铜对H22荷瘤小鼠肿瘤生长及肝功能和免疫功能的影响

EFFECT OF COPPER ON TUMOR GROWTH,LIVER FUNCTION,AND IMMUNE SYSTEM IN H22 TUMOR-BEARING MICE

目的通过建立H22荷瘤小鼠模型,探讨适宜的铜浓度对小鼠肿瘤生长及肝功能和免疫功能的影响。方法选取SPF级昆明种小鼠80只,随机分为灌胃给水组(A组),灌胃给水+四硫钼酸铵盐(TM)组(B组),分别灌胃给予0.06、0.30、1.50mg/kg硫酸铜组(C、D、E组),分别灌胃给予0.06、0.30、1.50 mg/kg硫酸铜+1mg/kg TM组(F、G、H组)。按照分组用硫酸铜溶液给小鼠灌胃4周后,将H22腹水瘤细胞接种于小鼠右腿部,建立H22荷瘤小鼠模型。再根据相应的分组及所给予的硫酸铜浓度继续灌胃4周。8周后,处死小鼠。采用ICP-MS检测小鼠血清中铜的浓度;采用全自动生化分析仪检测小鼠血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)和白蛋白(ALB)的水平;采用实时定量PCR方法检测肿瘤组织中血管内皮生长因子(VEGF)和碱性成纤维细胞生长因子(bFGF)mRNA的表达。结果与A、F、G、H组相比,D、E组肿瘤均有不同程度的增长,差异有显著性(F=9.034,P<0.05)。各组小鼠的肝功能指标AST、ALT和ALB以及脾脏指数和胸腺指数比较差异无显著性(P>0.05)。ICP-MS检测结果显示,各组小鼠血清铜水平比较差异有显著性(F=3.803,P<0.05);且血清铜的浓度与肿瘤质量间具有相关性(r=0.316,P<0.05)。C、D、E组肿瘤组织中VEGF和bFGF mRNA的相对表达量与A组比较均明显升高,差异具有显著意义(F=40.118、197.090,P<0.05)。结论适宜的铜浓度能够影响H22移植瘤小鼠肿瘤的生长,可能是通过上调VEGF和bFGF mRNA的表达水平,从而达到促进肿瘤生长的作用,且其促进作用呈剂量依赖性。

Objective To investigate the effect of a suitable concentration of copper on tumor growth,liver function,and immune function by establishing a mouse model of H22 xenograft tumor. Methods A total of 80 specific pathogen-free Kunming mice were randomly divided into eight groups of A to H.Group A was given water by gavage,group B was given water＋terathiomolybdate（TM）by gavage,groups C,D,and E were given copper sulfate by gavage at a dose of 0.06,0.30,and 1.50 mg/kg,respectively,and groups F,G,and H were given copper sulfate（at a dose of 0.06,0.30,and 1.50 mg/kg,respectively）combined with 1 mg/kg TM by gavage.After copper sulfate was given by gavage for 4 weeks,H22 ascites tumor cells were inoculated into the right leg of the mice to establish a mouse model of H22 xenograft tumor.Then the groups were treated with copper sulfate for another 4 weeks.The mice were sacrificed 8 weeks later.ICP-MS was used to measure the serum concentration of copper;an automatic biochemical analyzer was used to measure the serum levels of aspartate aminotransferase（AST）,alanine aminotransferase（ALT）,and albumin（Alb）;quantitative real-time PCR was used to measure the mRNA expression of vascular endothelial growth factor（VEGF）and basic fibroblast growth factor（bFGF）in tumor tissue. Results Compared with groups A,F,G,and H,groups D and E showed significant increases in tumor growth（F=9.034,P〈0.05）.There were no significant differences between groups in the liver function parameters AST,ALT,and Alb,spleen index,and thymus index（P〉0.05）.ICP-MS showed that there was a significant difference in the serum level of copper between groups（F=3.803,P〈0.05）,and the serum level of copper was positively correlated with tumor mass（r=0.316,P〈0.05）.Compared with group A,groups C,D,and E had significant increases in the mRNA expression of VEGF and bFGF（F=40.118,197.090,P〈0.05）. Conclusion A suitable concentration of copper can promote the growth of H22 xenograft tumor in mice in a dose-dependent manner,possibly by upregulating the mRNA expression of VEGF and bFGF.