Gene Promoter Methylation Research Articles

Increased MAGE-C Family Gene Expression Levels as a Biomarker of Colon Cancer Through the Demethylation Mechanism

Background/Objectives: Colon cancer (CC) in Saudi Arabia is associated with a high death rate and is commonly identified at a more progressive stage. Therefore, it is critical to identify and characterize potential novel cancer-specific biomarkers to enhance early CC diagnosis. The goal was to assess their potential use as cancer biomarkers for the early detection and improvement of CC treatment. Methods: MAGE-C1, MAGE-C2, and MAGE-C3 family gene expression levels were examined using RT-PCR and qRT-PCR assays in 26 adjacent normal colon (NC) and CC tissue samples from male and female Saudi patients. Using several cell lines and the qRT-PCR technique, epigenetic control was also investigated to determine whether reduced treatment with 5-aza-2′-deoxycytidine, which reduces DNA methyltransferase, can increase the expression of the MAGE-C gene. The expression levels, promoter methylation, and prognostic significance of MAGE-C1, MAGE-C2, and MAGE-C3 genes across various cancers were analyzed using The Cancer Genome Atlas (TCGA) data. Additionally, the prognostic significance of these genes was assessed through Kaplan–Meier survival analysis. Results: The RT-PCR results showed that MAGE-C1, MAGE-C2, and MAGE-C3 gene expressions were significantly higher in the CC and NC tissues. The MAGE-C1 expression level was the highest in CC tissues (p < 0.0001), followed by MAGE-C3 (p = 0.0004) and MAGE-C2 (p = 0.0020) in descending order. The 5-aza-2′-deoxycytidine treatment significantly increased the mRNA expression levels of the MAGE-C1, MAGE-C2, and MAGE-C3 genes in HCT116, Caco-2, MCF-7, and MCF-10A cells. Expression analyses of TCGA samples revealed significant upregulation of these genes in several cancer types, with notable differences between normal, tumor, and metastatic tissues. Promoter methylation indicates hypomethylation in cancerous tissues. Survival analyses show that high expression levels of MAGE-C1 correlate with better prognosis, while MAGE-C3 is associated with poorer outcomes. Conclusions: These results demonstrate that MAGE-C genes are viable prospective biomarkers of CC controlled by hypomethylating drugs, consequently offering a possible treatment target for CC in a specific population.

Prognosis prediction via histological evaluation of cellular heterogeneity in glioblastoma

Glioblastomas (GBMs) are the most aggressive types of central nervous system tumors. Although certain genomic alterations have been identified as prognostic biomarkers of GBMs, the histomorphological features that predict their prognosis remain elusive. In this study, following an integrative diagnosis of 227 GBMs based on the 2021 World Health Organization classification system, the cases were histologically fractionated by cellular variations and abundance to evaluate the relationship between cellular heterogeneity and prognosis in combination with O-6-methylguanine-DNA methyltransferase gene promoter methylation (mMGMTp) status. GBMs comprised four major cell types: astrocytic, pleomorphic, gemistocytic, and rhabdoid cells. t-distributed stochastic neighbor embedding analysis using the histological abundance of heterogeneous cell types identified two distinct groups with significantly different prognoses. In individual cell component analysis, the abundance of gemistocytes showed a significantly favorable prognosis but confounding to mMGMTp status. Conversely, the abundance of epithelioid cells was correlated with the unfavorable prognosis. Linear model analysis showed the favorable prognostic utility of quantifying gemistocytic and epithelioid cells, independent of mMGMTp. The evaluation of GBM cell histomorphological heterogeneity is more effective for prognosis prediction in combination with mMGMTp analysis, indicating that histomorphological analysis is a practical and useful prognostication tool in an integrative diagnosis of GBMs.

