; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism*; D045744:Cell Line, Tumor; D015232:Dinoprostone / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D020935:MAP Kinase Signaling System; D008562:Membrane Glycoproteins / Q000378:metabolism*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009447:Neuroblastoma / Q000378:metabolism*; D010641:Phenotype; D010766:Phosphorylation; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D020033:Protein Isoforms; D011725:Pyridines / Q000494:pharmacology; D053221:TNF-Related Apoptosis-Inducing Ligand; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D051017:Apoptosis Regulatory Proteins; D004791:Enzyme Inhibitors; D005419:Flavonoids; D007093:Imidazoles; D008562:Membrane Glycoproteins; D020033:Protein Isoforms; D011725:Pyridines; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D011451:Prostaglandin-Endoperoxide Synthases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C505520:CASP7 protein, human; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053455:Caspase 10; D053179:Caspase 7; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases; C506438:CASP10 protein, human; D015232:Dinoprostone; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one