WGBS-seq and oxWGBS-seq Atlas for Oral Squamous Cell Carcinoma
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE212634 | GEO | 2023/04/05
REPOSITORIES: GEO
Similar Datasets
Project description:Active DNA demethylation in mammals involves TET-mediated oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxycytosine (5caC). However, genome-wide detection of 5fC at single-base resolution remains challenging. Here we present a bisulfite-free method for the whole-genome analysis of 5fC, based on a selective chemical labeling of 5fC and subsequent C-to-T transition during PCR. Base-resolution 5fC maps reveal limited overlap with 5hmC, with 5fC-marked regions more active than 5hmC-marked ones.
2015-09-07 | GSE66144 | GEO
Project description:DNA methylation at the 5-postion of cytosine (5mC) is a well-established epigenetic modification which regulates gene expression and cellular plasticity in development and disease. The ten-eleven translocation (TET) gene family is able to oxidize 5mC to 5-hydroxmethylcytosine (5hmC), providing an active mechanism for DNA demethylation, and may also provide its own regulatory function. Here we applied oxidative bisulfite sequencing to generate whole-genome DNA methylation and hydroxymethylation maps at single-base resolution in paired human liver and lung normal and cancer. We found that 5hmC is significantly enriched in CpG island (CGI) shores while depleted in CGS themselves, in particular at active genes, resulting in a 5hmC but not 5mC bimodal distribution around CGI corresponding to H3K4me1 marks. Hydroxymethylation on promoters, gene bodies, and transcription termination regions showed strong positive correlation with gene expression within and across tissues, suggesting that 5hmC is a mark of active genes and could play a role gene expression mediated by DNA demethylation. Comparative analysis of methylomes and hydroxymethylomes at differentially methylated regions (DMRs) revealed that 5hmC is significantly enriched in both tissue specific DMRs (t-DMRs) and cancer specific DMRs (c-DMRs), and 5hmC is negatively correlated with methylation changes, particularly in non-CGI associated DMRs. Analysis of differentially methylated regions (DMRs) in normal and tumor tissues revealed that gain or loss of 5hmC negatively correlated with changes in 5mC, especially on non-CGI associated DMRs, suggesting a profound role for hydroxymethylation in regulation of dynamic DNA demethylation. Together these findings indicate that changes in 5mC as well as in 5hmC and coupled to H3K4me1 correspond to differential gene expression in tissues and matching tumors, revealing an intricate gene expression regulation through interplay of methylome, hydroxymethylome, and histone modifications.
2016-10-05 | GSE70090 | GEO
Project description:DNA methylation at the 5-postion of cytosine (5mC) is a well-established epigenetic modification which regulates gene expression and cellular plasticity in development and disease. The ten-eleven translocation (TET) gene family is able to oxidize 5mC to 5-hydroxmethylcytosine (5hmC), providing an active mechanism for DNA demethylation, and may also provide its own regulatory function. Here we applied oxidative bisulfite sequencing to generate whole-genome DNA methylation and hydroxymethylation maps at single-base resolution in paired human liver and lung normal and cancer. We found that 5hmC is significantly enriched in CpG island (CGI) shores while depleted in CGS themselves, in particular at active genes, resulting in a 5hmC but not 5mC bimodal distribution around CGI corresponding to H3K4me1 marks. Hydroxymethylation on promoters, gene bodies, and transcription termination regions showed strong positive correlation with gene expression within and across tissues, suggesting that 5hmC is a mark of active genes and could play a role gene expression mediated by DNA demethylation. Comparative analysis of methylomes and hydroxymethylomes at differentially methylated regions (DMRs) revealed that 5hmC is significantly enriched in both tissue specific DMRs (t-DMRs) and cancer specific DMRs (c-DMRs), and 5hmC is negatively correlated with methylation changes, particularly in non-CGI associated DMRs. Analysis of differentially methylated regions (DMRs) in normal and tumor tissues revealed that gain or loss of 5hmC negatively correlated with changes in 5mC, especially on non-CGI associated DMRs, suggesting a profound role for hydroxymethylation in regulation of dynamic DNA demethylation. Together these findings indicate that changes in 5mC as well as in 5hmC and coupled to H3K4me1 correspond to differential gene expression in tissues and matching tumors, revealing an intricate gene expression regulation through interplay of methylome, hydroxymethylome, and histone modifications.
2016-10-05 | GSE70089 | GEO
Project description:Active DNA demethylation in mammals involves TET-mediated oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxycytosine (5caC). However, genome-wide detection of 5fC at single-base resolution remains challenging. Here we present a bisulfite-free method for the whole-genome analysis of 5fC, based on a selective chemical labeling of 5fC and subsequent C-to-T transition during PCR. Base-resolution 5fC maps reveal limited overlap with 5hmC, with 5fC-marked regions more active than 5hmC-marked ones. Utilization of cyclization-enabled C-to-T transition of 5fC (hence “fC-CET”) to obtain genome-wide map of 5fC at single-base resolution WT and TdgKO mES cell lines. Two non-enriched input DNAs (Input: preAI), two AI labeled samples (Input: AI), two pull-down output samples.
2015-09-07 | E-GEOD-66144 | biostudies-arrayexpress
Project description:DNA methylation 5mC specific detection has been limited by the mixed signals from traditional bisulfite sequencing or by the severe degradation of input during oxBS-seq pretreatment. Here, we presented a 5mC specific whole genome amplification method (5mC-WGA), with which we achieved whole genome bisulfite sequencing with 5mC retention from limited input down to 10 pg scale without 5hmC signals, presenting DNA 5mC methylome with high producibility and great accuracy.