Adenomatous Polyposis Coli (APC) Promoter Gene Methylation in Urine-Derived DNA: A Non-invasive Biomarker for Early Bladder Cancer Detection and Tumor Aggressiveness

Adenomatous Polyposis Coli (APC) Promoter Gene Methylation in Urine-Derived DNA: A Non-invasive Biomarker for Early Bladder Cancer Detection and Tumor Aggressiveness

Cohesin RAD21 Gene Promoter Methylation in Patients with Acute Myeloid Leukemia.

Aberrant gene promoter methylation is one of the hallmarks of Acute Myeloid Leukemia (AML). RAD21 is an important gene, implicated in sister chromatids cohesion, DNA repair, the regulation of gene transcription, apoptosis and hematopoiesis. In this study, we investigate the possible implication of RAD21 promoter methylation in AML pathogenesis using a cohort of AML patients and a cohort of healthy individuals. RAD21 promoter methylation was found in 24% of patients and in none of the controls (p = 0.023), indicating a possible contribution to AML development. Interestingly, a statistically higher frequency of RAD21 methylation was observed in patients with trisomy 8 (9/21, 42.9%, p = 0.021), while none of the patients with aberrations of chromosome 11 had RAD21 gene promoter methylation (0%, 0/11, p = 0.048). Patients with monosomal and complex karyotypes showed low frequencies of RAD21 methylation (7.7% and 15.4%, respectively) without reaching statistical significance. Moreover, ASXL1 mutations were not found to be associated with RAD21 methylation. This is the first study which provides evidence for a possible pathogenetic role of RAD21 promoter methylation in AML development and especially in AML with trisomy 8. Further studies of RAD21 promoter methylation in large series of different AML genetic subgroups may contribute to the elucidation of AML pathogenesis and to the identification of new epigenetic biomarkers with diagnostic and prognostic value.

Heterogeneous Transcriptional Landscapes in Human Sporadic Parathyroid Gland Tumors

The expression of several key molecules is altered in parathyroid tumors due to gene mutations, the loss of heterozygosity, and aberrant gene promoter methylation. A set of genes involved in parathyroid tumorigenesis has been investigated in sporadic parathyroid adenomas (PAds). Thirty-two fresh PAd tissue samples surgically removed from patients with primary hyperparathyroidism (PHPT) were collected and profiled for gene, microRNA, and lncRNA expression (n = 27). Based on a gene set including MEN1, CDC73, GCM2, CASR, VDR, CCND1, and CDKN1B, the transcriptomic profiles were analyzed using a cluster analysis. The expression levels of CDC73 and CDKN1B were the main drivers for clusterization. The samples were separated into two main clusters, C1 and C2, with the latter including two subgroups of five PAds (C2A) and nineteen PAds (C2B), both differing from C1 in terms of their lower expression of CDC73 and CDKN1B. The C2A PAd profile was also associated with the loss of TP73, an increased expression of HAR1B, HOXA-AS2, and HOXA-AS3 lncRNAs, and a trend towards more severe PHPT compared to C1 and C2B PAds. C2B PAds were characterized by a general downregulated gene expression. Moreover, CCND1 levels were also reduced as well as the expression of the lncRNAs NEAT1 and VLDLR-AS1. Of note, the deregulated lncRNAs are predicted to interact with the histones H3K4 and H3K27. Patients harboring C2B PAds had lower ionized and total serum calcium levels, lower PTH levels, and smaller tumor sizes than patients harboring C2A PAds. In conclusion, PAds display heterogeneous transcriptomic profiles which may contribute to the modulation of clinical and biochemical features. The general downregulated gene expression, characterizing a subgroup of PAds, suggests the tumor cells behave as quiescent resting cells, while the severity of PHPT may be associated with the loss of p73 and the lncRNA-mediated deregulation of histones.

Analysis of gliomas DNA methylation: Assessment of pre-analytical variables.

