title: Co-expression of urokinase with haptoglobin in human carcinomas.
abstract: BACKGROUND
  We have shown that colon and breast cancer contains large amounts of urokinase (uPA), and that these cells are the actual sites of its synthesis. We isolated a large complex molecule consisting of the beta-chain of uPA, both chains of haptoglobin (Hp), and part or all of an NCAM-like molecule. The question arose whether it would be possible to show the presence of Hp in the same cells where uPA was found.
  
  
  METHODS
  Human colon and breast adenocarcinomas were investigated for expression of Hp and uPA by immunohistochemistry. Fluorescence in situ hybridization was used to identify the cells of origin of these antigens.
  
  
  RESULTS
  Hp was expressed in 8 of 11 colon adenocarcinomas, and in 10 of 12 breast tumors. uPA was demonstrable on the cell membrane and in the cytoplasm of all 11 colon adenocarcinomas studied, and cytoplasmic uPA-mRNA was found in all cases. While uPA was also detected in some stromal and inflammatory cells, Hp was present abundantly in such cells, as well as in capillary endothelial cells. Hp-mRNA was also found in both colon and breast tumors wherever the antigens were expressed.
  
  
  CONCLUSIONS
  uPA and Hp are produced by the cancer cells and are not taken up by stromal elements. While the role of uPA in the malignant process is well documented, that of Hp is largely unexplored. Its ubiquity, shown here, suggests that it is also involved in some aspects of that process.
authors.affiliation: Department of Pathology, Roswell Park Cancer Institute and State University of New York at Buffalo, Buffalo, New York 14263, USA.
authors.forename: Shashikumar
authors.initials: S
authors.lastname: Harvey
authors.forename: Shin
authors.initials: S
authors.lastname: Kohga
authors.forename: Sheila N J
authors.initials: SN
authors.lastname: Sait
authors.forename: Gabor
authors.initials: G
authors.lastname: Markus
authors.forename: Thelma C
authors.initials: TC
authors.lastname: Hurd
authors.forename: Maisie
authors.initials: M
authors.lastname: Martinick
authors.forename: Joseph
authors.initials: J
authors.lastname: Geradts
authors.forename: Rakhee
authors.initials: R
authors.lastname: Saxena
authors.forename: John F
authors.initials: JF
authors.lastname: Gibbs
mesh_terms: D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D003110:Colonic Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D005260:Female; D006242:Haptoglobins / Q000235:genetics*; D006801:Humans; D017403:In Situ Hybridization; D017404:In Situ Hybridization, Fluorescence; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D012811:Sigmoid Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology / Q000601:surgery; D014568:Urokinase-Type Plasminogen Activator / Q000235:genetics*
chemical_list: D006242:Haptoglobins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D014568:Urokinase-Type Plasminogen Activator