Arsenic methylation and microbial communities in paddy soils under alternating anoxic and oxic conditions.

Arsenic (As) methylation in soils affects the environmental behavior of As, excessive accumulation of dimethylarsenate (DMA) in rice plants leads to straighthead disease and a serious drop in crop yield. Understanding the mobility and transformation of methylated arsenic in redox-changing paddy fields is crucial for food security. Here, soils including un-arsenic contaminated (N-As), low-arsenic (L-As), medium-arsenic (M-As), and high-arsenic (H-As) soils were incubated under continuous anoxic, continuous oxic, and consecutive anoxic/oxic treatments respectively, to profile arsenic methylating process and microbial species involved in the As cycle. Under anoxic-oxic (A-O) treatment, methylated arsenic was significantly increased once oxygen was introduced into the incubation system. The methylated arsenic concentrations were up to 2-24 times higher than those in anoxic (A), oxic (O), and oxic-anoxic (O-A) treatments, under which arsenic was methylated slightly and then decreased in all four As concentration soils. In fact, the most plentiful arsenite S-adenosylmethionine methyltransferase genes (arsM) contributed to the increase in As methylation. Proteobacteria (40.8%-62.4%), Firmicutes (3.5%-15.7%), and Desulfobacterota (5.3%-13.3%) were the major microorganisms related to this process. These microbial increased markedly and played more important roles after oxygen was introduced, indicating that they were potential keystone microbial groups for As methylation in the alternating anoxic (flooding) and oxic (drainage) environment. The novel findings provided new insights into the reoxidation-driven arsenic methylation processes and the model could be used for further risk estimation in periodically flooded paddy fields.

Identification and functional characterisation of DNA methylation differences between East- and West-originating Finns.

Eastern and Western Finns show a striking difference in coronary heart disease-related mortality; genetics is a known contributor for this discrepancy. Here, we discuss the potential role of DNA methylation in mediating the discrepancy in cardiometabolic disease-risk phenotypes between the sub-populations. We used data from the Young Finns Study (n = 969) to compare the genome-wide DNA methylation levels of East- and West-originating Finns. We identified 21 differentially methylated loci (FDR < 0.05; Δß >2.5%) and 7 regions (smoothed FDR < 0.05; CpGs ≥ 5). Methylation at all loci and regions associates with genetic variants (p < 5 × 10-8). Independently of genetics, methylation at 11 loci and 4 regions associates with transcript expression, including genes encoding zinc finger proteins. Similarly, methylation at 5 loci and 4 regions associates with cardiometabolic disease-risk phenotypes including triglycerides, glucose, cholesterol, as well as insulin treatment. This analysis was also performed in LURIC (n = 2371), a German cardiovascular patient cohort, and results replicated for the association of methylation at cg26740318 and DMR_11p15 with diabetes-related phenotypes and methylation at DMR_22q13 with triglyceride levels. Our results indicate that DNA methylation differences between East and West Finns may have a functional role in mediating the cardiometabolic disease discrepancy between the sub-populations.

Zuogui Pills Improve the Learning and Memory Ability of Brain-Aging Mice through the Estrogen Receptor ERα Methylation Pathway.

INTRODUCTION: Sex hormones are important factors in maintaining brain function and acting as brain protectors. Recent research suggests that neuronal damage in brain aging may be linked to the methylation of the estrogen receptor α (ERα). However, the mechanism of Zuogui Pills (ZGW) in brain-aging ERα DNA methylation and neuronal repair remains unknown. MATERIALS AND METHODS: D-galactose-induced ovary removal mice were used as a model of aging. Changes in estrous cycle were detected in mice by vaginal cell smear. Animal behavior tests, including the Morris water maze (MWM) and new object recognition (NOR) test, were conducted. Hematoxylin-eosin (HE) and Nissl-staining were carried out to assess hippocampal neurogenesis. Enzyme-linked immunosorbent assay (ELISA) was performed for 5- methylcytosine methylation levels, and immunohistochemistry (IHC) and western blotting (WB) experiments were performed to assess ERα/DNA methyltransferase 1 (DNMT1) expression after ZGW treatment. Finally, bisulfite sequencing PCR (BSP) analysis was performed to identify methylated differentially expressed estrogen receptor 1 (ESR1) gene in D-gal-induced senescent neurons before and after ZGW treatment. RESULTS: We found that ERα methylation was involved in the delayed brain ageing process of ZGW. Mechanistically, ZGW can improve the learning and memory ability of brain-aging mice, reduce the expression of 5-methylcytosine (5-mc) in serum, increase the amount of ERα, inhibit the expression of DNMT1, and significantly reduce methylated expression of the ESRI gene. CONCLUSION: Our data suggested that ZGW slowed down D-gal-induced brain aging in mice, and these results showed that ZGW is beneficial for aging. It may be used for neuronal protection in aging.

