title: Systematic analysis of human oncogenic viruses in colon cancer revealed EBV latency in lymphoid infiltrates.
abstract: BACKGROUND
  Environmental factors may play a role in colon cancer. In this view, several studies investigated tumor samples for the presence of various viral DNA with conflicting results.
  
  
  RESULTS
  We undertook a systematic DNA analysis of 44 consecutive, prospectively collected primary tumor samples by real time and qualitative PCR for viruses of known or potential oncogenic role in humans, including polyomavirus (JCV, BKV, Merkel cell polyomavirus), HPV, HTLV, HHV-8 and EBV. Negative controls consisted of surgical resection margins. No evidence of genomic DNA fragments from tested virus were detected, except for EBV, which was found in a significant portion of tumors (23/44, 52%). Real-time PCR showed that EBV DNA was present at a highly variable content (median 258 copies in 10(5) cells, range 15-4837). Presence of EBV DNA had a trend to be associated with high lymphocyte infiltration (p = 0.06, χ2 test), and in situ hybridization with EBER1-2 probes revealed latency in a fraction of these lymphoid cells, with just a few scattered plasma cells positive for BZLF-1, an immediate early protein expressed during lytic replication. LMP-1 expression was undetectable by immunohistochemistry.
  
  
  CONCLUSIONS
  These results argue against a significant involvement of the tested oncogenic viruses in established colon cancer.
authors.affiliation: Department of Diagnostic Medicine, Molecular Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Loretta
authors.initials: L
authors.lastname: Fiorina
authors.affiliation: Department of Onco-Hematology, Oncology Section, Fondazione IRCCS Policlinico San Matteo, V.le Camillo Golgi 19, 27100 Pavia, Italy.
authors.forename: Mattia
authors.initials: M
authors.lastname: Ricotti
authors.affiliation: Department of Molecular Medicine, University of Pavia and Anatomic Pathology section, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Vanoli
authors.affiliation: Department of Molecular Medicine, University of Pavia and Anatomic Pathology section, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Ombretta
authors.initials: O
authors.lastname: Luinetti
authors.affiliation: Department of Molecular Medicine, University of Pavia and Anatomic Pathology section, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Dallera
authors.affiliation: Department of Molecular Medicine, University of Pavia and Anatomic Pathology section, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Riboni
authors.affiliation: Department of Diagnostic Medicine, Molecular Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Paolucci
authors.affiliation: Department of Onco-Hematology, Oncology Section, Fondazione IRCCS Policlinico San Matteo, V.le Camillo Golgi 19, 27100 Pavia, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Brugnatelli
authors.affiliation: Department of Molecular Medicine, University of Pavia and Anatomic Pathology section, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Paulli
authors.affiliation: Department of Onco-Hematology, Oncology Section, Fondazione IRCCS Policlinico San Matteo, V.le Camillo Golgi 19, 27100 Pavia, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pedrazzoli
authors.affiliation: Department of Diagnostic Medicine, Molecular Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Fausto
authors.initials: F
authors.lastname: Baldanti
authors.affiliation: Department of Onco-Hematology, Oncology Section, Fondazione IRCCS Policlinico San Matteo, V.le Camillo Golgi 19, 27100 Pavia, Italy.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Perfetti
keywords: Colon cancer; EBV; Oncogenic viruses