胃癌患者免疫微环境中表型特征及其与临床病理参数和预后的关系

Study of immunophenotypic characteristics,clinicopathological parameters and prognosis in gastric cancer microenvironment

目的探究胃癌患者免疫微环境中的表型特征,分析其与临床病理参数及预后的关系。方法纳入研究的92例胃癌组织[男58例,女34例;年龄M(Q_(1),Q_(3)),70(59,77)岁]及84例癌旁组织[男57例,女27例,年龄70(59,77)岁]购自上海芯超生物科技有限公司,标本来自样本库中的28家医院,检测其白细胞分化抗原(CD)8、CD4、T淋巴细胞免疫球蛋白黏蛋白3(TIM3)、人叉头盒蛋白P3(Foxp3)及共定位肿瘤浸润性淋巴细胞(TILs)亚群的表达水平。根据各阳性淋巴细胞百分比的最佳截断值将胃癌及癌旁组织分别分为高表达组和低表达组,分析各免疫表型在胃癌及癌旁组织中的表达量;采用Kaplan-Meier法进行生存分析;采用Cox比例风险模型探究胃癌患者预后的影响因素。结果胃癌组织中CD8、CD4、TIM3和Foxp3阳性细胞百分比的最佳截断值分别为12.73%、1.39%、10.77%和2.44%;胃癌组织中Foxp3的表达量高于癌旁组织[M(Q_(1),Q_(3)),0.93(0.45,2.16)比0.31(0.09,0.86),P<0.001];CD8[4.92(2.34,8.80)比8.81(6.61,12.17),P<0.001]、CD4[4.79(1.77,11.36)比8.40(4.84,12.77),P=0.022]和TIM3[5.68(2.05,11.58)比7.07(3.13,11.43),P=0.338]的表达量低于癌旁组织;不同淋巴结转移和临床分期的胃癌患者中TIM3表达量的差异均有统计学意义(均P<0.05)。胃癌组织中CD4高表达、TIM3低表达和Foxp3低表达的患者5年生存率均较差,其中CD4高、低表达组分别为29.3%、64.7%;TIM3高、低表达组分别为60.9%、30.4%;Foxp 3高、低表达组分别为64.3%、33.3%(均P<0.05)。胃癌组织中共定位CD8^(+)TIM3+TILs、CD4^(+)TIM3+TILs、CD8^(+)Foxp3^(+)TILs、CD4^(+)Foxp3^(+)TILs阳性细胞百分比的最佳截断值分别为3.86%、0.23%、0.08%、0.76%;胃癌组织中CD8^(+)Foxp3^(+)TILs的表达量高于癌旁组织(P<0.05)。多因素Cox回归分析显示CD4高表达(HR=3.079,95%CI:1.350~7.024,P=0.008)、TIM3低表达(HR=0.428,95%CI:0.208~0.879,P=0.021)、Foxp3低表达(HR=0.288,95%CI:0.121~0.687,P=0.005)是胃癌患者术后5年生存率的影响因素。结论胃癌患者具有复杂的免疫微环境特征,CD4、TIM3、Foxp3的表达量与患者预后密切相关。

Objective To explore the immunophenotypic characteristics of gastric cancer microenvironment and analyze its correlation with clinicopathological parameters and prognosis of patients.Methods The expression levels of leukocyte differentiation antigen(CD)8,CD4,T lymphocyte immunoglobulin mucoprotein 3(TIM3),human forkhead box protein P3(Foxp3)and co-localized tumor infiltrating lymphocytes(TILs)were detected in 92 cases of gastric cancer tissue[58 males and 34 females;aged M(Q_(1),Q_(3)),70(59,77)years]and 84 cases of paracancer tissue[57 males and 27 females,aged 70(59,77)years]purchased from Shanghai Xinchao Biotechnology Co.,Ltd.,and the samples were from 28 hospitals in the sample bank.Gastric cancer and adjacent tissues were divided into high expression group and low expression group according to the optimal cut-off value of positive lymphocytepercentage.The expression of immunophenotypes in gastric cancer and adjacent tissues was analyzed.Kaplan-Meier method was used for survival analysis.Cox proportional hazard model was used to explore the prognostic factors of gastric cancer patients.Results The optimal cut-off values of CD8,CD4,TIM3 and Foxp3 positive cells in gastric cancer were 12.73%,1.39%,10.77%and 2.44%,respectively.The expression of Foxp3 in gastric cancer tissues was higher than that in paracancer tissues[M(Q_(1),Q_(3)),0.93(0.45,2.16)vs 0.31(0.09,0.86),P<0.001],and the expression of CD8[4.92(2.34,8.80)vs 8.81(6.61,12.17),P<0.001],CD4[4.79(1.77,11.36)vs 8.40(4.84,12.77),P=0.022]and TIM3[5.68(2.05,11.58)vs 7.07(3.13,11.43),P=0.338]were lower than that in paracancer tissues.There were significant differences in TIM3 expression in gastric cancer patients with different lymph node metastasis and clinical stage(all P<0.05).The 5-year survival rate of patients with high CD4 expression,low TIM3 expression and low Foxp3 expression in gastric cancer tissues was poor,among which the high CD4 expression and low CD4 expression groups were 29.3%and 64.7%,respectively;The high and low TIM3 expression groups were 60.9%and 30.4%,respectively;The high and low Foxp3 expression groups were 64.3%and 33.3%,respectively(all P<0.05).The optimal cut-off values of CD8^(+)TIM3+TILs,CD4^(+)TIM3+TILs,CD8^(+)Foxp3^(+)TILs and CD4^(+)Foxp3^(+)TILs were 3.86%,0.23%,0.08%and 0.76%,respectively.Colocalization analysis showed that the expression of CD8^(+)Foxp3^(+)TILs in gastric cancer tissues was higher than that in adjacent tissues(all P<0.05).Multivariate Cox regression analysis showed that high expression of CD4(HR=3.079,95%CI:1.350-7.024,P=0.008),low expression of TIM3(HR=0.428,95%CI:0.208-0.879,P=0.021)and low expression of Foxp3(HR=0.288,95%CI:0.121-0.687,P=0.005)were the influencing factor for the 5-year survival rate of patients with gastric cancer after operation.Conclusions Gastric cancer tissues have complex immune microenvironment characteristics.The expression of CD4,TIM3 and Foxp3 is closely related to the prognosis of patients.