目的研究小剂量长春新碱(Vincristine,VCR)和恩度(Endostar,Endo)联合用药对横纹肌肉瘤(Rhabdomyosarcoma,RMS)BALB/c裸鼠皮下移植瘤的生长抑制作用,并探讨其机制。方法经BALB/c裸鼠右侧腋部皮下注射RMS细胞PLA-802悬液,建立RMS的皮下移植瘤动物模型;接种RMS后第8天,将选模成功的裸鼠随机分为对照组(注射生理盐水)、VCR组、Endo组和联合组,注射部位均为腹腔,注射体积均为0.2 ml/(只.日),每3 d称重1次,并测量肿瘤的长短径,计算肿瘤体积,绘制肿瘤生长曲线,2周后处死裸鼠,称量瘤重,并计算抑瘤率;RT-PCR和Western blot法检测移植瘤细胞中血管内皮生长因子(Vascular endothelial growth factor,VEGF)基因mRNA的转录水平和蛋白的表达水平;免疫组化法检测VEGF和CD31的分布和表达。结果裸鼠接种PLA-802细胞第8天,RMS裸鼠模型复制成功,裸鼠成瘤率为84%(42/50);联合组裸鼠体重和移植瘤的体积、重量均明显小于对照组、VCR组和Endo组(P<0.01);VCR组、Endo组和联合组抑瘤率分别为31.41%、20.75%和48.41%;与对照组相比,VCR组、Endo组和联合组裸鼠移植瘤细胞中VEGF基因mRNA的转录水平和蛋白表达水平均显著下降,且以联合组下降最明显(P<0.05);免疫组化结果显示,联合组VEGF和CD31的表达水平明显低于其他3组。结论小剂量VCR和Endo对RMS的皮下移植瘤的生长具有明显的抑制作用,而联合用药能起到增效作用,其机制可能是通过抑制肿瘤的血管生成而发挥其抑制作用。 Objective To study the inhibitory effect of low dose Vincristine (VCR) and endostar (Endo) on the growth of subcutaneous xenografts in BALB / c nude mice with rhabdomyosarcoma (RMS) and to explore its mechanism. Methods BALB / c nude mice were injected subcutaneously with RMS cells PLA-802 suspension in the axillary region of the BALB / c nude mice to establish a subcutaneous xenograft model of RMS. On the 8th day after inoculating RMS, nude mice were randomly divided into control group Injection of normal saline), VCR group, Endo group and combination group. The injection site was intraperitoneal. The injection volume was 0.2 ml / (day only), and weighed once every 3 days. The tumor growth curve was drawn and the nude mice were sacrificed two weeks later. The tumor weight was measured and the tumor inhibition rate was calculated. The expression of VEGF gene in the tumor cells was detected by RT-PCR and Western blot mRNA transcription levels and protein expression levels; immunohistochemical detection of VEGF and CD31 distribution and expression. Results On the 8th day after inoculation of PLA-802 cells in nude mice, the successful nude mice were successfully replicated in the nude mice model. The tumor formation rate was 84% ​​(42/50) in nude mice. The body weight and the volume and weight of transplanted tumor in nude mice were significantly smaller than those in control group , VCR group and Endo group (P <0.01). The inhibition rates of VCR group, Endo group and combination group were 31.41%, 20.75% and 48.41% respectively. Compared with control group, VCR group, Endo group and combination group The transcript level and protein expression of VEGF gene in the tumor cells were significantly decreased (P <0.05). The expression of VEGF and CD31 in the combined group was significantly lower than that in the other three groups group. Conclusion Low-dose VCR and Endo have significant inhibitory effects on the growth of subcutaneous xenografts of RMS, and the combination therapy can play a synergistic effect, and its mechanism may be through inhibition of tumor angiogenesis and exert its inhibitory effect.