Activator catalyzes the conversion of plasminogen to plasmin, which can degrade a large amount of tissue protein and convert inactive collagenogen into active collagenase, thus degrading collagen matrix. It has been found that high levels of urokinase type PA (uPA) are closely related to the invasion process of tumors; The malignant development of a variety of tumor tissues is accompanied by changes in the amount of uPA inhibitor type 1 (PAI1) and type 2 (PAI2).
Action conditions
Malignant tumor The ability to invade adjacent normal tissues involves tumor cell The PAs secreted by tumor cells provide a key cellular and molecular mechanism of action in the process of growth and spread to the destruction of the surrounding normal tissue barrier. UPA can bind to specific Cell surface receptor To activate plasminogen into plasmin, and cause tissue degradation and cell migration It plays an important role in the process of tumor invasion and metastasis. In this study Glioma With the increase of grade, the malignant degree of tumor increases, and the expression level of uPA increases significantly, while there is no expression of uPA in normal brain tissue, indicating that the role of uPA in the occurrence and evolution of glioma may be realized by increasing the invasiveness of tumor cells. 
Common patterns of transcriptional initiation regulation (a and b: negative regulation, c and d: positive regulation) [1]
