Loss of 5-hydroxymethylcytosine is an epigenetic hallmark of melanoma
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE38231 | GEO | 2012/09/18
SECONDARY ACCESSION(S): PRJNA167460
REPOSITORIES: GEO
Similar Datasets
Project description:DNA methylation at the 5-position of cytosine (5-mC) is a key epigenetic mark critical for varius biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the Ten-Eleven Translocation (TET) family of DNA hydroxylases. Here we report that "loss of 5-hmC" is an epigenetic hallmark of melanoma with diagonostic and prognostic implications. Genome-wide mapping of 5-hmC in nevi and melanomas for the first time revealed loss of 5-hmC landscape in the melanoma epigenome. Downregulation of Isocitrate Dehydrogenase 2 (IDH2) and TET family enzymes proved to be one of the mechanisms underlying the loss of 5-hmC during melanoma development, and rebuilding the 5-hmC landscape in the melanoma epigenome by reintroducing active TET2 or IDH2 suppressed melanoma growth and increased tumor-free survival. Thus, our study establishes that "loss of 5-hmC" is a new epigenetic hallmark of melanoma and links IDH and TET family enzymes-mediated 5-hmC putative tumor suppressor pathway to the suppression of melanoma progression. Determine the genome-wide distribution of 5mC and 5hmC in benign nevus tissue, melanoma tissue, A2058 MOCK cells (overexpressing empty vector), A2058 TET2 cells (overexpressing wild type human TET), and A2058 TET2M cells (overexpressing mutant human TET).
2012-09-18 | E-GEOD-38231 | biostudies-arrayexpress
Project description:DNA methylation is a key regulatory event controlling a variety of physiological processes and can have dramatic effects on gene transcription. Methylated Cytosine (5mC) can be oxidized by the TET family of enzymes to 5-hydroxymethylcytosine (5-hmC), a key intermediate in the de-methylation cycle, and 5-hmC levels are reduced in malignancies such as AML and melanoma. We constructed a tissue microarray of human cutaneous Squamous Cell Carcinoma (SCC) tumors and found a global reduction in 5-hmC levels compared to adjacent skin. Using a murine K14-CreER system, we have found that loss of Tet2 promotes carcinogen-induced SCC, and cooperates with loss of Tp53 in to drive spontaneous SCC tumors in epithelial tissues. Loss of Tet2 in the normal epidermis leads to site-specific changes in 5-hmC levels, with many genes showing both increased and decreased levels of 5-hmC. Importantly, many of these changes were in genes regulating keratinocyte differentiation and self-renewal, consistent with reported roles for Tet enzymes in controlling lineage commitment in hematopoietic stem cells and ES cells. These results establish a functional role for Tet2 in the regulation of 5-hmC in the epidermis and demonstrate that Tet2 is a bone fide tumor suppressor in SCC.
2021-09-23 | GSE167949 | GEO
Project description:We studied global distribution of hydroxymethylation (5hmC) and DNA methylation (5mC) in during normal B-cell development and CLL maturation. To derive disease-specific epigenetic changes we have compared CLL subgroups to their corresponding cell of origin. Our data showed that naïve B-cells, compared to non-class switched and class switched memory B-cells, had higher levels of 5-hmC and 5-mC. By comparing with ChIP sequencing data of H3K27Ac and H3K4me1 modifications of CLL samples with 5hmC and 5mC levels, we observed an increase of 5-hmC at overall gene body regions, CpG island shores and regulatory elements. Comparing 5-hmC distribution with RNA sequencing we showed that genes with higher transcriptional activity had higher 5-hmC and vice versa. Thus, our study suggests that the global loss of 5-hmC levels, with significant increase at gene regulatory regions, constitute a novel hallmark of CLL pathogenesis.
