Screening for differential methylation status in fetal myocardial tissue samples with ventricular septal defects by promoter methylation microarrays

Epidemiological studies have reported the relationship between bisphenol A (BPA) exposure and increased prevalence of asthma, but the mechanisms remain unclear. Here, we investigated whether BPA exposure and DNA methylation related to asthma in children. We collected urinary and blood samples from 228 children (Childhood Environment and Allergic Diseases Study cohort) aged 3 years. Thirty-three candidate genes potentially interacting with BPA exposure were selected from a toxicogenomics database. DNA methylation was measured in 22 blood samples with top-high and bottom-low exposures of BPA. Candidate genes with differential methylation levels were validated by qPCR and promoter associated CpG islands have been investigated. Correlations between the methylation percentage and BPA exposure and asthma were analyzed. According to our findings, MAPK1 showed differential methylation and was further investigated in 228 children. Adjusting for confounders, urinary BPA glucuronide (BPAG) level inversely correlated with MAPK1 promoter methylation (β = −0.539, p = 0.010). For the logistic regression analysis, MAPK1 methylation status was dichotomized into higher methylated and lower methylated groups with cut off continuous variable of median of promoter methylation percentage (50%) while performing the analysis. MAPK1 methylation was lower in children with asthma than in children without asthma (mean ± SD; 69.82 ± 5.88% vs. 79.82 ± 5.56%) (p = 0.001). Mediation analysis suggested that MAPK1 methylation acts as a mediation variable between BPA exposure and asthma. The mechanism of BPA exposure on childhood asthma might, therefore, be through the alteration of MAPK1 methylation. The mechanism of BPA exposure on childhood asthma might, therefore, be through the alteration of MAPK1 methylation.

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MGMT methylation in newly-diagnosed glioblastoma multiforme (GBM): From the S0001 phase III study of radiation therapy (RT) and O6-benzylguanine, (O6BG) plus BCNU versus RT and BCNU alone for newly diagnosed GBM

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.1512 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 1512-1512 ◽

Cited By ~ 2

Author(s):

D. T. Blumenthal ◽

M. Wade ◽

C. J. Rankin ◽

F. Fitzpatrick ◽

K. Stelzer ◽

...

Keyword(s):

Glioblastoma Multiforme ◽

Median Survival ◽

Promoter Methylation ◽

Promoter Region ◽

Alkylating Agents ◽

Methylation Status ◽

Phase Iii ◽

Newly Diagnosed ◽

Tissue Samples ◽

Mgmt Promoter

1512 Background: Glioblastoma multiforme (GBM) is a high grade primary brain neoplasm associated with a median survival of less than a year. Historically, one-third of patients seem to benefit from treatment with alkylating chemotherapy. This minority may correspond to a population with decreased levels of active O6-methylguanine- methyltransferase enzyme (MGMT). MGMT repairs tumor DNA damaged by chemotherapy, allowing continued replication after exposure to treatment. Patients with low tumor MGMT activity may be more likely to respond to alkylating treatment. Hypermethylation of the MGMT promoter region leads to decreased transcription of the enzyme and is associated with improved outcome in GBM patients treated with radiation and alkylating chemotherapy. Methods: We studied a patient cohort with newly diagnosed GBM registered on Southwest Oncology Group protocol S0001, a phase III randomized, two arm clinical trial investigating an inhibitor of MGMT (O6-benzylguanine, O6BG). Both groups received standard radiation and BCNU (carmustine). The experimental group additionally received O6BG. We determined polymerase chain reaction (PCR) methylation status of the promoter region of MGMT in 88 patients with adequate tissue samples. In 41 cases, we were able to obtain successful PCR results. Results: 28 of 41 samples (68%) were found to be unmethylated and 13 of 41 (32%, 95% c. i. 18% to 50%) were methylated. Patients with methylated MGMT had a median survival of 12.6 months (95% c.i. of 7.8–15.8 months). Patients with unmethylated MGMT had a median survival of 10.6 months (95% c.i. of 8.7–12.0 months). Median progression-free survivals were 4.5 and 3.1 months respectively, for the methylated and unmethylated groups. Conclusions: This result is consistent with prior studies which showed that approximately two-thirds of patients express MGMT, and accordingly, are resistant to alkylating agents. The subgroup of patients without promoter methylation may be more likely to benefit from treatment with O6BG. Analysis of MGMT promoter methylation status per study treatment group, and correlation with median survival and progression-free survival will be presented. No significant financial relationships to disclose.

