Effects of VEGF Expression on Angiogenesis,Tumor Growth and Metastasis in Osteosarcoma

Objective:To investigate the role of vascular endothelial growth factor(VEGF)on angiogenesis,tumor growth and metastasis in osteosarcoma,and its clinical significance.Methods:Sixty-nine specimens of primary osteosarcomas were studied with immunohistochemistry and in situ hybridization techniques.The correlation between the expression of VEGF and the density of CD34-positive microvessels,the prognostic significance of VEGF expression,microvessel density(MVD)and clinicopathological variables were evaluated.Results:VEGF staining was positive in 39 tumors(56.5%)in which the CD34-positive microvessels was significantly higher than that in VEGF-negative 30 tumors ( P 0.05),and multivariate analysis indicated that microvessel density(MVD)and VEGF expression were closely correlated with patients' poor prognosis as well as metastasis.In terms of clinicopathological variables,the microscopic surgical margin appearance,Enneking stage,tumor size and patient's age were correlated with the patient's prognosis( P 0.05),particularly,the microscopic surgical margin appearance had more prognostic significance especially in predicting metastasis and local relapse.There was no correlation between patient's prognosis and patient's gender,surgical definition and histologic type.Conclusions:VEGF is a critical angiogenic stimuli which stimulates angiogenesis,tumor growth and metastasis in osteosarcoma,the microvessel density(MVD)and VEGF expression can function as two independent prognostic variables in osteosarcoma.