Precision oncology is driven by biomarkers. For glioblastoma multiforme (GBM), the most common malignant adult primary brain tumor, O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation is an important prognostic and treatment clinical biomarker. Time consuming pre-analytical steps such as biospecimen storage, fixation, sampling, and processing are sources of data irreproducibility, and all these pre-analytical variables are confounded by intratumor heterogeneity of MGMT promoter methylation. To assess the effect of pre-analytical variables on GBM DNA methylation, tissue storage/sampling (CryoGrid), sample preparation multi-sonicator (PIXUL), and 5-methylcytosine (5mC) DNA immunoprecipitation (Matrix MeDIP-qPCR/seq) platforms were used. MGMT promoter methylation status assayed by MeDIP-qPCR was validated with methylation specific PCR (MS-PCR). MGMT promoter methylation levels in frozen and formalin fixed paraffin embedded (FFPE) sample pairs were not statistically different, confirming reliability of FFPEs for MGMT promoter methylation analysis. Warm ex-vivo ischemia (up to 4hrs at 37oC) and 3 cycles of repeated sample thawing and freezing did not statistically impact 5mC at MGMT promoter, exon, and enhancer regions, indicating the resistance of DNA methylation to common variations in sample processing conditions that might be encountered in research and clinical settings. 26-34% of specimens exhibited intratumor heterogeneity in the MGMT DNA promoter methylation. These data demonstrate that variations in sample fixation, ischemia duration and temperature, and DNA methylation assay technique do not have a statistically significant impact on MGMT promoter methylation assessment. However, intratumor methylation heterogeneity underscores the value of multiple biopsies at different GBM geographic tumor sites in the evaluation of MGMT promoter methylation status. Matrix-MeDIP-seq analysis revealed that MGMT promoter methylation status clustered with other differentially methylated genomic loci (e.g. HOXA and lncRNAs) that are resilient to variation in the above pre-analytical conditions. These observations offer new opportunities to develop more granular data-based epigenetic GBM biomarkers. In this regard, the high throughput CryoGrid-PIXUL-Matrix toolbox could be useful.

The molecular significance of BRCA1 promoter methylation in peripheral blood cells in women with breast cancer in West Algeria

IntroductionEpigenetic alterations, in particular DNA methylation, are the most important mechanism that silences tumor suppressor genes during carcinogenesis. Methylation of the BRCA1 promoter in peripheral blood is associated with an increased risk of breast cancer. In the present study, we aimed, for the first time in western Algeria, to investigate the role of BRCA1 CpG promoter methylation in peripheral blood cells (PBCs) among breast cancer patients, as a potential biomarker for detecting breast cancer risk at an early age.Material and methodsThe methylation profile of the BRCA1 gene promoter and its frequency in PBCs, derived from 39 breast cancer patients, was explored by methylation-specific PCR (MSPCR). The association between methylation profiles and clinicopathological features was evaluated with SPSS statistics software to estimate a convenient biomarker for early detection of breast cancer.ResultsMSPCR results demonstrated that the methylation frequency of the BRCA1 gene promoter detected in PBCs is significantly higher than in other populations. It was observed in 23 of 39 (58.97%) breast cancer patients.ConclusionsOur study showed that the methylation of the BRCA1 gene promoter detected in PBCs’ DNA could have potential utility in clinical diagnostics as a new biomarker for breast cancer risk in Algerian women and for early detection.

The NRF2-KEAP1 pathway and epigenetic control in colorectal cancer: A promising prognostic and predictive biomarker

