uPAR depletion or blocking impairs migration of uPAR-expressing cells.

<p><b>A:</b> Prostate carcinoma (PC3) cells were transfected with a uPAR-targeting siRNA or a non-targeting control siRNA; then, cells were partly lysed for Western blot analysis with a uPAR-specific antibody (left) and partly loaded in Boyden chamber and allowed to migrate toward 10% FBS. Migrated cells were fixed, stained with hematoxylin, and counted (middle panel). The values are the mean±SD of a representative experiment performed in triplicate. Results of the migration assay are also expressed as percentage of cells migrated towards serum over the cells migrated without serum; 100% values represent cell migration in the absence of chemoattractant (right). (*) p≤0.05, as determined by the Student's <i>t</i> test. <b>B:</b> PC3 cells were pre-incubated with nonimmune immunoglobulins (Ig) or anti-uPAR polyclonal antibodies, plated in Boyden chambers and allowed to migrate toward 10% FBS. Migrated cells were fixed, stained with hematoxylin, and counted (left). Results of the migration assay are also expressed as percentage of cells migrated towards serum over the cells migrated without serum; 100% values represent cell migration in the absence of chemoattractant (right). The values are the mean±SD of three experiments. (*) p≤0.05, as determined by the Student's <i>t</i> test.