Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA155697 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:This SuperSeries is composed of the following subset Series: GSE35911: Reversal of Aberrant Cancer Methylome and Transcriptome upon Direct Reprogramming of Lung Cancer Cells [Expression] GSE35912: Reversal of Aberrant Cancer Methylome and Transcriptome upon Direct Reprogramming of Lung Cancer Cells [Methylation] Refer to individual Series
2012-08-27 | E-GEOD-35913 | biostudies-arrayexpress
Project description:Reversal of Aberrant Cancer Methylome and Transcriptome upon Direct Reprogramming of Lung Cancer Cells [Expression]
| PRJNA155695 | ENA
Project description:DNA methylation reprogramming of primordial germ cells (PGCs) is an essential step that affects the activation and inactivation of certain genes, therefore having a direct impact on the transcriptome of an individual. In this study, we have described the methylome landscape of porcine PGCs, characterizing the genomic elements that resist methylation erasure.
2021-02-04 | E-MTAB-9326 | biostudies-arrayexpress
Project description:he ability to induce pluripotent stem cells from committed, somatic human cells provides tremendous potential for regenerative medicine. However, there is a defined neoplastic potential inherent to such reprogramming that must be understood and may provide a model for understanding key events in tumorigenesis. Using genome-wide assays, we identify cancer-related epigenetic abnormalities that arise early during reprogramming and persist in induced pluripotent stem cell (iPS) clones. These include hundreds of abnormal gene silencing events, patterns of aberrant responses to epigenetic-modifying drugs resembling those for cancer cells, and presence in iPS and partially reprogrammed cells of cancer-specific gene promoter DNA methylation alterations. Our findings suggest that by studying the process of induced reprogramming, we may gain significant insight into the origins of epigenetic gene silencing associated with human tumorigenesis, and add to means of assessing iPS for safety. Methylation was analyzed using Illumina's 27k Infinium platform for direct detection of methylation after bisulfite conversion. The overall methylation status was determined for several iPS lines and the pool cells from which they are derived. These methylation levels can be compared directly to those of cultured stem cells, differentiated cells and cancer cell lines.
2011-06-16 | E-GEOD-29872 | biostudies-arrayexpress
Project description:The ability to induce pluripotent stem cells from committed, somatic human cells provides tremendous potential for regenerative medicine. However, there is a defined neoplastic potential inherent to such reprogramming that must be understood and may provide a model for understanding key events in tumorigenesis. Using genome-wide assays, we identify cancer-related epigenetic abnormalities that arise early during reprogramming and persist in induced pluripotent stem cell (iPS) clones. These include hundreds of abnormal gene silencing events, patterns of aberrant responses to epigenetic-modifying drugs resembling those for cancer cells, and presence in iPS and partially reprogrammed cells of cancer-specific gene promoter DNA methylation alterations. Our findings suggest that by studying the process of induced reprogramming, we may gain significant insight into the origins of epigenetic gene silencing associated with human tumorigenesis, and add to means of assessing iPS for safety. Direct expression comparison of iPS lines, cultured stem cell lines and normal differentiated cells. Re-expression experiments with 5-aza-2′-deoxycytidine (AZA) and trichostatin A (TSA) to identify hypermethylated genes.
2011-06-16 | E-GEOD-29870 | biostudies-arrayexpress
Project description:Reprogramming to iPSCs resets the epigenome of somatic cells including the reversal of X chromosome-inactivation. We sought to gain insight into the steps underlying the reprogramming process by examining the means by which reprogramming leads to X chromosome-reactivation (XCR). Analyzing single cells in situ, we found that hallmarks of the inactive X (Xi) change sequentially, providing a direct readout of reprogramming progression. Several epigenetic changes on the Xi occur in the inverse order of developmental X-inactivation, while others are uncoupled from this sequence. Among the latter, DNA methylation has an extraordinary long persistence on the Xi during reprogramming, and, like Xist expression, is erased only after pluripotency genes are activated. Mechanistically, XCR requires both DNA demethylation and Xist silencing, ensuring that only cells undergoing faithful reprogramming initiate XCR. Our study defines the epigenetic state of multiple sequential reprogramming intermediates and establishes a paradigm for studying cell fate transitions during reprogramming. RRBS profiles were generated from female and male ES cells, female iPS cells, SSEA1+ and SSEA1- reprogramming intermediates, and male and female MEFs, for a total of 18 samples.
