title: Acetaminophen induces human neuroblastoma cell death through NFKB activation.
abstract: Neuroblastoma resistance to apoptosis may contribute to the aggressive behavior of this tumor. Therefore, it would be relevant to activate endogenous cellular death mechanisms as a way to improve neuroblastoma therapy. We used the neuroblastoma SH-SY5Y cell line as a model to study the mechanisms involved in acetaminophen (AAP)-mediated toxicity by measuring CYP2E1 enzymatic activity, NFkB p65 subunit activation and translocation to the nucleus, Bax accumulation into the mitochondria, cytochrome c release and caspase activation. AAP activates the intrinsic death pathway in the SH-SY5Y human neuroblastoma cell line. AAP metabolism is partially responsible for this activation, because blockade of the cytochrome CYP2E1 significantly reduced but did not totally prevent, AAP-induced SH-SY5Y cell death. AAP also induced NFkB p65 activation by phosphorylation and its translocation to the nucleus, where NFkB p65 increased IL-1β production. This increase contributed to neuroblastoma cell death through a mechanism involving Bax accumulation into the mitochondria, cytochrome c release and caspase3 activation. Blockade of NFkB translocation to the nucleus by the peptide SN50 prevented AAP-mediated cell death and IL-1β production. Moreover, overexpression of the antiapoptotic protein Bcl-x(L) did not decrease AAP-mediated IL-1β production, but prevented both AAP and IL-1β-mediated cell death. We also confirmed the AAP toxic actions on SK-N-MC neuroepithelioma and U87MG glioblastoma cell lines. The results presented here suggest that AAP activates the intrinsic death pathway in neuroblastoma cells through a mechanism involving NFkB and IL-1β.
authors.affiliation: Unidad Asociada Neurodeath, UCLM-CSIC, Universidad de Castilla-La Mancha, Albacete, Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Posadas
authors.forename: Pablo
authors.initials: P
authors.lastname: Santos
authors.forename: Valentín
authors.initials: V
authors.lastname: Ceña
mesh_terms: D000082:Acetaminophen / Q000494:pharmacology* / Q000627:therapeutic use; D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D000704:Analysis of Variance; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects*; D045744:Cell Line, Tumor; D019392:Cytochrome P-450 CYP2E1 / Q000378:metabolism; D006801:Humans; D009447:Neuroblastoma / Q000188:drug therapy*; D010455:Peptides / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D051996:Transcription Factor RelA / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: C494826:BAX protein, human; D010455:Peptides; D017382:Reactive Oxygen Species; C118258:SN50 peptide; D051996:Transcription Factor RelA; D051028:bcl-2-Associated X Protein; D000082:Acetaminophen; D019392:Cytochrome P-450 CYP2E1; D053148:Caspase 3