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Journal of Inherited Metabolic Disease Nov 2015Newborn screening (NBS) is justified if early intervention is effective in a disorder generally not detected early in life on a clinical basis, and if sensitive and... (Review)
Review
Newborn screening (NBS) is justified if early intervention is effective in a disorder generally not detected early in life on a clinical basis, and if sensitive and specific biochemical markers exist. Experience with NBS for homocystinurias and methylation disorders is limited. However, there is robust evidence for the success of early treatment with diet, betaine and/or pyridoxine for CBS deficiency and good evidence for the success of early betaine treatment in severe MTHFR deficiency. These conditions can be screened in dried blood spots by determining methionine (Met), methionine-to-phenylanine (Met/Phe) ratio, and total homocysteine (tHcy) as a second tier marker. Therefore, we recommend NBS for cystathionine beta-synthase and severe MTHFR deficiency. Weaker evidence is available for the disorders of intracellular cobalamin metabolism. Early treatment is clearly of advantage for patients with the late-onset cblC defect. In the early-onset type, survival and non-neurological symptoms improve but the effect on neurocognitive development is uncertain. The cblC defect can be screened by measuring propionylcarnitine, propionylcarnitine-to-acetylcarnitine ratio combined with the second tier markers methylmalonic acid and tHcy. For the cblE and cblG defects, evidence for the benefit of early treatment is weaker; and data on performance of Met, Met/Phe and tHcy even more limited. Individuals homozygous or compound heterozygous for MAT1A mutations may benefit from detection by NBS using Met, which on the other hand also detects asymptomatic heterozygotes. Clinical and laboratory data is insufficient to develop any recommendation on NBS for the cblD, cblF, cblJ defects, glycineN-methyltransferase-, S-adenosylhomocysteinehydrolase- and adenosine kinase deficiency.
Topics: Acetylcarnitine; Betaine; Carnitine; Homocystinuria; Humans; Infant, Newborn; Methionine; Methylation; Methylenetetrahydrofolate Reductase (NADPH2); Methylmalonic Acid; Neonatal Screening; Practice Guidelines as Topic
PubMed: 25762406
DOI: 10.1007/s10545-015-9830-z -
Clinical Epigenetics 2015Current evidence supports the notion that environmental exposures are associated with DNA-methylation and expression changes that can impact human health. Our objective... (Review)
Review
Current evidence supports the notion that environmental exposures are associated with DNA-methylation and expression changes that can impact human health. Our objective was to conduct a systematic review of epidemiologic studies evaluating the association between environmental chemicals with DNA methylation levels in adults. After excluding arsenic, recently evaluated in a systematic review, we identified a total of 17 articles (6 on cadmium, 4 on lead, 2 on mercury, 1 on nickel, 1 on antimony, 1 on tungsten, 5 on persistent organic pollutants and perfluorinated compounds, 1 on bisphenol A, and 3 on polycyclic aromatic hydrocarbons). The selected articles reported quantitative methods to determine DNA methylation including immunocolorimetric assays for total content of genomic DNA methylation, and microarray technologies, methylation-specific quantitative PCR, Luminometric Methylation Assay (LUMA), and bisulfite pyrosequencing for DNA methylation content of genomic sites such as gene promoters, LINE-1, Alu elements, and others. Considering consistency, temporality, strength, dose-response relationship, and biological plausibility, we concluded that the current evidence is not sufficient to provide inference because differences across studies and limited samples sizes make it difficult to compare across studies and to evaluate sources of heterogeneity. Important questions for future research include the need for larger and longitudinal studies, the validation of findings, and the systematic evaluation of the dose-response relationships. Future studies should also consider the evaluation of epigenetic marks recently in the research spotlight such as DNA hydroxymethylation and the role of underlying genetic variants.
PubMed: 25984247
DOI: 10.1186/s13148-015-0055-7 -
Complex Psychiatry 2023Long interspersed nuclear elements (LINEs) are endogenous retrotransposable elements. A few studies have linked the methylation pattern of LINE-1 to different mental... (Review)
Review
INTRODUCTION
Long interspersed nuclear elements (LINEs) are endogenous retrotransposable elements. A few studies have linked the methylation pattern of LINE-1 to different mental disorders (e.g., post-traumatic stress disorder [PTSD], autism spectrum disorder [ASD], panic disorder [PD]). We sought to unify the existing knowledge in the field and provide a better understanding of the association between mental disorders and LINE-1 methylation.
