PCR-Based Study for Molecular Documentation of Neuropersistence of Human Herpes Virus Type - 6 in a Group of Patients with Brain Cancers in Mid-Euphrates Sector of Iraq

Background: The extent of tissue tropism in persistent Human Herpesvirus-6 (HHV-6) infection is not known but this virus has predominantly localized in T- lymphocytes. Recently, researches have reported glial tropism of HHV-6 in neural tissues and an association with a diverse spectrum of CNS diseases, including tumors. Objective: Investigate the neuropersistence- detection rate of HHV-6 along brain tumorigenesis in a series of brain tumor tissues of a group of Iraqi patients in Mid-Euphrates Sector/ Iraq. Patients and methods: Seventy freshly obtained- brain tissues were enrolled in this study; (50) were brain cancer biopsies and (20) autopsies obtained from apparently normal brain (as a control group). Conventional PCR was chosen for the detection of HHV-6. Results: According to PCR detection, 12 out of 30 (40%) of the specimens revealed PCR detection positivity for HHV-6, while 18 out of 30 (60%) specimens showed negative- detection for HHV-6. The brain tumor tissues which were most HHV6- infected are related to the age stratum (21-40 years), accounted for 8 % , while the age strata (3- 20 years), (41-60 years), and (61-80 years) each accounted for 6 %; 6% and 4 %, respectively. The percentage of brain tumor tissues that have positive HHV-6 PCR results according to the gender of patients, where the males accounting for 66.7% (8 out of 12 cases) and females accounting for 33.3% (4 out of 12 cases). Positive HHV-6-PCR detection results in brain tissues from patients according to various types of brain tumors were 8%, 6%, 6%, 2%, and 2% in Glioma; Oligodendroglioma; Ganglioglioma; Meningioma, and Medulloblastoma, respectively. Conclusion: In view of the relatively small numbers included in our study, the present results indicate the possibility that HHV-6 may play a role in the tumor biology of the examined subset of brain tumors and may contributed to their development.