Re: Urokinase and Urokinase Receptor: Association With In Vitro Invasiveness of Human Bladder Cancer Cell Lines

Extract

Urokinase-type plasminogen activator (uPA) is a serine protease causally involved in cancer invasion and metastasis [reviewed in ( 1 , 2 )]. It is now generally believed that uPA mediates metastasis by attaching to a membranebound receptor termed uPAR ( 1 , 2 ). Consistent with their role in experimental metastasis, high levels of these molecules have been found to associate with poor prognosis in a variety of human cancers ( 2 , 3 ). In a recent report, Hudson and McReynolds ( 4 ) concluded that both uPA and its receptor were necessary for in vitro invasion by bladder tumor cells. In an accompanying editorial, Hasui and Osada ( 5 ) stated that further work was necessary to establish the relative prognostic strengths of uPA and uPAR in different human cancers.