Search results for "HYPOMETHYLATION"

showing 7 items of 17 documents

Losing DNA methylation at repetitive elements and breaking bad

2021

Abstract Background DNA methylation is an epigenetic chromatin mark that allows heterochromatin formation and gene silencing. It has a fundamental role in preserving genome stability (including chromosome stability) by controlling both gene expression and chromatin structure. Therefore, the onset of an incorrect pattern of DNA methylation is potentially dangerous for the cells. This is particularly important with respect to repetitive elements, which constitute the third of the human genome. Main body Repetitive sequences are involved in several cell processes, however, due to their intrinsic nature, they can be a source of genome instability. Thus, most repetitive elements are usually meth…

EpigenomicsGenome instabilityHeterochromatinSatellitesReviewRepetitive DNABiologyQH426-47003 medical and health sciencesLINE-10302 clinical medicineDNA hypomethylationGeneticsHumansEpigeneticsAutism spectrum disorderRepeated sequenceMolecular BiologyRepetitive Sequences Nucleic Acid030304 developmental biologyCancerGenetics0303 health sciencesHereditary diseasesDNA MethylationChromatinChromatinSettore BIO/18 - GeneticaLong Interspersed Nucleotide ElementsICF syndromeDNA methylationHuman genomeAlzheimer’s disease030217 neurology & neurosurgeryNeuropsychiatric disordersDNA hypomethylationEpigenetics & Chromatin
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Obesogen effect of bisphenol S alters mRNA expression and DNA methylation profiling in male mouse liver

2020

International audience; Environmental pollution is increasingly considered an important factor involved in the obesity incidence. Endocrine disruptors (EDs) are important actors in the concept of DOHaD (Developmental Origins of Health and Disease), where epigenetic mechanisms play crucial roles. Bisphenol A (BPA), a monomer used in the manufacture of plastics and resins is one of the most studied obesogenic endocrine disruptor. Bisphenol S (BPS), a BPA substitute, has the same obesogenic properties, acting at low doses with a sex-specific effect following perinatal exposure. Since the liver is a major organ in regulating body lipid homeostasis, we investigated gene expression and DNA methyl…

Malemedicine.medical_specialtyEnvironmental EngineeringHealth Toxicology and Mutagenesis[SDV]Life Sciences [q-bio]0208 environmental biotechnologyEnvironmental pollution02 engineering and technologyEndocrine Disruptors010501 environmental sciencesBiology01 natural sciencesEpigenesis GeneticPhenolsPregnancyInternal medicineToxicity TestsGene expressionmedicineAnimalsHumansEnvironmental ChemistryObesityRNA MessengerSulfonesEpigeneticsGene0105 earth and related environmental sciencesDose-Response Relationship DrugPublic Health Environmental and Occupational HealthGeneral MedicineGeneral ChemistryDNA MethylationLipid MetabolismPollution3. Good health020801 environmental engineeringMice Inbred C57BLEndocrinologyGene Expression RegulationLiverEndocrine disruptorPrenatal Exposure Delayed EffectsDNA methylationFemaleObesogenhormones hormone substitutes and hormone antagonistsDNA hypomethylation
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Histone Variant MacroH2A1 Marks Liver Aging and Orchestrates the Escape from Senescence Induced by DNA Hypomethylation in Hepatocellular Carcinoma

2015

The epigenetic basis of age-associated progression of liver diseases towards hepatocellular carcinoma (HCC) is unclear. MacroH2A1 is a variant of histone H2A1, present in the two isoforms, with fundamental roles in cell homeostasis. MacroH2A1 is a marker of senescence associated heterochromatic foci (SAHF) and synergizes with DNA demethylating chemotherapic agent 5-aza-2'-deoxycytidine (5-aza-dC) in silencing tumor suppressor genes in human fibroblasts. We show that protein levels of macroH2A1 isoforms are increased in the livers of old rodents and humans, and in human HCC tissue. Human HCC cells overexpressing macroH2A1 escape a 5-aza-dC-induced senescent phenotype, as determined by cell p…

SenescencebiologyCell growthCell cycleBiochemistryCell biologyHistoneGeneticsbiology.proteinGene silencingEpigeneticsMolecular BiologyGeneBiotechnologyDNA hypomethylation
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Global DNA Hypomethylation following 5-aza-2'-deoxycytidine treatment induces aneuploidy in HCT-116 tumor cells.

