scholarly journals Correlation of O6-Methylguanine Methyltransferase (MGMT) Promoter Methylation With Clinical Outcomes in Glioblastoma and Clinical Strategies to Modulate MGMT Activity

2008 ◽  
Vol 26 (25) ◽  
pp. 4189-4199 ◽  
Author(s):  
Monika E. Hegi ◽  
Lili Liu ◽  
James G. Herman ◽  
Roger Stupp ◽  
Wolfgang Wick ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Tumor Tissue ◽  
Alkylating Agents ◽  
Malignant Gliomas ◽  
Chemotherapy Resistance ◽  
Mgmt Promoter Methylation ◽  
Hematologic Toxicity ◽  
Major Mechanism ◽  
Mgmt Promoter ◽  
Methylguanine Methyltransferase

Resistance to alkylating agents via direct DNA repair by O6-methylguanine methyltransferase (MGMT) remains a significant barrier to the successful treatment of patients with malignant glioma. The relative expression of MGMT in the tumor may determine response to alkylating agents, and epigenetic silencing of the MGMT gene by promoter methylation plays an important role in regulating MGMT expression in gliomas. MGMT promoter methylation is correlated with improved progression-free and overall survival in patients treated with alkylating agents. Strategies to overcome MGMT-mediated chemoresistance are being actively investigated. These include treatment with nontoxic pseudosubstrate inhibitors of MGMT, such as O6-benzylguanine, or RNA interference-mediated gene silencing of MGMT. However, systemic application of MGMT inhibitors is limited by an increase in hematologic toxicity. Another strategy is to deplete MGMT activity in tumor tissue using a dose-dense temozolomide schedule. These alternative schedules are well tolerated; however, it remains unclear whether they are more effective than the standard dosing regimen or whether they effectively deplete MGMT activity in tumor tissue. Of note, not all patients with glioblastoma having MGMT promoter methylation respond to alkylating agents, and even those who respond will inevitably experience relapse. Herein we review the data supporting MGMT as a major mechanism of chemotherapy resistance in malignant gliomas and describe ongoing studies that are testing resistance-modulating strategies.

scholarly journals MGMT-Methylation in Non-Neoplastic Diseases of the Central Nervous System

2021 ◽  
Vol 22 (8) ◽  
pp. 3845
Author(s):  
Sarah Teuber-Hanselmann ◽  
Karl Worm ◽  
Nicole Macha ◽  
Andreas Junker
Keyword(s):  
Promoter Methylation ◽  
Dna Methyltransferase ◽  
Alkylating Agents ◽  
Malignant Gliomas ◽  
Mgmt Promoter Methylation ◽  
Demyelinating Diseases ◽  
Brain Diseases ◽  
Tumor Biomarker ◽  
Mgmt Promoter ◽  
First Time

Quantifying O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation plays an essential role in assessing the potential efficacy of alkylating agents in the chemotherapy of malignant gliomas. MGMT promoter methylation is considered to be a characteristic of subgroups of certain malignancies but has also been described in various peripheral inflammatory diseases. However, MGMT promoter methylation levels have not yet been investigated in non-neoplastic brain diseases. This study demonstrates for the first time that one can indeed detect slightly enhanced MGMT promoter methylation in individual cases of inflammatory demyelinating CNS diseases such as multiple sclerosis and progressive multifocal leucencephalopathy (PML), as well as in other demyelinating diseases such as central pontine and exptrapontine myelinolysis, and diseases with myelin damage such as Wallerian degeneration. In this context, we identified a reduction in the expression of the demethylase TET1 as a possible cause for the enhanced MGMT promoter methylation. Hence, we show for the first time that MGMT hypermethylation occurs in chronic diseases that are not strictly associated to distinct pathogens, oncogenic viruses or neoplasms but that lead to damage of the myelin sheath in various ways. While this gives new insights into epigenetic and pathophysiological processes involved in de- and remyelination, which might offer new therapeutic opportunities for demyelinating diseases in the future, it also reduces the specificity of MGMT hypermethylation as a tumor biomarker.

Multiple Assays to Determine Methylguanine-Methyltransferase Status in Lung Carcinoids and Correlation with Clinical and Pathological Features

2019 ◽  
Vol 110 (1-2) ◽  
pp. 1-9
Author(s):  
Simona Vatrano ◽  
Jessica Giorcelli ◽  
Arianna Votta ◽  
Guendalina Capone ◽  
Stefania Izzo ◽  
...  
Keyword(s):  
Gene Expression ◽  
Promoter Methylation ◽  
Alkylating Agents ◽  
Mgmt Promoter Methylation ◽  
High Grade ◽  
Pathological Features ◽  
Mgmt Gene ◽  
Mgmt Promoter ◽  
Methylguanine Methyltransferase ◽  
Clinical And Pathological Features

