The DNA demethylating agent 5-aza-2'-deoxycytidine activates NY-ESO-1 antigenicity in orthotopic human glioma.
Cancer/testis antigens (CTAs) are considered to be suitable targets for the immunotherapy of human malignancies. It has been demonstrated that in a variety of tumors, the expression of certain CTAs is activated via the demethylation of their promoter CpG islands. In our study, we have shown that while the composite expression of 13 CTAs in 30 human glioma specimens and newly established cell lines from the Japanese population was nearly imperceptible, the DNA-demethylating agent 5-aza-2'-deoxycytidine (5-aza-CdR) markedly reactivated CTA expression in glioma cells but not in normal human cells. We quantified the diminished methylation status of NY-ESO-1-one of the most immunogenic CTAs-following 5-aza-CdR treatment by using a novel Pyrosequencing technology and methylation-specific PCR. Microarray analysis revealed that 5-aza-CdR is capable of signaling the immune system, particularly, human leukocyte antigen (HLA) class I upregulation. (51)Cr-release cytotoxicity assays and cold target inhibition assays using NY-ESO-1-specific cytotoxic T lymphocyte (CTL) lines demonstrated the presentation of de novo NY-ESO-1 antigenic peptides on the cell surfaces. In an orthotopic xenograft model, the systemic administration of 5-aza-CdR resulted in a significant volume reduction of the transplanted tumors and prolonged the survival of the animals after the adoptive transfer of NY-ESO-1-specific CTLs. These results suggested that 5-aza-CdR induces the expression of epigenetically silenced CTAs in poorly immunogenic gliomas and thereby presents a new strategy for tumor immunotherapy targeting 5-aza-CdR-induced CTAs.
Natsume
Atsushi
A
Department of Neurosurgery, Nagoya University School of Medicine, Nagoya, Japan. anatsume@med.nagoya-u.ac.jp
Wakabayashi
Toshihiko
T
Tsujimura
Kunio
K
Shimato
Shinji
S
Ito
Motokazu
M
Kuzushima
Kiyotaka
K
Kondo
Yutaka
Y
Sekido
Yoshitaka
Y
Kawatsura
Hitomi
H
Narita
Yuji
Y
Yoshida
Jun
J
D019264:Adoptive Transfer; D000704:Analysis of Variance; D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D000964:Antimetabolites, Antineoplastic / Q000276:immunology / Q000494:pharmacology*; D044466:Asian People; D001374:Azacitidine / Q000031:analogs & derivatives* / Q000276:immunology / Q000494:pharmacology; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000188:drug therapy / Q000276:immunology; D002874:Chromosome Mapping; D018899:CpG Islands; D019175:DNA Methylation / Q000187:drug effects*; D000077209:Decitabine; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000188:drug therapy* / Q000276:immunology* / Q000401:mortality; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008565:Membrane Proteins / Q000276:immunology*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D046228:Microarray Analysis; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013602:T-Lymphocytes, Cytotoxic; D013737:Testis; D014183:Transplantation, Heterologous; D015854:Up-Regulation
D000951:Antigens, Neoplasm; D000964:Antimetabolites, Antineoplastic; C104948:CTAG1B protein, human; D015395:Histocompatibility Antigens Class I; D008565:Membrane Proteins; D000077209:Decitabine; D001374:Azacitidine