Presence of urokinase-type plasminogen activator receptor in urine of cancer patients and its possible clinical relevance

High levels of urokinase-type plasminogen activator receptor (uPAR) are exp ressed in Various types of cancer. Recent studies showed that cancer patien ts may have increased levels of soluble (s)uPAR in their serum. In the pres ent study, we show that urine samples from healthy volunteers contain measu rable amounts of suPAR. suPAR/creatinine levels from healthy controls showe d only little variation over the day and were even stable during a month of continued monitoring. Importantly, urinary suPAR/creatinine levels were hi ghly correlated with serum suPAR concentrations. Urinary suPAR levels were elevated in patients with different types of cancer. Interestingly, part of the urinary suPAR seemed to be present in a cleaved form, as has been foun d in tumor tissue extracts. Together with the recently established, cell mi gration-promoting effect of certain cleaved fragments of suPAR, the present data suggest that the measurement of urinary suPAR and/or its cleaved form s might have clinical implications.