低剂量环磷酰胺抑制结肠癌肝转移的免疫调节机制研究  

Low dose cyclophosphamide inhibiting the liver metastasis of colon cancer by regulating immunity

作　　者：黄晓明[1] 张南荣[2] 邹一丰[3] 何晓生[3] 林绪涛[3,4] 兰平[3] 万云乐[1] 

机构地区：[1]广东省胃肠病学研究所广东省结直肠盆底疾病研究重点实验室中山大学附属第六医院肝胆外科,广州510655 [2]广东省胃肠病学研究所广东省结直肠盆底疾病研究重点实验室中山大学附属第六医院手术麻醉科,广州510655 [3]广东省胃肠病学研究所广东省结直肠盆底疾病研究重点实验室中山大学附属第六医院结直肠外科,广州510655 [4]广东省胃肠病学研究所广东省结直肠盆底疾病研究重点实验室中山大学附属第六医院消化内镜科,广州510655

出　　处：《中华普通外科学文献（电子版）》2017年第6期365-369,共5页Chinese Archives of General Surgery(Electronic Edition)

基　　金：广东省医学科学技术研究基金项目(A2016198)

摘　　要：目的探讨低剂量环磷酰胺抑制结肠癌肝转移的免疫调节机制。方法将30只小鼠随机分为5组,采用脾脏注射小鼠结肠癌CT26细胞方法建立小鼠结肠癌肝转移模型,在不同时点将低剂量的CTX(20 mg/kg)注入治疗组小鼠体内。采用流式细胞仪来检测肝和脾脏组织中的T细胞标记物(CD8+、CD4+T细胞)数量,免疫组织化学方法对肝组织的白细胞介素10(IL-10)和转化生长因子β1(TGF-β1)蛋白表达情况进行分析,酶联免疫吸附法(ELISA)检测血清中的干扰素γ(IFN-γ)和IL-10的蛋白质量浓度。结果小鼠结肠癌肝转移模型中CD4+T细胞、CD8+T细胞数量和百分比和IFN-γ都出现了下调,而IL-10和TGF-β1的蛋白表达量则明显升高。同时,肝脏的系统及局部免疫微环境发生了变化,导致抗肿瘤免疫反应的细胞数量减少,促进了结肠癌肝转移的发生。而使用低剂量的CTX治疗后增强了细胞抗肿瘤免疫反应,抑制IL-10和TGF-β1的蛋白表达,诱导IFN-γ蛋白分泌。结论低剂量的CTX通过改变小鼠肝脏局部和系统免疫微环境来增强小鼠的免疫调节能力,从而增强小鼠肝脏的抗肿瘤免疫作用。因此CTX可以被用来预防/治疗结肠癌肝转移。Objective To investigate the underlying mechanism of low-dose cyclophosphamide inhibiting the liver metastasis of colon cancer by regulating immunity. Methods Thirty mice were randomly divided into five groups. After the establishment of liver metastasis in colon cancer models, mice in treatment groups were injected with low-dose cyclophosphamide （CTX, 20 mg/kg） at different time points. The liver and spleen tissues were examined for T cell markers via flow cytometry. IL-10 and TGF-β1 expression in liver tissues was analyzed by immunohistochemistry. Serum IFN-γ and IL-10 levels were detected by ELISA. Results This study showed that the expression of CD4＋ T cells, CD8＋ T cells, and IFN-γ were downregulated while the expression of IL-10 and TGF-β1 was upregulated in the liver metastasis of colon cancer in mice. Further, the local and systemic microenvironments of the liver were changed, leading to reduced antitumor immune responses and thus the liver metastasis. However, treatment with low-dose CTX could enhance antitumor immune response, inhibit the expression of IL-10 and TGF-β1, and induce secretion of IFN-γ. Conclusions Low-dose CTX exerts its antitumor activity by changing the systemic and local immune microenvironments and enhancing immune regulation in mice. CTX may be used as a drug for preventing/treating the liver metastasis of colon cancer.

关 键 词：结肠肿瘤 环磷酰胺 肿瘤转移 肿瘤微环境 

分 类 号：R735.35[医药卫生—肿瘤]