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Updated: Aug 13, 2026

Monitoring Functionality and Morphology of Vasculature Recruited by Factors Secreted by Fast-growing Tumor-generating Cells
09:03

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Published on: November 23, 2014

Plasminogen activator inhibitor-1 in tumor growth, angiogenesis and vascular remodeling

Steingrimur Stefansson1, Grainne A McMahon, Eric Petitclerc

  • 1Vascular Biology Department, Jerome H. Holland Laboratory for the Biomedical Sciences, American Red Cross, 15601 Crabbs Branch Way, Rockville, MD 20855, USA.

Current Pharmaceutical Design
|July 23, 2003
PubMed

Plasminogen activator inhibitor-1 (PAI-1) is the principal inhibitor of urokinase type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA), and as such is thought to play an important role in the regulation of extracellular matrix remodeling. In blood, PAI-1 is bound to the adhesion protein vitronectin and is associated with vitronectin in fibrin clots and the provisional matrix. Elevated levels of PAI-1 are associated with atherosclerosis and an increased thrombotic tendency, while PAI-1 deficiency leads to increased fibrinolysis and bleeding. PAI-1 is also elevated in many solid tumors and is associated with a poor prognosis in cancer. PAI-1 has been shown to be a potent regulator of both vascular cell migration in vitro and of angiogenesis and tumor growth in vivo. PAI-1 can both promote and inhibit tumor growth and angiogenesis. Low concentrations of PAI-1 can stimulate tumor angiogenesis while treatment of animals with high doses of PAI-1 inhibits angiogenesis and tumor growth. Hence, PAI-1 appears to have a multifunctional role in regulating the migratory and fibrinolytic activity of vascular cells, and this, in turn, may help to explain the many varied actions of PAI-1.

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