Expression Of Vascular Endothelial Growth Factor And Matrix Metalloproteinases-9 In Meningiomas

Objective According to the patho-classification criteria of WHO (1999) , three kinds of meningiomas including atypical type , papilla type ,and malignant meningioma are malignant among all 15 types and 3 grades . They have much stronger invasion power and the more development of malignant degree ,the more invasion power and recurrence possibility. VEGF can enhance Vascular proliferation and infiltrate brain tissues . MMPs might play important roles in meningiomas'angiogenesis and proliferation by ECM degradation, while TIMP ,its specific inhibitor , can inhibit tumor invasion and metastasis in meningiomas. In this study , we investigate the relation between VEGF, MMP-9 and TIMP-1 exprssion and invasion of meningiomas.Methods Forty-five patients with primary meningiomas, operatedon in the Department of Neurosurgery at the Union Hospital from Jan. 1993 to June 2000 , were selected randomly from the Department of Pathology files. Among them , 13 cases were proved by operation to be have alreadly invased periphery brain tissues The S-P immunohistochemical staining method was used to examine the expression of VEGF, MMP-9 and TIMP-1 in 45 cases of different histological types of meningioma . The positive cells were stained to be brown-yellow , mainly on cell membrane and in cyto-plasm. Cell counting was performed at high power (400×) and a minimum of 1000 total cells were counted per slide. The total positived number of cells counted, which was then expressed as a percentage.Results The VEGF,MMP-9 and TIMP-1 positivity rates were 40%, 36%, 52% in the benign meningiomas respectively , and 70%,75%,55% in malignant meningiomas respectively . There was significant difference in express of VEGF among the different histological types of human meningiomas . (X2=15.53,P=0.0004).There was also significant difference among the different in express of MMP-9 histological types of human meningiomas . While there was no significant difference in express of TIMP-1 among the different histological types of human meningiomas . Among their relations analysed by Spesrmam rank test ,there were only correlated between the express of VEGF and the expression of MMP-9. Chi-square test and Spesrmam rank test were used to the attained data by spss 11.5 software.Conclusions Malignant meningiomas have a significantly higher VEGF and MMP-9 positivity rate when compared with benign meningiomas and there were significant differences among the 2 types , especially in histological type of malignant .VEGF and MMP-9 were relative to the biological speciality of meningiomas and coordinated accelerate the invasion of the meningiomas. The imbalance of MMP-9/TIMP-1 is relative to the degree of malignancy and invasion of meningiomas. There was relation between expression of MMP-9 and malignant characteristics of meningiomas and no link between expression of MMP-9 and malignant characteristics of meningiomas. MMP-9 and TIMP-1 have different mechanism in tumor invasion and metastasis in meningiomas and there are no relation among them.