Project description:Gene expression analysis of 5-aza-dC treated pancreatic cancer associated fibroblasts To identify genes silenced by methylation in pancreatic CAFs, we performed gene expression profiling on 5-aza-dC treated pancreatic cancer associated fibroblast cultures using Affymetrix Exon arrays. We analyzed 5 untreated and 5-aza-dC-treated pancreatic cancer associated fibroblast cultures using the Affymetrix Human Exon 1.0 ST platform. Gene expression levels were compared using Partek (version 6.3beta).
Project description:Gene expression analysis of 5-aza-dC treated pancreatic cancer associated fibroblasts To identify genes silenced by methylation in pancreatic CAFs, we performed gene expression profiling on 5-aza-dC treated pancreatic cancer associated fibroblast cultures using Affymetrix Exon arrays.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy that resists current treatments. To test epigenetic therapy against this cancer we used the DNA demethylating drug 5-aza-2’-deoxycytidine (DAC) in a KrasLSL-G12D; p53LSL-R270H/+; Pdx1-cre; Brca1flex2/flex2 (KPC-Brca1) mouse model of aggressive stroma-rich PDAC. In untreated tumors, we found globally decreased 5-methyl-cytosine (5mC) in malignant epithelial cells and in cancer-associated myofibroblasts (CAFs), and increased amounts of 5-hydroxymethyl-cytosine (5HmC) in CAFs, in progression from pancreatic intraepithelial neoplasia (PanIN) to PDAC. DAC further reduced DNA methylation and slowed PDAC progression, markedly extending survival in an early treatment protocol and significantly though transiently inhibiting tumor growth when initiated later, without adverse side effects. Escaping tumors contained areas of sarcomatoid transformation with disappearance of CAFs. Mixing-allografting experiments and proliferation indices showed that DAC efficacy was due to inhibition of both the malignant epithelial cells and the stromal CAFs. Expression profiling and immunohistochemistry highlighted DAC-induction of STAT1 in the tumors, and DAC plus gamma-interferon produced an additive anti-proliferative effect on PDAC cells. DAC induced strong expression of the testis antigen DAZL in CAFs. These data show that DAC is effective against PDAC in vivo and provide a rationale for future studies combining hypomethylating agents with cytokines and immunotherapy. Treatment of a short-term explant culture of cancer-associated fibroblasts (CAFs) from a KPC-Brca1 mouse pancreatic carcinoma, with 2 micromolar 5-aza-dC (decitabine; DAC) for 48 hours. The experiment includes 3 replicate plates untreated and 3 replicates treated.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy that resists current treatments. To test epigenetic therapy against this cancer we used the DNA demethylating drug 5-aza-2’-deoxycytidine (DAC) in a KrasLSL-G12D; p53LSL-R270H/+; Pdx1-cre; Brca1flex2/flex2 (KPC-Brca1) mouse model of aggressive stroma-rich PDAC. In untreated tumors, we found globally decreased 5-methyl-cytosine (5mC) in malignant epithelial cells and in cancer-associated myofibroblasts (CAFs), and increased amounts of 5-hydroxymethyl-cytosine (5HmC) in CAFs, in progression from pancreatic intraepithelial neoplasia (PanIN) to PDAC. DAC further reduced DNA methylation and slowed PDAC progression, markedly extending survival in an early treatment protocol and significantly though transiently inhibiting tumor growth when initiated later, without adverse side effects. Escaping tumors contained areas of sarcomatoid transformation with disappearance of CAFs. Mixing-allografting experiments and proliferation indices showed that DAC efficacy was due to inhibition of both the malignant epithelial cells and the stromal CAFs. Expression profiling and immunohistochemistry highlighted DAC-induction of STAT1 in the tumors, and DAC plus gamma-interferon produced an additive anti-proliferative effect on PDAC cells. DAC induced strong expression of the testis antigen DAZL in CAFs. These data show that DAC is effective against PDAC in vivo and provide a rationale for future studies combining hypomethylating agents with cytokines and immunotherapy. Treatment of a short-term explant culture of malignant epithelial cells from a KPC-Brca1 mouse pancreatic carcinoma, with 0.5 micromolar 5-aza-dC (decitabine; DAC) for 48 hours. The experiment includes 3 replicate plates untreated and 3 replicates treated.
