SERPINE1 and neoplasm: Although the canonical view is that PAI-1 functions as an inhibitor of uPA and tPA to maintain clot formation, several reports have revealed that the urokinase plasminogen activator system, regulated by uPA, uPAR, and PAI-1, mediates proteolytic activity and the degradation of the basement membrane and extracellular matrix (ECM), which leads to tumor invasion and metastasis [3, 4].