Uncovering novel regulatory variants in carbohydrate metabolism: a comprehensive multi-omics study of glycemic traits in the Indian population.

Clinical biomarkers such as fasting glucose, HbA1c, and fasting insulin, which gauge glycemic status in the body, are highly influenced by diet. Indians are genetically predisposed to type 2 diabetes and their carbohydrate-centric diet further elevates the disease risk. Despite the combined influence of genetic and environmental risk factors, Indians have been inadequately explored in the studies of glycemic traits. Addressing this gap, we investigate the genetic architecture of glycemic traits at genome-wide level in 4927 Indians (without diabetes). Our analysis revealed numerous variants of sub-genome-wide significance, and their credibility was thoroughly assessed by integrating data from various levels. This identified key effector genes, ZNF470, DPP6, GXYLT2, PITPNM3, BEND7, and LORICRIN-PGLYRP3. While these genes were weakly linked with carbohydrate intake or glycemia earlier in other populations, our findings demonstrated a much stronger association in the Indian population. Associated genetic variants within these genes served as expression quantitative trait loci (eQTLs) in various gut tissues essential for digestion. Additionally, majority of these gut eQTLs functioned as methylation quantitative trait loci (meth-QTLs) observed in peripheral blood samples from 223 Indians, elucidating the underlying mechanism of their regulation of target gene expression. Specific co-localized eQTLs-meth-QTLs altered the binding affinity of transcription factors targeting crucial genes involved in glucose metabolism. Our study identifies previously unreported genetic variants that strongly influence the diet-glycemia relationship. These findings set the stage for future research into personalized lifestyle interventions integrating genetic insights with tailored dietary strategies to mitigate disease risk based on individual genetic profiles.

Evaluation of Fibroblast Growth Factor Receptor 3 (FGFR3) and Tumor Protein P53 (TP53) as Independent Prognostic Biomarkers in High-Grade Non-muscle Invasive Bladder Cancer.

Introduction Bladder cancer is a significant health issue with an increased recurrence and progression rate, requiring invasive follow-up, which shows a poor prognosis. In addition, the prognostic role of mutant fibroblast growth factor receptor 3 (FGFR3) and tumor protein P53 (TP53) is controversial; therefore, we investigated the methylation status and their altered gene expression in low- and high-grade non-muscle-invasive bladder cancer (NMIBC) subjects. Materials and methods This case-control study was conducted between 2020 and 2023, in which n = 115 tumor tissues (NMIBC n = 85) and (controls n = 30) were examined for FGFR3 and FGFR promoter methylation and expression using methylation-specific PCR (MSP) and real-time PCR. The multivariate regression analysis and Kaplan-Meier (KM) plots were used to establish the association of FGFR3 and TP53 with clinicopathological features and survival outcomes of NMIBC patients. Results High-grade NMIBC tumors showed substantial methylation patterns, with TP53 hypomethylated (p = 0.034) and FGFR3 hypermethylated (p = 0.046), as well as significant mRNA expression of Tp53 and FGFR3 (p = 0.001). The multivariate analysis shows FGFR3 and Tp53 were associated with recurrence-free survival with sensitivity (p = 0.045 (78%); 0.034 (70.7%)) and progression-free survival (p = 0.022(61.5%); 0.038 (69.2%)).  Conclusion The findings of this investigation indicate that FGFR3 hypermethylation and TP53 hypomethylation are independent prognostic indicators that aid in the evaluation of disease outcomes in high-grade NMIBC tumors.

