摘要
目的:检测低剂量环磷酰胺(cyclophosphamide,CYC)腹腔注射对黑素瘤荷瘤小鼠体内微环境中调节性T细胞(regulatory T cells,Treg)、免疫抑制因子白细胞介素-10(interleukin-10,IL-10)及转化生长因子-β(transforming growth factor beta,TGF-β)水平的影响,探讨CYC介导抑制肿瘤微环境的分子机制。方法:建立小鼠荷黑素瘤B16细胞模型,模型鼠随机分为实验组(CYC腹腔注射,每只20 mg/kg)和对照组(同体积0.9%NaCl溶液腹腔注射)。注射前和注射后1、4、7、11和15 d,用流式细胞仪检测小鼠外周血和瘤组织内CD4+CD25+Foxp3+Treg百分率;ELISA法检测血清和肿瘤组织中IL-10和TGF-β水平;观察比较各组荷瘤小鼠的肿瘤生长情况。结果:与对照组相比,实验组小鼠外周血和肿瘤组织中Treg百分率以及IL-10和TGF-β表达水平均明显降低(P<0.05);实验组小鼠外周血及肿瘤组织中Treg百分率和IL-10水平变化均正相关(外周血:rs=0.943,P=0.005;肿瘤组织:rs=0.812,P=0.050)。2组小鼠肿瘤生长差异无统计学意义(P>0.05)。结论:腹腔注射低剂量CYC可降低荷瘤小鼠外周血和肿瘤组织中Treg百分率和免疫抑制因子IL-10、TGF-β水平,从而有效干预荷瘤小鼠体内免疫抑制微环境,但对肿瘤生长无明显抑制作用。
Objective： To explore the mechanism of cyclophosphamide （CYC）-mediated inhibition of tumor microenvironment by examining the percentages of regulatory T cells （Tregs） and the levels of immunosuppressive cytokine interleukin-10 （IL-10） and transforming growth factor beta （TGF-β） in melanoma-bearing mice after administration of low-dose CYC. Methods： The B16 melanoma-bearing mouse model was established, and then the mice were randomly divided into CYC group （20 mg/kg by intraperitoneal injection） and control group （equal volume of normal saline by intraperitoneal injection）. The percentages of CD4^＋CD25^＋Foxp3^＋ Tregs in peripherial blood （PB） and tumor tissues were determined with flow cytometry. The levels of TGF-β and IL-10 were detected by enzyme-linked immunosorbent assay before injection and 1,4, 7, 11 and 15 days after CYC or NS injection. The tumor size was observed and compared between the two groups. Results： As compared with the control group, the percentage of Tregs and the levels of TGF-β and IL-10 in CYC group were obviously decreased （P 〈 0.05）. In CYC group, a positive correlation existed between the percentage of Tregs and the level of IL-10 （PB： rs = 0.943, P = 0.005; tumor tissue： rs = 0.812, P = 0.050）. There was no significant difference in tumor growth between the two groups （P 〉 0.05）. Conclusion： Low-dose CYC can relieve immunosuppression and control the immune escape by reducing the percentage of Tregs and the levels of IL-10 and TGF-β in PB and tumor tissues, but has no inhibitive effect on tumor growth.
出处
《肿瘤》
CAS
CSCD
北大核心
2014年第4期331-336,共6页
Tumor
基金
河北省科技支撑计划项目(编号:10246139D)
