High Serum Level of Plasminogen Activator Inhibitor-1 Predicts Histological Grade of Intracerebral Gliomas

Background: No serum marker is currently available for the diagnosis and treatment of gliomas. Plasminogen activator inhibitor-1 (PAI-1) controls the proteolytic activity in cancer cells and cellular migration during angiogenesis. Patients and Methods: To verify the potential of PAI-1 as a serum marker for gliomas, the serum PAI-1 concentrations were measured by ELISA in 57 glioma patients and 34 healthy volunteers. Results: We found significantly higher serum levels in the patients with high-grade gliomas than in the healthy volunteers (p=0.0009, unpaired t-test) and those with low-grade tumors (p=0.0074). Furthermore, high-grade glioma patients with a low serum level of PAI-1 survived significantly longer than those with high levels (p=0.0082). Immunohistochemical analysis using anti-PAI-1 antibody revealed dense and spotty staining in the high-grade tumor tissues from the patients with high serum PAI-1 levels. Conclusion: These results suggest that the serum PAI-1 level can be a marker for the prediction of histological grade in intracerebral glioma.