卵巢癌细胞通过P38 MAPK通路促进CD8^+调节T细胞的生成

Ovarian cancer cells promote the generation of CD8^+ regulatory T cells through P38 MAPK signaling

目的探讨丝裂原活化蛋白激酶(MAPK)信号通路在卵巢癌细胞(SKOV3)诱导CD8+Treg分化过程中的作用。方法建立SKOV3与健康人CD8+T细胞体外共培养体系,设置CD8+T细胞单独培养组为对照组。共培养5 d后,收集各组CD8+T细胞,荧光定量PCR和流式细胞术检测CD8+T细胞中Treg相关标志物(CD25、Foxp3、CD28)的表达率;功能抑制试验检测两组CD8+T细胞对nave CD4+T细胞增殖能力的影响;Western blot检测MAPK通路相关蛋白(ERK/p-ERK、JNK/p-JNK、P38 MAPK/p-P38 MAPK)的表达水平;P38 MAPK特异性抑制剂SB203580预处理CD8+T细胞后,评价CD8+T细胞中Treg相关标志物(CD25、Foxp3、CD28)的表达变化。结果共培养组CD8+T细胞中CD25及Foxp3表达率均显著高于对照组(P<0.05),CD28表达率显著低于对照组(P<0.05);共培养组CD8+T细胞相比对照组,抑制nave CD4+T细胞的增殖力增强;Western blot结果显示,共培养组p-P38 MAPK的表达水平显著高于对照组(P<0.05),SB203580预处理后CD8+T细胞中Treg相关标志物表达率均下调。结论卵巢癌细胞通过活化CD8+T细胞的P38 MAPK信号通路诱导具有抑制作用的CD8+Treg的生成,促进肿瘤进展。

Objective To investigate the effects of mitogen-activated protein kinase（ MAPK） signaling pathway on the differentiation of CD8＋regulatory T cells induced by ovarian cancer cell line SKOV3. Methods Coculture systerm of CD8＋T cells and SKOV3 was conducted in vitro,CD8＋T cells cultured alone group acted as control group. At day 5,CD8＋T cells were collected,mRNA and protein expression level of CD28,CD25,Foxp3 in CD8＋T cells were detected by real-time PCR and flow cytometry. Western blot was used to detect the expression of p-ERK,ERK,p-JNK,JNK,p-P38 MAPK and P38 MAPK. Proliferation assay was applied to analyze the effect of CD8＋T cells on nave CD4＋T cells. The phenotypic changes of CD8＋T cells were determined after 4 hours pre-incubation with the specific inhibitors of P38 MAPK（ SB203580）. Results In co-cultured group the mRNA and protein expression of CD25 and Foxp3 were higher than those in the control group（ P 〈 0. 05）; and the expressionof CD28 was significantly lower than that in the control group（ P 〈 0. 05）; The expression of p-P38 MAPK in the co-cultured group was significant higher than that in the control group（ P 〈 0. 05）; After pre-incubated with SB203580 for 4 hours,the phenotypic of CD8＋Tregs significantly decreased. Conclusions P38 MAP Kinase signaling is required for the generation of CD8＋Tregs induced by ovarian cancer cell,which facilitates tumor growth.