scholarly journals EGFR DNA Methylation Correlates With EGFR Expression, Immune Cell Infiltration, and Overall Survival in Lung Adenocarcinoma

2021 ◽  
Vol 11 ◽  
Author(s):  
Zhanyu Xu ◽  
Fanglu Qin ◽  
Liqiang Yuan ◽  
Jiangbo Wei ◽  
Yu Sun ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Protein Expression ◽  
Lung Adenocarcinoma ◽  
Methylation Level ◽  
Promoter Region ◽  
Body Region ◽  
Gene Body ◽  
Immune Infiltration ◽  
Cpg Sites ◽  
Gene Body Region

BackgroundThe epidermal growth factor receptor (EGFR) is a primary target of molecular targeted therapy for lung adenocarcinoma (LUAD). The mechanisms that lead to epigenetic abnormalities of EGFR in LUAD are still unclear. The purpose of our study was to evaluate the abnormal methylation of EGFR CpG sites as potential biomarkers for LUAD.MethodsTo assess the differentially methylation CpG sites of EGFR in LUAD, we used an integrative study of Illumina HumanMethylation450K and RNA-seq data from The Cancer Genome Atlas (TCGA). We evaluated and compared EGFR multiple-omics data to explore the role of CpG sites located in EGFR promoter regions and gene body regions and the association with transcripts, protein expression levels, mutations, and somatic copy number variation. We calculated the correlation coefficients between CpG sites of EGFR and immune infiltration fraction (by MCPcounter and ESTIMATE) and immune-related pathways in LUAD. Finally, we validated the differential methylation of clinically and prognostically relevant CpG sites using quantitative methylation-specific PCR (qMSP).ResultsWe found that the methylation level of many EGFR CpGs in the promoter region was negatively correlated with the transcription level, protein expression, and SCNV, while the methylation at the gene body region was positively correlated with these features. The methylation level of EGFR CpGs in the promoter region was positively correlated with the level of immune infiltration and IFN-γ signature, while the opposite was found for methylation of the gene body region. The qMSP results showed that cg02316066 had a high methylation level, while cg02166842 had a low methylation level in LUAD. There was a high degree of co-methylation between cg02316066 and cg03046247.ConclusionOur data indicate that EGFR is an epigenetic regulator in LUAD acting through DNA methylation. Our research provides a theoretical basis for the further detection of EGFR DNA methylation as a predictive biomarker for LUAD survival and immunotherapy.

scholarly journals Association of Aberrant DNA Methylation Level in the CD4 and JAK-STAT-Pathway-Related Genes with Mastitis Indicator Traits in Chinese Holstein Dairy Cattle

Animals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 65
Author(s):  
Tahir Usman ◽  
Nawab Ali ◽  
Yachun Wang ◽  
Ying Yu
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Dairy Cattle ◽  
Methylation Level ◽  
Promoter Region ◽  
Promoter Regions ◽  
Cpg Sites ◽  
Cell Counts ◽  
Aberrant Dna Methylation ◽  
Stat Pathway

The present study was designed to evaluate the gene expression and DNA methylation level in the promoter region of the CD4 and the JAK-STAT-pathway-related genes. A total of 24 samples were deployed in the gene expression and 118 samples were used in the DNA methylation study. Student’s t-tests were used to analyze the gene expression and DNA methylation. The evaluation of DNA methylation in promoter regions of JAK2 and STAT5A revealed hypo-methylation levels of CpG sites and higher gene expression in cows diagnosed with mastitis as compared to the healthy control, and vice versa in those with CD4. DNA methylation was negatively correlated with gene expression in JAK2, STAT5A, and CD4 genes. Six, two, and four active transcription factors were identified on the CpG sites in the promoter regions of JAK2, STAT5A, and CD4 genes, respectively. Regarding correlation analysis, the DNA methylation levels of CD4 showed significantly higher positive correlations with somatic cell counts (p < 0.05). Findings of the current study inferred that aberrant DNA methylation in the CpG sites at the 1 kb promoter region in JAK2, STAT5A, and CD4 genes due to mastitis in cows can be used as potential epigenetic markers to estimate bovine mastitis susceptibility in dairy cattle.

scholarly journals Correlation Patterns Between DNA Methylation and Gene Expression in The Cancer Genome Atlas

2019 ◽  
Vol 18 ◽  
pp. 117693511982877 ◽  
Author(s):  
John CG Spainhour ◽  
Hong Seo Lim ◽  
Soojin V Yi ◽  
Peng Qiu
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Promoter Region ◽  
The Cancer Genome Atlas ◽  
Gene Body ◽  
Cpg Sites ◽  
Cpg Site ◽  
Cancer Genome Atlas ◽  
Genome Atlas