2020-04-14 | GSE112875 | GEO
Project description:Through parallel processing of genomic DNA with bisulfite and oxidative bisulfite treatments on Illumina 450K arrays we resolved both 5mC and 5hmC in glioblastoma tissues. We developed and applied a novel technique for estimating 5mC, 5hmC, and unmethylated proportions from array data to glioblastoma tissues and compare with normal brain tissue. Genomic distribution of 5hmC was associated with features of transcription despite the glioblastoma genome being relatively depleted of 5hmC. When integrating 5mC and 5hmC data using a Gaussian finite mixture model approach, we observed significant associations between 5hmC levels and gene-sets involved in immune and RNA regulatory processes. We also observed an enrichment of 5hmC in introns, enhancer regions, and genes that are actively transcribed in glioblastomas from TCGA. Significant differences in patient survival were observed among classes of 5hmC obtained from a recursively partitioned mixture model. Glioblastoma dervied (n=30) DNA was subjected to tandem bisulfite and oxidative bisulfite conversion with an input of 4ug per sample using the TrueMethyl® kit v.1.1 (Cambridge Epigenetix) protocol optimized for Illumina HumanMethylation450 arrays.
2016-08-22 | E-GEOD-73895 | biostudies-arrayexpress
Project description:5-methylcytosine (5mC), the predominant epigenetic modification on DNA, plays critical roles in mammalian development and is dysregulated in various human pathologies. In mammals, the TET family of dioxygenases can oxidize 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC) in a stepwise manner. 5fC and 5caC are selectively recognized and excised by mammalian thymine DNA glycosylase (TDG), and restored to normal cytosine through base excision repair (BER). Once 5mC/5hmC is converted to 5fC and/or 5caC, the modified cytosine is committed to demethylation through BER. Thus 5fC and 5caC most likely mark active demethylation in the mammalian genome. Here we introduce a genome-wide approach to obtain single-base resolution maps of 5fC and 5caC, respectively. We show that, in mouse embryonic stem cells (mESCs), 5fC and 5caC are preferentially generated at highly hypomethylated regions and more active enhancers. Moreover, 5caC-marked regions are characterized by the lowest methylation and highest enhancer activity among all modification sites associated with 5hmC, 5fC and 5caC, and are enriched adjacent to pluripotency transcription factor (TF)-binding motifs. These observations, together with the surprising lack of overlap between 5fC and 5caC sites, highlight a gradient of Tet-mediated 5mC oxidation activity at regulatory elements in tuning epigenetic dynamics11. DNA immunoprecipitation coupled chemical-modification assisted bisulfite sequencing (DIP-CAB-Seq) for Tdg fl/fl and Tdg-/- mESCs
2015-01-20 | E-GEOD-56429 | biostudies-arrayexpress
Project description:Through parallel processing of genomic DNA with bisulfite and oxidative bisulfite treatments on Illumina 450K arrays we resolved both 5mC and 5hmC in glioblastoma tissues. We developed and applied a novel technique for estimating 5mC, 5hmC, and unmethylated proportions from array data to glioblastoma tissues and compare with normal brain tissue. Genomic distribution of 5hmC was associated with features of transcription despite the glioblastoma genome being relatively depleted of 5hmC. When integrating 5mC and 5hmC data using a Gaussian finite mixture model approach, we observed significant associations between 5hmC levels and gene-sets involved in immune and RNA regulatory processes. We also observed an enrichment of 5hmC in introns, enhancer regions, and genes that are actively transcribed in glioblastomas from TCGA. Significant differences in patient survival were observed among classes of 5hmC obtained from a recursively partitioned mixture model.
2016-08-22 | GSE73895 | GEO
Project description:Here we present APOBEC-coupled epigenetic sequencing (ACE-seq), a bisulfite-free method for localizing 5-hydroxymethylcytosine (5hmC) at single-base resolution with low DNA input. The method builds on the observation that AID/APOBEC family DNA deaminase enzymes can potently discriminate between cytosine modification states and exploits the non-destructive nature of enzymatic, rather than chemical, deamination. ACE-seq yielded high-confidence 5hmC profiles with at least 1,000-fold less DNA input than conventional methods. Applying ACE-seq to generate a base-resolution map of 5hmC in tissue-derived cortical excitatory neurons, we found that 5hmC was almost entirely confined to CG dinucleotides. The whole-genome map permitted cytosine, 5-methylcytosine (5mC) and 5hmC to be parsed and revealed genomic features that diverged from global patterns, including enhancers and imprinting control regions with high and low 5hmC/5mC ratios, respectively. Enzymatic deamination overcomes many challenges posed by bisulfite-based methods, thus expanding the scope of epigenome profiling to include scarce samples and opening new lines of inquiry regarding the role of cytosine modifications in genome biology.
2018-10-08 | GSE116016 | GEO
Project description:Although various methods have been developed for sequencing cytosine epigenetic modifications, specific and quantitative sequencing of the two major epigenetic modifications of cytosines, 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) at base-resolution is still challenging. Most times it requires subtraction of two methods to obtain both the true 5mC and 5hmC information, which increases noise and requires high sequencing depth. Recently we developed TET assisted pyridine borane sequencing (TAPS) for bisulfite-free direct sequencing of DNA methylation, which provides the sum of 5mC and 5hmC. Here we extend it to two sister methods, TAPSβ and CAPS (Chemical-Assisted Pyridine borane Sequencing), for whole-genome subtraction-free and specific sequencing of 5mC and 5hmC, respectively. We also demonstrated Pyridine borane Sequencing (PS) of whole-genome 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC), the further oxidized derivatives of 5mC and 5hmC. This completes the versatile borane reduction chemistry-based methods as a comprehensive suite for direct and quantitative sequencing of all four individual cytosine epigenetic modifications.
2020-12-14 | GSE155613 | GEO