Racial distribution of molecularly classified brain tumors.

Background: In many cancers, specific subtypes are more prevalent in specific racial backgrounds. However, little is known about the racial distribution of specific molecular types of brain tumors. Public data repositories lack data on many brain tumor subtypes as well as diagnostic annotation using the current World Health Organization classification. A better understanding of the prevalence of brain tumors in different racial backgrounds may provide insight into tumor predisposition and development, and improve prevention. Methods: We retrospectively analyzed the racial distribution of 1709 primary brain tumors classified by their methylation profiles using clinically validated whole genome DNA methylation. Self-reported race was obtained from medical records. Our cohort included 82% White, 10% Black, and 8% Asian patients with 74% of patients reporting their race. Results: There was a significant difference in the racial distribution of specific types of brain tumors. Blacks were overrepresented in pituitary adenomas (35%, P < .001), with the largest proportion of FSH/LH subtype. Whites were underrepresented at 47% of all pituitary adenoma patients (P < .001). Glioblastoma (GBM) IDH wild-type showed an enrichment of Whites, at 90% (P < .001), and a significantly smaller percentage of Blacks, at 3% (P < .001). Conclusions: Molecularly classified brain tumor groups and subgroups show different distributions among the three main racial backgrounds suggesting the contribution of race to brain tumor development.

Epigenetic insights into Fragile X Syndrome.

Fragile X Syndrome (FXS) is a genetic neurodevelopmental disorder closely associated with intellectual disability and autism spectrum disorders. The core of the disease lies in the abnormal expansion of the CGG trinucleotide repeat sequence at the 5'end of the FMR1 gene. When the repetition exceeds 200 times, it causes the silencing of the FMR1 gene, leading to the absence of the encoded Fragile X mental retardation protein 1 (FMRP). Although the detailed mechanism by which the CGG repeat expansion triggers gene silencing is yet to be fully elucidated, it is known that this process does not alter the promoter region or the coding sequence of the FMR1 gene. This discovery provides a scientific basis for the potential reversal of FMR1 gene silencing through interventional approaches, thereby improving the symptoms of FXS. Epigenetics, a mechanism of genetic regulation that does not depend on changes in the DNA sequence, has become a new focus in FXS research by modulating gene expression in a reversible manner. The latest progress in molecular genetics has revealed that epigenetics plays a key role in the pathogenesis and pathophysiological processes of FXS. This article compiles the existing research findings on the role of epigenetics in Fragile X Syndrome (FXS) with the aim of deepening the understanding of the pathogenesis of FXS to identify potential targets for new therapeutic strategies.

Current Updates on the Understanding of the Role of DNA Methylation on Obesity.

Obesity is a condition in which there is an accumulation of excess body fat leading to a weight far above the normal range that poses significant health risks. According to WHO, 8 billion people in the world were obese in 2022. Consequently, obesity has become a pandemic with negative impacts on both global health and economies. Obesity is influenced by various factors including environmental influences, lifestyle choices, gut microbiota, genetic factors, and epigenetic mechanisms such as DNA methylation. DNA methylation can affect an individual's phenotype and condition without altering their DNA sequence. It is the most extensively studied epigenetic alteration and it plays an important part in controlling gene activity associated with obesity. Numerous studies have indicated that DNA methylation is implicated in obesity, thus this review aims to elaborate the roles of DNA methylation to inform the development of preventive measures for obesity.

Causal association between epilepsy and its DNA methylation profile and atrial fibrillation.

