BS-seq in plasma of CRC patients
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ABSTRACT:
PROVIDER: EGAS00001003117 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:We performed whole genome bisulfite sequencing of plasma DNA in 11 colorectal cancer patients to study the colonic DNA in plasma.
| EGAD00001004568 | EGA
Project description:We intend to establish an efficient method for plasma cfDNA extraction and Bisulfite transformation to facilitate the detection of DNA methylation status using multiplex fluorescence PCR. Meanwhile, we expect to identify several plasma methylation markers that can be highly sensitive for multi-cancer detection. Finally, we will provide a pan-cancer blood test that is easy to operate, low cost, accurate and easy to promote.
| 5068 | ecrin-mdr-crc
Project description:To characterize DNA methylation-based subgroups in colorectal cancer, we performed genome-scale DNA methylation profiling of 125 colorectal tumor samples and 29 histologically normal-adjacent colonic tissue samples using the Illumina Infinium DNA methylation assay, which assesses the DNA methylation status of 27,578 CpG sites located at the promoter regions of 14,495 protein-coding genes. We identified four DNA methylation-based subgroups of CRC using model-based cluster analyses. Each subtype shows characteristic genetic and clinical features, indicating that they represent biologically distinct subgroups. Bisulfite converted DNA from fresh frozen 125 colorectal tumors and 29 adjacent normal tissues were hybridized to the Illumina Infinium 27k Human Methylation Beadchip v1.2
2011-06-03 | E-GEOD-25062 | biostudies-arrayexpress
Project description:Colorectal cancer is the third most common cancer. Obesity is a major risk factor with long-lasting effects on the predisposition to colorectal cancer; however, the mechanistic underpinnings remain poorly understood. To explore epigenetic mechanisms involved, we performed whole-genome bisulfite sequencing and RNA-Seq in colonic epithelium from control mice, obese mice, and formerly obese mice. We found that obesity-induced DNA methylation changes reprogrammed the transcriptome leading to a metabolic switch favoring long chain fatty acid oxidation, which is essential to colonic stem cell functions and colon tumorigenesis. Remarkably, persistent changes were observed after weight loss mainly at metabolic and cancer-related genes, underlying the long-term predisposition to colorectal cancer. In summary, we provide the epigenetic and metabolic basis of the link between obesity and colorectal cancer.
2017-12-19 | GSE85731 | GEO
Project description:large-scale polar metabolomics analysis for plasma sample from colorectal cancer patients
| MSV000092836 | GNPS
Project description:This study aimed to evaluate the cost-effective and genome-wide cell-free reduced representation bisulfite sequencing (cfRRBS) method combined with computational deconvolution for effective disease monitoring in patients with esophageal adenocarcinoma (EAC). cfDNA methylation profiling with cfRRBS was performed on 162 blood plasma samples from 33 EAC cancer patients and 28 blood plasma samples from 20 healthy donors. In addition, for reproducibility testing purposes of the method, 9 plasma samples were re-prepped (library was re-made) and re-sequenced once (n=9) or twice (n=1). As a reference for the data deconvolution cfRRBS was performed on 7 EAC tumor tissue (FFPE) samples.
2024-12-04 | E-MTAB-14370 | biostudies-arrayexpress
Project description:large-scale polar metabolomics analysis for plasma sample from colorectal cancer patients
| MSV000092836 | MassIVE
Project description:Genome-wide analysis of cell-free DNA (cfDNA) methylation profile has been recognized as a promising approach for sensitive and specific detection of many cancers. However, scaling such genome-wide assays for clinical translation is impractical due to the high cost of whole genome bisulfite sequencing. We have shown that the small fraction of GC-rich genome is highly enriched in CpG sites and disproportionately harbors the majority of cancer-specific methylation signature. Here, we report on the simple but effective Heat enrichment of CpG-rich regions for Bisulfite Sequencing (Heatrich-BS) platform that allows for focused methylation profiling in these highly informative regions. Our novel method and bioinformatics algorithm enable accurate tumor burden estimation with high sensitivity and quantitative tracking of colorectal cancer patient’s response to treatment, at much reduced sequencing cost suitable for frequent monitoring. We also show, for the first time, tumor epigenetic subtyping from cfDNA using Heatrich-BS, which could enable patient stratification from non-invasive liquid biopsy. As such, Heatrich-BS holds great potential for highly scalable screening and regular monitoring of cancer using liquid biopsy.
2022-07-21 | GSE208596 | GEO
Project description:As a non-invasive blood testing, the detection of cell-free DNA (cfDNA) methylation in plasma is raising increasing interest due to its diagnostic and biology applications. Although extensively used in cfDNA methylation analysis, bisulfite sequencing is less cost-effective. Through enriching methylated cfDNA fragments with MeDIP followed by deep sequencing, we aimed to characterize cfDNA methylome in cancer patients. In this study, we investigated the cfDNA methylation patterns in lung cancer patients by MeDIP-seq. MEDIPS package was used for the identification of differentially methylated regions (DMRs) between patients and normal ones. Overall, we identified 330 differentially methylated regions (DMRs) in gene promoter regions, 33 hypermethylation and 297 hypomethylation respectively, by comparing lung cancer patients and healthy individuals as controls. The 33 hypermethylation regions represent 32 genes. Some of the genes had been previously reported to be associated with lung cancers, such as GAS7, AQP10, HLF, CHRNA9 and HOPX. Taken together, our study provided an alternative method of cfDNA methylation analysis in lung cancer patients with potential clinical applications.
2019-03-31 | E-MTAB-7163 | biostudies-arrayexpress
Project description:DNA methylation (5-mC) and hydroxymethylation (5-hmC) are regarded as important epigenetic hallmarks in the carcinogenesis of colorectal cancer by transcriptional regulation. 5hmC is an intermediate during active demethylation and maintains the equilibrium of DNA methylation. Previous studies on DNA methylation don’t differentiate 5-hmC from 5-mC. Here, in order to elucidate the epigenetic mechanisms of carcinogenesis of colorectal cancer, we integrate genome wide levels of 5-mC, 5-hmC and Transcriptional expression. 12 samples, including six colorectal tumor tissues and corresponding normal colonic tissues were recruited after surgery. Genome-wide DNA methylation was determined by methylated DNA immune- precipitation sequencing (MeDIP-seq), and hydroxymethylation by hydroxyl- methylated DNA immune-precipitation sequencing (hMedip-seq). Transcriptional expression was determined by RNA-seq. Group-wise different methylation region (DMR), different hydroxyl methylation region (DhMR) and different expressed gene (DEG) were identified. Epigenetic biomarkers were screened by integrating DMR, DhMR and DEG. We found that a genome-scale distinct hydroxymethylation pattern could be used as epigenetic biomarker for clearly differentiating colorectal cancer from normal tissues. 59249 differentially methylated regions (DMR), 187172 differentially hydroxymethylated region (DhMR) and 948 differentially expressed genes (DEGs) were identified. After cross-matched genes containing DMRs or DhMRs with DEGs, seven genes were screened. Furthermore, hypermethylation of HADHB was persistently found to be correlated with its down-regulation of transcription in CRC, potentially suggesting its role as TSG. The differences of methylation, hydroxymethylation and transcriptional expression in HADHB between cancerous and normal tissues were validated among additional colorectal cancer patients. To further validate this assumption, we also performed functional analysis and found that the expression of HADHB obviously reduced cancer cells migration and invasiveness. This study provided valuable basic data for screening epigenetic biomarkers and elucidated the epigenetic mechanisms of carcinogenesis of colorectal cancer.
2018-12-31 | GSE87096 | GEO