In colorectal cancer (CRC), important genes in the NRF2/KEAP1 pathway may undergo methylation, yet the exact genes that control this pathway in CRC are not entirely understood. Targeting the NRF2/KEAP1 pathway could be a valuable therapeutic strategy for colorectal cancer. Our research examined the methylation and expression of the KEAP1 gene in precancerous lesions and colorectal cancer, as well as investigated this pathway in the HT-29 cell line for potential CRC treatment. In this study, 208 frozen colorectal tissue samples were analysed, including 34 tumours, 60 precancerous lesions with adjacent normal tissues, and 20 normal tissue samples. The methylation-specific PCR and quantitative PCR were used to examine KEAP1 gene promoter methylation, and NRF2 and KEAP1 gene expressions, respectively. Furthermore, the HT 29 cell line was treated with 5-Azacytidine, followed by quantitative real-time PCR to evaluate post-demethylation KEAP1 and NRF2 mRNA expression. Unlike NRF2, our research revealed a notable reduction in KEAP1 gene expression in CRC tissues compared to adjacent normal tissues (p=0.02). Intriguingly, treating the HT-29 cell line with 5-Azacytidine led to a significant increase in KEAP1 gene expression compared to untreated cells (P=0.03), with no significant alteration observed in NRF2 gene expression. Examination of CpG islands within the KEAP1 gene promoter indicated extensive hypermethylation in 58.8% of tumour tissues compared to adjacent normal samples. These findings indicate that decreased KEAP1 gene expression resulting from promoter hypermethylation could interfere with the NRF2/KEAP1 pathway, a crucial mechanism in colorectal carcinogenesis. The study proposes that KEAP1 may play a significant role in the progression of CRC and could potentially serve as a biomarker for diagnosing and monitoring therapy in CRC

Evaluation of ABCB1 Gene Promoter Methylation in Patients with Ulcerative Colitis

Background: The pathogenesis of inflammatory bowel disease may be associated with the disruption in interactions between the immune system and gut flora. Epigenetic mechanisms especially, DNA methylation appear to be significant regarding the interaction between the environment and genome. ABCB1 is the encoding gene for multi-drug resistance protein 1 (MDR1) (P-glycoprotein), which is an important transmembrane protein responsible for the efflux of cellular molecules from the intestinal wall to the lumen Method: In this study, we compared the methylation status of the promoter of ABCB1 in rectal mucosa of patients with ulcerative colitis (UC) and healthy controls by using the bisulfite conversion system and realtime quantitative multiplex methylation-specific PCR (QM-MSP). Results: We demonstrated that the mucosal specimen of 26 UC patients had significantly higher levels of promoter methylation in comparison to 26 controls. Conclusion: As the first investigation of Iranian patients with UC, we showed that patients had higher levels of ABCB1 promoter methylation in their inflammatory rectal mucosa compared to controls. However, this altered state of methylation did not associate with the characteristics of the patients such as age and sex. Our findings are a basis for further studies on concurrent assessment of promoter methylation and expression of ABCB1 in UC.

Apoptotic effect of melatonin on ER-positive breast cancer cell lines: ADGRL4 gene expression and promoter methylation.

Breast cancer (BC) is the second most common malignancy worldwide. ADGRL4, as a modulator of angiogenesis, undergoes various epigenetic modifications affecting its biological functions. In this study, we aimed to assess ADGRL4 promoter methylation status and its expression levels in primary breast tumors and to evaluate its potency as a plausible prognostic biomarker in BC. Furthermore, we evaluated the effect of melatonin on ADGRL4 expression and viability of BC cells in vitro. One hundred breast tumor tissue samples and adjacent non-tumor tissues were collected, followed by DNA isolation, bisulfite conversion, qRT-PCR, qMSP assay, and immunoblotting. In addition, four BC cell lines were treated with melatonin and subjected to ADGRL4 expression analysis and apoptosis assay. We found a significant correlation between ADGRL4 expression levels and HER2 status and stage of disease (P < 0.05). We observed a substantial attenuation in ADGRL4 promoter methylation in tumor samples compared to marginal non-tumor samples. A significantly lower expression of ADGRL4 was detected in two BC cell lines in the presence of melatonin. MCF-7 and BT474 melatonin-treated cell lines showed a significantly higher number of apoptotic cells than non-treated cells (P < 0.0001). Based on the receiver operating characteristic (ROC) curve analysis, ADGRL4 expression and ADGRL4 promoter methylation status showed moderate prognostic value. We found that melatonin has anti-cancer effects on BC cells. In addition, ADGRL4 expression can potentially be used as a prognostic biomarker in BC.