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Aberrant methylation of tumour suppressor genes WT1, GATA5 and PAX5 in hepatocellular carcinoma

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2015-1198 ◽

2016 ◽

Vol 54 (12) ◽

Cited By ~ 8

Author(s):

Martin Mžik ◽

Marcela Chmelařová ◽

Stanislav John ◽

Jan Laco ◽

Ondřej Slabý ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Promoter Methylation ◽

Mrna Level ◽

Methylation Status ◽

Tumour Suppressor ◽

Tumour Suppressor Genes ◽

Aberrant Methylation ◽

Suppressor Genes ◽

Tissue Samples ◽

Differentially Methylated Genes

AbstractBackground:Aberrant hypermethylation of tumour suppressor genes (TSGs) occurring in hepatocellular carcinoma (HCC) could provide a mean of molecular characterisation of this cancer. The aim of this study was to investigate promoter methylation and gene expression of selected TSGs in HCC to identify candidate genes for further validation as potential biomarkers.Methods:Methylation-specific multiplex ligation-dependent probe amplification method was used to measure the methylation status of 25 TSGs in 49 HCC samples and 36 corresponding non-cancerous liver tissue samples. Relative expression of the differentially methylated genes was assessed at the mRNA level using quantitative PCR.Results:We observed a significantly higher methylation in genesConclusions:HCC evince aberrant promoter methylation of

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Analysis of Promoter Methylation, Polymorphism and Expression Prole of Cytotoxic T-Lymphocyte-Associated Antigen-4 in Patients with Gastric Cancer

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.233.dmkt ◽

2014 ◽

Vol 23 (3) ◽

pp. 249-253 ◽

Cited By ~ 6

Author(s):

Dor Mohammad Kordi-Tamandani ◽

Shahrbbanou Karimi Davani ◽

Taybeh Baranzehi ◽

Simin Hemati

Keyword(s):

Gastric Cancer ◽

T Cell Activation ◽

T Lymphocyte ◽

Promoter Methylation ◽

Cytotoxic T Lymphocyte ◽

Methylation Status ◽

Cancer Tissue ◽

Tissue Samples ◽

Increased Risk ◽

Ctla4 Gene

AbstractBackground & Aim: Cytotoxic T lymphocyte-associated antigen-4 (CTLA4) is a crucial immune-checkpoint receptor regulating T-cell activation. The current study was carried out to evaluate the function of CTLA4 gene in patients with gastric cancer.Methods: The methylation of CTLA4 gene promoter was evaluated by methylation-specific polymerase chain reaction (MSP) technique using 85 paraffin-embedded gastric cancer tissue samples and normal tissue on the tumor margins as control tissue samples. Expression analysis was performed on paraffin-embedded tissue samples (25 each of cancerous and normal tissues) using Real-time PCR.Results: Statistically significant differences were observed between the tumor and margin-cell areas withrespect to promoter methylation status (OR = 4.829, 95% CI: 2.46-9.48, p < 0.001) and CTLA4 expression profile (mean ± SD = 7.56 ± 17.35, p = 0.04).Conclusion: To the best of our knowledge, the current study is the first one highlighting the association between promoter hypermethylation of CTLA4 gene, decreased CTLA4 expression, and increased risk of gastric cancer.

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Decreased mRNA and protein expression of TWIST1 in myocardial tissue of fetuses with ventricular septal defects

Molecular Medicine Reports ◽

10.3892/mmr.2015.3734 ◽

2015 ◽

Vol 12 (2) ◽

pp. 3089-3094

Author(s):

YUTING WANG ◽

QIDI WANG ◽

CHANGLONG GUO ◽

SHUO WANG ◽

YUE QIU ◽

...

Keyword(s):

Protein Expression ◽

Myocardial Tissue ◽

Ventricular Septal Defects ◽

Septal Defects ◽

Mrna And Protein Expression

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Molecular Genetics of Esophageal Cancer : Indian Perspective

Asian Pacific Journal of Cancer Biology ◽

10.31557/apjcb.2021.6.2.155-160 ◽

2021 ◽

Vol 6 (2) ◽

pp. 155-160

Author(s):

Suddhasattwa Ray ◽

Mona Malekzadehmoghani ◽

Sonia S Ray ◽

Partha Sen ◽

Sayan Chakraborty

Keyword(s):

Promoter Methylation ◽

Methylation Status ◽

Cpg Islands ◽

Stage Iv ◽

Tissue Samples ◽

Cpg Dinucleotides ◽

Specific Pcr ◽

Significant Difference ◽

Indian Perspective

Background: RIZ1 is one of the tumor-suppressor genes that is silenced in many human cancers. Change in RIZ1 expression has not been reported in ESCC patients. Therefore, the aim of this study was to investigate the role of RIZ1 in ESCC in the Indian population. Methods: Twelve esophageal squamous-cell carcinoma (ESCC) patients in stage IV and 12 healthy individuals were used in this study. Tissue sampling was taken from individuals and total RNA was isolated and then cDNA was synthesized using PCR. RIZ1 primers were then designed, and RIZ1 expression was quantified by qRT-PCR. Mapping of CpG islands in RIZ1 promoter was performed using bioinformatics tools. The promoter methylation status of this gene was studied using u methylation-specific PCR (MSP). T-student test was used to analyze the data.Results: Decreased RIZ1 expression was observed in ESCC compared with healthy controls. The results showed a relatively higher density of CpG dinucleotides in the RIZ1 promoter. No significant difference in promoter methylation was observed in blood and tissue samples.Conclusion: The study showed a significant down-regulation of RIZ-1 gene in the blood and tissue samples of ESCC patients that did not related to the altered promoter methylation.

