Demonstration of methyl guanine methyl transferase promoter methylation in glioblastomas by polymerase chain reaction method, correlation of clinical and histopathological prognostic factors

Aim: The aim of this study is to evaluate the mutation on promoter region of Methyl Guanine Methyl Transferase (MGMT) gene, the role of tumor pathogenesis and to detect correlation of clinical and histopathological prognostic factors. As a result of this, temozolamide therapy may be intended for manangement of those patients.Material and Methods: The glioblastoma cases which were diagnosed in Cukurova University Faculty of Medicine Department of Pathology between 2008-2011 were reviewed retrospectively, 55 cases were selected for the study. All cases were evaluated for age, gender and survival time. Also tumor localization, subtype, histomorphologic features: necrosis, vascular endothelial proliferation and immunohistochemical staining for p53, Epidermal growth factor receptor (EGFR), Ki-67 staining results were evaluated. The presence of methylation in the MGMT promoter region was investigated by Polymerase Chain Reaction (PCR) method. The results were statistically analysed in Cukurova University, Faculty of Medicine, Department of Biostatistics.Results: There was no statistically significant difference between age, gender, location, histomorphologic features, immunohistochemical parameters: Ki-67, EGFR and survival time (p> 0.05). Immunohistochemical p53 staining was statistically significant with survey (p = 0.003). Thirty two of fifty five cases (58.2 %) had methylated MGMT DNA and 23 cases of them (41.8 %) had unmethylated MGMT DNA. The patients without methylated MGMT DNA had longer survival compared to methylated group (p= 0.002).Conclusion: It was concluded that in order to demonstrate the expected predictive and prognostic factors in patients who would take alkylating chemotherapeutic agent for glioblastoma, evaluating the presence of methylation of MGMT promoter region with PCR might be a useful method.