黄芪四君子汤调节T细胞PD1泛素化水平重塑肿瘤免疫微环境抑制胃癌增殖的研究

Huangqi Sijunzi Decoction Restrained Gastric Cancer Proliferation via Regulating the Level of PD1 Ubiquitination on T Cells and Remodeling the Tumor Immune Microenvironment

目的探讨黄芪四君子汤对MFC胃癌荷瘤小鼠肿瘤增殖及免疫功能的影响。方法建立C57BL/6小鼠MFC胃癌皮下荷瘤模型,采用随机数字表法,将24只C57BL/6小鼠分为空白对照组、模型组、中药低剂量组(6.24 g·kg^(-1))、中药高剂量组(12.48 g·kg^(-1)),每组6只;记录小鼠体质量,计算肿瘤体积;ELISA法检测各组小鼠外周血中IFN-γ、IL-2、IL-8和TNF-α表达水平;应用流式细胞术分别检测小鼠肿瘤、脾脏和胸腺中CD4^(+)、CD8^(+)、PD1^(+)T细胞亚群的表达水平;检测小鼠肿瘤中PD1泛素化水平。结果与空白对照组比较,皮下荷瘤模型组小鼠体质量增加(P<0.05),外周血中IFN-γ、IL-2和TNF-α表达水平降低(P<0.001)、IL-8表达升高(P<0.05)。与模型组相比,中药高剂量组小鼠肿瘤大小明显低于模型组(P<0.05),外周血中IFN-γ、IL-2和TNF-α表达水平显著上升(P<0.001,P<0.01),而IL-8的表达水平显著降低(P<0.05);中药高剂量组小鼠的肿瘤、脾脏和胸腺中CD4^(+)、CD8^(+)T细胞亚群表达均增加(P<0.001),PD1^(+)T细胞则随着其泛素化水平增加(P<0.01)而表达下降(P<0.001)。结论黄芪四君子汤可上调MFC荷瘤小鼠CD4^(+)、CD8^(+)T细胞表达,调节外周血中细胞因子的表达水平,并通过增加T细胞胞内泛素化水平,促使PD1表达下调,从而抑制胃癌细胞的增殖。

OBJECTIVE To evaluate the effects of Huangqi Sijunzi Decoction on tumor proliferation and immune function of MFC gastric cancer bearing mice.METHODS The MFC gastric cancer subcutaneous tumor model of C57BL/6 mouse was established.24 C57BL/6 mice were divided into control group,model group,low dose Chinese medicine group(6.24 g·kg^(-1))and high dose Chinese medicine group(12.48 g·kg^(-1)),with 6 mice in each group.The body weight and tumor volume of these mice were recorded.Expression levels of IFN-γ,TNF-α,IL-2 and IL-8 in peripheral blood of mice in each group were detected by ELISA.The expression levels of CD4^(+),CD8^(+),and PD1^(+)T cell subsets in the tumor,spleen,and thymus of mice were analyzed by flow cytometry.Detect PD1 ubiquitination levels in mouse tumors.RESULTS Compared with control group,the body weight was increased(P<0.05),the expression of IFN-γ,TNF-α,IL-2 were decreased(P<0.001),and the expression of IL-8 was increased in model group(P<0.05).Compared with model group,the tumor volume of mice in high dose Chinese medicine group was remarkable declined(P<0.05).The expression levels of IFN-γ,IL-2,TNF-αin mouse peripheral blood increased(P<0.01,P<0.001),but the expression level of IL-8 decreased(P<0.05).The expression of CD4^(+)and CD8^(+)T cell subsets in tumor,spleen,and thymus of mice was increased in high dose Chinese medicine group(P<0.001).The PD1^(+)T cells were decreased(P<0.001)with the increase of ubiquitination level(P<0.01).CONCLUSION Huangqi Sijunzi Decoction can upregulate the expression of CD4^(+)and CD8^(+)T cells in MFC tumor bearing mice,regulate the expression level of cytokines in peripheral blood,and promote the downregulation of PD1 expression by increasing the level of intracellular ubiquitination of T cells,thus inhibiting the proliferation of gastric cancer cells.