Project description:COHCAP (City of Hope CpG Island Analysis Pipeline) is an algorithm to analyze single-nucleotide resolution DNA methylation data. It provides QC metrics, differential methylation for CpG Sites, differential methylation for CpG Islands, integration with gene expression data, and visualization of methylation values. COHCAP is currently the only DNA methylation package that can handle integration with gene expression data, and the results of this study show that COHCAP can identify regions of differential methylation with ~50% concordance with gene expression. COHCAP is scalable for analysis of both cell line data and heterogeneous patient data, and it can identify known cancer biomarkers as well as intriguing new roles of epigenetic regulation in cancer (such as methylation of estrogen receptor in breast cancer patients). This study also uses cell line data to show that COHCAP is capable of analyzing Illumina methylation array and targeted bisulfite sequencing data, with either 1-group or 2-group study designs. The accuracy of COHCAP is accessed using qPCR, EpiTect, and comparison of COHCAP regions of differential methylation with MIRA peaks. This software is freely available at https://sourceforge.net/projects/cohcap/. The following third-party datasets were utilized in the paper: BS-Seq data: GSE26826 Additional Microarray Data: GSE29290 This SuperSeries is composed of the SubSeries listed below.
Project description:COHCAP (City of Hope CpG Island Analysis Pipeline) is an algorithm to analyze single-nucleotide resolution DNA methylation data. It provides QC metrics, differential methylation for CpG Sites, differential methylation for CpG Islands, integration with gene expression data, and visualization of methylation values. COHCAP is currently the only DNA methylation package that can handle integration with gene expression data, and the results of this study show that COHCAP can identify regions of differential methylation with ~50% concordance with gene expression. COHCAP is scalable for analysis of both cell line data and heterogeneous patient data, and it can identify known cancer biomarkers as well as intriguing new roles of epigenetic regulation in cancer (such as methylation of estrogen receptor in breast cancer patients). This study also uses cell line data to show that COHCAP is capable of analyzing Illumina methylation array and targeted bisulfite sequencing data, with either 1-group or 2-group study designs. The accuracy of COHCAP is accessed using qPCR, EpiTect, and comparison of COHCAP regions of differential methylation with MIRA peaks. This software is freely available at https://sourceforge.net/projects/cohcap/. The following third-party datasets were utilized in the paper: BS-Seq data: GSE26826 Additional Microarray Data: GSE29290 This SuperSeries is composed of the SubSeries listed below. Refer to individual Series.
Project description:We compare the methylation status of CpG island clones by MeDIP in SW48 colon cancer cells relative to normal colon mucosa and WI38 primary fibroblasts. Keywords: ordered
Project description:To globally define methylation-’prone’ and -’protected’ CpG islands in cancer, we analyzed the methylation status of 23,000 CpG islands of the human genome in 19 colorectal carcinoma samples as well as normal colon using our previously described methyl-CpG immunoprecipitation (MCIp) technique (Gebhard et al. 2006; Schilling and Rehli 2007). This method enriches for highly CpG methylated DNA that can be directly applied to fluorescent labeling and oligonucleotide microarray hybridization without an additional amplification step.
Project description:We compare the methylation status of CpG island clones by MeDIP in SW48 colon cancer cells relative to normal colon mucosa and WI38 primary fibroblasts.
Project description:Astrocytomas are common and lethal human brain tumors. Here, we have analyzed the methylation status of over 28,000 CpG islands and 18,000 promoters in normal human brain and in astrocytomas of various grades using the methylated-CpG island recovery assay (MIRA). We identified six to seven thousand methylated CpG islands in normal human brain. ~5% of the promoter-associated CpG islands in normal brain are methylated. Promoter CpG island methylation is inversely and intragenic methylation is directly correlated with gene expression levels in brain tissue. In astrocytomas, several hundred CpG islands undergo specific hypermethylation relative to normal brain with 428 methylation peaks common to more than 25% of the tumors. Genes involved in brain development and neuronal differentiation, such as POU4F3, GDNF, OTX2, NEFM, CNTN4, OTP, SIM1, FYN, EN1, CHAT, GSX2, NKX6-1, RAX, PAX6, DLX2, were strongly enriched among genes frequently methylated in tumors. There was an overrepresentation of homeobox genes and 31% of the most commonly methylated genes represent targets of the Polycomb complex. We identified several chromosomal loci in which many (sometimes more than 20) consecutive CpG islands were hypermethylated in tumors. Seven of such loci were near homeobox genes, including the HOXC and HOXD clusters, and the BARHL2, DLX1, and PITX2 genes. Two other clusters of hypermethylated islands were at sequences of recent gene duplication events. Our analysis offers mechanistic insights into brain neoplasia suggesting that methylation of genes involved in neuronal differentiation, perhaps in cooperation with other oncogenic events, may shift the balance from regulated differentiation towards gliomagenesis.
