阻断PD-L1在增强奥沙利铂治疗原发性肝细胞肝癌疗效中的实验研究  

The efficacy of blocking PD-L1 in the treatment of primary hepatocellular carcinoma with oxaliplatin

作　　者：尹锠杰 高辉[2] 李华[2] 原薇薇 蒋朝阳[2] 周进军[2] 陈育林 王涛[2] 王丹[2] 张涛[2] 

机构地区：[1]陆军军医大学(第三军医大学)研究生管理大队,重庆400038 [2]成都军区总医院肿瘤诊治中心,610083

出　　处：《免疫学杂志》2017年第12期1066-1070,共5页Immunological Journal

基　　金：四川省科技厅重点研发项目(2017SZ0066)

摘　　要：目的初步探讨阻断程序性死亡-配体1(programmed death-ligand 1,PD-L1)在增强奥沙利铂(oxaliplatin,L-OHP)治疗原发性肝细胞肝癌(hepatocellular carcinoma,HCC)疗效中的作用及其分子机制。方法 L-OHP处理人HCC细胞系HepG2后,q RT-PCR和Western blot检测PD-L1在m RNA及蛋白水平的表达变化,以及细胞外调节蛋白激酶1/2(extracellular regulated protein kinases,ERK1/2)磷酸化水平的改变;建立Hepa1-6细胞C57BL/6J小鼠HCC移植瘤模型,随机分为对照组、L-OHP组、PD-L1单抗组、L-OHP+PD-L1单抗组,计算处理后各组小鼠肿瘤的质量、抑制率和生存时间;体外刺激或抑制HepG2细胞系ERK1/2的磷酸化,L-OHP处理后q RT-PCR和Western blot检测PD-L1的表达变化。结果 L-OHP能显著抑制HepG2细胞系的生长,其IC50分别为20.94 mg/L;L-OHP处理HepG2细胞后,p-ERK1/2和PD-L1的表达量均高于对照组(P<0.05)。小鼠HCC移植瘤模型中,与对照组、L-OHP组和PD-L1单抗组相比较,L-OHP+PD-L1单抗组的肿瘤质量显著减小(P<0.05),肿瘤抑制率大幅提升(P<0.05),生存时间明显延长(P<0.05)。体外刺激ERK1/2的磷酸化后,PD-L1表达显著上调,而抑制HCC细胞株ERK1/2的磷酸化后,L-OHP诱导PD-L1表达升高效应明显受到抑制。结论 L-OHP能通过提高ERK1/2磷酸化水平上调HCC细胞的PD-L1表达,从而导致治疗失败,而联合PD-L1单抗可显著增强L-OHP的抗HCC作用。This study was designed to investigate the efficacy of blocking PD-L1 in the treatment of primaryhepatocellular carcinoma（HCC） with oxaliplatin（L-OHP） and its mechanisms.HepG2 cells were treated withL-OHP,and then q RT-PCR and Western blotting were employed to detect the expression of PD-L1 and the level ofp-ERK1/2.The mouse xenografts model of HCC was established by Hepa1-6 cells,and divided into 4 groupsrandomly： control group,L-OHP group,anti-PD-L1 group,L-OHP＋anti-PD-L1 group.Average tumor volume andtumor inhibitory rate were calculated after treatment in all groups.q RT-PCR and Western blot were employed tomeasure the expression of PD-L1 after promoting or inhibiting the phosphorylation of ERK1/2 of HepG2 andHepa1-6.Data showed that L-OHP could inhibit the growth of HepG2 cells observably,with IC50 value of 20.94 mg/L.The treatment of L-OHP could increase p-ERK1/2 and PD-L1（P〈0.05）.In mouse xenografts models of HCC,L-OHP＋anti-PD-L1 group demonstrated less average tumor volume（P〈0.05）,higher tumor inhibitory rate（P〈0.05）and longer survival time（P〈0.05）,as compared withcontrol group.After promoting or inhibiting thephosphorylation of ERK1/2 of HepG2,the expressionof PD-L1 was obviously elevated or reduced,correspondingly.In conclusion,L-OHP could up-regulate the expression of PD-L1 in HCC cells via increasing thelevel of ERK1/2 phosphorylation and result in treatment failure,while combination with anti-PD-L1 could enhancethe effect of anti-HCC of L-OHP.

关 键 词：PD-L1 奥沙利铂(L-OHP) 原发性肝细胞肝癌 ERK1/2磷酸化 

分 类 号：R735.7[医药卫生—肿瘤]