Diagnostic efficacy of SEPT9 and PAX5 gene methylation in gastrointestinal cancer and precancerous lesions.

To assess the diagnostic efficacy of SEPT9 along with PAX5 gene methylation detection in gastrointestinal cancer and precancerous lesions, the peripheral blood of 62 patients with gastric cancer (GC) and 60 patients with no evidence of disease (as the control group) were retrospectively collected. The methylation rates of PAX5 and SEPT9 gene promoters in blood samples of GC group were detected by PCR. At the same time, the differences in methylation rates of genes in the two groups were compared, and the predictive value of plasma methylation PAX5 and SEPT9 in GC was evaluated by receiver operating characteristic (ROC) curve. We found that there were 41 cases of methylated PAX5 gene promoter region and 39 cases of methylated SEPT9 gene promoter region in GC group. The control group contained 14 cases of PAX5 gene promoter methylation and 12 cases of RNF¹80 gene promoter methylation. The occurrence of PAX5 promoter methylation was correlated with age of GC patients. There were statistically significant differences in mSEPT9 gene in patients with different TNM stages. Kaplan-Meier survival curve analysis revealed that the three-year overall survival rate of GC patients with PAX5 methylation was lower than that of GC patients without PAX5 methylation. No significant difference was discovered in 3-year overall survival rate between GC patients with SEPT9 methylation and those without SEPT9 methylation. Combined detection could not improve the diagnostic value of GC, but could promote diagnosis sensitivity. In summary, the risk of PAX5 and SEPT9 gene methylation in GC patients presents higher when compared with healthy people. PAX5 gene methylation is closely related to age, while SEPT9 is closely related to tumor TNM stage, and PAX5 gene methylation can decrease the survival rate of GC patients. Detection of PAX5 gene methylation level can assist in evaluating the prognosis of GC patients.

DiPRO1 distinctly reprograms muscle and mesenchymal cancer cells

We have recently identified the uncharacterized ZNF555 protein as a component of a productive complex involved in the morbid function of the 4qA locus in facioscapulohumeral dystrophy. Subsequently named DiPRO1 (Death, Differentiation, and PROliferation related PROtein 1), our study provides substantial evidence of its role in the differentiation and proliferation of human myoblasts. DiPRO1 operates through the regulatory binding regions of SIX1, a master regulator of myogenesis. Its relevance extends to mesenchymal tumors, such as rhabdomyosarcoma (RMS) and Ewing sarcoma, where DiPRO1 acts as a repressor via the epigenetic regulators TIF1B and UHRF1, maintaining methylation of cis-regulatory elements and gene promoters. Loss of DiPRO1 mimics the host defense response to virus, awakening retrotransposable repeats and the ZNF/KZFP gene family. This enables the eradication of cancer cells, reprogramming the cellular decision balance towards inflammation and/or apoptosis by controlling TNF-α via NF-kappaB signaling. Finally, our results highlight the vulnerability of mesenchymal cancer tumors to si/shDiPRO1-based nanomedicines, positioning DiPRO1 as a potential therapeutic target.

Optimizing examination of methylenetetrahydrofolate reductase gene promoter methylation in cleft lip with or without cleft palate non-syndromic patients using the pyrosequencing method

Optimizing examination of methylenetetrahydrofolate reductase gene promoter methylation in cleft lip with or without cleft palate non-syndromic patients using the pyrosequencing method

A pan-cancer analysis unveiling the function of NR4A family genes in tumor immune microenvironment, prognosis, and drug response.

