Project description:Affymetrix U95Av2 expression data from human intestinal cells (Caco-2) and tissues from all intestinal segments (duodenum, jejunum, ileum, colon). Entries contain the search terms glycosylase, phosphorylase, cytochrome or nucleoside, which were relevant to our search for enzymes capable of cleaving the N-glycosidic bond of nucleoside analog drugs.
Project description:Affymetrix U95Av2 expression data from human intestinal cells (Caco-2) and tissues from all intestinal segments (duodenum, jejunum, ileum, colon). Entries contain the search terms "glycosylase, phosphorylase, cytochrome or nucleoside," which were relevant to our search for enzymes capable of cleaving the N-glycosidic bond of nucleoside analog drugs. Keywords = glycosylase Keywords = phosphorylase Keywords = nucleoside Keywords: parallel sample
Project description:The FDA-approved DNA hypomethylating agents (DHAs) like 5-azacytidine (5AC) and decitabine (DAC) demonstrate efficacy in the treatment of hematologic malignancies. Despite previous reports that showed histone acetylation changes upon using these agents, the exact mechanism underpinning these changes is unknown. In this study, we investigated the relative potency of the nucleoside analogs and non-nucleoside analogs DHAs on DNA methylation reversal using DNA pyrosequencing. Additionally, we screened their effect on the enzymatic activity of the histone deacetylase sirtuin family (SIRT1, SIRT2, SIRT3, SIRT5 and SIRT6) using both recombinant enzymes and nuclear lysates from leukemia cells. The nucleoside analogs (DAC, 5AC and zebularine) were the most potent DHAs and increased the enzymatic activity of SIRT6 without showing any significant increase in other sirtuin isoforms. ChIP-Seq analysis of bone marrow cells derived from six acute myeloid leukemia (AML) patients and treated with the nucleoside analog DAC induced genome-wide acetylation changes in H3K9, the physiological substrate for SIRT6. Data pooling from the six patients showed significant acetylation changes in 187 gene loci at different chromosomal regions including promoters, coding exons, introns and distal intergenic regions. Signaling pathway analysis showed that H3K9 acetylation changes are linked to AML-relevant signaling pathways like EGF/EGFR and Wnt/Hedgehog/Notch. To our knowledge, this is the first report to identify the nucleoside analogs DHAs as activators of SIRT6. Our findings provide a rationale against the combination of the nucleoside analogs DHAs with SIRT6 inhibitors or chemotherapeutic agents in AML due to the role of SIRT6 in maintaining genome integrity and DNA repair.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
