title: Diagnostic and prognostic role of matrix metalloproteases in cancer.
abstract: BACKGROUND
  Matrix metalloproteases (MMPs) are key players in the progression and metastasis of cancer. MMPs cleave extracellular matrix components and in this way promote tumor growth, invasion and vascularization. MMPs also affect tumor progression by regulating availability and activity of growth factors, inflammatory cytokines and chemokines. Accordingly, several MMPs have been found to serve as prognostic indicators in solid tumors. Usually the increased levels of MMPs in patients' tumor tissue or serum/plasma are associated with poor outcome. Interestingly, recent results show that certain MMPs also serve as tumor suppressors.
  
  
  OBJECTIVE
  This review discusses the latest view on MMPs as diagnostic and prognostic indicators in cancer patients.
  
  
  METHODS
  Studies with clinical samples of 70 or more patients are included in particular. In addition, the possible roles of MMPs in future molecular diagnostics and in the evaluation of therapeutic responses are discussed.
  
  
  CONCLUSIONS
  MMP-9 in particular has shown prognostic value in various types of tumor, and its measurement in circulation, urine or tumor tissue might help in clinical surveillance of otherwise problematic patient cases. There is upcoming new knowledge on MMPs in therapy response evaluation, in which MMPs might be useful together with CT scans and other clinically more established prognostic factors. Certain MMPs have a dual role in terms of cancer-modulating properties and thus it is essential to evaluate their expression and function in tumor cells and host environment to select validated therapy targets but spare MMP antitargets.
authors.affiliation: Turku University Hospital, Department of Oncology and Radiotherapy, POB 52, FIN-20521 Turku, Finland +358 2 313 0804 ; +358 2 313 2809 ; pia.vihinen@tyks.fi.
authors.forename: Pia
authors.initials: P
authors.lastname: Vihinen
authors.forename: Risto
authors.initials: R
authors.lastname: Ala-Aho
authors.forename: Veli-Matti
authors.initials: VM
authors.lastname: Kähäri