NR4A family genes play crucial roles in cancers. However, the role of NR4A family genes in cancers remains paradoxical as they promote or suppress tumorigenesis. We aimed to conduct comprehensive analyses of the association between the expression of NR4A family genes and tumor microenvironment (TME) based on bioinformatics methods. We collected RNA-seq data from 33 cancer types and 20 normal tissue sites from the TCGA and GTEx databases. Expression patterns of NR4A family genes and their associations with DNA methylation, miRNA, overall survival, drug responses, and tumor microenvironment were investigated. Significant downregulation of all NR4A family genes was observed in 15 cancer types. DNA promoter methylation and expression of NR4A family genes were negatively correlated in five cancers. The expression of 10 miRNAs targeting NR4A family genes was negatively correlated with the expression of NR4A family genes. High expression of all NR4A family genes was associated with poor prognosis in stomach adenocarcinoma and increased expressions of NR4A2 and NR4A3 were associated with poor prognosis in adrenocortical carcinoma. In addition, we found an elevated expression of NR4A2, which enhances the response to various chemotherapeutic drugs, whereas NR4A3 decreases drug sensitivity. Interestingly, in breast cancer, NR4A3 was significantly associated with C2 (IFN-γ dominant), C3 (inflammatory), and C6 (TGF-β dominant) immune subtypes and infiltrated immune cell types, implying both oncogenic and tumor-suppressive functions of NR4A3 in breast cancer. The NR4A family genes have the potential to serve as a diagnostic, prognostic, and immunological marker of human cancers.

A systematic review on the contribution of DNA methylation to hearing loss

BackgroundDNA methylation may have a regulatory role in monogenic sensorineural hearing loss and complex, polygenic phenotypic forms of hearing loss, including age-related hearing impairment or Meniere disease. The purpose of this systematic review is to critically assess the evidence supporting a functional role of DNA methylation in phenotypes associated with hearing loss.ResultsThe search strategy yielded a total of 661 articles. After quality assessment, 25 records were selected (12 human DNA methylation studies, 5 experimental animal studies and 8 studies reporting mutations in the DNMT1 gene). Although some methylation studies reported significant differences in CpG methylation in diverse gene promoters associated with complex hearing loss phenotypes (ARHI, otosclerosis, MD), only one study included a replication cohort that supported a regulatory role for CpG methylation in the genes TCF25 and POLE in ARHI. Conversely, several studies have independently confirmed pathogenic mutations within exon 21 of the DNMT1 gene, which encodes the DNA (cytosine-5)-methyltransferase 1 enzyme. This methylation enzyme is strongly associated with a rare disease defined by autosomal dominant cerebellar ataxia, deafness and narcolepsy (ADCA-DN). Of note, rare variants in DNMT1 and DNMT3A genes have also been reported in noise-induced hearing loss.ConclusionsEvidence supporting a functional role for DNA methylation in hearing loss is limited to few genes in complex disorders such as ARHI. Mutations in the DNMT1 gene are associated with ADCA-DN, suggesting the CpG methylation in hearing loss genes deserves further attention in hearing research.

Epigenetic regulation of DNA repair gene program by Hippo/YAP1-TET1 axis mediates sorafenib resistance in HCC

Hepatocellular carcinoma (HCC) is a malignancy that occurs worldwide and is generally associated with poor prognosis. The development of resistance to targeted therapies such as sorafenib is a major challenge in clinical cancer treatment. In the present study, Ten-eleven translocation protein 1 (TET1) was found to be highly expressed in sorafenib-resistant HCC cells and knockdown of TET1 can substantially improve the therapeutic effect of sorafenib on HCC, indicating the potential important roles of TET1 in sorafenib resistance in HCC. Mechanistic studies determined that TET1 and Yes-associated protein 1 (YAP1) synergistically regulate the promoter methylation and gene expression of DNA repair-related genes in sorafenib-resistant HCC cells. RNA sequencing indicated the activation of DNA damage repair signaling was extensively suppressed by the TET1 inhibitor Bobcat339. We also identified TET1 as a direct transcriptional target of YAP1 by promoter analysis and chromatin-immunoprecipitation assays in sorafenib-resistant HCC cells. Furthermore, we showed that Bobcat339 can overcome sorafenib resistance and synergized with sorafenib to induce tumor eradication in HCC cells and mouse models. Finally, immunostaining showed a positive correlation between TET1 and YAP1 in clinical samples. Our findings have identified a previously unrecognized molecular pathway underlying HCC sorafenib resistance, thus revealing a promising strategy for cancer therapy.Graphical

