title: High expression of plasminogen activator inhibitor-2 (PAI-2) is a predictor of improved survival in patients with pancreatic adenocarcinoma.
abstract: OBJECTIVE
  Recent findings suggest that the urokinase-type plasminogen activator (uPA), its receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1), and -2 (PAI-2) play key roles in cancer invasion. The prognostic value of components of this system is well established in breast cancer. However, little is known of its involvement in pancreatic cancer (PC).
  
  
  METHODS
  Quantitative real-time polymerase chain reaction (Q-RT-PCR) was used on tissue-banked specimens and immunohistochemistry (IHC) on paraffin specimens was used to measure expression of uPA, uPAR, PAI-1, and PAI-2 proteins in 46 PC and 12 cystadenoma specimens. Results were related to survival using Cox's proportional hazards testing.
  
  
  RESULTS
  Increased expression of uPA, uPAR, and PAI-1 in PC tissue were independently associated with a higher Union Internationale Contre le Cancer [International Union Against Cancer (UICC)] tumor stage (P < 0.001) and were intercorrelated (P < 0.001). Overexpression of uPAR indicated reduced survival (P = 0.03). Conversely, PAI-2 messenger ribonucleic acid (mRNA) overexpression, which occurred in 21 of 46 tumors, negatively correlated with tumor size (P = 0.008) and survival (P < 0.007) but not with uPA, uPAR, or tumor stage. There was good agreement between PAI-2 mRNA value and IHC score (P < 0.001). Using Cox's stepwise analysis, PAI-2 mRNA value (HR = 0.24; P = 0.001) and UICC tumor stage (HR = 2.014; P = 0.001) independently predicted survival. An IHC score for PAI-2 of 3+ or 4+ also independently predicted improved survival (HR = 2.72; P = 0.025).
  
  
  CONCLUSIONS
  The uPA/uPAR/PAI-1 system is activated in advanced pancreatic cancer and may account for the tumor's aggressive behavior, whereas PAI-2 expression appears to be independent of uPA/uPAR/PAI-1 and is associated with improved prognosis. Because of its intercorrelation with mRNA expression, PAI-2 IHC may be used as an indicator of survival.
authors.affiliation: Department of Surgery, University of Sydney, Royal North Shore Hospital, St. Leonards, NSW, Australia. rsmith@med.usyd.edu.au
authors.forename: Ross
authors.initials: R
authors.lastname: Smith
authors.forename: AiQun
authors.initials: A
authors.lastname: Xue
authors.forename: Anthony
authors.initials: A
authors.lastname: Gill
authors.forename: Christopher
authors.initials: C
authors.lastname: Scarlett
authors.forename: Alexander
authors.initials: A
authors.lastname: Saxby
authors.forename: Adele
authors.initials: A
authors.lastname: Clarkson
authors.forename: Thomas
authors.initials: T
authors.lastname: Hugh
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000601:surgery; D017396:Plasminogen Activator Inhibitor 2 / Q000378:metabolism*; D011379:Prognosis; D016016:Proportional Hazards Models; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; D017396:Plasminogen Activator Inhibitor 2