纤溶酶原激活抑制因子1基因在人脑星形细胞瘤中的表达及意义

EXPRESSION AND ITS SIGNIFICANCE OF PLASMINOGEN ACTIVATOR INHIBITOR1 GENE IN HUMAN ASTROCYTOMA

采用Ｎｏｒｔｈｅｒｎｂｌｏｔ分子杂交和ＡＢＣ免疫组化方法检测３６例人脑星形细胞瘤纤溶酶原激活抑制因１（ＰＡＩ－１）基因ｍＲＮＡ和蛋白表达。所有星形细胞瘤组织均可表达３．０ｋｂ和２．２ｋｂ的ＰＡＩ－１ｍＲＮＡ转录物；高级别星形细胞瘤ＰＡＩ－１ｍＲＮＡ表达水平显著高于低级别星形细胞瘤（Ｐ＜０．０１）；ＰＡＩ－１ｍＲＮＡ表达水平与星形细胞瘤的坏死（ｒ＝０．５１，Ｐ＜０．０１）、微血管数量（ｒ＝０．３３，Ｐ＜０．０１）及脑水肿（ｒ＝０．２７，Ｐ＜０．０１）呈正相关。ＰＡＩ－１蛋白主要分布在高级别星形细胞瘤的瘤细胞和内皮细胞，尤以血管增殖部位和坏死灶周围较为显著，低级别星形细胞瘤呈低表达。结果提示ＰＡＩ－１基因与人脑星形细胞瘤的级别、坏死、血管生成及脑水肿密切相关，其高表达可作为恶性星形细胞瘤表型诊断之一。

The mRNA and protein expression of plasminogen activator inhibitor1 (PAI1) gene were examined with Northern blot hybridization and ABC immunohistochemical method in 36 cases of human astrocytomas. All tissues of astrocytomas expressed 3.0kb and 2.2kb transcripts of PAI1 mRNA. The PAI1 mRNA level in highgrade astrocytomas was considerably higher than those in lowgrade astrocytomas (P<0.01). PAI1 mRNA expression was positively correlated with necrosis (r=0.51, P<0.01), microvessel quantity (r=0.33,P<0.01) and brain edema (r=0.27, P<0.01), respectively. The distribution of PAI1 protein was mainly in tumor cells of highgrade astrocytomas, particularly abundant in areas of vascular proliferation and in tumor cells surrounding necrotic foci, whereas it was only weekly expressed in lowgrade astrocytomas. The results indicated that the expression of PAI1 gene was closely related with the grade, necrosis, angiogenesis of astrocytoma and brain edema, and its high expression may be used as one of the diagnosti