[A plasminogen regulation system in brain tumors]

Area of Science:

• Neuro-oncology
• Molecular Biology
• Biochemistry

Background:

• Malignant tumor progression and neovascularization are linked to plasminogen activators and PAI-1 inhibitor.
• The specific roles of these factors in diverse brain tumors remain under-investigated.

Purpose of the Study:

• To comparatively analyze plasminogen activator and PAI-1 inhibitor regulation in glioblastomas, breast cancer metastases, and meningiomas.
• To examine these factors in perifocal tissues surrounding brain tumors.

Main Methods:

• Enzyme-linked immunosorbent assay (ELISA) was used to measure urokinase (uPA), tissue plasminogen activator (tPA), and PAI-1 inhibitor levels.
• Tumor and perifocal tissues from 56 patients with breast cancer metastases, glioblastomas, and meningiomas were analyzed.
• Histological confirmation was performed for all samples.

Main Results:

• Glioblastomas and breast cancer metastases showed significantly different uPA, tPA, and PAI-1 levels compared to normal tissue surrounding meningiomas.
• Malignant tumors exhibited elevated uPA and PAI-1 levels, with PAI-1 predominant in tumor tissue.
• tPA levels were reduced in most tissues, except glioblastoma, suggesting a protective role in meningiomas and suppressed activation in malignant tumors.

Conclusions:

• uPA and PAI-1 are directly implicated in the metabolism of malignant gliomas and breast cancer brain metastases.
• tPA plays a protective role in meningiomas, while its activation is inhibited in malignant brain tumors.