免疫抑制性细胞Treg和MDSCs与胃癌临床病理特征关系的研究

摘要

Background:The ability of tumor cells to evade destruction by immune system is known as tumor immune escape. Regulatory T cells( Treg cells)and myeloid-derived suppressor cells( MDSCs)are considered to be the most critical cell subsets participating in tumor immune escape. Aims:To determine the percentages of Treg cells and MDSCs in peripheral blood of patients with gastric cancer for investigating the effects of these two cell subsets on development and progression of gastric cancer. Methods:Peripheral blood specimens from 77 patients with gastric cancer and 20 healthy controls were collected for measurements of CD4+CD25+Foxp3+ Treg cells and MDSCs by flow cytometry. Correlations between Treg cells,MDSCs and clinicopathological characteristics of gastric cancer were analyzed. Results:Percentage of CD4+CD25+Foxp3 + Treg cells in peripheral blood CD4+ T cells and percentage of MDSCs in peripheral blood mononuclear cells were both significantly higher in gastric cancer patients than in healthy controls( Treg cells:4. 72% ± 1. 01% vs. 1. 57% ± 0. 99%,P<0. 01;MDSCs:21. 72% ± 10. 12% vs. 2. 90% ± 1. 80%,P<0. 01). Percentage of Treg cells in peripheral blood was correlated with the clinical stage,depth of invasion and lymph node metastasis of gastric cancer(P<0. 05), while percentage of MDSCs was correlated with the clinical stage of gastric cancer(P<0. 05). Furthermore,a significant positive correlation was observed between percentages of Treg cells and MDSCs in peripheral blood of gastric cancer patients ( rs =0. 681,P<0. 01). Conclusions:Gastric cancer patients are characterized by high expressions of immunosuppressive cells in peripheral blood,such as Treg cells and MDSCs,which might be related with the development and progression of gastric cancer via tumor immune escape.%背景：肿瘤细胞具有逃避机体免疫系统杀伤的免疫逃逸能力。调节性T细胞（ Treg细胞）和髓源抑制性细胞（ MDSCs）被认为是最为关键的参与肿瘤免疫逃逸机制的细胞亚群。目的：检测胃癌患者外周血Treg细胞、MDSCs比率，初步探讨两者在胃癌发生、发展中的作用。方法：收集77例胃癌患者和20名健康体检者的外周血标本，以流式细胞术检测CD4+CD25+Foxp3+ Treg细胞、MDSCs比率，分析两者与胃癌临床病理特征的关系以及两者间的相关性。结果：胃癌组外周血CD4+CD25+Foxp3+ Treg细胞在CD4+ T细胞中所占比率、MDSCs在单核细胞中所占比率均显著高于正常对照组（ Treg细胞：4.72%±1.01%对1.57%±0.99%，P<0.01；MDSCs：21.72%±10.12%对2.90%±1.80%，P<0.01）。胃癌患者外周血 Treg细胞比率与胃癌临床分期、浸润深度和淋巴结转移相关（P<0.05），MDSCs比率与胃癌临床分期相关（P<0.05），且 Treg细胞比率与 MDSCs比率呈显著正相关（rs =0.681，P<0.01）。结论：胃癌患者存在外周血免疫抑制性细胞Treg、MDSCs高表达现象，两者可能通过参与肿瘤免疫逃逸促进胃癌发生、发展。