PLAU and glioblastoma: For example, in glioblastoma, components of the plasminogen activator (PA) system, such as urokinase-type plasminogen activator (uPA) and its receptor (uPAR), play a critical role in tumor progression and metastasis [196], regulating the proteolytic degradation of the extracellular matrix (ECM) [197], promoting tumor cell invasion, migration, and homing to distant organs [198].