BACKGROUND: The "epileptic heart" concept is emerging, but the causal relationship between epilepsy and atrial fibrillation (AF) remains unclarified. OBJECTIVE: This study explores the genetic correlations and bidirectional causality between various epilepsy phenotypes and AF. METHODS: Genome-wide association study (GWAS) statistics for 10 epilepsy subtypes (29,944 cases, 52,538 controls) and AF (60,620 cases, 970,216 controls) were sourced from the International League Against Epilepsy (ILAE) and HGRI-EBI Catalog-GWAS, respectively. Linkage disequilibrium score regression (LDSC) and genome-wide Mendelian Randomization (MR) evaluated genetic correlations and bidirectional causal relationships. Epilepsy-related DNA methylation data (N= ∼800) from EWAS catalog were analyzed to identify causal CpG sites influencing AF risk through epigenetic MR. RESULTS: LDSC revealed significant genetic correlations between four epilepsy subtypes and AF (rg from 0.116 to 0.241). Forward MR suggested a significant causal effect of focal epilepsy with hippocampal sclerosis (FE with HS) on AF risk (IVW and MR-PRESSO: OR = 1.046, P ≤ 0.004), with results robust against heterogeneity, horizontal pleiotropy, and outliers. Epigenetic MR indicated that lower methylation at cg06222062 (OR = 0.994, P = 3.16E-04) mapped to PLA2G5 and cg08461451 mapped to SPPL2B gene (OR = 0.954, P = 1.19E-03), and higher cg10541930 in the C10orf143 promoter (OR = 1.043, P = 4.18E-22) increases AF risk. Sensitivity analyses affirmed no pleiotropic bias. CONCLUSION: FE with HS significantly increases AF risk, highlighting the natural neural-cardiac connection and the need for cardiac monitoring in epilepsy patients. Specific methylated CpG sites may serve as biomarkers and preventive targets for AF susceptibility.

Biomarkers differentiating regression from progression among untreated cervical intraepithelial neoplasia grade 2 lesions.

BACKGROUND: Cervical intraepithelial neoplasia grade 2 (CIN2) is one of the precursor stages before cervical lesions develop into cervical cancer. The spontaneous development of CIN2 is ambiguous. One part of CIN2 lesions will progress to cervical intraepithelial neoplasia grade 3 or worse (CIN3+), another part will regress to cervical intraepithelial neoplasia grade 1 or less (CIN1-), and the last part will persist. Although the guidelines suggest that CIN2 patients with fertility requirements can be treated conservatively to minimize the risk of infertility and obstetric complications, most CIN2 patients undergo surgical treatment to prevent the progression of the disease, which will lead to over-treatment and unnecessary complications. AIM OF REVIEW: The clinical outcome of CIN2 lesions is unpredictable and depends on histopathological examinations. Thus, it is necessary to identify the biomarkers differentiating regression lesions from progression lesions, which is conducive to supporting individualised treatment. The natural history of CIN2 is commonly regulated by the interaction of human papillomavirus (HPV) viral factors (HPV genotype and viral DNA methylation), host factors (p16/Ki-67 status, host gene methylation effects, human leukocyte antigen subtypes and immune microenvironment) and other factors (vaginal microbiota). KEY SCIENTIFIC CONCEPTS OF REVIEW: This review summarized the biomarkers predicting the spontaneous regression of CIN2, which correlated with HPV infection, the (epi)genetic change of host genes and microenvironment change. However, potential biomarkers must be validated with prospective cohort studies, which should be conducted with expanded enrollment, a longer observational period and the tracking of more patients.

Development of a rapid mass spectrometric method for the analysis of ten-eleven translocation enzymes.

