Urokinase is an enzyme found mainly in animals and humans. This enzyme regulates the degradation of blood clots in blood vessels. Urokinase is used as a thrombolytic agent in the treatment of heart attacks, pulmonary embolism and other disorders (it is commercially available as Abbokinase) [1]. Urokinase is a member of the family of serine proteases. The main function of urokinase is the conversion of plasminogen into plasmin, which plays a crucial role in the degradation of blood clots [2].

Mature urokinase consists of two polypeptide chains bound together with disulphide bonds. The protein consists of 3 different domains, a protease domain on one chain, and a kringle and EGF-like domain on the other chain. The kringle and EGF-like domains are needed for the interaction of the protein with blood-clotting factors and the release of the protein from the cell, respectively [3][4]. Interestingly, the expression level of urokinase appears to correlate with the process of tumor expansion [5]. The high activity of the urokinase enzyme is considered to lead to degradation of the extracellular matrix and the formation of metastases [6], which suggests that urokinase could be a potential target for cancer therapy [7].


Ivan Konstantinov
Artem Sokolov

Date: Dec 19, 2011


  1. Drug Bank Accession number, DB00013
  2. Uniprot ID, P00749
  3. Patthy L. et al., FEBS Lett. 1984 Jun 4;171(1):131-6.
  4. Nagata K. et al., EMBO J. 1994 Aug 1;13(15):3517-23.
  5. Mazar A.P. et al., Angiogenesis. 1999;3(1):15-32.
  6. Rao J.S., Nat Rev Cancer. 2003 Jul;3(7):489-501.
  7. Gondi C.S. et al., Methods Mol Biol. 2009;487:267-81.