MET Inhibitors Promote Liver Tumor Evasion of the Immune Response by Stabilizing PDL1
MET Inhibitors Promote Liver Tumor Evasion of the Immune Response by Stabilizing PDL1
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MET 抑制剂通过稳定 PDL1 促进肝脏肿瘤逃避免疫反应
DOI：
10.1053/j.gastro.2019.01.252
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发表时间：
2019-05-01
期刊：
影响因子：
29.4
通讯作者：
Hung, Mien-Chie
中科院分区：
文献类型：
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作者：
Li, Hui;Li, Chia-Wei;Hung, Mien-Chie
背景与目的：MET抑制剂在肝癌患者的临床试验中尚未产生令人满意的结果。我们研究了小鼠肝肿瘤对MET抑制剂耐药的机制。方法：我们测试了MET抑制剂tivantinib和capmatinib在小鼠肝细胞癌（HCC）细胞系HCA-1中以及在具有从该细胞系生长的皮下肿瘤的免疫活性和免疫缺陷小鼠中的作用。从小鼠收集肿瘤，并通过飞行时间质谱细胞术分析肿瘤细胞。我们使用短发夹RNA来减弱Hep3B、SK-HEP-1、HA59 T和HA22 T肝癌细胞系中MET的表达，并通过免疫印迹、免疫荧光和免疫沉淀测定来分析细胞。质谱法用于评估肝癌细胞系中MET和糖原合成酶激酶3 β（GSK 3B）之间的相互作用以及GSK 3B磷酸化。给予具有从Hep1 - 6细胞生长的原位肿瘤的C57/BL6小鼠capmatinib或tivantinib和针对程序性细胞死亡1（PDCD 1;也称为PD 1）的抗体的组合;收集肿瘤并通过免疫荧光进行分析。我们分析了268 HCC组织芯片免疫组化。结果：暴露于MET抑制剂的肝癌细胞系增加了其PD配体1（PDL 1）的表达，并灭活了共培养的T细胞。MET磷酸化并激活GSK3B的酪氨酸56位，从而降低肝癌细胞PDL 1的表达。在免疫活性小鼠中生长的原位肿瘤中，MET抑制剂降低了T细胞的抗肿瘤活性。然而，与单独的抗PD1或MET抑制剂相比，添加抗PD1降低了原位肿瘤生长并延长了小鼠的生存期。HCC样本的组织微阵列分析显示MET和PDL 1水平之间呈负相关，MET和磷酸化GSK3B水平之间呈正相关。结论：在肝癌细胞系和原位肿瘤小鼠的研究中，MET介导磷酸化并激活GSK3B，导致PDL 1表达降低。与MET抑制剂组合，抗PD1和抗PDL1在小鼠中产生减缓HCC生长的累加效应。
BACKGROUND & AIMS: Inhibitors of MET have not produced satisfactory outcomes in trials of patients with liver cancer. We investigated the mechanisms of liver tumor resistance to MET inhibitors in mice. METHODS: We tested the effects of MET inhibitors tivantinib and capmatinib in the mouse hepatocellular carcinoma (HCC) cell line HCA-1 and in immune-competent and immunodeficient mice with subcutaneous tumors grown from this cell line. Tumors were collected from mice and tumor cells were analyzed by time-of-flight mass cytometry. We used short hairpin RNAs to weaken expression of MET in Hep3B, SK-HEP-1, HA59T, and HA22T liver cancer cell lines and analyzed cells by immunoblot, immunofluorescence, and immunoprecipitation assays. Mass spectrometry was used to assess interactions between MET and glycogen synthase kinase 3 beta (GSK3B), and GSK3B phosphorylation, in liver cancer cell lines. C57/BL6 mice with orthotopic tumors grown from Hep1-6 cells were given combinations of capmatinib or tivantinib and antibodies against programmed cell death 1 (PDCD1; also called PD1); tumors were collected and analyzed by immunofluorescence. We analyzed 268 HCCsamples in a tissue microarray by immunohistochemistry. RESULTS: Exposure of liver cancer cell lines to MET inhibitors increased their expression of PD ligand 1 (PDL1) and inactivated cocultured T cells. MET phosphorylated and activated GSK3B at tyrosine 56, which decreased the expression of PDL1 by liver cancer cells. In orthotopic tumors grown in immune-competent mice, MET inhibitors decreased the antitumor activity of T cells. However, addition of anti-PD1 decreased orthotopic tumor growth and prolonged survival of mice compared with anti-PD1 or MET inhibitors alone. Tissue microarray analysis of HCC samples showed an inverse correlation between levels of MET and PDL1 and a positive correlation between levels of MET and phosphorylated GSK3B. CONCLUSIONS: In studies of liver cancer cell lines and mice with orthotopic tumors, MET mediated phosphorylation and activated GSK3B, leading to decreased expression of PDL1. Combined with a MET inhibitor, anti-PD1 and anti-PDL1 produced additive effect to slow growth of HCCs in mice.