In DNA, methylation at the fifth position of cytosine (5mC) by DNA methyltransferases is essential for eukaryotic gene regulation. Methylation patterns are dynamically controlled by epigenetic machinery. Erasure of 5mC by Fe2+ and 2-ketoglutarate (2KG) dependent dioxygenases in the ten-eleven translocation family (TET1-3), plays a key role in nuclear processes. Through the event of active demethylation, TET proteins iteratively oxidize 5mC to 5-hydroxymethyl cytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxycytosine (5caC), each of which has been implicated in numerous diseases when aberrantly generated. A wide range of biochemical assays have been developed to characterize TET activity, many of which require multi-step processing to detect and quantify the 5mC oxidized products. Herein, we describe the development and optimization of a sensitive MALDI mass spectrometry-based technique that directly measures TET activity and eliminates tedious processing steps. Employing optimized assay conditions, we report the steady-state activity of wild type TET2 enzymes to furnish 5hmC, 5fC and 5caC. We next determine IC50 values of several small-molecule inhibitors of TETs. The utility of this assay is further demonstrated by analyzing the activity of V1395A which is an activating mutant of TET2 that primarily generates 5caC. Lastly, we describe the development of a secondary assay that utilizes bisulfite chemistry to further examine the activity of wildtype TET2 and V1395A in a base-resolution manner. The combined results demonstrate that the activity of TET proteins can be gauged, and their products accurately quantified using our methods.

ß-glucans, SAM, and GSH fluctuations in barley anther tissue culture conditions affect regenerants' DNA methylation and GPRE.

BACKGROUND: Microspore embryogenesis is a process that produces doubled haploids in tissue culture environments and is widely used in cereal plants. The efficient production of green regenerants requires stresses that could be sensed at the level of glycolysis, followed by the Krebs cycle and electron transfer chain. The latter can be affected by Cu(II) ion concentration in the induction media acting as cofactors of biochemical reactions, indirectly influencing the production of glutathione (GSH) and S-adenosyl-L-methionine (SAM) and thereby affecting epigenetic mechanisms involving DNA methylation (demethylation-DM, de novo methylation-DNM). The conclusions mentioned were acquired from research on triticale regenerants, but there is no similar research on barley. In this way, the study looks at how DNM, DM, Cu(II), SAM, GSH, and ß-glucan affect the ability of green plant regeneration efficiency (GPRE). RESULTS: The experiment involved spring barley regenerants obtained through anther culture. Nine variants (trials) of induction media were created by adding copper (CuSO4: 0.1; 5; 10 µM) and silver salts (AgNO3: 0; 10; 60 µM), with varying incubation times for the anthers (21, 28, and 35 days). Changes in DNA methylation were estimated using the DArTseqMet molecular marker method, which also detects cytosine methylation. Phenotype variability in ß-glucans, SAM and GSH induced by the nutrient treatments was assessed using tentative assignments based on the Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. The effectiveness of green plant regeneration ranged from 0.1 to 2.91 plants per 100 plated anthers. The level of demethylation ranged from 7.61 to 32.29, while de novo methylation reached values ranging from 6.83 to 32.27. The paper demonstrates that the samples from specific in vitro conditions (trials) formed tight groups linked to the factors contributing to the two main components responsible for 55.05% of the variance (to the first component DNM, DM, to the second component GSH, ß-glucans, Cu(II), GPRE). CONCLUSIONS: We can conclude that in vitro tissue culture conditions affect biochemical levels, DNA methylation changes, and GPRE. Increasing Cu(II) concentration in the IM impacts the metabolism and DNA methylation, elevating GPRE. Thus, changing Cu(II) concentration in the IM is fair to expect to boost GPRE.

Universal penalized regression (Elastic-net) model with differentially methylated promoters for oral cancer prediction.

