Treatment with 5-Aza-2'-Deoxycytidine Induces Expression of NY-ESO-1 and Facilitates Cytotoxic T Lymphocyte-Mediated Tumor Cell Killing

Abstract

BackgroundNY-ESO-1 belongs to the cancer/testis antigen (CTA) family and represents an attractive target for cancer immunotherapy. Its expression is induced in a variety of solid tumors via DNA demethylation of the promoter of CpG islands. However, NY-ESO-1 expression is usually very low or absent in some tumors such as breast cancer or multiple myeloma. Therefore, we established an optimized in vitro treatment protocol for up-regulation of NY-ESO-1 expression by tumor cells using the hypomethylating agent 5-aza-2'-deoxycytidine (DAC).Methodology/Principal FindingsWe demonstrated de novo induction of NY-ESO-1 in MCF7 breast cancer cells and significantly increased expression in U266 multiple myeloma cells. This effect was time- and dose-dependent with the highest expression of NY-ESO-1 mRNA achieved by the incubation of 10 μM DAC for 72 hours. NY-ESO-1 activation was also confirmed at the protein level as shown by Western blot, flow cytometry, and immunofluorescence staining. The detection and quantification of single NY-ESO-1 peptides presented at the tumor cell surface in the context of HLA-A*0201 molecules revealed an increase of 100% and 50% for MCF7 and U266 cells, respectively. Moreover, the enhanced expression of NY-ESO-1 derived peptides at the cell surface was accompanied by an increased specific lysis of MCF7 and U266 cells by HLA-A*0201/NY-ESO-1(157–165) peptide specific chimeric antigen receptor (CAR) CD8+ T cells. In addition, the killing activity of CAR T cells correlated with the secretion of higher IFN-gamma levels.Conclusions/SignificanceThese results indicate that NY-ESO-1 directed immunotherapy with specific CAR T cells might benefit from concomitant DAC treatment.

Differential expression of the TWEAK receptor Fn14 in IDH1 wild-type and mutant gliomas

“…This compound inhibits DNA methyltransferase leading to a reduction in DNA methylation [38]. We observed that Fn14 expression was up-regulated after 5-aza-dC treatment, but the effect was not strictly dose-dependent, consistent with a previous report examining 5-aza-dC activity on antigen presentation in breast cancer cells [48]. Our results suggest that the low level of Fn14 protein expression noted in both IDH1 mutant-overexpressing cells and IDH1 mutant tumors may be due, at least in part, to transcriptional repression by an epigenetic mechanism.…”

Correlation between methylation of the E-Cadherin gene and malignancy of prostate cancer

“…Such differences might be caused by different promoter regions or tissues selected or variability in test methods. 5-Aza-CdR is a methyltransferase inhibitor that can restore gene expression by demethylation (Klar et al, 2015). A previous study found restoration of E-Cadherin expression in a prostate cancer cell line after treatment with 5-Aza-CdR (Li et al, 2001), further suggesting the regulation of E-Cadherin expression by promoter methylation.…”

Acquired resistance during adoptive cell therapy by transcriptional silencing of immunogenic antigens

“…31 They function as DNA methyltransferase inhibitors (DNMTis), causing hypomethylation of DNA. Treatment of tumor cells with DNMTis can re-activate hypermethylated tumor suppressor genes, increase tumor cell immunogenicity by re-activating cancer testis and differentiation antigens, [32][33][34][35][36] and increase antigen presentation and MHC class I expression. 37 Recent studies suggest that DNMTis can induce a sustained interferon response in cancer cells by activating retroviral encoded double-stranded RNA.…”