DNA expression of human cytomegalovirus in glioma and its prognostic significance

Abstract

Objective To explore the DNA expression of human cytomegalovirus (HCMV) in glioma and the association between HCMV infection and prognosis of glioma patients. Methods Used for this study were 89 specimens of glioma which had been surgically ablated and pathologically confirmed from the patients between January 2007 and December 2016 at Department of Neurosurgery, The First Affiliated Hospital of Zhengzhou University, and Department of Neurosurgery, The First Hospital of China Medical University. Of them, 32 belonged to WHO grade II, 31 to WHO grade III and 26 to WHO grade IV. Ten specimens of normal brain tissue were excised as controls from the contemporary patients receiving resection for essential epilepsy. Nested PCR was used to analyze the DNA expression of HCMV in the glioma tissue and normal brain tissue, and in the peripheral blood from the glioma and control patients. Prognosis of the glioma patients was evaluated using the Kaplan-Meier survival analysis. Results The DNA expression of HCMV was positive in 46 of the 89 specimens of glioma, involving 14 cases of WHO grade II, 16 ones of WHO grade III and 16 ones of WHO grade IV. The DNA expression of HCMV was negative in all the 10 specimens of normal brain tissue. There was a significant difference in the DNA expression of HCMV between the glioma tissue and normal brain tissue (P=0.002). The HCMV DNA was measured in the peripheral blood from 26 glioma patients, involving 10 cases of WHO grade II, 8 ones of WHO grade III and 8 ones of WHO grade IV. No HCMV DNA was detected in the peripheral blood from the 10 control patients. There was a significant difference between the brain glioma and control groups in gene expression of HCMV in peripheral blood(P=0.048). There were no significant differences in the survival rate between the patients with positive or negative DNA expression of HCMV in the glioma tissue or in the peripheral blood from the glioma and control patients (χ2=1.849, P=0.174; χ2=0.082, P=0.774). Conclusion HCMV infection may play an active role in pathogenesis and development of glioma. Key words: Human cytomegalovirus; Glioma; Nested PCR analysis