BACKGROUND: DNA methylation showed notable potential to act as a diagnostic marker in many cancers. Many studies proposed DNA methylation biomarker in OSCC detection, while most of these studies are limited to specific cohorts or geographical location. However, the generalizability of DNA methylation as a diagnostic marker in oral cancer across different geographical locations is yet to be investigated. METHODS: We used genome-wide methylation data from 384 oral cavity cancer and normal tissues from TCGA HNSCC and eastern India. The common differentially methylated CpGs in these two cohorts were used to develop an Elastic-net model that can be used for the diagnosis of OSCC. The model was validated using 812 HNSCC and normal samples from different anatomical sites of oral cavity from seven countries. Droplet Digital PCR of methyl-sensitive restriction enzyme digested DNA (ddMSRE) was used for quantification of methylation and validation of the model with 22 OSCC and 22 contralateral normal samples. Additionally, pyrosequencing was used to validate the model using 46 OSCC and 25 adjacent normal and 21 contralateral normal tissue samples. RESULTS: With ddMSRE, our model showed 91% sensitivity, 100% specificity, and 95% accuracy in classifying OSCC from the contralateral normal tissues. Validation of the model with pyrosequencing also showed 96% sensitivity, 91% specificity, and 93% accuracy for classifying the OSCC from contralateral normal samples, while in case of adjacent normal samples we found similar sensitivity but with 20% specificity, suggesting the presence of early disease methylation signature at the adjacent normal samples. Methylation array data of HNSCC and normal tissues from different geographical locations and different anatomical sites showed comparable sensitivity, specificity, and accuracy in detecting oral cavity cancer with across. Similar results were also observed for different stages of oral cavity cancer. CONCLUSIONS: Our model identified crucial genomic regions affected by DNA methylation in OSCC and showed similar accuracy in detecting oral cancer across different geographical locations. The high specificity of this model in classifying contralateral normal samples from the oral cancer compared to the adjacent normal samples suggested applicability of the model in early detection.

Genome-wide characterization of dynamic DNA 5-hydroxymethylcytosine and TET2-related DNA demethylation during breast tumorigenesis.

BACKGROUND: Breast tumorigenesis is a complex and multistep process accompanied by both genetic and epigenetic dysregulation. In contrast to the extensive studies on DNA epigenetic modifications 5-hydroxymethylcytosine (5hmC) and 5-methylcytosine (5mC) in malignant breast tumors, their roles in the early phases of breast tumorigenesis remain ambiguous. RESULTS: DNA 5hmC and 5mC exhibited a consistent and significant decrease from usual ductal hyperplasia to atypical ductal hyperplasia and subsequently to ductal carcinoma in situ (DCIS). However, 5hmC showed a modest increase in invasive ductal breast cancer compared to DCIS. Genomic analyses showed that the changes in 5hmC and 5mC levels occurred around the transcription start sites (TSSs), and the modification levels were strongly correlated with gene expression levels. Meanwhile, it was found that differentially hydroxymethylated regions (DhMRs) and differentially methylated regions (DMRs) were overlapped in the early phases and accompanied by the enrichment of active histone marks. In addition, TET2-related DNA demethylation was found to be involved in breast tumorigenesis, and four transcription factor binding sites (TFs: ESR1, FOXA1, GATA3, FOS) were enriched in TET2-related DhMRs/DMRs. Intriguingly, we also identified a certain number of common DhMRs between tumor samples and cell-free DNA (cfDNA). CONCLUSIONS: Our study reveals that dynamic changes in DNA 5hmC and 5mC play a vital role in propelling breast tumorigenesis. Both TFs and active histone marks are involved in TET2-related DNA demethylation. Concurrent changes in 5hmC signals in primary breast tumors and cfDNA may play a promising role in breast cancer screening.

An epigenome-wide study of a needs-based family intervention for offspring of trauma-exposed mothers in Kosovo.

INTRODUCTION: Maternal stress and trauma during pregnancy have been shown to influence cortisol levels and epigenetic patterns, including DNA methylation, in the offspring. This study aimed to determine whether a tailor-made family intervention could help reduce cortisol levels in children born to traumatized mothers, and to determine whether it effected offspring DNA methylation. The secondary aim was to determine whether the family intervention influenced DNA methylation aging, a marker of biological aging. METHODS: A needs-based family intervention was designed to help address relational difficulties and family functioning, and included a focus on family strengths and problem-solving patterns. Women survivors of sexual violence during the Kosovar war in 1998-1999, and their families (children with or without partners) were randomly assigned to 10 sessions of a family therapy over a 3-5-month period, or to a waitlist control group. Both mothers and children completed assessments prior to and after the intervention phase. Children's blood samples collected at these two time points were used to measure cortisol and epigenome-wide DNA methylation patterns (Illumina EPIC array). Cortisol levels, and genome-wide DNA methylation changes pre-/postintervention were compared between children in the intervention and the waitlist groups. DNA methylation age and accelerated biological aging were calculated. RESULTS: Sixty-two women-child dyads completed the study, 30 were assigned first to the intervention group, and 32 to the waitlist control group. In adjusted linear regression, the family intervention was associated with a significant decline in cortisol levels compared to the waitlist control (ß = -124.72, 95% confidence interval [CI]: -197.4 to -52.1, p = .001). Children in the intervention group, compared to the waitlist control group, showed >1% differential methylation degree at 5819 CpG (5'-C-phosphate-G-3') sites across the genome (p < .01), with the largest methylation difference being 21%. However, none of these differences reached genome-wide significant levels. There was no significant difference in DNA methylation aging between the two groups. CONCLUSION: We find evidence that a tailored family-based intervention reduced stress levels in the children (based on cortisol levels), and modified DNA methylation levels at a number of sites across the genome. This study provides some preliminary evidence to suggest the potential for tailored interventions to help break the intergenerational transmission of trauma, however, large studies powered to detect associations at genome-wide significant levels are needed.

