title: HDAC inhibitors with different gene regulation activities depend on the mitochondrial pathway for the sensitization of leukemic T cells to TRAIL-induced apoptosis.
abstract: Epigenetic modifications commonly associated with tumor development, such as histone deacetylation, may influence the resistance of some tumor cells to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) by regulating gene transcription of components of the TRAIL signalling pathway. In the present study we have analyzed the effect of six different histone deacetylase inhibitors (HDACi), belonging to the four classic structural families, on TRAIL-induced apoptosis in leukemic T cell lines. Non-toxic and functional doses of all HDACi but apicidin, similarly sensitized different leukemic T cell lines to TRAIL-induced apoptosis, while they showed no effect on the resistance of normal T lymphocytes. Sensitizing doses of vorinostat, valproic acid, sodium butyrate and MS-275 regulated the expression of TRAIL-R2, c-FLIP and Apaf-1 in leukemic cells while TSA modulated only the expression of Apaf-1. The synergistic effect of all HDACi and TRAIL was inhibited in Bcl-2-overexpressing leukemic T cells. Thus, different HDACi may affect the expression of different TRAIL-related genes, but regulation of the mitochondrial pathway seems to be essential for the TRAIL sensitizing effect of HDACi in leukemic T cells. Overall, HDACi represent a promising and safe strategy in combination with TRAIL for treatment of T-cell leukaemia.
authors.affiliation: IBIMER, Universidad de Granada, Centro de Investigación Biomédica, Granada, Spain.
authors.forename: J C
authors.initials: JC
authors.lastname: Morales
authors.forename: M J
authors.initials: MJ
authors.lastname: Ruiz-Magaña
authors.forename: D
authors.initials: D
authors.lastname: Carranza
authors.forename: G
authors.initials: G
authors.lastname: Ortiz-Ferrón
authors.forename: C
authors.initials: C
authors.lastname: Ruiz-Ruiz
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053477:Apoptotic Protease-Activating Factor 1 / Q000378:metabolism; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects*; D056572:Histone Deacetylase Inhibitors / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D019169:Jurkat Cells; D015458:Leukemia, T-Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D015394:Molecular Structure; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D013329:Structure-Activity Relationship; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000494:pharmacology
chemical_list: C506592:APAF1 protein, human; D053477:Apoptotic Protease-Activating Factor 1; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; C506386:CFLAR protein, human; D056572:Histone Deacetylase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D011994:Recombinant Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human