Deglycosylated bleomycin induces apoptosis in lymphorna cell via c-jun NH2-terminal kinase but not reactive oxygen species
Fiche publication
Date publication
novembre 2007
Auteurs
Membres identifiés du Cancéropôle Est :
Pr BETTAIEB Ali, Dr MICHEAU Olivier
Tous les auteurs :
Brahim S, Prevotat L, Yatouji S, Merino D, Cortier M, Rebe C, Micheau O, Kenani A, Bettaieb A
Lien Pubmed
Résumé
Bleomycin (BLM) has demonstrated potent activity in treating malignant lymphomas but its therapeutic efficacy is hampered by induction of lung fibrosis. This side effect is related to the ability of the drug to generate reactive oxygen species in lung cells. In the present study, we evaluated the consequences of deglycosylation of BLM in term of cytotoxic activity and generation of reactive oxygen species. When tested on U937 human lymphoma cells, both compounds generated a typical apoptotic phenotype. Cell death induction was associated with Bax oligomerization, dissipation of the mitochondrial membrane potential, release of cytochrome c, caspase activation, chromatin condensation and internucleosomal degradation. Whereas both reactive oxygen species and c-jun NH2-terminal kinase JNK) inhibitors prevented BLM-induced U937 cell death, only JNK inhibition prevented deglycosylated BLM-mediated cell death. Both compounds induced clustering of TRAIL receptors (DR4 and DR5) and Fas at the cell surface but neither a chimeric soluble DR5 receptor that inhibits TRAIL-induced cell death nor a dominant negative version of the adaptor molecule Fas-associated death domain prevented BLM-induced cytotoxicity. These observations indicate that deglycosylation of BLM does not impair the ability of the drug to trigger cell death through activation of the intrinsic pathway but prevents induction of reactive oxygen species. This observation suggests that deglycosylated BLM could exhibit less toxic side effects and could warrant its use in clinic. (c) 2007 Elsevier Inc. All rights reserved.
Référence
Biochem Pharmacol. 2007 Nov 15;74(10):1445-55