Background: O6-methylguanine-methyltransferase (MGMT) is a key enzyme for the DNA repair machinery strongly associated with response to alkylating agents in different tumors. Data on its expression and related clinical impact in neuroendocrine tumors are limited to the gastro-entero-pancreatic system, with controversial results in terms of prognostic or predictive value. In lung carcinoids, although clinical efficacy of alkylating agents has been shown in small studies, very few data to date are available on MGMT status. Objective: To assess MGMT status in lung carcinoids using multiple assays and to compare data with major clinical and pathological features. Methods: A retrospective series of 95 lung carcinoids and 51 control cases of high-grade neuroendocrine lung carcinomas was analyzed for MGMT promoter methylation, MGMT gene expression, and MGMT protein expression using pyrosequencing, quantitative real-time PCR, and immunohistochemistry, respectively. Results: MGMT protein expression was inversely correlated with MGMT promoter methylation and positively with MGMT gene expression. MGMT promoter methylation progressively increased from carcinoids to high-grade carcinomas. In the carcinoid group, decreased MGMT gene expression was significantly associated with aggressive features (atypical histotype, grade G2, larger tumor size, higher T stage, and positive nodal status) but not with survival. MGMT promoter methylation was associated with lower stage and negative nodal status. Conclusions: Our study investigated MGMT status in a large series of lung carcinoids in the attempt to move forward a rational use of alkylating agents in these tumors. Interestingly, low MGMT gene expression defines a subgroup of lung carcinoids with aggressive features.

scholarly journals Treatment of recurrent malignant gliomas with fotemustine monotherapy: impact of dose and correlation with MGMT promoter methylation

BMC Cancer ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Alessandra Fabi ◽  
Giulio Metro ◽  
Michelangelo Russillo ◽  
Antonello Vidiri ◽  
Carmine Maria Carapella ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Malignant Gliomas ◽  
Mgmt Promoter Methylation ◽  
Mgmt Promoter

MGMT Promoter Methylation as an Epigenetic Biomarker for the Estimation of Chemosensitivity towards the Alkylating Agents Based Chemotherapies

2017 ◽  
Vol 17 ◽  
pp. S391-S392
Author(s):  
Natalia Cucu ◽  
V. Constantinescu ◽  
Lilia Matei ◽  
Mihaela Dragomir ◽  
Silvia Aposteanu ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Alkylating Agents ◽  
Mgmt Promoter Methylation ◽  
Mgmt Promoter ◽  
Epigenetic Biomarker

Detection of MGMT promoter methylation in malignant gliomas.

2016 ◽  
Vol 34 (15_suppl) ◽  
pp. e23131-e23131
Author(s):  
Michelle Afkhami ◽  
Vandana Sharma ◽  
Maria Cuellar ◽  
Massimo D'Apuzzo ◽  
Behnam Badie ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Malignant Gliomas ◽  
Mgmt Promoter Methylation ◽  
Mgmt Promoter

Impact of predictive impact of MGMT promoter methylation in malignant astrocytomas depends on the methylation subgroup.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 2013-2013
Author(s):  
Wolfgang Wick ◽  
Tobias Kessler ◽  
Michael Platten ◽  
Christoph Meisner ◽  
Michael Bamberg ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Malignant Gliomas ◽  
Predictive Biomarker ◽  
Copy Number Variations ◽  
Mgmt Promoter Methylation ◽  
Published Data ◽  
Global Methylation ◽  
Methyl Transferase ◽  
Mgmt Promoter

2013 Background: O6-methylguanine DNA-methyl transferase (MGMT) status is predictive for alkylating chemotherapy in most series, but there are non-benefitting subgroups. Despite multiple attempts, MGMT has not been unambiguously established as a predictive biomarker for patients with malignant gliomas. Further, these tumors are to be better classified according to global methylation profiles. Methods: Long-term efficacy data of the NOA-08 trial (NCT01502241) that compared efficacy and safety of radiotherapy (RT, n= 176) to temozolomide (TMZ, n= 193) in patients > 65 years with anaplastic astrocytoma (AA) or GB as well as genome-wide DNA methylation patterns and copy number variations assessed by methylation arrays in a biomarker subset ( n= 104) and an independent cohort ( n= 380) have been used to assess the interaction between MGMT status and methylation subgroups. Results: In the long-term update of NOA-08 patients with MGMT methylated tumors had longer OS and EFS when treated with TMZ (18.4 [13.9-24.4] months and 8.5 [6.9-13.3] months) versus RT (9.6 [6.4-13.7] months and 4.8 [4.3-6.2] months, HR 0.44 [0.27-0.70], p < 0.001 for OS and 0.46 [0.29-0.73], p = 0.001 for EFS). These data compared favorably with recently published data from patients treated with chemoradiation (Perry et al. NEJM 2017). Importantly, only patients with glioblastomas of the methylation class receptor tyrosine kinase II (RTKII) and mesenchymal but not RTK I demonstrated the predictive impact of MGMT in the NOA and the independent validation cohort. Conclusions: MGMT promoter methylation as a strong but methylation subclass-dependent predictive biomarker for the use of alkylating chemotherapy in malignant gliomas. The data call for embedding of MGMT tests into global methylation analyses for all patients with malignant gliomas potentially treated with alkylating chemotherapy.