Computational Predictions of MGMT Promoter Methylation in Gliomas: A Mathematical Radiogenomics Approach

In the treatment of glioblastomas, non-invasive methods for determining MGMT gene promoter methylation status are crucial due to their implications for chemotherapy responsiveness. This study utilizes a mathematical and computational framework to extract and analyze radiogenomic data from MRI images to predict the methylation status. The first step in our framework involves extracting radiogenomic data from MRI images. This process requires sophisticated image processing techniques to convert MRI scans into a format suitable for machine learning analysis. The features extracted include textural patterns, intensity distributions, and other relevant radiomic characteristics.To identify the most significant features, we employ a Random Forest (RF) algorithm. Mathematically, RF is an ensemble learning method that operates by constructing multiple decision trees during training and outputting the mode of the classes for classification tasks. The importance of each feature is evaluated based on its contribution to the accuracy of the model, quantified by metrics such as Gini impurity or information gain. Employing advanced machine learning models like VGG19, ResNet50, and Sequential FCNet Artificial Neural Networks, alongside traditional classifiers such as Naive Bayes and Logistic Regression, we analyze features identified by a Random Forest algorithm. Our mathematical approach ensures rigorous evaluation of model accuracy through sensitivity, specificity, and other performance metrics, presenting the Sequential FCNet ANN combined with ResNet50 as the superior model. This research contributes to the field of precision healthcare by enhancing the mathematical methods used in the non-invasive diagnosis of glioblastomas.

No benefit from TMZ treatment in glioblastoma with truly unmethylated MGMT promoter: Reanalysis of the CE.6 and the pooled Nordic/NOA-08 trials in elderly glioblastoma patients.

The treatment of elderly/ frail patients with glioblastoma is a balance between avoiding undue toxicity, while not withholding effective treatment. It remains debated, whether these patients should receive combined chemo-radiotherapy with temozolomide (RT/TMZ→TMZ) regardless of the O6-methylguanine DNA methyltransferase gene promoter (MGMTp) methylation status. MGMT is a well-known resistance factor blunting the treatment effect of TMZ, by repairing the most genotoxic lesion. Epigenetic silencing of the MGMTp sensitizes glioblastoma to TMZ. For risk-adapted treatment, it is of utmost importance to accurately identify patients, who will not benefit from TMZ treatment. Here, we present a reanalysis of the clinical trials CE.6 and the pooled NOA-08 and Nordic trials in elderly glioblastoma patients that compared RT to RT/TMZ→TMZ, or RT to TMZ, respectively. For 687 patients with available MGMTp methylation data, we applied a cutoff discerning truly unmethylated glioblastoma, established in a pooled analysis of 4 clinical trials for glioblastoma, with RT/TMZ→TMZ treatment, using the same quantitative methylation-specific MGMTp PCR assay. When applying this restricted cutoff to the elderly patient population, we confirmed that glioblastoma with truly unmethylated MGMTp derived no benefit from TMZ treatment. In the Nordic/NOA-08 trials, RT was better than TMZ, suggesting little or no benefit from TMZ. For evidence-based treatment of glioblastoma patients validated MGMTp methylation assays should be used that accurately identify truly unmethylated patients. Respective stratified management of patients will reduce toxicity without compromising outcomes and allow testing of more promising treatment options.

Mecp2 promotes the anti-inflammatory effect of alpinetin via epigenetic modification crosstalk.