METHODS
A systematic review was executed with 12 eligible articles according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
RESULTS
For psychotic disorders, PTSD, ASD, and PD, lower LINE-1 methylation levels were detected, whereas for mood disorders, the findings are controversial. The studies were conducted with subjects aged 18-80 years. Peripheral blood samples were utilized in 7/12 articles.
CONCLUSION
Although most studies have shown that LINE-1 hypomethylation was associated with mental disorders, there were still some divergences (i.e., hypermethylation associated with mental disorders). These studies suggest that LINE-1 methylation may be an important factor related to the development of mental disorders and highlight the need to better comprehend the biological mechanisms underlying the role of LINE-1 in mental disorders pathophysiology.
PubMed: 37404869
DOI: 10.1159/000530641 -
Archives of Public Health = Archives... Jun 2022Epigenetic changes, especially DNA methylation have a main role in regulating cardiometabolic disorders and their risk factors. This study provides a review of the... (Review)
Review
BACKGROUND
Epigenetic changes, especially DNA methylation have a main role in regulating cardiometabolic disorders and their risk factors. This study provides a review of the current evidence on the association between methylation of some genes (LINE1, ABCG1, SREBF1, PHOSPHO1, ADRB3, and LEP) and cardiometabolic risk factors.
METHODS
A systematic literature search was conducted in electronic databases including Web of Science, PubMed, EMBASE, Google Scholar and Scopus up to end of 2020. All observational human studies (cross-sectional, case-control, and cohort) were included. Studies that assessed the effect of DNA methylation on cardiometabolic risk factors were selected.
RESULTS
Among 1398 articles, eight studies and twenty-one studies were included in the meta-analysis and the systematic review, respectively. Our study showed ABCG1 and LINE1 methylation were positively associated with blood pressure (Fisher's zr = 0.07 (0.06, 0.09), 95% CI: 0.05 to 0.08). Methylation in LINE1, ABCG1, SREBF1, PHOSPHO1 and ADRB3 had no significant association with HDL levels (Fisher's zr = - 0.05 (- 0.13, 0.03), 95% CI:-0.12 to 0.02). Positive association was existed between LINE1, ABCG1 and LEP methylation and LDL levels (Fisher's zr = 0.13 (0.04, 0.23), 95% CI: 0.03 to 0.23). Moreover, positive association was found between HbA1C and ABCG1 methylation (Fisher's zr = 0.11 (0.09, 0.13), 95% CI: 0.09 to 0.12). DNA methylation of LINE1, ABCG1 and SREBF1 genes had no significant association with glucose levels (Fisher's zr = 0.01 (- 0.12, 0.14), 95% CI:-0.12 to 0.14).
CONCLUSION
This meta-analysis showed that DNA methylation was associated with some cardiometabolic risk factors including LDL-C, HbA1C, and blood pressure.
REGISTRATION
Registration ID of the protocol on PROSPERO is CRD42020207677 .
PubMed: 35655232
DOI: 10.1186/s13690-022-00907-1 -
International Journal of Molecular... Aug 2020Despite a number of reports in the literature on the role of epigenetic mechanisms in periodontal disease, a thorough assessment of the published studies is warranted to... (Review)
Review
Despite a number of reports in the literature on the role of epigenetic mechanisms in periodontal disease, a thorough assessment of the published studies is warranted to better comprehend the evidence on the relationship between epigenetic changes and periodontal disease and its treatment. Therefore, the aim of this systematic review is to identify and synthesize the evidence for an association between DNA methylation/histone modification and periodontal disease and its treatment in human adults. A systematic search was independently conducted to identify articles meeting the inclusion criteria. DNA methylation and histone modifications associated with periodontal diseases, gene expression, epigenetic changes after periodontal therapy, and the association between epigenetics and clinical parameters were evaluated. Sixteen studies were identified. All included studies examined DNA modifications in relation to periodontitis, and none of the studies examined histone modifications. Substantial variation regarding the reporting of sample sizes and patient characteristics, statistical analyses, and methodology, was found. There was some evidence, albeit inconsistent, for an association between DNA methylation and periodontal disease. , , , , , and were identified as candidate genes that have been assessed for DNA methylation in periodontitis. While several included studies found associations between methylation levels and periodontal disease risk, there is insufficient evidence to support or refute an association between DNA methylation and periodontal disease/therapy in human adults. Further research must be conducted to identify reproducible epigenetic markers and determine the extent to which DNA methylation can be applied as a clinical biomarker.
