Epigenome Analysis of Post-Mortem Human Temporal Pole Brain Tissue
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: John Gilbert
PROVIDER: E-GEOD-67419 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Genome wide DNA methylation profiling of peripheral blood samples. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs. Samples included 63 of male samples,and 54 of female samples from peripheral leukocytes. All samples were healthy controls. Bisulphite converted DNA from the 117 samples were hybridised to the Illumina Infinium 450k Human Methylation Beadchip. Samples 1-93 were used in a pilot experiment and Samples 101-124 were used in a replicated experiment.
2016-03-01 | E-GEOD-67393 | biostudies-arrayexpress
Project description:Increasing evidence has demonstrated that epigenetic factors can profoundly influence gene expression and, in turn, influence resistance or susceptibility to disease. Epigenetic drugs, such as histone deacetylase (HDAC) inhibitors, are finding their way into clinical practice, although their exact mechanisms of action are unclear. To identify mechanisms associated with HDAC inhibition, we performed microarray analysis on brain and muscle samples treated with the HDAC1/3-targeting inhibitor, HDACi 4b. Pathways analyses of microarray datasets implicate DNA methylation as significantly associated with HDAC inhibition. Further assessment of DNA methylation changes elicited by HDACi 4b in human fibroblasts from normal controls and patients with Huntington's disease (HD) using the Infinium HumanMethylation450 BeadChip revealed a limited, but overlapping, subset of methylated CpG sites that were altered by HDAC inhibition in both normal and HD cells. Among the altered loci of Y chromosome-linked genes, KDM5D, which encodes Lys (K)-specific demethylase 5D, showed increased methylation at several CpG sites in both normal and HD cells, as well as in DNA isolated from sperm from drug-treated male mice. Further, we demonstrate that first filial generation (F1) offspring from drug-treated male HD transgenic mice show significantly improved HD disease phenotypes compared with F1 offspring from vehicle-treated male HD transgenic mice, in association with increased Kdm5d expression, and decreased histone H3 Lys4 (K4) (H3K4) methylation in the CNS of male offspring. Additionally, we show that overexpression of Kdm5d in mutant HD striatal cells significantly improves metabolic deficits. These findings indicate that HDAC inhibitors can elicit transgenerational effects, via cross-talk between different epigenetic mechanisms, to have an impact on disease phenotypes in a beneficial manner. Bisulphite converted DNA from the 12 samples were hybridised to the Illumina Infinium 27k Human Methylation Beadchip v1.2. We demonstrate that histone deacetylase (HDAC) inhibition can elicit changes in DNA methylation in Huntington’s disease (HD) human fibroblasts, as well as in sperm from HD transgenic mice, in association with DNA methylation-related gene expression changes. We suggest that alterations in sperm DNA methylation lead to transgenerational effects, and, accordingly, we show that first filial generation (F1) offspring of HDAC inhibitor-treated male HD transgenic mice show improved HD disease phenotypes compared with F1 offspring from vehicle-treated male HD transgenic mice. These findings have significant implications for human health because they enforce the concept that ancestral drug exposure may be a major molecular factor that can affect disease phenotypes, yet in a positive manner. Further, we implicate Lys (K)-specific demethylase 5d expression in this phenomenon.
2015-04-10 | E-GEOD-67733 | biostudies-arrayexpress
Project description:Background: In vitro models are an essential tool towards understanding the molecular characteristics of colorectal cancer (CRC) and the testing of therapies for CRC. To this end we established 21 novel CRC cell lines of which six were derived from liver metastases. Extensive genetic, genomic, transcriptomic and methylomic profiling was performed in order to characterize these new cell lines and all data is made publically available. Additionally, sensitivity of oxaliplatin was tested as a measure for chemotherapy resistance. Results: DNA copy-number alterations (CNA) were compared between primary and metastasis derived cell lines. In concordance with previous studies copy-number gain of chr20, and loss of chr8p were found highly specific for liver metastases. Previously reported BRAF-mutation associated DNA methylation profiles could be validated on the genome-wide DNA methylation profiles of these cell lines. 47.6% of the loci previously reported to associate with BRAF mutation status were reproduced in this dataset. When examining the gene expression profiles in conjunction with these DNA methylation results, we identified 20 genes of which the gene expression correlated with the DNA methylation status, including MEIS1, LRAT and STC2. These genes have previously been reported to be subject to transcriptional regulation through DNA hypermethylation, validating our approach. Conclusions: By combining mutation profiles with CNA and gene expression profiles we constructed an overview of the alterations in the major CRC-related signalling pathways. The mutation profiles, along with the genome, transcriptome and methylome data of these cell lines will be made publically available . This combined dataset puts these cell lines among the best characterized CRC cell lines, allowing researchers to select appropriate cell line models for their particular experiment, making optimal use of these novel cell lines as in vitro model for CRC. 21 CRC cell lines were analyzed
2016-02-29 | E-GEOD-67772 | biostudies-arrayexpress
Project description:Gene expression is regulated by genetic variants and DNA methylation with evidence from molecular biology studies, as well as expression QTL (eQTL) mapping and methylation QTL (mQTL) mapping. In this study, we explored the interaction between genetic variants and DNA methylation for its influence on gene expression. We analyzed a postmortem brain data and identified 2,768 SNP-methylation interaction (SMI) that can survive Bonferroni correction for the number of tests in cis- region of each gene. Seven SNP-methylation pairs were significant after Bonferroni correction for all the tests, including number of gene expression traits, we performed in this study. Only a small proportion of the SMI had evidence from the exact same SNP-transcript pair in eQTL mapping or SNP-methylation pair in mQTL mapping. This suggested that the interaction analysis could uncover novel regulatory relationships, which would be missed by eQTL or mQTL analyses. Since methylation per se is regulated by both genetic and environmental factors, analysis indicates that the SMI detected in this study may involve both genetic and environmental regulation. A total of 155 postmortem cerebellum brains were used in this study, including 47 bipolar disorder, 46 schizophrenia, 15 depression patients and 47 normal controls. All were of European Ancestry. We also designed 13 random replicates in our experiment. Illumina Infinium HumanMethylation27 BeadChip was used for DNA methylation profiling. The assay was performed at the Genomics Core Facility at Northwestern University.
