再生基因Ⅳ及其碳水化合物识别域促进裸鼠结直肠癌移植瘤血管的生成

Regenerating gene Ⅳ and its carbohydrate-recognition domain promote angiogenesis of colorectal carcinoma xenografts in nude mice

目的:探讨再生基因Ⅳ(regenerating gene Ⅳ,RegⅣ)及其碳水化合物识别域(carbohydrate-recognition domain,CRD)对裸鼠结直肠癌移植瘤血管生成的影响。方法:将已转染了重组质粒pcDNA3.1-RegⅣ、pcDNA3.1-Reg Ⅳ△ CRD、空载体质粒的人结肠癌LoVo细胞(分别命名为LoVo/RegⅣ、LoVo/Reg Ⅳ△ CRD、LoVo/negative)和自然生长状态的LoVo细胞分别接种于裸鼠皮下。RT-PCR法检测移植瘤组织中RegⅣ及Reg Ⅳ△ CRDmRNA的表达,免疫组织化学法检测移植瘤组织中血管内皮生长因子(vascularendothelial growth factor,VEGF)和CD34的表达,计数移植瘤组织中微血管密度(microvessel density,MVD)。结果:LoVo/RegⅣ移植瘤组织中VEGF的表达水平高于其他3组,差异有统计学意义(P<0.05);LoVo/Reg Ⅳ△ CRD、LoVo和LoVo/negative组间VEGF的表达水平差异无统计学意义(P>0.05);LoVo/RegⅣ移植瘤组织中MVD值明显高于其他3组(P<0.05),LoVo/Reg Ⅳ△ CRD、LoVo和LoVo/negative移植瘤组织间MVD值差异无统计学意义(P>0.05)。结论:RegⅣ基因参与调控结直肠癌的血管生成,其作用与CRD结构域密切相关。

Objective：To investigate the effect of regenerating gene Ⅳ（RegⅣ） and its carbohydrate-recognition domain（CRD）on angiogenesis of colorectal carcinoma xenografts in nude mice.Methods：The LoVo human colorectal carcinoma cells were transfected with recombinant plasmids pcDNA3.1-RegⅣ（LoVo/RegⅣ group）,pcDNA3.1-RegⅣ△CRD（LoVo/RegⅣ△CRD group） or empty vector（LoVo/negative group）,and then the LoVo/RegⅣ,LoVo/RegⅣ△CRD,LoVo/negative and LoVo cells were transplanted subcutaneously in nude mice,respectively.The expression levels of RegⅣ and RegⅣ/△CRD mRNAs in xenograft tissues were detected by RT-PCR.The expression levels of vascular endothelial growth factor（VEGF） and CD34 proteins in xenograft tissues were determined by immunohistochemistry assay.The microvessel density（MVD） in xenograft tissues was calculated.Results：The expression level of VEGF in the xenograft tissues in LoVo/RegⅣ group was higher than those in the other three groups（P0.05）,and there was no difference in VEGF expression among the LoVo/RegⅣ△CRD,LoVo and LoVo/negative groups（P0.05）.The MVD value of xenograft tissues in LoVo/RegⅣgroup was higher than those in the other three groups（P0.05）,and there was no difference among the LoVo/RegⅣ△CRD,LoVo and LoVo/negative groups（P0.05）.Conclusion：RegⅣ participates the angiogenesis of colorectal carcinoma,and this effect may be correlated with its CRD.