人脑胶质瘤病理分级与Ⅰ型纤溶酶原激活物抑制物关系的研究

Study on the relationship between type-1 plasminogen activator inhibitor and malignant phenotype of human gliomas

目的观察I型纤溶酶原激活物抑制物（PAI－1）在人脑胶质瘤中的表达特征，研究其与胶质瘤病理分级的关系及其对胶质瘤恶性生长的调控作用，方法用抗PAI－1单克隆抗体对57例不同恶性程度的星形细胞瘤、13例良性脑膜瘤和10例正常脑组织进行免疫组织化学染色和半定量分析。结果胶质瘤恶性程度越高，PAI－1的表达程度越高。良性脑膜瘤与低度恶性胶质瘤表达程度均较低，正常脑组织未见表达、PAI－1的阳性染色主要集中于血管，坏死灶周围的PAI－1阳性血管更为集中，结论PAI－1在对抗肿瘤尿激酶所引起的肿瘤血管组织和肿瘤基质的自身降解及胶质瘤新生血管形成起重要作用。在肿瘤坏死灶周围PAI－1表达增强可能是机体防止肿瘤无限制迅速生长的防御机制．

To study the patterns of the expression of Type-1 plasminogen activator inhibitor (PAI-1) in human gliomas and its role in malignant phenotype of gliomas. Methods The immunohistochemical localizahon of PAI-1 was evaluated by using the avidin-biotin immunoperoxidase technique in 80 surgically excised specimens. The immunohistochemical staining results were densitometrically semiquantitatived. Results The expression intensity of the PAI -1 correlated positively with biological malignancy of astrocytoma. and it was undetectable in normal brain tissue. The staining for PAI-1 was mainly localized in blood vessels, especially the glomeruloid-shaped proliferative vessels. The positive staining for PAI-1 within the astrocytoma cells perse was not uncommon. it was also observed on some of macrophages and neurons. ConcluSions It was shown that over expression of PAI-1 was a constant feature of invasive malignant astrocytomas in vino. The cellular source of PAI-1 was not only from endothelial cells and astrocytoma cells, but also from some other cells, including normal neurons and macrophages. PAI-1, the main inhibitor of plas minogen activators. may play an important role in angiogenesis and in protection of tumor stroma from autodegradation by tumor cell plasminogen activators.