2019-01-23 | GSE113386 | GEO
Project description:Ten-eleven translocation (Tet) family-mediated DNA oxidation represents a novel epigenetic modification capable of converting 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5-hmC) to regulate various biological processes. However, it is unknown whether the Tet family affects mesenchymal stem cells (MSCs) or the skeletal system. Here we show that depletion of Tet1 and Tet2 resulted in impaired self-renewal and differentiation of bone marrow MSCs (BMMSCs) and a significant osteopenia phenotype. Mechanistically, Tet1 and Tet2 deficiency reduced demethylation of the P2rX7 promoter and thus downregulated exosome release, leading to intracellular accumulation of miR-297a-5p, miR-297b-5p, and miR-297c-5p. These miRNAs inhibited Runx2 signaling to impair BMMSC function. We show that overexpression of P2rX7 consistently rescued the impaired BMMSCs and osteoporotic phenotype in Tet1 and Tet2 double knockout mice. These results indicate that Tet1 and Tet2 play a critical role in maintaining BMMSC and bone homeostasis through epigenetic regulation of P2rX7 to control exosome and miRNA release. This newly identified Tet/P2rX7/Runx2 cascade may serve as a target for the development of novel therapies for osteopenia disorders.
2018-04-11 | GSE108872 | GEO
Project description:DNA methylation is a heritable epigenetic modification involved in gene silencing, imprinting, and the suppression of retrotransposons. Global DNA demethylation occurs in the early embryo and the germline and may be mediated by Tet (ten-eleven-translocation) enzymes, which convert 5-methylcytosine (mC) to 5-hydroxymethylcytosine (hmC). Tet enzymes have been extensively studied in mouse embryonic stem (ES) cells, which are generally cultured in the absence of Vitamin C, a potential co-factor for Fe(II) 2-oxoglutarate dioxygenase enzymes like Tets. Here we report that addition of Vitamin C to ES cells promotes Tet activity leading to a rapid and global increase in hmC. This is followed by DNA demethylation of numerous gene promoters and up-regulation of demethylated germline genes. Tet1 binding is enriched near the transcription start site (TSS) of genes affected by Vitamin C treatment. Importantly, Vitamin C, but not other antioxidants, enhances the activity of recombinant human Tet1 in a biochemical assay and the Vitamin C-induced changes in hmC and mC are entirely suppressed in Tet1/2 double knockout (Tet DKO) ES cells. Vitamin C has the strongest effects on regions that gain methylation in cultured ES cells compared to blastocysts and in vivo are methylated only after implantation. In contrast, imprinted regions and intracisternal A-particle (IAP) elements, which are resistant to demethylation in the early embryo, are resistant to Vitamin C-induced DNA demethylation. Collectively, this study establishes that Vitamin C is a direct regulator of Tet activity and DNA methylation fidelity in ES cells. Oct4-GiP mouse embryonic stem (ES) cells were cultured in the presence or absence of Vitamin C (L-ascorbic acid 2-phosphate, 100 M-NM-<g/ml) for 12 or 72 hours. Cells were maintained in N2B27 medium supplemented with LIF (1000 U/ml), MEK inhibitor PD0325901 (1 M-NM-<M), and GSK3M-NM-2 inhibitor CHIR99021 (3 M-NM-<M). Genomic DNA was used for DNA immunoprecipitation with antibodies against 5-hydroxymethylcytosine (hmC) or 5-methylcytosine (mC). Immunoprecipitated DNA was adaptor-ligated for paired-end sequencing on an Illumina HiSeq and sequence reads were aligned to the mm9 mouse reference genome for analysis.