Background: DNA methylation is a form of epigenetic modification that has been shown to play a significant role in gene regulation. In cancer, DNA methylation plays an important role by regulating the expression of oncogenes. The role of DNA methylation in the onset and progression of various cancer types is now being elucidated as more large-scale data become available. The Cancer Genome Atlas (TCGA) provides a wealth of information for the analysis of various molecular aspects of cancer genetics. Gene expression data and DNA methylation data from TCGA have been used for a variety of studies. A traditional understanding of the effects of DNA methylation on gene expression has linked methylation of CpG sites in the gene promoter region with the decrease in gene expression. Recent studies have begun to expand this traditional role of DNA methylation. Results: Here we present a pan-cancer analysis of correlation patterns between CpG methylation and gene expression. Using matching patient data from TCGA, 33 cancer-specific correlations were calculated for each CpG site and the expression level of its corresponding gene. These correlations were used to identify patterns on a per-site basis as well as patterns of methylation across the gene body. Using these identified patterns, we found genes that contain conflicting methylation signals beyond the commonly accepted association between the promoter region methylation and silencing of gene expression. Beyond gene body methylation in whole, we examined individual CpG sites and show that, even in the same gene body, some sites can have a contradictory effect on gene expression in cancers. Conclusions: We observed that within promoter regions there was a substantial amount of positive correlation between methylation and gene expression, which contradicts the commonly accepted association. We observed that the correlation between CpG methylation and gene expression does not exhibit in a tissue-specific manner, suggesting that the effects of methylation on gene expression are largely tissue independent. The analysis of correlation associated with the location of the CpG site in the gene body has led to the identification of several different methylation patterns that affect gene expression, and several examples of methylation activating gene expression were observed. Distinctly opposing or conflicting effects were seen in close proximity on the gene body, where negative and positive correlations were seen at the neighboring CpG sites.

EPIGENETIC ALTERATIONS ASSOCIATED WITH PREMATURE OVARIAN FAILURE

2008 ◽  
Vol 31 (4) ◽  
pp. 11
Author(s):  
Manda Ghahremani ◽  
Courtney W Hannah ◽  
Maria Peneherrera ◽  
Karla L Bretherick ◽  
Margo R Fluker ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Premature Ovarian Failure ◽  
Promoter Region ◽  
Gene Promoter ◽  
Ovarian Failure ◽  
P Value ◽  
Epigenetic Alterations ◽  
Methylation Array ◽  
Cpg Sites ◽  
Deficient Mice

Background/Purpose: Premature ovarian failure (POF) affects 1% of women with a largely idiopathic and poorly understood etiology. The objective of this study was to identify specific epigenetic alterations by measuring DNA methylation of gene regulatory regions in women with POF vs. controls. Methods: Blood samples were collected from idiopathic POFpatients (Amenorrhea for at least 3 months and 2 serum FSH levels of > 40mIU/ml obtained > 1 month apart prior to age 40) and control women (CW) (healthy pregnancy after age 37 with out a pregnancy loss). Genomic DNA was extracted from EDTA anticoagulated blood and bisulfite converted for analysis using the Illumina Golden Gate Methylation Panel which measures DNA methylation at 1506 CpG sites in the promoter regions of 807 genes in 10 POF and 12 CW. Candidate genes with altered epigenetic marks between POF and CW at a nominal P-value < 0.05 were identified using a t-testcomparison within the Illumina bead studio software. Genes of interest were further analyzed for quantitative methylation at specific CpG sites using pyrosequencing in 30 POF and 30 CW. Results: Comparison of DNA methylation profiles of our initial POF and CW groups identified several genes with statistically significanthyper- or hypo- methylation in the POF group (P < 0.05), including the Androgen Receptor (AR)promoter region, which was significantly hypermethylated. To further validate these results, DNA methylation of the AR gene promoter was quantified bypryosequencing in a larger group of POF and CW. Pyrosequencing further confirmed a significantly higher DNA methylation of the AR promoter region inPOF vs. CW (P=0.007). Conclusions: This is a novel study identifying epigenetic alterations in POF. The hypermethylation of the AR gene in POF patients may cause decreased level of the AR in these women. This is especially interesting given a recent report of induced POF in AR deficient mice^1. Specific epigenetic markers, as identified by DNA methylation array profiling in blood, may serve as useful biomarkers for POF and other fertility disorders. However, it will need to be determined if these methylation changes are present prior to diagnosis, or are a consequence of menopause itself. Reference: 1.Hiroko S. et al. Premature ovarian failure in androgenreceptor deficient mice. PNAS;103:224-9

scholarly journals Association between DNA Methylation of the BDNF Promoter Region and Clinical Presentation in Alzheimer's Disease

