Immunohistochemical expression of uPA, uPAR, and PAI-1 in breast carcinoma. Fibroblastic expression has strong associations with tumor pathology

Am J Pathol. 2000 Oct;157(4):1219-27. doi: 10.1016/S0002-9440(10)64637-8.


The urokinase-type plasminogen activator (uPA) system has been implicated in tumor spread. We have used immunohistochemistry to examine three components of this system, ie, uPA, uPA receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1), in a pilot study on 142 cases of breast carcinoma. We wished to determine whether there were any relationships between expression of the proteins in either tumor cells or fibroblasts and clinical and pathological features. Strong uPA expression in each cell type was significantly related to high tumor grade (P = 0.013 and 0.008, respectively), and was more common in invasive than in in situ carcinomas (P < 0.0001). Fibroblastic expression of uPAR was only related to the presence of invasion (P < 0.0001). Strong PAI-1 expression in both cell types was seen in high-grade tumors (tumor cells, P = 0.012; fibroblasts, P < 0.001), but only fibroblastic expression was related to the presence of invasion (P = 0.042). Fibroblastic expression of both uPA and uPAR were positively correlated with tumor size. Although patients with strong fibroblastic expression of uPA showed a tendency toward a shorter time to relapse, none of the plasminogen activator proteins were significantly associated with relapse-free survival. These results suggest that strong expression of uPA, uPAR, and PAI-1 in fibroblasts rather than in tumor cells have the most impact on the clinical behavior of breast cancer. Larger prospective studies are needed to confirm these findings.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Breast / metabolism
  • Breast Diseases / metabolism
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Carcinoma in Situ / metabolism
  • Carcinoma in Situ / pathology
  • Carcinoma, Ductal, Breast / metabolism
  • Carcinoma, Ductal, Breast / pathology
  • Carcinoma, Lobular / metabolism
  • Carcinoma, Lobular / pathology
  • Female
  • Humans
  • Immunohistochemistry / methods
  • Lymph Nodes / pathology
  • Middle Aged
  • Plasminogen Activator Inhibitor 1 / metabolism*
  • Receptors, Cell Surface / metabolism*
  • Receptors, Urokinase Plasminogen Activator
  • Reference Values
  • Staining and Labeling
  • Survival Analysis
  • Urokinase-Type Plasminogen Activator / metabolism*


  • PLAUR protein, human
  • Plasminogen Activator Inhibitor 1
  • Receptors, Cell Surface
  • Receptors, Urokinase Plasminogen Activator
  • Urokinase-Type Plasminogen Activator