2013-06-30 | E-GEOD-38873 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2016-02-29 | E-GEOD-67775 | biostudies-arrayexpress
Project description:In short: Genome wide promoter DNA methylation profiling of 43 T-ALL samples and 5 T-cell controls (normal bone marrow and stimulated T-cells) . The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs. Manuscript abstract: Background: Treatment of pediatric T-cell acute lymphoblastic leukemia (T-ALL) has improved, but there is a considerable fraction of patients experiencing a poor outcome. There is a need for better prognostic markers and aberrant DNA methylation is a candidate in other malignancies, but its potential prognostic significance in T-ALL is hitherto undecided. Design and Methods: Genome wide promoter DNA methylation analysis was performed in pediatric T-ALL samples (n=43) using arrays covering >27000 CpG sites. Clinical outcome was evaluated in relation to methylation status and compared with a contemporary T-ALL group not tested for methylation (n= 32). Results: Based on CpG island methylator phenotype (CIMP), T-ALL samples were subgrouped as CIMP+ (high methylation) and CIMP- (low methylation). CIMP- T-ALL patients had significantly worse overall and event free survival (p=0.02 and p=0.001, respectively) compared to CIMP+ cases. CIMP status was an independent factor for survival in multivariate analysis including age, gender and white blood cell count. Analysis of differently methylated genes in the CIMP subgroups showed an overrepresentation of transcription factors, ligands and polycomb target genes. Conclusions: We identified global promoter methylation profiling as being of relevance for subgrouping and prognostication of pediatric T-ALL. Bisulphite converted DNA from the 48 samples were hybridised to the Illumina Infinium 27k Human Methylation Beadchip v1.2
2013-07-01 | E-GEOD-42079 | biostudies-arrayexpress
Project description:One pending issue in cardiovascular epigenetics is whether cerebrovascular events, a major complication of atherosclerosis, are associated with any specific DNA methylation changes in the carotid plaque. To clarify that topic, we profiled the DNA methylomes of human symptomatic carotid plaques (SCPs) obtained from patients who suffered cerebrovascular events (n=19) and asymptomatic counterparts (ACP; n=19) with a high-density microarray (~485,000 CpG sites, Illumina), and crossed DNA methylation data with RNAseq-based expression data from an independent SCP set (n=8). Few (30) CpGs showed a significant (p<0.05; absolute Delta-Beta>0.20) differential methylation between the two groups. Within SCPs, methylation correlated significantly with post-cerebrovascular event time (PCET; range: 3-45 days; r-value range -0.926 to 0.857; p<0.05) for ~45,000 CpGs, the vast majority of which became hypomethylated with increasing PCET. Hypomethylation was not due to erasure of the gene-body and CG-poor region hypermethylation that accompany the progression of stable lesions, but rather targeted promoters and CpG islands. Noticeably, promoter hypomethylation and increased expression were observed for genes involved in the inhibition of the inflammatory response, defence against oxidative stress and active DNA demethylation. Our data show that only weak changes in the DNA methylome distinguish symptomatic from asymptomatic carotid plaques, but a widespread demethylation resulting in permissive transcriptional marks at atheroprotective gene promoters is established in plaques after a cerebrovascular event, thus mirroring previous observations that ruptured plaques tend to revert to a more stable structure. The identified loci are candidate targets to accelerate the pace of carotid plaque stabilization. DNA was quantified by Quant-iT PicoGreen dsDNA Reagent (Invitrogen) and the integrity was analyzed in a 1.3% agarose gel. Bisulfite conversion of 600 ng of each sample was perform according to the manufacturer's recommendation for Illumina Infinium Assay. Effective bisulphite conversion was checked for three controls that were converted simultaneously with the samples. 4 ul of bisulfite converted DNA were used to hybridize on Infinium HumanMethylation 450 BeadChip, following Illumina Infinium HD Methylation protocol. Chip analysis was performed using Illumina HiScan SQ fluorescent scanner. The intensities of the images are extracted using GenomeStudio (2011.2) Methylation module (1.8.5) software. Methylation score of each CpG is represented as beta value.
2015-05-14 | E-GEOD-66500 | biostudies-arrayexpress
Project description:To broaden our understanding of the gene expression common to volar skin, we biopsied the dorsum of the hand, palm, dorsum of the foot and sole and collected DNA for methylation chip anlayses Total of 12 skin biopsy samples with 3 repeats from distinct individuals of each site: dorsum of hand, palm, dorstum of foot and sole. The samples below represent methylation data only.
2013-07-03 | E-GEOD-39131 | biostudies-arrayexpress
Project description:There is evidence indicating the involvement of DNA methylation memory in maintaining gene expression patterns associated with insulin resistance. Although the exact mechanism remains unknown, it has been proved that insulin resistance is correlated to low heat shock protein (HSP) expression. We reveal that intranuclear insulin can reduce HSP DNA methylation level to up-regulate HSP protein expression and result in long term cure of hyperglycemia. Insulin resistance HepG2 cell were selected in our experiments.Two conditions were compared with three replicates each. These are:(1) Insulin resistance HepG2(R-HepG2) and (2) Biomineralized insulin treated HepG2 (BI).
2014-05-23 | E-GEOD-57894 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2013-07-01 | E-GEOD-42080 | biostudies-arrayexpress