title: Synergistic induction of NY-ESO-1 antigen expression by a novel histone deacetylase inhibitor, valproic acid, with 5-aza-2'-deoxycytidine in glioma cells.
abstract: NY-ESO-1, one of the most immunogenic cancer/testis antigens, provides attractive targets for cancer immunotherapy. NY-ESO-1 has been demonstrated to be expressed in a range of solid tumors via DNA demethylation and/or histone modification; however, it has been rarely expressed in glioma. The reversibility of these epigenetic aberrations is potentially attractive for glioma treatment with DNA-methyltransferase inhibitors (DNMTi) and histone deacetylase inhibitors (HDACi), leading to reactivation of silenced genes. We previously demonstrated de novo induction of NY-ESO-1 in glioma cells by DNMTi. In this study, we show that an anticonvulsant, i.e., valproic acid (VPA), also acting as an HDACi, enhances induction of NY-ESO-1 in synergy with DNMTi. Chromatin assays demonstrated that combination of DNMTi and VPA elicited significant DNA demethylation, histone H3 Lys9 demethylation, and acetylation. These findings not only shed light on an epigenetic immunotherapy, but also suggest that the silencing of NY-ESO-1 is mediated by histone modification.
authors.affiliation: Department of Neurosurgery, Nagoya University School of Medicine, Showa-ku, Nagoya, 466-8550, Japan.
authors.forename: Sachie
authors.initials: S
authors.lastname: Oi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Natsume
authors.forename: Motokazu
authors.initials: M
authors.lastname: Ito
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kondo
authors.forename: Shinji
authors.initials: S
authors.lastname: Shimato
authors.forename: Yuka
authors.initials: Y
authors.lastname: Maeda
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Saito
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Wakabayashi
mesh_terms: D000951:Antigens, Neoplasm / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D001374:Azacitidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000378:metabolism*; D045744:Cell Line, Tumor; D019175:DNA Methylation; D000077209:Decitabine; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000008:administration & dosage*; D015870:Gene Expression / Q000187:drug effects; D005910:Glioma / Q000378:metabolism*; D056572:Histone Deacetylase Inhibitors; D006657:Histones / Q000187:drug effects; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D008565:Membrane Proteins / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014635:Valproic Acid / Q000008:administration & dosage*
chemical_list: D000951:Antigens, Neoplasm; C104948:CTAG1B protein, human; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D006657:Histones; D008565:Membrane Proteins; D014635:Valproic Acid; D000077209:Decitabine; D001374:Azacitidine