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Synergic effect of diabetes mellitus and H. pylori infection on proliferation of cells via downregulating the expression of PTEN by hypermethylating its promoter region

10.21203/rs.3.rs-20761/v1 ◽

2020 ◽

Author(s):

Huibin Lu ◽

Xinwei Han ◽

Jianzhuang Ren ◽

Kewei Ren ◽

Zongming Li ◽

...

Keyword(s):

Diabetes Mellitus ◽

Gastric Cancer ◽

Dna Methylation ◽

Promoter Methylation ◽

Methylation Status ◽

Suppressor Gene ◽

Tissue Samples ◽

Tumor Tissues ◽

Pten Mrna ◽

H Pylori

Abstract Background It has been reported that CagA of H. pylori reduced the expression of PTEN by enhancing its promoter methylation. Furthermore, DM may also promote the methylation status of PTEN, a tumor suppressor gene in Gastric cancer. It is intriguing to explore whether DM may strengthen the tumorigenic effect of HP by promoting the methylation of PTEN promoter and whether the administration of metformin may reduce the risk of GC by suppressing the methylation of PTEN promoter. Methods Bisulfite sequencing PCR was performed to measure the DNA methylation of PTEN promoter in GC patients and HGC-27 cells treated under different conditions. Quantitative real-time PCR was carried out to measure the expression of PTEN mRNA. Immunohistochemistry and Western blot were used to evaluate the expression of PTEN protein. Immunofluorescence and flow cytometry were performed to analyze the apoptosis of GC tissue samples and HGC-27 cells treated under different conditions. MTT assay was carried out to examine the proliferation of HGC-27 cells. Results DNA methylation of PTEN promoter was synergetic enhanced by HP infection and Diabetes mellitus in patients with Gastric cancer. Accordingly, the expression of PTEN was suppressed in GC patients with HP infection and DM. Furthermore, cell apoptosis was decreased in GC patients with HP infection and DM. Metformin showed an apparent effect on maintaining CagA induced elevation of PTEN promoter methylation, thus attenuating the PTEN expression, increasing the proliferation and suppressing the apoptosis of HGC-27 cells. Conclusion In this study, we collected GC tumor tissues from GC patients with or without DM/HP to compare their PTEN methylation and expression while testing the effect of Metformin on the methylation of PTEN promoter. Our study provided evidence for the mechanism underlying the therapeutic role of Metformin in GC treatment.

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Methylation Assessment of Two DKK2 and DKK4 Genes in Oral Squamous Cell Carcinoma Patients

Iranian Journal of Public Health ◽

10.18502/ijph.v49i10.4698 ◽

2020 ◽

Author(s):

Sedigheh KHEIRANDISH ◽

Nosratollah ESHGHYAR ◽

Farzad YAZDANI ◽

Pouyan AMINI SHAKIB ◽

Ali HOSSEINI-BERESHNEH ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Oral Squamous Cell Carcinoma ◽

Wnt Signaling ◽

Cell Carcinoma ◽

Squamous Cell ◽

Promoter Methylation ◽

Methylation Status ◽

Wnt Signaling Pathway ◽

Healthy Controls ◽

Tissue Samples

Background: Oral squamous cell carcinoma (OSCC) is one of the most important types of oral malignancies. DKK gene family members as well as DKK2/4 have critical roles in regulation of Wnt signaling as one of the main determining pathway in oral carcinogenesis. This study aimed to identify promoter methylation status of DKK2/4 genes to provide possible biomarkers for early detection and treatment of OSCC patients. Methods: A case control study was performed on 31 fresh tissues obtained from oral cavity of patients affected by OSCC and 31 fresh corresponding tissues from normal healthy controls in Tehran and, between the years of 2016-2018. Purified DNA from tissue samples was subjected to bisulfite treatment and then methylation specific polymerase chain reaction (MSP-PCR) was carried out on treated DNA samples. Results: DKK4 promoter was methylated in none of OSCC samples while it was methylated in 16.1% of healthy controls. 16.1% of OSCC samples were detected to be semimethylated and 22.6% of healthy normal samples were methylated for DKK2 promoter gene. Meaningful difference was found in DKK4 promoter methylation among OSCC patients and healthy controls. Significant correlation was found between DKK4 promoter methylation and tumor grade. The age of all enrolled samples was demonstrated to have strong effect on promoter methylation of studied genes. Conclusion: Hypomethylation of DKK2 and DKK4 genes in higher grades of OSCC samples may indicate the pivotal role of their expression in tumor cells invasion and progression through modulation of Wnt signaling pathway. Further study required to determine simultaneous expression of those genes and Wnt signaling elements at mRNA and protein levels.

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