title: Quantitative analysis of cell-free Epstein-Barr virus DNA in the plasma of patients with peripheral T-cell and NK-cell lymphomas and peripheral T-cell proliferative diseases.
abstract: BACKGROUND
  The level of circulating EBV DNA is a prognostic marker in patients with some EBV-associated malignant diseases.
  
  
  OBJECTIVE
  To investigate the presence and nature of Epstein-Barr virus (EBV) DNA in the plasma and to evaluate the correlation of plasma concentrations of EBV DNA with the EBV genomic status in peripheral blood T-cells and neoplastic cells and with the clinical outcome of patients with peripheral T-cell and NK-cell lymphomas (PTCL) and peripheral T-cell proliferative diseases (PTPD).
  
  
  METHODS
  EBV DNA in the plasma of 45 patients and 45 controls was measured using real-time PCR. The presence of the EBV genome in the isolated peripheral blood lymphocytes (CD3+ and CD3- cells) was analysed by PCR. Detection of EBV-encoded early RNA (EBER) in corresponding tumor tissues was carried out using in situ hybridization. DNase I digestion was applied to plasma samples to detect naked EBV DNA.
  
  
  RESULTS
  Cell-free EBV DNA was detected in 32/38 (84%) of PTCL patients and 5/7 (71%) of PTPD patients, but not in the controls. Patients with EBV genome in peripheral blood CD3+ cells and EBV genome (EBER) in the tumor cells, compared to those without these findings, had significantly higher plasma EBV DNA levels. The majority of circulating EBV DNA molecules was naked form. The plasma EBV DNA levels were not related to survival.
  
  
  CONCLUSIONS
  The concentration of EBV DNA in the plasma was not a prognostic marker in PTCL and PTPD patients.
authors.affiliation: Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat-Yai, Songkhla 90110, Thailand.
authors.forename: Supaporn
authors.initials: S
authors.lastname: Suwiwat
authors.forename: Jintana
authors.initials: J
authors.lastname: Pradutkanchana
authors.forename: Takafumi
authors.initials: T
authors.lastname: Ishida
authors.forename: Winyou
authors.initials: W
authors.lastname: Mitarnun
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017252:CD3 Complex / Q000276:immunology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000097:blood*; D005260:Female; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D017403:In Situ Hybridization / Q000379:methods; D007694:Killer Cells, Natural / Q000473:pathology*; D008213:Lymphocyte Activation; D054391:Lymphoma, Extranodal NK-T-Cell / Q000097:blood / Q000276:immunology / Q000473:pathology / Q000821:virology*; D016411:Lymphoma, T-Cell, Peripheral / Q000097:blood / Q000276:immunology / Q000473:pathology / Q000821:virology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D013601:T-Lymphocytes / Q000473:pathology*
chemical_list: D017252:CD3 Complex; D004279:DNA, Viral