Abstract: AIM: To study the role of Yiqiyangying Fang on angiogenesis and vascular endothelial growth factor (VEGF) in tumor cells transplanted on chick chorioallantoic membrane(CAM). METHODS: The chicken CAM model with tumor cells transplanted was adopted.The drug-contained serum was prepared using serum pharmacological method.The effect of CAM angiogenesis induced by tumor cells was observed in serum containing drugs and normal sodium serum as control group.The expression of VEGF in tumor cells transplanted on CAM was investigated by immunohistochemical analytics methods. RESULTS: The rat blood serum containing Yiqiyangying Fang inhibited angiogenesis in chicken CAM induced by tumor cells transplanted.The expression of VEGF in Yiqiyangying Fang group was lower than that in control group, there was statistical difference (P<0.05). CONCLUSION: Yiqiyangying Fang has significant inhibitory effects on angiogenesis induced by tumor cells in CAM.The down-regulation of VEGF expressions may be one of its mechanisms for inhibiting tumor angiogenesis.

Key words: Yiqiyangyin Fang, vascular endothelial growth factor, angiogenesis