We have shown that uPA and uPAR downregulation inhibits invasion in SNB19 glioma cells by decreasing phosphorylation of the Ras-activated FAK, p38MAPK, JNK and ERK1/2, as well as the MEK-activated phosphatidylinositol 3-kinase, AKT and mTOR pathway, indicative of a feedback signaling mechanism of the uPAR/uPA system [10]. Here, PLAU is linked to central nervous system cancer.