Topics: Cyclooxygenase 2; DNA Methylation; Epigenesis, Genetic; Gene Expression Regulation; Genetic Markers; Histone Code; Histones; Humans; Interferon-gamma; Interleukin-6; Periodontal Diseases; Receptors, Interleukin-6; Suppressor of Cytokine Signaling 1 Protein; Tumor Necrosis Factor-alpha
PubMed: 32867386
DOI: 10.3390/ijms21176217 -
Clinical Epigenetics Aug 2023Screening plays a key role in secondary prevention of cervical cancer. High-risk human papillomavirus (hrHPV) testing, a highly sensitive test but with limited... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Screening plays a key role in secondary prevention of cervical cancer. High-risk human papillomavirus (hrHPV) testing, a highly sensitive test but with limited specificity, has become the gold standard frontline for screening programs. Thus, the importance of effective triage strategies, including DNA methylation markers, has been emphasized. Despite the potential reported in individual studies, methylation markers still require validation before being recommended for clinical practice. This systematic review and meta-analysis aimed to evaluate the performance of DNA methylation-based biomarkers for detecting high-grade intraepithelial lesions (HSIL) in hrHPV-positive women.
METHODS
Hence, PubMed, Scopus, and Cochrane databases were searched for studies that assessed methylation in hrHPV-positive women in cervical scrapes. Histologically confirmed HSIL was used as endpoint and QUADAS-2 tool enabled assessment of study quality. A bivariate random-effect model was employed to pool the estimated sensitivity and specificity as well as positive (PPV) and negative (NPV) predictive values.
RESULTS
Twenty-three studies were included in this meta-analysis, from which cohort and referral population-based studies corresponded to nearly 65%. Most of the women analyzed were Dutch, and CADM1, FAM19A4, MAL, and miR124-2 were the most studied genes. Pooled sensitivity and specificity were 0.68 (CI 95% 0.63-0.72) and 0.75 (CI 95% 0.71-0.80) for cervical intraepithelial neoplasia (CIN) 2+ detection, respectively. For CIN3+ detection, pooled sensitivity and specificity were 0.78 (CI 95% 0.74-0.82) and 0.74 (CI 95% 0.69-0.78), respectively. For pooled prevalence, PPV for CIN2+ and CIN3+ detection were 0.514 and 0.392, respectively. Furthermore, NPV for CIN2+ and CIN3+ detection were 0.857 and 0.938, respectively.
CONCLUSIONS
This meta-analysis confirmed the great potential of DNA methylation-based biomarkers as triage tool for hrHPV-positive women in cervical cancer screening. Standardization and improved validation are, however, required. Nevertheless, these markers might represent an excellent alternative to cytology and genotyping for colposcopy referral of hrHPV-positive women, allowing for more cost-effective screening programs.
Topics: Female; Humans; Pregnancy; Uterine Cervical Neoplasms; DNA Methylation; Early Detection of Cancer; Colposcopy; Triage; Papillomavirus Infections; Referral and Consultation; Papillomaviridae; Cell Adhesion Molecule-1
PubMed: 37533074
DOI: 10.1186/s13148-023-01537-2 -
Frontiers in Immunology 2022To summarize the cytokine/chemokine levels of anti-N-methyl-Daspartate receptor encephalitis (NMDAR-E) and explore the potential role of these molecules and immune cells... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
To summarize the cytokine/chemokine levels of anti-N-methyl-Daspartate receptor encephalitis (NMDAR-E) and explore the potential role of these molecules and immune cells in the pathogenic mechanism.
