Similar Datasets
Project description:DNA methylation gradiently changes with age and is likely to be involved in aging-related processes resulting in phenotype changes and increased susceptibility to certain diseases. The Hutchinson-Gilford Progeria Syndrome (HGP) and Werner Syndrome are two premature aging diseases showing features of common aging. Mutations in LMNA and WRN genes were associated to disease onset; however for a subset of patients the underlying causative mechanisms remain elusive. We aimed to evaluate the role of epigenetic alteration on premature aging diseases by performing genome-wide DNA methylation profiling of HGP and WS patients.
2013-01-14 | GSE42865 | GEO
Project description:DNA methylation in progeroid syndromes
| PRJNA544684 | ENA
Project description:Mutations in LMNA, encoding Lamin A/C, lead to a variety of diseases known as laminopathies that include dilated cardiomyopathy (DCM). The role of epigenetic mechanisms. such as DNA methylation, has not been thoroughly investigated. Furthermore, the impact of patient-specific LMNA mutations on DNA methylation is unknown. To explore the role of DNA methylation in the context of unique LMNA mutations, we performed reduced representation bisulfite sequencing (RRBS) on ten pairs of fibroblasts and their induced pluripotent stem cell (iPSC) derivatives from two families with DCM due to distinct LMNA mutations. Family-specific differentially methylated regions (DMRs) were identified by comparing the DNA methylation landscape of patient and control samples. Fibroblast DMRs were found to enrich for distal regulatory features and transcriptionally repressed chromatin and to associate with genes related to phenotypes found in laminopathies. These DMRs, in combination with transcriptome-wide expression data and Lamina-associated domain (LAD) organization, revealed the presence of inter-family epimutation hotspots near differentially expressed genes, most of which were located near redistributed LADs. Comparison of DMRs found in fibroblasts and iPSCs identified regions where epimutations were persistent across both cell types. Finally, a network of disease-associated genes dysregulated in LMNA mutated cells was uncovered, potentially due to aberrant methylation changes. In conclusion, the use of in vitro culture models of patient-derived cells and differential methylation analysis enabled the identification of epimutation hotspots and dysregulated genes, consistent with a Lamin A/C mutation-specific epigenetic disease mechanism that arose in somatic and early-developmental cell stages.
2021-07-20 | GSE164365 | GEO
Project description:Epigenetic dysregulation has emerged as mechanism in the etiology of neurodevelopmental disorders. Two such disorders, CHARGE and Kabuki syndromes, result from loss of function mutations in chromodomain helicase DNA-binding protein 7 (CHD7LOF) and lysine (K) methyltransferase 2D (KMT2DLOF), respectively. We expected that epigenetically driven developmental pathways regulated by CHD7 and KMT2D would overlap and that DNA methylation (DNAm) alterations downstream of the mutations in these genes would identify common target genes, elucidating a mechanistic link between these conditions, as well as specific target genes for each. Genome-wide DNAm profiles in individuals with CHARGE and Kabuki syndromes with CHD7LOF or KMT2DLOF identified distinct sets of DNAm differences in each of the disorders, which were used to generate two unique, highly specific and sensitive DNAm signatures. These DNAm signatures were able to differentiate pathogenic mutations in these two genes from controls and from each other. Analysis of each gene-specific DNAm signature identified common gene targets which could account for some of the clinical overlap in these syndromes, as well as distinct gene targets. Our findings demonstrate how characterization of the epigenome can contribute to our understanding of disease pathophysiology for epigenetic disorders, paving the way for explorations of novel therapeutics.
2017-05-03 | GSE97362 | GEO
Project description:Hitherto, most studies on POLD1 have mainly focused on the effect of POLD1 inactivation mutation in tumors. Nonetheless, the mechanism underlying high POLD1 expression in tumorigenesis remains elusive. Herein, we substantiated the pro-carcinogenic role of POLD1 in bladder cancer (BLCA) and found that POLD1 expression is related to malignancy and prognosis of BLCA. Next, we demonstrated that POLD1 could promote proliferation and metastasis of BLCA via MYC. Mechanistically, we demonstrated that POLD1 was able to stabilize MYC in a manner independent of DNA polymerase activity. POLD1 attenuated the FBXW7-mediated ubiquitination degradation of MYC by directly binding to the MYC homology box 1 domain competitively with FBXW7. Moreover, we found that POLD1 can form a complex with MYC to promote the transcriptional activity of MYC. MYC could also transcriptionally activate POLD1, forming a POLD1-MYC positive feedback loop to enhance the pro-carcinogenic effect of POLD1-MYC on BLCA. Overall, our study suggests a novel MYC-driven mechanism for BLCA, and POLD1 has the potential as a biomarker for BLCA.