TARGET based m6A methylation-related genes predict prognosis relapsed B-cell acute lymphoblastic leukemia.

PURPOSE: The current study aims to investigate the significance of N6-methyladenosine (m6A) methylationrelated genes in the clinical prognosis of childhood relapsed B-cell acute lymphoblastic leukemia (B-ALLL) patient. METHODS: Transcriptome data and corresponding clinical data on m6A methylation-related genes (including 20 genes) were obtained from the Therapeutically Applicable Research To Generate Effective Treatments (TARGET) database. RESULTS: The bone marrow (BM) samples of 134 newly diagnosed (naive) and 116 relapsed B-ALL from TARGET were enrolled in the current study. Three genes (FTO, HNRNPC, RBM15B) showed significant up-regulation in relapsed B-ALL compared with that in naive B-ALL.The three genes had a significantly worse survival (P < 0.05). The LASSO Cox regression model was used to select the most predictive genes as prognostic indicators, and YTHDC1 and FTO were identified as prognostic factors for relapsed B-ALL. Finally, the results of multivariate regression analysis showed that the risk score of m6A methylation-related genes was an independent prognostic factor in relapsed B-ALL (P < 0.05). CONCLUSION: We found that the expression levels of m6A methylation-related genes were different in naive and relapsed patients with B-ALL and correlated with survival and prognosis.This implies that m6A methylation-related genes may be promising prognostic indicators or therapeutic targets for relapsed B-ALL.

The association between cumulative exposure to PM2.5 and DNA methylation measured using methyl-capture sequencing among COPD patients.

BACKGROUND: Particulate matter with a diameter of < 2.5 µm (PM2.5) influences gene regulation via DNA methylation; however, its precise mechanism of action remains unclear. Thus, this study aimed to examine the connection between personal PM2.5 exposure and DNA methylation in CpG islands as well as explore the associated gene pathways. METHODS: A total of 95 male patients with chronic obstructive pulmonary disease (COPD) were enrolled in this study. PM2.5 concentrations were measured for 12 months, with individual exposure recorded for 24 h every 3 months. Mean indoor and estimated individual PM2.5 exposure levels were calculated for short-term (7 days), mid-term (35 days), and long-term (90 days). DNA methylation analysis was performed on the blood samples, which, after PCR amplification and hybridization, were finally sequenced using an Illumina NovaSeq 6000 system. Correlation between PM2.5 exposure and CpG methylation sites was confirmed via a mixed-effects model. Functional enrichment analysis was performed on unique CpG methylation sites associated with PM2.5 exposure to identify the relevant biological functions or pathways. RESULTS: The number of CpG sites showing differential methylation was 36, 381, and 182 for the short-, mid-, and long-term indoor models, respectively, and 3, 98, and 28 for the short-, mid-, and long-term estimated exposure models, respectively. The representative genes were TMTC2 (p = 1.63 × 10-3, R2 = 0.656), GLRX3 (p = 1.46 × 10-3, R2 = 0.623), DCAF15 (p = 2.43 × 10-4, R2 = 0.623), CNOT6L (p = 1.46 × 10-4, R2 = 0.609), BSN (p = 2.21 × 10-5, R2 = 0.606), and SENP6 (p = 1.59 × 10-4, R2 = 0.604). Functional enrichment analysis demonstrated that the related genes were mostly associated with pathways related to synaptic transmission in neurodegenerative diseases and cancer. CONCLUSION: A significant association was observed between PM2.5 exposure and DNA methylation upon short-term exposure, and the extent of DNA methylation was the highest upon mid-term exposure. Additionally, various pathways related to neurodegenerative diseases and cancer were associated with patients with COPD. GOV IDENTIFIER: NCT04878367.