Project description:Expression data from pancreatic cancer cell lines and non-neoplastic pancreatic cell line HPDE To identify genes epigenetically silenced and regulated in pancreatic cancer We compared the gene expression profiles of 6 pancreatic cancer cell lines (panc215, A32-1, A38-5, panc2.5, panc2.8, and panc3.014), to the non-neoplastic pancreas cell line, HPDE. We also compared the baseline gene expression of the pancreatic cancer cell lines to expression patterns after treatment with 5-aza-dC alone, TSA alone, and to a combination of 5-aza-dC/TSA.
Project description:Azacitidine (AZA) and decitabine (DAC) are cytidine azanucleoside analogs with clinical activity in myelodysplastic syndromes (MDS) and potential activity in solid tumors. To better understand the mechanism of action of these drugs, we examined the effects of AZA and DAC in a panel of non-small cell lung cancer (NSCLC) cell lines. Of 5 NSCLC lines tested in a cell viability assay, all were sensitive to AZA (EC50 of 1.8–10.5 µM), while only H1299 cells were equally sensitive to DAC (EC50 of 5.1 µM). In the relatively DAC-insensitive cell line A549, both AZA and DAC caused DNA methyltransferase I depletion and DNA hypomethylation; however, only AZA significantly induced markers of DNA damage and apoptosis, suggesting that mechanisms in addition to, or other than, DNA hypomethylation are important for AZA-induced cell death. Cell cycle analysis indicated that AZA induced an accumulation of cells in sub-G1 phase, whereas DAC mainly caused an increase of cells in G2/M. Gene expression analysis of AZA- and DAC-treated cells revealed strikingly different profiles, with many genes distinctly regulated by each drug. In summary, while both AZA and DAC caused DNA hypomethylation, distinct effects were demonstrated on regulation of gene expression, cell cycle, DNA damage, and apoptosis.
Project description:Azacitidine (AZA) and decitabine (DAC) are cytidine azanucleoside analogs with clinical activity in myelodysplastic syndromes (MDS) and potential activity in solid tumors. To better understand the mechanism of action of these drugs, we examined the effects of AZA and DAC in a panel of non-small cell lung cancer (NSCLC) cell lines. Of 5 NSCLC lines tested in a cell viability assay, all were sensitive to AZA (EC50 of 1.8M-bM-^@M-^S10.5 M-BM-5M), while only H1299 cells were equally sensitive to DAC (EC50 of 5.1 M-BM-5M). In the relatively DAC-insensitive cell line A549, both AZA and DAC caused DNA methyltransferase I depletion and DNA hypomethylation; however, only AZA significantly induced markers of DNA damage and apoptosis, suggesting that mechanisms in addition to, or other than, DNA hypomethylation are important for AZA-induced cell death. Cell cycle analysis indicated that AZA induced an accumulation of cells in sub-G1 phase, whereas DAC mainly caused an increase of cells in G2/M. Gene expression analysis of AZA- and DAC-treated cells revealed strikingly different profiles, with many genes distinctly regulated by each drug. In summary, while both AZA and DAC caused DNA hypomethylation, distinct effects were demonstrated on regulation of gene expression, cell cycle, DNA damage, and apoptosis. A549 and H1299 cells were treated with a dose range (0.3M-bM-^@M-^S3.0 M-NM-<M) of AZA or DAC for 48 hours, and effects on gene expression were assessed by microarray analysis.
Project description:The hypomethylating agent 5-azacytidine (AZA) is the first-line induction therapy for AML patients unsuitable for intensive chemotherapy. The anti-tumor effect of AZA results in part from T-cell cytotoxic responses against MHC-I-associated peptides (MAPs) deriving from hypermethylated genomic regions such as cancer-testis antigens (CTAs), or endogenous retroelements (EREs). However, clear evidence supporting higher ERE MAPs presentation after AZA treatment in AML is lacking. Interestingly, we find that AZA-mediated DNMT2 inhibition leads to autophagy induction, which is responsible for mitigating ERE MAPs generation. To validate our findings, we examined the immunopeptidome of THP-1 cells treated with AZA combined with autophagy inhibitor, Spautin-1 or decitabine (DAC, non-DNMT2 inhibiting HMA) through a proteogenomic approach.