Sequential 5-Aza-2’-deoxycytidine-Depsipeptide FR901228 Treatment Induces Apoptosis Preferentially in Cancer Cells and Facilitates Their Recognition by Cytolytic T Lymphocytes Specific for NY-ESO-1

Abstract

Global alterations in chromatin structure profoundly influence gene expression in thoracic neoplasms, silencing tumor suppressors while facilitating the expression of various cancer testis antigens such as NY-ESO-1. Although recent studies have shown that histone deacetylase inhibitors can potentiate tumor suppressor gene induction mediated by demethylating agents in cancer cells, the ability of these agents to augment cancer testis antigen expression have not been fully defined. The authors designed the current study to determine whether the histone deacetylase inhibitor, depsipeptide FR901228 (DP), could enhance NY-ESO-1 induction mediated by the DNA demethylating agent 5-Aza-2'-deoxycytidine (DAC) in cell lines established primarily from thoracic cancers. Quantitative reverse-transcriptase polymerase chain reaction analysis revealed that, under exposure conditions potentially achievable in clinical settings, DAC dramatically induced NY-ESO-1 expression in cultured cancer lines. DP alone mediated negligible target gene induction but significantly augmented DAC-mediated induction of NY-ESO-1. After DAC or sequential DAC-DP treatment, HLA-A*0201 cancer cells were recognized by an HLA-A*0201 CTL specific for NY-ESO-1. Although sequential DAC/DP exposure did not uniformly enhance immune recognition of target cells compared with DAC alone, this treatment mediated profound induction of apoptosis in cancer cells but not normal human bronchial epithelia. The apoptotic effects of DAC, DP, or sequential DAC-DP did not correlate in an obvious manner with histology, or the magnitude of NY-ESO-1 induction in cancer cells. Although the mechanisms have not been fully defined, sequential DAC-DP treatment may be a novel strategy to augment antitumor immunity in cancer patients.

Primary Human Lymphocytes Transduced with NY-ESO-1 Antigen-Specific TCR Genes Recognize and Kill Diverse Human Tumor Cell Lines

“…Additionally, it may be possible to up-regulate NY-ESO-1 expression in cancer patients by treatment with drugs that induce DNA demethylation (38,39). Finally, we have identified MHC class II-restricted NY-ESO-1 TCR epitopes (22,40,41), and we are currently attempting to simultaneously engineer a population of T cells with both class Iand class II-restricted TCRs.…”

Epigenetic regulation of X-linked cancer/germline antigen genes by DNMT1 and DNMT3b

“…Consistent with our previous microarray study (Karpf et al, 2004), we observed that treatment with DAC, a classical DNMT inhibitor (Christman, 2002), elicited robust dose-dependent induction of CG-X antigen genes in the colorectal cancer cell lines HCT116 and RKO (Supplemental Figure 1a-c). Based on previous reports (Cameron et al, 1999;Weiser et al, 2001), we investigated whether treatment with the histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) enhances the ability of DAC to activate CG-X antigen gene expression. TSA treatment slightly augmented DAC-mediated induction of CG-X antigen expression (Supplemental Figure 1a-c), as did TSA treatment alone, in both cell types (Supplemental Figure 1b and activation of CG-X antigen gene expression is associated with promoter methylation changes, we examined CG-X antigen gene promoter methylation before and after DAC treatment using methylation-specific PCR (MSP) (Herman et al, 1996).…”

“…The first evidence of a role for DNA methylation in the regulation of CG-X antigen expression was provided by experiments using the DNA methyltransferase inhibitor 5-aza-2 0 -deoxycytidine (DAC) (Weber et al, 1994). Subsequently, the expression of several CG-X antigen genes was shown to inversely correlate with promoter methylation, and to be responsive to activation by DNA methyltransferase inhibitors (De Smet et al, 1996Weiser et al, 2001;Sigalotti et al, 2002;Karpf et al, 2004). CG-X gene expression has also been postulated, based on data in human melanoma cell lines, to be associated with global genomic DNA hypomethylation (De Smet et al, 1996).…”

Phase I Trial of Sequential Low-Dose 5-Aza-2′-Deoxycytidine Plus High-Dose Intravenous Bolus Interleukin-2 in Patients with Melanoma or Renal Cell Carcinoma

“…Based on duplicates of each condition (pre and post treatment), a threshold of 2-fold change in expression relative to control expression of each gene was reported as the ratio of the value obtained for each condition relative to control conditions after data normalization. 7 Statistical methods. Mean changes across time on DNA methylation and HbF from baseline to each follow-up time point were tested with the one-sample (dependent) t test and the one-sample nonparametric test.…”