2015 ◽  
Vol 5 (1) ◽  
pp. 64-73 ◽  
Author(s):  
Tomoyuki Nagata ◽  
Nobuyuki Kobayashi ◽  
Jumpei Ishii ◽  
Shunichiro Shinagawa ◽  
Ritsuko Nakayama ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Dna Methylation ◽  
Methylation Level ◽  
Clinical Presentation ◽  
Neuropsychological Test ◽  
Cpg Sites ◽  
The Brain ◽  
Normal Controls ◽  
Methylation Ratio

Background/Aims: In the present study, we examined whether DNA methylation of the brain-derived neurotrophic factor (BDNF) promoter is associated with the manifestation and clinical presentation of Alzheimer's disease (AD). Methods: Of 20 patients with AD and 20 age-matched normal controls (NCs), the DNA methylation of the BDNF promoter (measured using peripheral blood samples) was completely analyzed in 12 patients with AD and 6 NCs. The resulting methylation levels were compared statistically. Next, we investigated the correlation between the DNA methylation levels and the clinical presentation of AD. Results: The total methylation ratio (in %) of the 20 CpG sites was significantly higher in the AD patients (5.08 ± 5.52%) than in the NCs (2.09 ± 0.81%; p < 0.05). Of the 20 CpG sites, the methylation level at the CpG4 site was significantly higher in the AD subjects than in the NCs (p < 0.05). Moreover, the methylation level was significantly and negatively correlated with some neuropsychological test subscores (registration, recall, and prehension behavior scores; p < 0.05). Conclusion: These results suggest that the DNA methylation of the BDNF promoter may significantly influence the manifestation of AD and might be associated with its neurocognitive presentation.

scholarly journals Mining the Selective Remodeling of DNA Methylation in Promoter Regions to Identify Robust Gene-Level Associations With Phenotype

2021 ◽  
Vol 8 ◽  
Author(s):  
Yuan Quan ◽  
Fengji Liang ◽  
Si-Min Deng ◽  
Yuexing Zhu ◽  
Ying Chen ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Promoter Region ◽  
Biological Significance ◽  
Biological Efficiency ◽  
Body Region ◽  
Promoter Regions ◽  
Exposure Factor ◽  
Epigenetic Events ◽  
Gene Level ◽  
Disease Related Gene

Epigenetics is an essential biological frontier linking genetics to the environment, where DNA methylation is one of the most studied epigenetic events. In recent years, through the epigenome-wide association study (EWAS), researchers have identified thousands of phenotype-related methylation sites. However, the overlaps of identified phenotype-related DNA methylation sites between various studies are often quite small, and it might be due to the fact that methylation remodeling has a certain degree of randomness within the genome. Thus, the identification of robust gene-phenotype associations is crucial to interpreting pathogenesis. How to integrate the methylation values of different sites on the same gene and to mine the DNA methylation at the gene level remains a challenge. A recent study found that the DNA methylation difference of the gene body and promoter region has a strong correlation with gene expression. In this study, we proposed a Statistical difference of DNA Methylation between Promoter and Other Body Region (SIMPO) algorithm to extract DNA methylation values at the gene level. First, by choosing to smoke as an environmental exposure factor, our method led to significant improvements in gene overlaps (from 5 to 17%) between different datasets. In addition, the biological significance of phenotype-related genes identified by SIMPO algorithm is comparable to that of the traditional probe-based methods. Then, we selected two disease contents (e.g., insulin resistance and Parkinson’s disease) to show that the biological efficiency of disease-related gene identification increased from 15.43 to 44.44% (p-value = 1.20e–28). In summary, our results declare that mining the selective remodeling of DNA methylation in promoter regions can identify robust gene-level associations with phenotype, and the characteristic remodeling of a given gene’s promoter region can reflect the essence of disease.

scholarly journals DNA methylation patterns of β-globin cluster in β-thalassemia patients

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Xiuqin Bao ◽  
Yangjin Zuo ◽  
Diyu Chen ◽  
Cunyou Zhao
Keyword(s):  
Dna Methylation ◽  
Cord Blood ◽  
Methylation Level ◽  
Epigenetic Modification ◽  
Fetal Hemoglobin ◽  
Cpg Sites ◽  
Hbf Level ◽  
Globin Promoter ◽  
Methylation Patterns ◽  
Normal Controls