METHODS
The PubMed, Cochrane Library, Embase, and Web of Science databases were searched for various articles that assessed the concentrations of cytokines/chemokines in the unstimulated cerebrospinal fluid (CSF) or serum of patients with NMDAR-E in this systematic review and meta-analysis. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated by Stata17.0.
RESULTS
A total of 19 articles were included in the systematic review from 260 candidate papers, and cytokine/chemokine levels reported in the CSF/serum were examined in each article. This meta-analysis included 17 eligible studies comprising 579 patients with NMDAR-E, 367 patients with noninflammatory neurological disorders, and 42 healthy controls from China, Spain, South Korea, Australia, Czechia, and Sweden. The results indicated that the levels of different cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-10, IL-13, IL-1β, IL-12, and IL-17 and chemokine C-X-C motif ligand (CXCL)10 in the CSF were significantly higher in NMDAR-E patients with a large effect size. In addition, B cell activating factor (BAFF), CXCL13, and interferon (IFN)-γ levels in the CSF were higher in NMDAR-E patients with a middle effect size. In contrast, levels of IL-2 and IL-4 in the CSF and CXCL13 and BAFF in the serum did not show a significant difference between cases and controls.
CONCLUSIONS
These analyses showed that the central immune response in NMDAR-E is a process that involves multiple immune cell interactions mediated by cytokines/chemokines, and T cells play an important role in the pathogenesis of immunity.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/PROSPERO/, identifier (CRD42022342485).
Topics: Humans; Anti-N-Methyl-D-Aspartate Receptor Encephalitis; Chemokines; Cytokines; Interleukin-12; Interleukin-6; Tumor Necrosis Factor-alpha
PubMed: 36761173
DOI: 10.3389/fimmu.2022.1064007 -
PloS One 2017One of the critical mechanisms of gastrointestinal cancer pathogenesis is the silencing of death associated protein kinase 1 (DAPK1), which could be caused by aberrant... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
One of the critical mechanisms of gastrointestinal cancer pathogenesis is the silencing of death associated protein kinase 1 (DAPK1), which could be caused by aberrant methylation of the promoter. However, the relationship between DAPK1 methylation and the risk of gastrointestinal cancer is still controversial. Hence, we conducted this study to determine the potential correlation.
METHODS
Eligible publications were searched in the Pubmed, Embase, and Cochrane Library through November 2016 according to the inclusion criteria and exclusion criteria. Revman 5.3 and Stata 12.0 software were used to analyze the relevant data regarding the association between the frequency of DAPK1 methylation and gastrointestinal cancer.
RESULTS
A total of 22 studies with 2406 patients were included in this meta analysis. Methylation of DAPK1 was positively related with the risk of gastrointestinal cancer (odds ratio [OR] = 5.35, 95% confidence interval [CI]: 2.76-10.38, P<0.00001, random effects model). The source of heterogeneity was analyzed by sensitivity analysis and subgroup analysis. After omitting one heterogeneous study, the I2 decreased and the OR increased in pooled analysis. Also, the heterogeneity decreased most significantly in the subgroup of studies that had a sample size of less than 60 cases. Then, the correlations between DAPK1 methylation and clinicopathological features of gastrointestinal cancer were assessed. DAPK1 methylation was positively correlated with the lymph node (N) stage (positive vs. negative, OR = 1.45, 95%CI: 1.01-2.06, P = 0.04, fixed effects model) and poor differentiation (OR = 1.55, 95%CI: 1.02-2.35, P = 0.04, fixed effects model) in gastric cancer, and the association was significant among Asian patients. However, among cases of gastrointestinal cancer, the association between DAPK1 methylation and tumor (T) stage, N stage, distant metastasis (M) stage, and cancer differentiation were not statistically significant.
CONCLUSIONS
DAPK1 methylation is a potential biomarker for the early diagnosis of gastrointestinal cancer. Further analysis of the clinicopathological features indicated that aberrant methylation of DAPK1 is positively associated with the tumorigenesis of gastrointestinal cancer, and metastasis of gastric cancer.