2013-06-30 | E-GEOD-46402 | biostudies-arrayexpress
Project description:Tet proteins oxidize 5-methylcytosine (mC) to generate 5-hydroxymethyl (hmC), 5-formyl (fC) and 5-carboxylcytosine (caC). The exact function of these oxidative cytosine bases remains elusive. We applied quantitative mass spectrometry-based proteomics to identify readers for mC and hmC in mouse embryonic stem cells (mESC), neuronal progenitor cells (NPC) and adult mouse brain tissue. Readers for these modifications are only partially overlapping and some readers, such as Rfx proteins, display strong specificity. Interactions are dynamic during differentiation, as for example evidenced by the mESC-specific binding of Klf4 to mC and the NPC-specific binding of Uhrf2 to hmC, suggesting specific biological roles for mC and hmC. Oxidized derivatives of mC recruit distinct transcription regulators as well as a large number of DNA repair proteins in mouse ES cells, implicating the DNA damage response as a major player in active DNA demethylation. Peptides were separated on an EASY-nLC (Proxeon) connected online to an LTQ-Orbitrap-Velos mass spectrometer. Spectra were recorded in CID mode. A gradient of organic solvent (5-30% acetonitrile) was applied (120 minutes) and the top 15 most abundant peptides were fragmented for MS/MS, using an exclusion list of 500 proteins for 45 seconds. Raw data were analyzed using Maxquant version 1.2.2.5 and the integrated Andromeda search engine against protein database ipi.MOUSE.v3.68. Using Perseus, data was filtered for contaminants, reverse hits, number of peptides (>1) and unique peptides (>0). Ratios were logarithmitized (log2) and groups (consisting of forward and reverse) were defined. Proteins were filtered to have at least 2 valid values in one of the groups and missing values were imputed based on a normal distribution (width=0.2 and shift=0), after which Significance B was calculated (Benj.Hoch.FDR=0.05). Scatterplots were made using R. Proteins were defined to be significant when both forward and reverse significance p<0.05 and minimal ratios were >2 in both experiments. The H/L ratios shown in Figure2A-C were calculated using the formula (log(forward ratio) - log(reverse ratio))/2.
2013-02-26 | PXD000143 | Pride
Project description:DNA methylation is a heritable epigenetic modification involved in gene silencing, imprinting, and the suppression of retrotransposons. Global DNA demethylation occurs in the early embryo and the germline and may be mediated by Tet (ten-eleven-translocation) enzymes, which convert 5-methylcytosine (mC) to 5-hydroxymethylcytosine (hmC). Tet enzymes have been extensively studied in mouse embryonic stem (ES) cells, which are generally cultured in the absence of Vitamin C, a potential co-factor for Fe(II) 2-oxoglutarate dioxygenase enzymes like Tets. Here we report that addition of Vitamin C to ES cells promotes Tet activity leading to a rapid and global increase in hmC. This is followed by DNA demethylation of numerous gene promoters and up-regulation of demethylated germline genes. Tet1 binding is enriched near the transcription start site (TSS) of genes affected by Vitamin C treatment. Importantly, Vitamin C, but not other antioxidants, enhances the activity of recombinant human Tet1 in a biochemical assay and the Vitamin C-induced changes in hmC and mC are entirely suppressed in Tet1/2 double knockout (Tet DKO) ES cells. Vitamin C has the strongest effects on regions that gain methylation in cultured ES cells compared to blastocysts and in vivo are methylated only after implantation. In contrast, imprinted regions and intracisternal A-particle (IAP) elements, which are resistant to demethylation in the early embryo, are resistant to Vitamin C-induced DNA demethylation. Collectively, this study establishes that Vitamin C is a direct regulator of Tet activity and DNA methylation fidelity in ES cells.
2013-06-30 | GSE46402 | GEO
Project description:DNA methylation is a heritable epigenetic modification involved in gene silencing, imprinting, and the suppression of retrotransposons. Global DNA demethylation occurs in the early embryo and the germline and may be mediated by Tet (ten-eleven-translocation) enzymes, which convert 5-methylcytosine (mC) to 5-hydroxymethylcytosine (hmC). Tet enzymes have been extensively studied in mouse embryonic stem (ES) cells, which are generally cultured in the absence of Vitamin C, a potential co-factor for Fe(II) 2-oxoglutarate dioxygenase enzymes like Tets. Here we report that addition of Vitamin C to ES cells promotes Tet activity leading to a rapid and global increase in hmC. This is followed by DNA demethylation of numerous gene promoters and up-regulation of demethylated germline genes. Tet1 binding is enriched near the transcription start site (TSS) of genes affected by Vitamin C treatment. Importantly, Vitamin C, but not other antioxidants, enhances the activity of recombinant human Tet1 in a biochemical assay and the Vitamin C-induced changes in hmC and mC are entirely suppressed in Tet1/2 double knockout (Tet DKO) ES cells. Vitamin C has the strongest effects on regions that gain methylation in cultured ES cells compared to blastocysts and in vivo are methylated only after implantation. In contrast, imprinted regions and intracisternal A-particle (IAP) elements, which are resistant to demethylation in the early embryo, are resistant to Vitamin C-induced DNA demethylation. Collectively, this study establishes that Vitamin C is a direct regulator of Tet activity and DNA methylation fidelity in ES cells.
