title: Epstein-Barr virus in breast carcinoma in Argentina.
abstract: BACKGROUND
  Because the etiology and progression of breast carcinoma remain unclear, novel mechanisms of disease pathogenesis need to be considered. Recent interest has focused on Epstein-Barr virus (EBV), an oncogenic ubiquitous herpesvirus. Investigations of this association could not only broaden understanding of breast cancer etiology but also have implications regarding early detection, treatment, and prevention.
  
  
  OBJECTIVE
  To assess EBV presence in breast carcinoma in an Argentine series.
  
  
  METHODS
  Breast biopsy specimens of 69 women with breast carcinoma and fresh tumor tissue of 39 of these women were collected. As controls, 17 biopsy specimens of fibroadenomas, 9 of benign epithelial proliferation, 4 of atypical ductal hyperplasia, and 10 of usual ductal hyperplasia and 8 normal breast tissues from women were studied. The EBV-infected cells were identified by means of immunohistochemical analysis, using a monoclonal antibody against Epstein-Barr virus-encoded nuclear antigen 1 (EBNA-1). Polymerase chain reaction (PCR) was used to amplify EBV DNA, with primers that cover the EBV encoded RNA (EBER) and BamHIW regions.
  
  
  RESULTS
  Nuclear expression of EBNA-1 was observed in tumor epithelial cells in 24 (35%) of the 69 cases. We confirmed both positive and negative immunohistochemical results by PCR in those cases where good quality DNA was also available, detecting amplification fragments of 108 base pairs (bp) from the EBER region and 122 bp from the BamHIW region. Neither immunohistochemical analysis nor PCR detected any positive EBV results in the control samples.
  
  
  CONCLUSIONS
  Our results demonstrate the presence and expression of EBV restricted to epithelial tumor cells in a subset of breast carcinomas studied. However, no significant association was observed between EBV expression and worse clinical and pathologic patient characteristics.
authors.affiliation: Virology Laboratory, Ricardo Gutiérrez Children's Hospital, Ciudad de Buenos Aires, Argentina. preciado@conicet.gov.ar
authors.forename: María Victoria
authors.initials: MV
authors.lastname: Preciado
authors.forename: Paola Andrea
authors.initials: PA
authors.lastname: Chabay
authors.forename: Elena Noemí
authors.initials: EN
authors.lastname: De Matteo
authors.forename: Pedro
authors.initials: P
authors.lastname: Gonzalez
authors.forename: Saúl
authors.initials: S
authors.lastname: Grinstein
authors.forename: Andrea
authors.initials: A
authors.lastname: Actis
authors.forename: Hugo Daniel
authors.initials: HD
authors.lastname: Gass
mesh_terms: D000368:Aged; D001118:Argentina; D001943:Breast Neoplasms / Q000821:virology*; D002277:Carcinoma / Q000821:virology*; D020031:Epstein-Barr Virus Infections / Q000150:complications*; D005260:Female; D004854:Herpesvirus 4, Human / Q000302:isolation & purification*; D006801:Humans