Pyrosequencing Analysis of MGMT Promoter Methylation in Meningioma.
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ABSTRACT:
SUBMITTER: Panagopoulos I
PROVIDER: S-EPMC6199576 | biostudies-literature | 2018 Sep-Oct
REPOSITORIES: biostudies-literature
Publications
Pyrosequencing Analysis of <i>MGMT</i> Promoter Methylation in Meningioma.
Panagopoulos Ioannis I Gorunova Ludmila L Leske Henning H Niehusmann Pitt P Johannessen Lene E LE Staurseth Julie J Øino Nina N Meling Torstein R TR Heim Sverre S Micci Francesca F Brandal Petter P
Cancer genomics & proteomics 20180901 5
<h4>Background</h4>Methylation of the O<sup>6</sup>-methylguanine-DNA methyltransferase (MGMT) gene promoter is a well-established predictor of response to the DNA-alkylating agent temozolomide in patients with glioblastoma.<h4>Materials and methods</h4>Pyrosequencing analysis was used to determine the MGMT promoter methylation status in 61 meningiomas, to clarify whether it might have a predictive role.<h4>Results</h4>Only two tumors (3%) had a mean methylation frequency higher than the cut-off ...[more]
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Project description:BackgroundO(6)-methylguanine-DNA methyltransferase (MGMT) is one of most important DNA repair enzyme against common carcinogens such as alkylate and tobacco. Aberrant promoter methylation of the gene is frequently observed in non-small cell lung cancer (NSCLC). However, the importance of epigenetic inactivation of the gene in NSCLC published in the literature showed inconsistence. We quantified the association between MGMT promoter methylation and NSCLC using a meta-analysis method.MethodsWe systematically reviewed studies of MGMT promoter methylation and NSCLC in PubMed, EMBASE, Ovid, ISI Web of Science, Elsevier and CNKI databases and quantified the association between MGMT promoter methylation and NSCLC using meta-analysis method. Odds ratio (OR) and corresponding 95% confidence interval (CI) were calculated to evaluate the strength of association. Potential sources of heterogeneity were assessed by subgroup analysis and meta-regression.ResultsA total of 18 studies from 2001 to 2011, with 1, 160 tumor tissues and 970 controls, were involved in the meta-analysis. The frequencies of MGMT promote methylation ranged from 1.5% to 70.0% (median, 26.1%) in NSCLC tissue and 0.0% to 55.0% (median, 2.4%) in non-cancerous control, respectively. The summary of OR was 4.43 (95% CI: 2.85, 6.89) in the random-effects model. With stratification by potential source of heterogeneity, the OR was 20.45 (95% CI: 5.83, 71.73) in heterogeneous control subgroup, while it was 4.16 (95% CI: 3.02, 5.72) in the autologous control subgroup. The OR was 5.31 (95% CI: 3.00, 9.41) in MSP subgroup and 3.06 (95% CI: 1.75, 5.33) in Q-MSP subgroup.ConclusionThis meta-analysis identified a strong association between methylation of MGMT gene and NSCLC. Prospective studies should be required to confirm the results in the future.
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