VEGFR-3小干扰RNA对结肠癌裸鼠移植瘤生长的影响

目的:研究血管内皮生长因子受体3(vascularendothelial growth factor receptor 3,VEGFR-3)小干扰RNA对结肠癌细胞移植瘤模型生长的影响.方法:构建VEGFR-3小干扰RNA表达载体.将结肠癌LoVo细胞注射入裸鼠皮下建造裸鼠移植瘤模型.将15只裸鼠结肠癌模型随机分成3组:实验组(pG-siRNA/VEGFR-3重组质粒)、阴性对照组(pG-HK重组质粒)与空白对照组.分别瘤体内注射相应的siRNA混合物或转染剂混合液,每3 d注射1次,共注射3次,观察肿瘤体积的变化;6 wk后处死裸鼠,肿瘤称取质量,并进行qRT-PCR和Western blot测定VEGFR-3 mRNA和蛋白的变化,通过免疫组织化学进行微淋巴管计数.结果:实验组移植瘤体积和质量明显小于阴性对照组和空白对照组,有显著的统计学意义(P<0.001).实验组抑制率为52.75%,与对照组相比,差异有显著(P<0.001).qRT-PCR和Western blot测定VEGFR-3 mRNA和蛋白的变化比较,实验组有明显降低(P<0.001).实验组淋巴管计数较对照组差异显著(P<0.05).结论:VEGFR-3 siRNA可以抑制裸鼠结肠癌细胞移植瘤的生长,并减少裸鼠移植瘤淋巴管生成,能有效抑制结肠癌细胞的生长.

SiRNA-mediated down-regulation of vascular endothelial growth factor receptor 3 inhibits the growth of human colorectal cancer cell xenografts in nude mice

AIM: To investigate the inhibory effect of siRNA-mediated down-regulation of vascular endothelial growth factor receptor 3(VEGFR-3) on the growth of human colorectal carcinoma cell xenografts in nude mice.METHODS: Human colorectal carcinoma LoVo cells were transplanted subcutaneously into Balb/c nude mice to establish a xenograft tumor model.Fifteen model mice were randomized into three groups and were injected with recombinant plasmid carrying the siRNA(pG-siRNA/VEGFR-3),empty plasmid(pG-HK),and tranfection reagent(control),respectively.Tumor volume and weight were measured,and the reduced rate of tumor growth was calculated.VEGFR-3 mRNA and protein expression was detected by qRT-PCR and Western blot.Microlyphamatic vessels were counted by immunohistochemistry.RESULTS: Tumor volume and weight were significantly less in the pG-siRNA/VEGFR-3 group than in the pG-HK and control group(both P < 0.001).Compared to the control group,the reduced rate of tumor growth was 52.75%,and VEGFR-3 expression was down-regulated in the pG-siRNA/VEGFR-3 group.However,there was no similar inhibitory effect in the control group and pG-HK group.Significant differences in microlymphatic counts were noted between the pG-siRNA/VEGFR-3 group and the two control groups(both P < 0.05).CONCLUSION: SiRNA-mediated down-regulation of VEGFR-3 could inhibit the growth of human colorectal cancer cell xenografts in nude mice and reduce lymphangiogenesis.