Project description:To globally define methylation-M-bM-^@M-^YproneM-bM-^@M-^Y and -M-bM-^@M-^YprotectedM-bM-^@M-^Y CpG islands in cancer, we analyzed the methylation status of 23,000 CpG islands of the human genome in 19 colorectal carcinoma samples as well as normal colon using our previously described methyl-CpG immunoprecipitation (MCIp) technique (Gebhard et al. 2006; Schilling and Rehli 2007). This method enriches for highly CpG methylated DNA that can be directly applied to fluorescent labeling and oligonucleotide microarray hybridization without an additional amplification step. CpG-methylated genomic DNA was enriched using methyl-CpG immunoprecipitation (MCIp). On each microarray, the enriched material from colorectal carcinoma samples was compared to the enriched material from normal colon to identify aberrantly methylated regions.
Project description:Astrocytomas are common and lethal human brain tumors. Here, we have analyzed the methylation status of over 28,000 CpG islands and 18,000 promoters in normal human brain and in astrocytomas of various grades using the methylated-CpG island recovery assay (MIRA). We identified six to seven thousand methylated CpG islands in normal human brain. ~5% of the promoter-associated CpG islands in normal brain are methylated. Promoter CpG island methylation is inversely and intragenic methylation is directly correlated with gene expression levels in brain tissue. In astrocytomas, several hundred CpG islands undergo specific hypermethylation relative to normal brain with 428 methylation peaks common to more than 25% of the tumors. Genes involved in brain development and neuronal differentiation, such as POU4F3, GDNF, OTX2, NEFM, CNTN4, OTP, SIM1, FYN, EN1, CHAT, GSX2, NKX6-1, RAX, PAX6, DLX2, were strongly enriched among genes frequently methylated in tumors. There was an overrepresentation of homeobox genes and 31% of the most commonly methylated genes represent targets of the Polycomb complex. We identified several chromosomal loci in which many (sometimes more than 20) consecutive CpG islands were hypermethylated in tumors. Seven of such loci were near homeobox genes, including the HOXC and HOXD clusters, and the BARHL2, DLX1, and PITX2 genes. Two other clusters of hypermethylated islands were at sequences of recent gene duplication events. Our analysis offers mechanistic insights into brain neoplasia suggesting that methylation of genes involved in neuronal differentiation, perhaps in cooperation with other oncogenic events, may shift the balance from regulated differentiation towards gliomagenesis. Comparison of methylation patterns of 30 astrocytomas and 6 controls
Project description:The CpG island methylator phenotype (CIMP) can be regarded as the most notable emanation of epigenetic instability in cancer. Since its discovery in the late 1990s, CIMP has been extensively studied, mainly in colorectal cancers (CRC) and gliomas. Consequently, knowledge on molecular and pathological characteristics of CIMP in CRC and other tumour types has rapidly expanded. Concordant and widespread hypermethylation of multiple CpG islands observed in CIMP in multiple cancers raised hopes for future epigenetically based diagnostics and treatments of solid tumours. However, studies on CIMP in solid tumours were hampered by a lack of generalisability and reproducibility of epigenetic markers. Moreover, CIMP was not a satisfactory marker in predicting clinical outcomes. The idea of targeting epigenetic abnormalities such as CIMP for cancer therapy has not been implemented for solid tumours, either. Twenty-one years after its discovery, we aim to cover both the fundamental and new aspects of CIMP and its future application as a diagnostic marker and target in anticancer therapies.