Predictive value of MGMT promoter methylation status in Asian and Caucasian patients with malignant gliomas: a meta-analysis

Background: The prognostic significance of O6-methylguanine-DNA methyltransferase (MGMT) promoter status for survival of patients with malignant gliomas remains controversial. Thus, the meta-analysis was performed in order to identify the impact of MGMT expression on prognosis of malignant gliomas. Method: An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases. Version 12.0 STATA software was used for the current meta-analysis. Hazard ratios (HRs) with their corresponding 95% confidence interval (95% CI) were also calculated to clarify the correlation between MGMT expression and the prognosis of malignant gliomas. Results: Final analysis of 2,377 malignant gliomas patients from 32 clinical studies was performed. The meta-analysis results show that MGMT promoter group and unmethylated MGMT group has a significant difference (all P < 0.01). Combined HR of MGMT suggests that the methylated MGMT group has a longer overall survival than the unmethylated MGMT group (P < 0.01), but the Asians don't present a difference between the two groups. Conclusion: The meta-analysis study shows that the elevated MGMT promoter group may have a better prognosis in malignant gliomas patients, but the Asians don't have a better prognosis.