SOX2影响PD-L1表达参与乳腺癌细胞免疫逃逸的机制探讨  

Mechanism of SOX2 Induced PD-L1 Expression Promoting Immune Escape of Breast Cancer Cells

作　　者：张小燕 尚红梅 汪丹丹 陈芳 王海燕 郭晨明 ZHANG Xiao-yan;SHANG Hong-mei;WANG Dan-dan;CHEN Fang;WANG Hai-yan;GUO Chen-ming(Department of Breast,Center ofDigestive and Vascular,The First Affiliated Hospital of Xinjiang Medical University,Urumqi,Xinjiang,830011,China)

机构地区：[1]新疆医科大学第一附属医院消化血管外科中心乳腺外科,新疆乌鲁木齐830011

出　　处：《现代生物医学进展》2024年第9期1628-1632,共5页Progress in Modern Biomedicine

基　　金：新疆维吾尔自治区自然科学基金项目(2022D01A140)。

摘　　要：目的:探讨转录因子性别决定区Y框蛋白2(SOX2)基因通过诱导程序性死亡因子配体1(PD-L1)表达,促进乳腺癌细胞免疫逃逸的作用机制。方法:qRT-PCR和Western blot法检测人乳腺癌细胞系MDA-MB-231、SK-BR-3和正常乳腺上皮细胞系MCF10A中SOX2、PD-L1、T细胞免疫球蛋白及粘蛋白结构域分子3(TIM3)和核受体亚家族4 A组成员1(NR4A1)的mRNA表达量及对应蛋白表达量。分别构建SOX2敲减质粒NC和si-SOX2并转染MDA-MB-231,与细胞因子诱导的杀伤细胞构建共培养体系,连续培养48h,MTT法检测细胞增殖率,TUNEL法检测细胞凋亡率,乳酸脱氢酶(LDH)释放实验检测T细胞杀伤率,ELISA检测T细胞活化标志物IL-2和IFN-γ,qRT-PCR检测T细胞耗竭标志物PD-1、TIM3和NR4A1 mRNA表达量。结果:与MCF10A相比,MDA-MB-231与SK-BR-3中SOX2、PD-L1、TIM3、NR4A1的m RNA表达量及对应蛋白表达量均显著升高(P<0.05)。与空白组和NC组相比,si-SOX2组SOX2 mRNA和PD-L1蛋白表达量明显下降,细胞增殖率显著下降,细胞凋亡率增加,T细胞杀伤率增加,IL-2和IFN-γ水平升高,PD-1、TIM3和NR4A1 mRNA表达量降低(P<0.05)。结论:SOX2基因可能通过诱导PD-L1高表达,进而促使乳腺癌细胞免疫逃逸的能力增强,沉默SOX2表达可以增强T细胞杀伤力,抑制肿瘤增殖,SOX2基因有望成为乳腺癌干预的重要分子靶点。Objective:To investigate the mechanism of transcription factor sex determining region Y box protein 2(SOX2)gene promoting immune escape of breast cancer cells by inducing the expression of programmed death factor ligand 1(PD-L1).Methods:The expressions of SOX2,PD-L1,T cell immunoglobulin and mucin domain molecule 3(TIM3),and nuclear receptor subfamily 4A group member 1(NR4A1)mRNA and corresponding protein expressions in human breast cancer cell lines MDA-MB-231,SK-BR-3 and normal breast epithelial cell line MCF10A were detected by qRT-PCR,and Western blot.SOX2 knockdown plasmids NC and si-SOX2 were constructed,transfected with MDA-MB-231,and constructed a coculture system with cytokine induced killer cells.They were continuously cultured for 48 hours,cell proliferation rate was detected by MTT assay,apoptosis rate was detected by TUNEL assay,T cell killing rate was detected by lactate dehydrogenase(LDH)release assay,T cell activation markers IL-2 and IFN-γ were detected by ELISA,the mRNA expression levels of T cell depletion marker PD-1,TIM3,and NR4A1 were detected by qRT-PCR.Results:Compared with MCF10A,the expression levels of SOX2,PD-L1,TIM3,NR4A1 mRNA and corresponding protein expressions in MDA-MB-231 and SK-BR-3 were significantly increased(P<0.05).Compared with the blank group and NC group,the si-SOX2 group showed significant decrease in the expressions of SOX2 mRNA and PD-L1 protein,significant decrease in cell proliferation rate,increase in cell apoptosis rate,increase in T cell killing rate,increase in IL-2 and IFN-γlevels,decrease in the mRNA expression levels of PD-1,TIM3,and NR4A1(P<0.05).Conclusion:SOX2 gene may enhance the immune escape ability of breast cancer cells by inducing high expression of PD-L1.Silencing SOX2 expression can enhance the lethality of T cells and inhibit tumor proliferation.SOX2 gene is expected to become an important molecular target of breast cancer intervention.

关 键 词：乳腺癌 免疫逃逸 转录因子性别决定区Y框蛋白2 程序性死亡因子配体1 

分 类 号：R-33[医药卫生] R737.9