MGMT promoter methylation in malignant gliomas

2010 ◽  
Vol 5 (3) ◽  
pp. 161-165 ◽  
Author(s):  
Markus J. Riemenschneider ◽  
Monika E. Hegi ◽  
Guido Reifenberger
Keyword(s):  
Promoter Methylation ◽  
Malignant Gliomas ◽  
Mgmt Promoter Methylation ◽  
Mgmt Promoter

scholarly journals Immunotherapeutic early-phase clinical trials and malignant gliomas: a single-center experience and comprehensive immunophenotyping of circulating leukocytes

2021 ◽  
Author(s):  
Matteo Simonelli ◽  
Pasquale Persico ◽  
Arianna Capucetti ◽  
Claudia Carenza ◽  
Sara Franzese ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Promoter Methylation ◽  
Early Phase ◽  
Univariate Analysis ◽  
Malignant Gliomas ◽  
Mgmt Promoter Methylation ◽  
Control Group ◽  
Large Expansion ◽  
Mgmt Promoter ◽  
Early Phase Clinical Trials

Abstract Background Immunotherapeutic early-phase clinical trials (ieCTs) increasingly adopt large expansion cohorts exploring novel agents across different tumor types. High-grade glioma (HGG) patients are usually excluded from these trials. Methods Data of patients with recurrent HGGs treated within multicohort ieCTs between February 2014 and August 2019 (experimental group, EG) at our Phase I Unit were retrospectively reviewed and compared to a matched control group (CG) of patients treated with standard therapies. We retrospectively evaluated clinical, laboratory, and molecular parameters through univariate and multivariate analysis. A prospective characterization of circulating leukocyte subpopulations was performed in the latest twenty patients enrolled in the EG, with a statistical significance cutoff of p &lt;0.1. Results Thirty HGG patients were treated into six ieCTs. Fifteen patients received monotherapies (anti PD-1, anti CSF-1R, anti TGFβ, anti cereblon), fifteen patients combination regimens (anti PD-L1 + anti CD38, anti PD-1 + anti CSF-1R). In the EG, median progression-free survival and overall survival (OS) from treatment initiation were 1.8 and 8.6 months; twelve patients survived more than 12 months, and two of them more than six years. Univariate analysis identified O 6-methylguanine DNA methyltransferase (MGMT) promoter methylation and total protein value at six weeks as significantly correlated with a better outcome. Decreased circulating neutrophils and increased conventional dendritic cells levels lead to significantly better OS. Conclusions A subgroup of EG patients achieved remarkably durable disease control. MGMT promoter methylation identifies patients who benefit more from immunotherapy. Monitoring dynamic changes of innate immune cell populations may help to predict clinical outcomes.

O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation and relation to 1p/19q loss in low grade gliomas: A GICNO study

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 20064-20064 ◽  
Author(s):  
L. Nicolardi ◽  
R. Bertorelle ◽  
L. Bonaldi ◽  
A. Compostella ◽  
A. Roma ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Dna Methyltransferase ◽  
Alkylating Agents ◽  
Methylation Status ◽  
Mgmt Promoter Methylation ◽  
Low Grade ◽  
Tumor Localization ◽  
Response To Chemotherapy ◽  
Mgmt Promoter ◽  
The Impact

20064 Background: 1p and 19q deletions have been associated with a favorable response to chemotherapy and a good prognosis in patients (pts) with oligodendroglioma. MGMT promoter methylation has been associated with a longer survival in pts with glioblastoma who receive alkylating agents. As yet, there are no data on the expression of MGMT, and on the relationship between 1p/19q deletions and MGMT promoter methylation in low grade glioma (LGG). Methods: Pts that received a first line chemotherapy regimen with temozolomide for progressive LGG were enrolled in the study, designed to investigate the correlation between MGMT methylation status and 1p/19q deletions in this setting. 1p/19q deletions were analysed by FISH, and MGMT promoter methylation by methylation specific PCR (MSP). Results: Seventy-five pts (26 females, 49 males; median age 42 years: range 22–68 years) were accrued. Of these, 48 (64%) had oligodendrogliomas (O), 19 (25.3%) astrocytomas (A), and 8 (10.6%) oligoastrocytomas (OA); 44 (58.7%) had a history of epilepsy, 41 (54.7%) had a frontal tumor localization, 27 (36%) had MRI contrast enhancing lesions, and 35 (46.7%) had been pre-treated with radiotherapy. 1p/19q deletions, evaluable in 58 pts (77.3%), were both present in 36 pts (62%), (3 being A and 2 OA); 18 pts (31%) had no loss; 1 pt (1.7%) had 1p loss; 3 pts (5.2%) 19q loss. Combined 1p and 19q loss was not correlated with a frontal localization (p = 0.12), median age (0.47) and/or gender (0.62). MGMT promoter methylation, present in 17 (56.6%) of 30 assessable cases, was significantly associated with combined 1p/19q deletions (p = 0.03). MGMT promoter methylation was not significantly associated with age (p = 0.46), gender (p = 0.2), tumor localization (p = 0.12) and/or histology (0.37). Conclusions: 1p/19q deletions are strictly correlated to histology and to MGMT promoter methylation; further prospective trials are required to clarify the impact of these molecular signatures on clinical outcome. No significant financial relationships to disclose.

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