Abstract Background Reactivation of fetal hemoglobin (HbF, α2γ2) holds a therapeutic target for β-thalassemia and sickle cell disease. Although many HbF regulators have been identified, the methylation patterns in β-globin cluster driving the fetal-to-adult hemoglobin switch remains to be determined. Results Here, we evaluated DNA methylation patterns of the β-globin cluster from peripheral bloods of 105 β0/β0 thalassemia patients and 44 normal controls. We also recruited 15 bone marrows and 4 cord blood samples for further evaluation. We identified that the CpG sites in the locus control region (LCR) DNase I hypersensitive site 4 and 3 (HS4-3) regions, and γ- and β-globin promoters displayed hypomethylation in β0/β0-thalassemia patients, especially for the patients with high HbF level, as compared with normal controls. Furthermore, hypomethylations in most of CpG sites of the HS4-3 core regions were also observed in bone marrows (BM) of β0/β0-patients compared with normal controls; and methylation level of γ-globin promoter -50 and + 17 CpG sites showed lower methylation level in patients with high HbF level compared with those with low HbF level and a negative correlation with HbF level among β0-thalassemia patients. Finally, γ-globin promoter + 17 and + 50 CpG sites also displayed significant hypomethylation in cord blood (CB) tissues compared with BM tissues from normal controls. Conclusions Our findings revealed methylation patterns in β-globin cluster associated with β0 thalassemia disease and γ-globin expression, contributed to understand the epigenetic modification in β0 thalassemia patients and provided candidate targets for the therapies of β-hemoglobinopathies.

scholarly journals Hypermethylation of the TSPOAP1-AS1 Promoter May Be Associated with Obesity in Overweight/Obese Korean Subjects

2020 ◽  
Vol 21 (9) ◽  
pp. 3307
Author(s):  
Nam-Hui Yim ◽  
Min Ho Cha ◽  
Myung Sunny Kim
Keyword(s):  
Dna Methylation ◽  
Methylation Level ◽  
Promoter Region ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Amplicon Sequencing ◽  
Obese Group ◽  
Gene Encoding ◽  
Obese Subjects ◽  
Positive Correlations

Obesity is a major chronic disease associated with the risk of serious cardiovascular or endocrinal diseases, such as hypertension, diabetes, atherosclerosis and stroke. Considerable interest has been directed towards the potential effects of epigenetic variations in obesity. In this study, we evaluated DNA methylation level at the promoter region of the gene encoding TSPO-associated protein 1 antisense RNA 1 (TSPOAP1-AS1) in 80 overweight/obese subjects (body mass index (BMI) > 25) and 104 non-obese subjects who participated in the SOPI-Stroke study in Korea. DNA methylation was measured using bisulfite amplicon sequencing (BSAS). A general linear model or relative correlation was used to determine the effects of DNA methylation on obesity and obese phenotypes. Notably, the mean level of DNA methylation was significantly higher in the overweight/obese group than in the non-obese group (18.62% vs. 17.18%). Further analyses revealed significant positive correlations of the BMI, the serum total cholesterol and low-density lipoprotein cholesterol levels with the DNA methylation level (p = 0.0493, p = 0.003, and p = 0.0094, respectively). The study findings suggest an association between DNA methylation at the TSPOAP1-AS1 promoter and overweight/obesity. Accordingly, methylation in this promoter region might be a potential predictor of obesity.

scholarly journals Impact of Infrasound on Methylation Status of Genome in Testes of Rats

2007 ◽  
Vol 26 (2) ◽  
pp. 143-147
Author(s):  
Li Rui-Man ◽  
Zhuang Zhi-Qiang ◽  
Yao Hai-Tao ◽  
Pei Zhao-Hui ◽  
Chen Jing-Zao
Keyword(s):  
Dna Methylation ◽  
Methylation Level ◽  
Dna Methyltransferase ◽  
Methylation Status ◽  
Control Groups ◽  
Methyltransferase Activity ◽  
Dynamic Changes ◽  
Time Points ◽  
Cpg Sites ◽  
Underlying Mechanisms

To probe into the changes induced by infrasonic exposure on the methylation status of the genome in testes and underlying mechanisms, we inspected the percentage of unmethylated CpG sites (an index for DNA methylation level) and DNA methyltransferase activity in testes of SD rats exposed to infrasound of 8Hz at 90dB or 130dB for 1, 7, 14 and 21 days (2h/d). Compared to control groups at the same time points, significantly decreased DNA methylation level and methyltransferase activity were observed in all but experimental groups of ld and 21d at 90dB ( p<0.05). Compared to 90dB groups at the same time points, DNA methylation level and DNA methyltransferase activity at 130dB decreased more significantly ( p<0.05). The patterns of dynamic changes on the percentage of unmethylated CpG sites and methyltransferase activity at 130dB were different from those at 90dB. The results indicated that infrasonic exposure induced epigenetic changes in testes of rats, which depended on parameters of infrasonic exposure.

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