2023-03-29 | PXD040806 | Pride
Project description:DNA methylation gradiently changes with age and is likely to be involved in aging-related processes resulting in phenotype changes and increased susceptibility to certain diseases. The Hutchinson-Gilford Progeria Syndrome (HGP) and Werner Syndrome are two premature aging diseases showing features of common aging. Mutations in LMNA and WRN genes were associated to disease onset; however for a subset of patients the underlying causative mechanisms remain elusive. We aimed to evaluate the role of epigenetic alteration on premature aging diseases by performing genome-wide DNA methylation profiling of HGP and WS patients. 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 (2010.3) Methylation module (1.8.5) software. Methylation score of each CpG is represented as beta value. Naive B-cells and peripheral blood mononuclear cells were analyzed to correct for the epigenetic effects of the Epstein-Barr virus immortalization (lymphoblastoid cell lines) and cell composition of the samples, respectively.
2013-01-14 | E-GEOD-42865 | biostudies-arrayexpress
Project description:Hitherto, most studies on DNA polymerase δ (POLD1) have mainly focused on the effect of POLD1 inactivation mutation in tumors. Nonetheless, the mechanism underlying high POLD1 expression in tumorigenesis remains elusive. Herein, we substantiated the pro-carcinogenic role of POLD1 in bladder cancer (BLCA) and found that POLD1 expression is related to malignancy and prognosis of BLCA. Next, we demonstrated that POLD1 could promote proliferation and metastasis of BLCA via MYC in vivo and in vitro. Furthermore, POLD1 and MYC were colocalized in the nucleus and co-expressed during the cell cycle. Mechanistically, we validated that POLD1 could interact directly with MYC, and POLD1 could stabilize MYC by counteracting GSK3β-mediated phosphorylation of threonine 58 and blocking the interaction between E3 ubiquitin ligase FBXW7 and MYC. Moreover, MYC could transcriptionally activate POLD1, forming a POLD1-MYC positive feedback loop to enhance the pro-carcinogenic effect of POLD1-MYC on BLCA. Overall, our study identified a novel MYC-driven oncogene POLD1, providing a potential diagnostic and therapeutic target for BLCA.
2022-04-22 | GSE200897 | GEO
Project description:Constitutive heterochromatin is responsible for genome repression of DNA enriched in repetitive sequences, telomeres, and centromeres. In higher eukaryotes, constitutive heterochromatin is mostly segregated at the nuclear periphery, where the interaction with the nuclear lamina makes the genome more resistant to transcription. During physiological and pathological premature aging, heterochromatin homeostasis is profoundly compromised. Here we show that LINE-1 (L1) RNA accumulation is an early event in both typical and atypical progeroid syndromes. Depletion of L1 RNA in cells from different progeroid syndrome patients using specific antisense oligonucleotides (ASO) restores the levels of heterochromatin epigenetic marks, reverses DNA methylation age and counteracts the expression of senescence-associated genes. Moreover, proteome profiling involved in senescence phenotype was partially restored upon depletion of LINE-1 RNA in both Hutchinson-Gilford Progeria Syndrome (HGPS) and Werner syndrome (WRN-/-).
2022-11-02 | PXD032944 | Pride
Project description:<p>Werner syndrome (WS) is an adult-onset progeroid syndrome characterized by accelerated aging. The International Registry of Werner Syndrome in the Department of Pathology, University of Washington, collects WS cases from all over the world. Classical WS is caused by WRN mutations. Those who do not carry <i>WRN</i> are categorized as "atypical Werner syndrome." A small subset of atypical WS is caused by <i>LMNA</i> mutations. There also are many cases whose causes are still unknown. The purpose of this study is to identify other causative gene(s) of atypical WS.</p>
| phs000434 | dbGaP
Project description:Progeroid syndromes are rare genetic diseases with a majority of autosomal dominant transmission, the prevalence of which is less than 1 / 10,000,000. These syndromes caused by mutations in the LMNA gene encoding A-type Lamins belong to the group of disorders called laminopathies. Lamins are implicated in the architecture and function of the nucleus and chromatin. Patients affected with progeroid laminopathies display accelerated ageing of mesenchymal stem cells (MSCs)-derived tissues associated with nuclear morphological abnormalities. In order to identify pathways altered in progeroid patients’ MSCs, we used induced pluripotent stem cells (hiPSCs) from patients affected with classical Hutchinson-Gilford Progeria Syndrome (HGPS, c.1824C>T - p.G608G), HGPS-Like Syndrome (HGPS-L; c.1868C>G - p.T623S) associated with farnesylated prelamin A accumulation, or Atypical Progeroid Syndromes (APS; homozygous c.1583C> T - p.T528M; heterozygous c.1762T>C - p.C588R; compound heterozygous c.1583C>T and c.1619T>C - p.T528M and p.M540T) without progerin accumulation. By comparative analysis of the transcriptome and methylome of hiPSC-derived MSCs, we found that patient’s MSCs display specific DNA methylation patterns and modulated transcription at early stages of differentiation. We further explored selected biological processes deregulated in the presence of LMNA variants and confirmed alterations of age-related pathways during MSC differentiation. In particular, we report the presence of an altered mitochondrial pattern, an increased response to double-strand DNA damage and telomere erosion in HGPS, HGPS-L and APS MSCs, suggesting converging pathways, independent of progerin accumulation, but a distinct DNA methylation profile in HGPS and HGPS-L compared to APS cells.
2022-09-12 | GSE202368 | GEO