2013

Aneuploidy, the alteration of the normal number of chromosomes, is found in most of the human solid tumors and correlated with to defects in the process of chromosome segregation (1). It was also suggested that the alteration of the 5-methylcytosine (5-mC) pattern in the chromosome pericentromeric region, generated to aneuploid cells (2, 3). To investigate the relationship between hypomethylation and whole chromosome aneuploidy, we treated HCT-116 cells, a near diploid line, with the demethylating agent 5-aza- 2'-deoxycytidine (DAC). The treatment with DAC for 24, 48 and 72 hours produced a progressive reduction of DNA methylation as shown by decrease of 5-mC signal. DNA hypomethylation res…

Settore BIO/18 - GeneticaDNA hypomethylation aneuploidy
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Metilazione del DNA in artrite reumatoide

2005

Lo stato di metilazione del DNA genomico e del gene PTHrP è stato valutato con tecniche molecolari e citogenetiche in artrite reumatoide (AR), patologia autoimmune caratterizzata anche da alta incidenza di linfomi e da ipercalcemia per overespressione del gene PTHrP. La metilazione del DNA, infatti, ha un ruolo critico nello sviluppo delle malattie neoplastiche; il gene PTHrP avendo tre promotori uno dei quali contiene un’isola CpG è un buon candidato per la deregolazione da alterato pattern di metilazione locale. Le indagini sulla metilazione genomica, condotte su DNA estratto da sangue periferico di pazienti e di donatori e amplificato in reazioni di Methylation-Sensitive Arbitrarily Prim…

Settore BIO/18 - Geneticainstead chromosomes of controls were almost uniformly decorated by brilliant grains. Studies on methylation of PTHrP gene promoter 2 performed on five CpG island internal sites using the Methylation-Sensitive Restriction Endonuclease Multiplex (MSREM)-PCR showed that one of the sites nearest the trascription starting point is heavy methylated in a significantly high number of RA patients. Thus RA seems to be characterized by genomewide hypomethylation associated with local hypermethylation like the most part of tumors. This result raises the possibility that susceptibility to lymphomas is related to abnormal DNA methylation levels and suggests the opportunity to evaluate the DNA methylation status in RA patientin fact the demethylating therapies together with diet and life style can act towards an increase of tumor risk. Future studies using a larger number of subjects could confirm these findings.Rheumatoid Arthritis (RA) is a chronic multisystem inflammatory disease characterized by high recurrence of lymphomas as well as hypercalcemia due to PTHrP overexpression. Because of DNA methylation plays a critical role in development of neoplasias we determined in RA patients the global DNA methylation status and local methylation pattern of the CpG island of one of the three promoters of PTHrP gene utilizing molecular and cytogenetic techniques. Investigations performed on DNA from peripheral blood of patients and donors amplified by Methylation-Sensitive Arbitrarily Primed (MeS-AP)-PCR indicated that RA is strongly associated with global DNA hypomethylation. Similarly chromosomal DNA methylation pattern analysis by indirect immunofluorescence technique with anti 5-methylcitosine antibody showed all peripheral lymphocyte metaphases from RA patients with chromosomes weakly fluorescent without discrete grain
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NFATc1 Is Transcriptionally Activated in Chronic Lymphocytic Leukemia (CLL) By Promotor DNA-Hypomethylation Which Correlates with in-Vitro Vulnerabil…

2014

Abstract Chronic lymphocytic leukemia (CLL), the most frequent adult leukemia in Western countries, is characterized by progressive accumulation of mature, monoclonal B lymphocytes in blood, bone marrow, and lymphoid tissues. In the pathogenesis and treatment of CLL, B cell receptor (BCR) signaling plays a crucial role, and aberrations in downstream pathways that become activated in CLL need to be better defined. One downstream target of BCR signaling is NFATc1, a transcription factor with a high oncogenic and transforming potential. Employing a genome-wide comparative DNA methylation analysis the NFATc1 5’ region was identified to be DNA hypomethylated in CLL patient samples. The pilot ser…

biologyChronic lymphocytic leukemiaImmunologyB-cell receptorbreakpoint cluster regionPromoterCell BiologyHematologymedicine.diseaseBiochemistryCD19Leukemiahemic and lymphatic diseasesDNA methylationmedicineCancer researchbiology.proteinDNA hypomethylationBlood
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Genomewide hypomethylation and PTHrP gene hypermethylation as a model for the prediction of cancer risk in rheumatoid arthritis

2007

We have previously shown that PTHrP(38-94)-amide restrains growth and invasion "in vitro", causes striking toxicity and accelerates death of some breast cancer cell lines, the most responsive being MDA-MB231 whose tumorigenesis was also attenuated "in vivo". PTHrP(38-94)-amide contains the domain implicated in the nuclear import of PTHrP. Although the nucleus was identified as a destination for mid-region PTHrP, evidence for direct DNA-binding capability is lacking to date. Here, we examined the localization of PTHrP(38-94)-amide within MDA-MB231 cells and within metaphase spread preparations and characterized its DNA-binding properties, employing a combination of immunocytochemical, cytoge…

hypomethylation cancer risk rheumatoid arthritis
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