2013-06-30 | GSE46319 | GEO
Project description:Background: 5-methylcytosine (5-mC) and its oxidized form, 5-hydroxymethylcytosine (5-hmC), are distinct epigenetic marks that help regulate gene expression in the mammalian brain. Existing studies have identified associations between 5-mC and neurodegenerative disease, but little work has examined the potential role of 5-hmC in Parkinson’s disease (PD) or Alzheimer’s disease (AD). Here, we utilized PD postmortem brain tissue and a public dataset from postmortem AD brains to analyze the effect of neurodegenerative disease on paired 5-mC and 5-hmC levels. Results: In PD samples, we measured genome-wide 5-mC and 5-hmC from control (n=3) and PD (n=6) brains using the Illumina EPIC array combined with bisulfite and oxidative bisulfite treatments (BS/oxBS-EPIC). In publicly sourced data, genome-wide 5-mC and 5-hmC were measured from control (n=25) and AD (n=62) human entorhinal cortex tissue using the Illumina 450K array combined with bisulfite and oxidative bisulfite treatment (BS/oxBS-450K). Paired 5-mC and 5-hmC beta values were generated using a custom pipeline of bioinformatics tools, and we modeled the effect of disease on paired 5-mC and 5-hmC data using a mixed effects beta regression model with a random effect for ID and an interaction term between disease category and DNA modification category (“5-mC” or “5-hmC”). We identified a number of CpG probes (AD: n=699, PD: total n = 80) that showed a significant interaction between disease status and DNA modification category (p-value < 2.4x10-7). Conclusions: While our PD data requires additional validation, our analyses suggest that there are widespread shifts in the balance between 5-mC and 5-hmC in Parkinson’s and Alzheimer’s disease.
2019-10-09 | GSE138597 | GEO
Project description:DNA methylation is a heritable epigenetic modification involved in gene silencing, imprinting, and the suppression of retrotransposons. Global DNA demethylation occurs in the early embryo and the germline and may be mediated by Tet (ten-eleven-translocation) enzymes, which convert 5-methylcytosine (mC) to 5-hydroxymethylcytosine (hmC). Tet enzymes have been extensively studied in mouse embryonic stem (ES) cells, which are generally cultured in the absence of Vitamin C, a potential co-factor for Fe(II) 2-oxoglutarate dioxygenase enzymes like Tets. Here we report that addition of Vitamin C to ES cells promotes Tet activity leading to a rapid and global increase in hmC. This is followed by DNA demethylation of numerous gene promoters and up-regulation of demethylated germline genes. Tet1 binding is enriched near the transcription start site (TSS) of genes affected by Vitamin C treatment. Importantly, Vitamin C, but not other antioxidants, enhances the activity of recombinant human Tet1 in a biochemical assay and the Vitamin C-induced changes in hmC and mC are entirely suppressed in Tet1/2 double knockout (Tet DKO) ES cells. Vitamin C has the strongest effects on regions that gain methylation in cultured ES cells compared to blastocysts and in vivo are methylated only after implantation. In contrast, imprinted regions and intracisternal A-particle (IAP) elements, which are resistant to demethylation in the early embryo, are resistant to Vitamin C-induced DNA demethylation. Collectively, this study establishes that Vitamin C is a direct regulator of Tet activity and DNA methylation fidelity in ES cells. Oct4-GiP mouse embryonic stem (ES) cells were cultured in the presence or absence of Vitamin C (L-ascorbic acid 2-phosphate, 200 M-NM-<g/ml) for 72 hours. RNA was harvested from biological triplicates for each condition and hybridized to Affymetrix microarrays. Cells were maintained in N2B27 medium supplemented with LIF (1000 U/ml), MEK inhibitor PD0325901 (1 M-NM-<M), and GSK3M-NM-2 inhibitor CHIR99021 (3 M-NM-<M).
2013-06-30 | E-GEOD-46319 | biostudies-arrayexpress