2014-12-18 | E-GEOD-58109 | biostudies-arrayexpress
Project description:Oncogenic imbalance of DNA methylation is well-recognized in cancer development. Ten-eleven translocation (TET) family of dioxygenases, which facilitate DNA demethylation, are frequently dysregulated in cancers. How such dysregulation contributes to tumorigenesis remains poorly understood, especially in solid tumors which present infrequent mutational incidence of TET genes. Here we identify TET mutations in 7.4% of human lung adenocarcinoma (LUAD), which frequently co-occur with oncogenic KRAS mutations, and this co-occurrence is predictive of poor survival in LUAD patients. Using autochthonous mouse model of KrasG12D-driven LUAD, we show that individual or combinational loss of Tet genes markedly promotes tumor development. In this Kras-mutant and Tet-deficient model, pre-malignant lung epithelium undergoes neoplastic reprogramming of DNA methylation and transcription, with a particular impact on Wnt signaling. Among the Wnt-associated components that undergo reprogramming, multiple canonical Wnt antagonizing genes present impaired expression arising from elevated DNA methylation, triggering aberrant activation of Wnt signaling. These impairments can be largely reversed upon the restoration of TET activity. Correspondingly, genetic depletion of β-catenin, the transcriptional effector of Wnt signaling, substantially reverts the malignant progression of Tet-deficient LUAD. These findings reveal TET enzymes as critical epigenetic barriers against lung tumorigenesis and highlight the therapeutic vulnerability of TET-mutant lung cancer through targeting Wnt signaling.
2022-02-23 | GSE185615 | GEO
Project description:Global loss of DNA methylation and locus/gene-specific gain of DNA methylation are two distinct hallmarks of carcinogenesis. Aberrant DNA methylation is implicated in smoking-related lung cancer. In this study, we have comprehensively investigated the modulation of DNA methylation consequent to chronic exposure to a prototype smoke-derived carcinogen, benzo[a]pyrene diol epoxide (B[a]PDE), in genomic regions of significance in lung cancer, in normal human cells. We have used a pulldown assay for enrichment of the CpG methylated fraction of cellular DNA combined with microarray platforms, followed by extensive validation through conventional bisulfite-based analysis. Here, we demonstrate strikingly similar patterns of DNA methylation in non-transformed B[a]PDE-treated cells vs control using high-throughput microarray-based DNA methylation profiling confirmed by conventional bisulfite-based DNA methylation analysis. The absence of aberrant DNA methylation in our model system within a timeframe that precedes cellular transformation suggests that following carcinogen exposure, other as yet unknown factors (secondary to carcinogen treatment) may help initiate global loss of DNA methylation and region-specific gain of DNA methylation, which can, in turn, contribute to lung cancer development. Unveiling the initiating events that cause aberrant DNA methylation in lung cancer has tremendous public health relevance, as it can help define future strategies for early detection and prevention of this highly lethal disease. Methylated fragments in genomic DNA extracted from benzo[a]pyrene diol epoxide (B[a]PDE)-treated normal human fibroblasts versus control (solvent [dimethylsulfoxide (DMSO)-treated counterpart cells] were enriched with the MIRA assay and hybridized together with input genomic DNA to NimbleGen's whole genome tiling array.
2010-04-29 | E-GEOD-21532 | biostudies-arrayexpress
Project description:Aberrant DNA hypermethylation of promoter CpG islands in the context of a hypomethylated genome is a hallmark of cancer. Thus far there is no human experimental model available to mechanistically investigate this phenomenon. Here we show that upon reprogramming of human embryonic stem cells to the naïve state, the acquisition of a globally hypomethylated genome is accompanied by hypermethylation of a subset of bivalent promoter CpG islands, resulting in a DNA methylome comparable to the human inner cell mass. We show that de novo methylation is carried out by DNMT3A and coordinated by the transcription factor network. We further show that the subset of bivalent sites that become hypermethyated are functionally distinct, with an enrichment in developmental genes, and demonstrate that this is mirrored in DNA hypermethylation patterns across cancer types, suggesting that common mechanisms may be responsible. We propose a wider utility of this experimental system to understand pre-malignant cancer-associated processes.
2020-06-12 | GSE128287 | GEO