In recent years, inflammatory disorders have emerged as a significant concern for human health. Through ongoing research on anti-inflammatory agents, alpinetin has shown promising anti-inflammatory properties, including involvement in epigenetic modification pathways. As a crucial regulator of epigenetic modifications, Mecp2 may play a role in modulating the epigenetic effects of alpinetin, potentially impacting its anti-inflammatory properties. To test this hypothesis, two key components, p65 (a member of NF-KB family) and p300 (a type of co-activator), were screened by the expression profiling microarray, which exhibited a strong correlation with the intensity of LPS stimulation in mouse macrophages. Meanwhile, alpinetin demonstrates the anti-inflammatory properties through its ability to disrupt the synthesis of p65 and its interaction with promoters of inflammatory genes, yet it did not exhibit similar effects on p300. Additionally, Mecp2 can inhibit the binding of p300 by attaching to the methylated inflammatory gene promoter induced by alpinetin, leading to obstacles in promoter acetylation and subsequently impacting the binding of p65, ultimately enhancing the anti-inflammatory capabilities of alpinetin. Similarly, in a sepsis mouse model, it was observed that homozygotes overexpressing Mecp2 showed a greater reduction in organ damage and improved survival rates compared to heterozygotes when administered by alpinetin. However, blocking the expression of DNA methyltransferase 3A (DNMT3A) resulted in the loss of Mecp2's anti-inflammatory assistance. In conclusion, Mecp2 may augment the anti-inflammatory effects of alpinetin through epigenetic 'crosstalk', highlighting the potential efficacy of a combined therapeutic strategy involving Mecp2 and alpinetin for anti-inflammatory intervention.

Molecular genomic and epigenomic characteristics related to aspirin and clopidogrel resistance

BackgroundMediators, genomic and epigenomic characteristics involving in metabolism of arachidonic acid by cyclooxygenase (COX) and lipoxygenase (ALOX) and hepatic activation of clopidogrel have been individually suggested as factors associated with resistance against aspirin and clopidogrel. The present multi-center prospective cohort study evaluated whether the mediators, genomic and epigenomic characteristics participating in arachidonic acid metabolism and clopidogrel activation could be factors that improve the prediction of the aspirin and clopidogrel resistance in addition to cardiovascular risks.MethodsWe enrolled 988 patients with transient ischemic attack and ischemic stroke who were evaluated for a recurrence of ischemic stroke to confirm clinical resistance, and measured aspirin (ARU) and P2Y12 reaction units (PRU) using VerifyNow to assess laboratory resistance 12 weeks after aspirin and clopidogrel administration. We investigated whether mediators, genotypes, and promoter methylation of genes involved in COX and ALOX metabolisms and clopidogrel activation could synergistically improve the prediction of ischemic stroke recurrence and the ARU and PRU levels by integrating to the established cardiovascular risk factors.ResultsThe logistic model to predict the recurrence used thromboxane A synthase 1 (TXAS1, rs41708) A/A genotype and ALOX12 promoter methylation as independent variables, and, improved sensitivity of recurrence prediction from 3.4% before to 13.8% after adding the mediators, genomic and epigenomic variables to the cardiovascular risks. The linear model we used to predict the ARU level included leukotriene B4, COX2 (rs20417) C/G and thromboxane A2 receptor (rs1131882) A/A genotypes with the addition of COX1 and ALOX15 promoter methylations as variables. The linear PRU prediction model included G/A and prostaglandin I receptor (rs4987262) G/A genotypes, COX2 and TXAS1 promoter methylation, as well as cytochrome P450 2C19*2 (rs4244285) A/A, G/A, and *3 (rs4986893) A/A genotypes as variables. The linear models for predicting ARU (r = 0.291, R2 = 0.033, p < 0.01) and PRU (r = 0.503, R2 = 0.210, p < 0.001) levels had improved prediction performance after adding the genomic and epigenomic variables to the cardiovascular risks.ConclusionsThis study demonstrates that different mediators, genomic and epigenomic characteristics of arachidonic acid metabolism and clopidogrel activation synergistically improved the prediction of the aspirin and clopidogrel resistance together with the cardiovascular risk factors.Trial registrationURL: https://www.clinicaltrials.gov; Unique identifier: NCT03823274.