Effect of inhibiting MMP-2, MMP-9, uPA, and tPA on glioma cell migration. (A) Track graphs showing effects of MMP-2, MMP-9, uPA, and tPA inhibitors on U87 cell migration. Each graph axis represents 200 µm. Inhibitors of MMP-2 (ARP 100, 100 µM) and MMP-9 (CAS 1177749-58-4, 25 µM) significantly decreased U87 cell migration on cell culture dish or in collagen hydrogels. Aprotinin (40 µg/ml) and tranexamic acid (3 mM) inhibited U87 migration in collagen hydrogel but not on cell culture dish. (B) and (C) Quantification of tumor cell migration after U87 and A172 glioma cells treated with inhibitors respectively. *p < 0.05, compared with tumor cell migration of corresponding group without inhibitor treatment. (D) and (E) Quantification of tumor cell migration distance after U87 and A172 glioma cells treated with inhibitors, respectively. *p < 0.05, compared with tumor cell migration of corresponding group without inhibitor treatment.