摘要目的　探讨星形细胞肿瘤中血管内皮生长因子(VEGF)及诱生型一氧化氮合酶（iNOS）表达与血管生成和恶性程度的关系。方法　采用免疫组织化学和图像分析技术检测61例有随访资料的脑星形细胞肿瘤中VEGF和iNOS的表达水平，并定量检测Ⅷ因子相关抗原(FⅧRAg)以反映内皮细胞数量和微血管密度。结果　星形细胞肿瘤间质血管呈现7种形态特征，血管内皮细胞FⅧRAg阳性细胞总面积和积分吸光度随级别增高而显著增大（P<0.001），且随VEGF标记指数（LI）增高而显著增大（P<0.05）；VEGF LI高的病例组（LI≥25%）患者生存率明显降低。VEGF与iNOS表达水平之间有显著关联性（P<0.001），即随着iNOS表达的减弱，VEGF表达也减弱。结论　FⅧRAg定量检测能较好地反映星形细胞肿瘤血管生成活性；VEGF和iNOS可能通过相互上调表达促进血管生成，它们对于判断星形细胞肿瘤的恶性程度有重要意义。

abstractsObjective　To investigate whether the expression of vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) are asscoiated with angiogenesis and malignancy of astrocytomas. Methods　Immunohistochemistry, semiquantitation and image analysis were used to study the expression features of VEGF and iNOS in 61 cases of astrocytomas having follow-up data. Factor Ⅷ related antigen (FⅧ RAg) was also analysed in reflecting the epithelial cell amount and the microvessel density. Results　Microvessels in astrocytomas could be divided into seven types. The positive reaction areas and IA values of FⅧRAg expression in the endothelium were significantly increased with the increase of tumor grade （P<0.001）and VEGF labeling index (LI) （P<0.05）. The patients with high VEGF LIs （LI≥25%） had a poor prognosis. VEGF expression was significantly related to that of iNOS（P<0.001), i.e., VEGF level was reduced along with the decrease of iNOS reaction. Conclusion　Detection of FⅧRAg could reflect the angiogenesis activities in astrocytomas. VEGF and iNOS could up-regulate each other to promote angiogenesis and are of importance in determining the malignancy degree of astrocytomas.