Topics: DNA Methylation; Death-Associated Protein Kinases; Gastrointestinal Neoplasms; Gene Expression Regulation, Neoplastic; Genetic Predisposition to Disease; Humans; Risk Factors
PubMed: 28934284
DOI: 10.1371/journal.pone.0184959 -
Genes, Brain, and Behavior Mar 2020The integration of behavioral epigenetics' principles (eg, DNA methylation) into the study of human infants' development has mainly focused on the effects of early...
The integration of behavioral epigenetics' principles (eg, DNA methylation) into the study of human infants' development has mainly focused on the effects of early adverse exposures, paying less attention to protective caregiving experiences. The present review focused on DNA methylation linked to variations in maternal behavior in human infants and children. Literature search occurred on three databases (PubMed, Scopus and Web of Science) and 11 records were selected. Key variables were abstracted from each article including: sample size and characteristics, time and type of maternal caregiving behavior exposure, time and locus of methylation biomarker, presence/absence, time and type of adverse exposure. Six out of eleven records documented the predictive effect of maternal caregiving on DNA methylation, whereas the remaining five reported on the role of maternal behavior as an influencing factor of the adversity-to-methylation link. Consistent with evidence from the animal model, the quality of maternal caregiving in humans (a) might be associated with variations in DNA methylation status of specific genes involved in socio-emotional development and (b) might partially buffer the association between early adversities and epigenetic variations in infants and children. Current evidence suggests that the quality of maternal caregiving can contribute to behavioral development trajectories of human infants and children at least partially through epigenetic regulation. Open questions and methodological aspects are discussed to guide future human developmental research in behavioral epigenetics.
Topics: Child; Child, Preschool; DNA Methylation; Epigenome; Female; Humans; Infant; Infant, Newborn; Maternal Behavior; Mother-Child Relations; Quantitative Trait Loci
PubMed: 31622002
DOI: 10.1111/gbb.12616 -
Journal of Crohn's & Colitis Mar 2023Over the past decade, the DNA methylome has been increasingly studied in peripheral blood of inflammatory bowel disease [IBD] patients. However, a comprehensive summary... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND AIMS
Over the past decade, the DNA methylome has been increasingly studied in peripheral blood of inflammatory bowel disease [IBD] patients. However, a comprehensive summary and meta-analysis of peripheral blood leukocyte [PBL] DNA methylation studies has thus far not been conducted. Here, we systematically reviewed all available literature up to February 2022 and summarized the observations by means of meta-analysis.
METHODS
We conducted a systematic search and critical appraisal of IBD-associated DNA methylation studies in PBL using the biomarker-based cross-sectional studies [BIOCROSS] tool. Subsequently, we performed meta-analyses on the summary statistics obtained from epigenome-wide association studies [EWAS] that included patients with Crohn's disease [CD], ulcerative colitis [UC] and/or healthy controls [HC].
RESULTS
Altogether, we included 15 studies for systematic review. Critical appraisal revealed large methodological and outcome heterogeneity between studies. Summary statistics were obtained from four studies based on a cumulative 552 samples [177 CD, 132 UC and 243 HC]. Consistent differential methylation was identified for 256 differentially methylated probes [DMPs; Bonferroni-adjusted p ≤ 0.05] when comparing CD with HC and 103 when comparing UC with HC. Comparing IBD [CD + UC] with HC resulted in 224 DMPs. Importantly, several of the previously identified DMPs, such as VMP1/TMEM49/MIR21 and RPS6KA2, were consistently differentially methylated across all studies.
CONCLUSION
Methodological homogenization of IBD epigenetic studies is needed to allow for easier aggregation and independent validation. Nonetheless, we were able to confirm previous observations. Our results can serve as the basis for future IBD epigenetic biomarker research in PBL.
Topics: Humans; DNA Methylation; Cross-Sectional Studies; Inflammatory Bowel Diseases; Crohn Disease; Colitis, Ulcerative; Membrane Proteins
PubMed: 35998097
DOI: 10.1093/ecco-jcc/jjac119