Tissue type plasminogen activator, but not urokinase, exerts transformation-enhancing activity

Int J Cancer. 1984 May 15;33(5):563-7. doi: 10.1002/ijc.2910330503.


Previous studies have established that plasma cryoprecipitates of tumor patients, culture media of transformed cells and defined proteolytic fragments of fibronectin enhance the morphological cell transformation ( TEF activity) in cultures of chicken embryo fibroblasts infected with temperature-sensitive mutants of Rous sarcoma virus. We now report that purified human tissue type plasminogen activator (t-PA), but not urokinase (u-PA), has a similar TEF activity, at doses as low as 2 ng/ml (30 pM). Specific antibodies effectively neutralized the activity. No significant contamination (less than or equal to 1%) between the preparations of t-PA and fibronectin (FN) or its fragments ( FNdp ) was detected. The results suggest that t-PA may have a direct role in the process of morphological cell transformation in vitro.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Transformation, Neoplastic / drug effects*
  • Fibronectins / analysis
  • Humans
  • Plasminogen Activators / analysis
  • Plasminogen Activators / pharmacology*
  • Urokinase-Type Plasminogen Activator / pharmacology*


  • Fibronectins
  • Plasminogen Activators
  • Urokinase-Type Plasminogen Activator