MGMT promoter methylation in gliomas-assessment by pyrosequencing and quantitative methylation-specific PCR

Journal of Translational Medicine

Research

Guro Elisabeth Lind¹  Merete Hektoen¹  Hilde Honne¹  Ragnhild A Lothe²  Torstein Ragnar Meling³  David Scheie⁴  Eirik Helseth⁵  Petter Brandal⁶  Sverre Heim⁷  Hanne-Sofie Spenning Dahlback⁷  Annette Bentsen Håvik⁸ 

[1] Department of Cancer Prevention, Institute for Cancer Research, Oslo University Hospital-The Norwegian Radium Hospital, Oslo, Norway;Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway;Department of Cancer Prevention, Institute for Cancer Research, Oslo University Hospital-The Norwegian Radium Hospital, Oslo, Norway;Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway;Cancer stem cell innovation center, Oslo University Hospital, Oslo, Norway;Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway;Department of Pathology, Oslo University Hospital-Rikshospitalet, Oslo, Norway;Faculty of Medicine, University of Oslo, Oslo, Norway;Department of Neurosurgery, Oslo University Hospital-Ullevål Hospital, Oslo, Norway;Section for Cancer Cytogenetics, Institute for Medical Informatics, Oslo University Hospital-The Norwegian Radium Hospital, P.O. Box 4950, Nydalen, N-0424, Oslo, Norway;Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway;Department of Oncology, Oslo University Hospital-The Norwegian Radium Hospital, Oslo, Norway;Section for Cancer Cytogenetics, Institute for Medical Informatics, Oslo University Hospital-The Norwegian Radium Hospital, P.O. Box 4950, Nydalen, N-0424, Oslo, Norway;Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway;Faculty of Medicine, University of Oslo, Oslo, Norway;Section for Cancer Cytogenetics, Institute for Medical Informatics, Oslo University Hospital-The Norwegian Radium Hospital, P.O. Box 4950, Nydalen, N-0424, Oslo, Norway;Department of Cancer Prevention, Institute for Cancer Research, Oslo University Hospital-The Norwegian Radium Hospital, Oslo, Norway;Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway;Faculty of Medicine, University of Oslo, Oslo, Norway;

关键词: Glioma;    Glioblastoma;    MGMT;    Methylation;    Gene expression;    Low-grade glioma;    High-grade gliomas;    Pyrosequencing;    qMSP;    RT-PCR;   

DOI  :  10.1186/1479-5876-10-36

 received in 2011-09-19, accepted in 2012-03-06,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundMethylation of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter is a favorable prognostic factor in glioblastoma patients. However, reported methylation frequencies vary significantly partly due to lack of consensus in the choice of analytical method.MethodWe examined 35 low- and 99 high-grade gliomas using quantitative methylation specific PCR (qMSP) and pyrosequencing. Gene expression level of MGMT was analyzed by RT-PCR.ResultsWhen examined by qMSP, 26% of low-grade and 37% of high-grade gliomas were found to be methylated, whereas 97% of low-grade and 55% of high-grade gliomas were found methylated by pyrosequencing. The average MGMT gene expression level was significantly lower in the group of patients with a methylated promoter independent of method used for methylation detection. Primary glioblastoma patients with a methylated MGMT promoter (as evaluated by both methylation detection methods) had approximately 5 months longer median survival compared to patients with an unmethylated promoter (log-rank test; pyrosequencing P = .02, qMSP P = .06). One third of the analyzed samples had conflicting methylation results when comparing the data from the qMSP and pyrosequencing. The overall survival analysis shows that these patients have an intermediate prognosis between the groups with concordant MGMT promoter methylation results when comparing the two methods.ConclusionIn our opinion, MGMT promoter methylation analysis gives sufficient prognostic information to merit its inclusion in the standard management of patients with high-grade gliomas, and in this study pyrosequencing came across as the better analytical method.

【 授权许可】

Unknown   
© Håvik et al; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.