title: DKK-1 in prostate cancer diagnosis and follow up.
abstract: BACKGROUND
  Dickoppf-1 (DKK-1) is a negative regulator of bone formation with tumorigenic potential. The up-regulation of DKK-1 is an early event in prostate cancer (PCa) development, thus we investigated its role as a marker in the diagnosis and prognosis of PCa.
  
  
  METHODS
  We retrospectively enrolled 159 patients who underwent prostate biopsy, either for elevated PSA or suspect digital rectal examination, between 2003 and 2010. During the biopsy, one serum sample was collected from all patients; PSA and DKK-1 were measured by ELISA technique. Amongst the biopsy of 159 patients 75 were affected by PCa and 84 were not the mean period of follow-up for these patients was 5 years; a new biopsy was performed in case of PCa suspicion.
  
  
  RESULTS
  PSA performed better than DKK-1 in detecting PCa (0.63 vs 0.51 respectively). Differently from PSA DKK-1 was significantly higher in patients who developed PCa during follow-up than in cancer-free ones, thus DKK-1 performed better than PSA in detecting these patients (0.67 vs 0.55). DKK-1 was significantly lower in patients with bone metastases, whereas PSA was not significantly different in patients with different outcomes.
  
  
  CONCLUSIONS
  DKK-1 might be predictive for patients negative at first biopsy who will develop PCa and in the prognosis of bone metastases. It performed worse than PSA in the early diagnosis of Pca.
authors.affiliation: Gerontology Section, Department of Medical Sciences, University of Torino, Corso Bramante 88/90, 10126 Torino, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: D'Amelio
authors.affiliation: Center for Research in Experimental Medicine (CeRMS), Hospital City of Health and Science of Turin, Turin, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Roato
authors.affiliation: Urology Section, Department of Surgical Science, Hospital City of Health and Science of Turin, University of Turin, Turin, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Oderda
authors.affiliation: Urology Section, Department of Surgical Science, Hospital City of Health and Science of Turin, University of Turin, Turin, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Soria
authors.affiliation: Urology Section, Department of Surgical Science, Hospital City of Health and Science of Turin, University of Turin, Turin, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Zitella
authors.affiliation: Department of Orthopedics, Hospital City of Health and Science of Turin, Turin, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Ferracini
authors.affiliation: Baldi & Riberi Lab, Hospital City of Health and Science of Turin, Turin, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Mengozzi
authors.affiliation: Urology Section, Department of Surgical Science, Hospital City of Health and Science of Turin, University of Turin, Turin, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Gontero
authors.affiliation: Gerontology Section, Department of Medical Sciences, University of Torino, Corso Bramante 88/90, 10126 Torino, Italy.
authors.forename: Giovanni Carlo
authors.initials: GC
authors.lastname: Isaia