Clinical validation of a novel quantitative assay for the detection of MGMT methylation in glioblastoma patients

Abstract

Background The promoter hypermethylation of the methylguanine-DNA methyltransferase gene is a frequently used biomarker in daily clinical practice as it is associated with a favorable prognosis in glioblastoma patients treated with temozolamide. Due to the absence of adequately standardized techniques, international harmonization of the MGMT methylation biomarker is still an unmet clinical need for the diagnosis and treatment of glioblastoma patients. Results In this study we carried out a clinical validation of a quantitative assay for MGMT methylation detection by comparing a novel quantitative MSP using double-probe (dp_qMSP) with the conventional MSP in 100 FFPE glioblastoma samples. We performed both technologies and established the best cutoff for the identification of positive-methylated samples using the quantitative data obtained from dp_qMSP. Kaplan–Meier curves and ROC time dependent curves were employed for the comparison of both methodologies. Conclusions We obtained similar results using both assays in the same cohort of patients, in terms of progression free survival and overall survival according to Kaplan–Meier curves. In addition, the results of ROC(t) curves showed that dp_qMSP increases the area under curve time-dependent in comparison with MSP for predicting progression free survival and overall survival over time. We concluded that dp_qMSP is an alternative methodology compatible with the results obtained with the conventional MSP. Our assay will improve the therapeutic management of glioblastoma patients, being a more sensitive and competitive alternative methodology that ensures the standardization of the MGMT-biomarker making it reliable and suitable for clinical use.

Transcriptional epigenetic regulation of Fkbp1/Pax9 genes is associated with impaired sensitivity to platinum treatment in ovarian cancer

“…It is therefore necessary to explore the area of ​​epigenetic interest in additional human tumor cell lines to confirm the positions identified by next-generation sequencing that remain frequently methylated in cancer. Our bisulfite sequencing results not only confirmed the β values but also allowed for the design of high-sensitivity primers and double probes for these specific positions (by MSP or qMSP), ensuring their use in not only determining the percentage of demethylation after epigenetic reactivation treatment in our cellular model but also in patient paraffin samples, which supports the potential diagnostic use of the assay, as is the case for the FDA-approved epigenetic marker O6-methylguanine-DNA methyltransferase ( MGMT ) for routine clinical practice [ 25 ].…”

Clinical Impact of IDH1 Mutations and MGMT Methylation in Adult Glioblastoma Multiforme

“…Methylation status of MGMT is among the most studied molecular biomarkers in neuro-oncology because of its influence in therapeutic management of glioblastoma, thus its detection has been reported using different techniques [30]. However, debate remains about the most appropriate technique to be used, in the current study authors assessed methylation status using restriction enzyme that cut the unmethylated regions and hence the detected will be the methylated (REF).…”

Epigenetic Mechanisms Underlying COVID-19 Pathogenesis

“…Further, considering the ongoing promotion of precision medicine, it is difficult to adequately screen patients based on genetic mutations alone, and epigenetic information must also be used appropriately. In clinical practice, DNA methylation is used for diagnosis [ 146 ], and HDAC inhibitors and DNA methylation inhibitors are used as therapeutic agents [ 147 , 148 ]. Furthermore, clinical research and clinical trials of new drug types, such as histone methyltransferase inhibitors and histone demethylase inhibitors, are currently underway worldwide for clinical application [ 149 , 150 , 151 , 152 ].…”