Epitranscriptomics and epigenetics: two sides of the same coin?

Gene expression is an intricate biological process that bridges gap between the genotype and the phenotype. Canonical and hereditable epigenetic mechanisms, such as histone and DNA modifications, regulate the release of genetic information encoded in DNA without altering the underlying sequence. Many other non-canonical players, such as chromatin regulators and noncoding RNAs, are also involved in regulating gene expression. Recently, RNA modifications (epitranscriptomics) have been shown to hold enormous potential in shaping cellular transcriptomes. However, their co-transcriptional nature and uncertain heritability mean that they fall outside the current definition of epigenetics, sparking an ongoing debate in the field. Here we will discuss the relationship between canonical and non-canonical epigenetic mechanisms that govern gene expression and offer our perspective on whether (or not) epitranscriptomic modifications can be classified as epigenetic mechanisms.

Identification of candidate genes and chemicals associated with osteonecrosis of femoral head by multiomics studies and chemical-gene interaction analysis.

Objectives: In-depth understanding of osteonecrosis of femoral head (ONFH) has revealed that degeneration of the hip cartilage plays a crucial role in ONFH progression. However, the underlying molecular mechanisms and susceptibility to environmental factors in hip cartilage that contribute to ONFH progression remain elusive. Methods: We conducted a multiomics study and chemical-gene interaction analysis of hip cartilage in ONFH. The differentially expressed genes (DEGs) involved in ONFH progression were identified in paired hip cartilage samples from 36 patients by combining genome-wide DNA methylation profiling, gene expression profiling, and quantitative proteomics. Gene functional enrichment and pathway analyses were performed via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Functional links between proteins were discovered through protein-protein interaction (PPI) networks. The ONFH-associated chemicals were identified by integrating the DEGs with the chemical-gene interaction sets in the Comparative Toxicogenomics Database (CTD). Finally, the DEGs, including MMP13 and CHI3L1, were validated via quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC). Results: Twenty-two DEGs were identified across all three omics levels in ONFH cartilage, 16 of which were upregulated and six of which were downregulated. The collagen-containing extracellular matrix (ECM), ECM structural constituents, response to amino acids, the relaxin signaling pathway, and protein digestion and absorption were found to be primarily involved in cartilage degeneration in ONFH. Moreover, ten major ONFH-associated chemicals were identified, including, benzo(a)pyrene, valproic acid, and bisphenol A. Conclusion: Overall, our study identified several candidate genes, pathways, and chemicals associated with cartilage degeneration in ONFH, providing novel clues into the etiology and biological processes of ONFH progression.

DNA methylation variations of DNA damage response correlate survival and local immune status in melanomas.

AIM: We aimed to explore the impact of DNA methylation alterations on the DNA damage response (DDR) in melanoma prognosis and immunity. MATERIAL & METHODS: Different melanoma cohorts with molecular and clinical data were included. RESULTS: Hierarchical clustering utilizing different combinations of DDR-relevant CpGs yielded distinct melanoma subtypes, which were characteristic of different prognoses, transcriptional function profiles of DDR, and immunity and immunotherapy responses but were associated with similar tumor mutation burdens. We then constructed and validated a clinically applicable 4-CpG risk-score signature for predicting survival and immunotherapy response. CONCLUSION: Our study describes the close interrelationship among DNA methylation, DDR machinery, local tumor immune status, melanoma prognosis, and immunotherapy response.