title: Validation of the diagnostic and prognostic relevance of serum MMP-7 levels in renal cell cancer by using a novel automated fluorescent immunoassay method.
abstract: OBJECTIVE
  Despite encouraging results in other cancers, in renal cell cancer, no consensus exists regarding the diagnostic and prognostic relevance of MMP-7. The aim of this study was to assess the diagnostic and prognostic potential of serum MMP-7 levels in renal cell cancer. Furthermore, parallel to the widely used ELISA method, we tested a new, fluid-phase, fluorescent immunoassay (B.R.A.H.M.S KRYPTOR®) for the quantitation of MMP-7.
  
  
  METHODS
  We analyzed the serum samples of 174 individuals (77 patients and 97 age-matched healthy controls) by a commercially available sandwich ELISA and by a novel, automated, fluid-phase immunofluorescent assay (B.R.A.H.M.S KRYPTOR®). Results were correlated with the clinicopathological and follow-up data.
  
  
  RESULTS
  MMP-7 concentrations showed a high concordance level (R (2) = 0.979) between the two methods (p < 0.001). Serum MMP-7 concentrations were significantly higher in patients compared to controls. At a cutoff value of 3.15 ng/ml, a specificity and a sensitivity of 70 and 82 % for the detection of RCC was found. Patients with metastasis had significantly higher MMP-7 levels as those without metastasis (p = 0.038 by KRYPTOR, p = 0.011 by ELISA). High MMP-7 levels proved to be independently associated with shorter overall, disease-specific and metastasis-free survival, regardless of the analytical method.
  
  
  CONCLUSIONS
  Based on these results, serum MMP-7 levels have both diagnostic and prognostic potential. The KRYPTOR method provided comparable results to the standard ELISA analysis, with a high concordance level and can therefore be considered as a surrogate method. Its flexibility and automated operation make the KRYPTOR MMP-7 assay suitable for routine laboratory use in the daily practice.
authors.affiliation: Department of Urology, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147, Essen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Niedworok
authors.affiliation: Department of Urology, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147, Essen, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: vom Dorp
authors.affiliation: Department of Urology, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147, Essen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Tschirdewahn
authors.affiliation: Department of Urology, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147, Essen, Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Rübben
authors.affiliation: Institute of Pathology, University Hospital of Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Henning
authors.initials: H
authors.lastname: Reis
authors.affiliation: Department of Urology, Semmelweis University, Budapest, Hungary.
authors.forename: Miklos
authors.initials: M
authors.lastname: Szucs
authors.affiliation: Department of Urology, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147, Essen, Germany. sztibusz@gmail.com.|Department of Urology, Semmelweis University, Budapest, Hungary. sztibusz@gmail.com.
authors.forename: Tibor
authors.initials: T
authors.lastname: Szarvas
mesh_terms: D000368:Aged; D001331:Automation; D014408:Biomarkers, Tumor / Q000097:blood; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000201:enzymology*; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005455:Fluorescent Antibody Technique / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis / Q000201:enzymology*; D008297:Male; D020783:Matrix Metalloproteinase 7 / Q000097:blood*; D011379:Prognosis; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D014408:Biomarkers, Tumor; D020783:Matrix Metalloproteinase 7
keywords: KRYPTOR; MMP-7; Metastasis; Prognosis; Renal cell cancer