title: Human herpesvirus multiplex ddPCR detection in brain tissue from low- and high-grade astrocytoma cases and controls.
abstract: BACKGROUND
  Glioblastoma (GBM) is a fatal CNS malignancy, representing 50 % of all gliomas with approximately 12-18 months survival time after initial diagnosis. Recently, the human herpesvirus cytomegalovirus (CMV) has been suggested to have an oncogenic role, yet this association remains controversial. In addition, human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) have also been associated with low-grade gliomas, but few studies have examined HHV-6 and EBV in glioblastomas. Droplet digital PCR (ddPCR) is a highly precise diagnostic tool that enables the absolute quantification of target DNA. This study examines the association between multiple human herpesviruses and astrocytomas.
  
  
  METHODS
  This study analyzed 112 brain tissue specimens, including 45 glioblastoma, 12 astrocytoma grade III, 2 astrocytoma grade II, 4 astrocytoma grade I, and 49 controls. All brain tissue samples were de-identified and pathologically confirmed. Each tissue block was sectioned for DNA extraction and CMV, EBV, HHV-6A and HHV-6B, and a cellular housekeeping gene were amplified by ddPCR.
  
  
  RESULTS
  Neither CMV nor HHV-6A were detected in any of the astrocytoma samples. However, HHV-6B (p = 0.147) and EBV (p = 0.049) had a higher positivity frequency in the GBM compared to the controls.
  
  
  CONCLUSIONS
  The undetectable CMV DNA in the astrocytoma cohort does not support the observation of an increased prevalence of CMV DNA in GBM, as reported in other studies. EBV has a significantly higher positivity in the GBM cohort compared to the controls, while HHV-6B has a higher but not statistically significant positivity in the case cohort. Whether these viruses play an oncogenic role in GBM remains to be further investigated.
authors.affiliation: The National Institute of Neurological Disorders and Stroke, National Institutes of Health, BG 10 RM 5C103 10 Center Dr., Bethesda, MD 20892 USA ; School of Medicine and Health Sciences, The George Washington University, Ross Hall 2300 Eye Street, NW, Washington, DC 20037 USA.
authors.forename: Cheng-Te Major
authors.initials: CT
authors.lastname: Lin
authors.affiliation: The National Institute of Neurological Disorders and Stroke, National Institutes of Health, BG 10 RM 5C103 10 Center Dr., Bethesda, MD 20892 USA ; School of Medicine and Health Sciences, The George Washington University, Ross Hall 2300 Eye Street, NW, Washington, DC 20037 USA.
authors.forename: Emily C
authors.initials: EC
authors.lastname: Leibovitch
authors.affiliation: School of Medicine and Health Sciences, The George Washington University, Ross Hall 2300 Eye Street, NW, Washington, DC 20037 USA.
authors.forename: M Isabel
authors.initials: MI
authors.lastname: Almira-Suarez
authors.affiliation: The National Institute of Neurological Disorders and Stroke, National Institutes of Health, BG 10 RM 5C103 10 Center Dr., Bethesda, MD 20892 USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Jacobson
keywords: Astrocytoma; CMV; EBV; Glioblastoma; HHV-6A; HHV-6B; Herpesvirus; ddPCR