基于质谱流式细胞技术揭示TP53突变型乙型肝炎病毒相关性肝细胞癌的免疫微环境特征

Characteristics of immune microenvironment of TP53 mutant HBV⁃related hepatocellular carcinoma revealed by CyTOF

目的探讨TP53突变型乙型肝炎病毒(hepatitis B virus,HBV)相关性肝细胞癌(hepatocellular carcinoma,HCC)的肿瘤免疫微环境特征。方法收集2018—2019年广西医科大学附属肿瘤医院肝胆外科手术切除的38例HCC患者活体组织标本及其配对癌旁组织标本,提取组织DNA,并进行基因突变分析。采用质谱流式细胞术(CyTOF)比较TP53突变组和TP53未突变组中癌组织与癌旁组织以及两组癌组织之间的免疫微环境特点。结果采用CyTOF鉴定TP53突变组和TP53未突变组所有免疫细胞,结果鉴定为22个细胞亚群,包括CD4+T细胞亚群、CD8+T细胞亚群、B细胞亚群、树突细胞亚群、自然杀伤(natural killer cell,NK)细胞亚群、NKT细胞亚群、粒细胞亚群和2个未知细胞亚群。其中,TP53突变组癌组织中CD8+T细胞和CD4+T细胞的表达比例均较未突变组癌组织高(2.26%vs 0.47%,P=0.028;7.53%vs 3.55%,P=0.046)。结论TP53突变型HBV相关性HCC的肿瘤免疫微环境具有免疫异质性。

Objective To investigate the characteristics of tumor immune microenvironment of TP53 mutant hepatitis B virus(HBV)⁃associated hepatocellular carcinoma(HCC).Methods The living tissue samples and paired paracancerous tissue samples of 38 HCC patients who underwent hepatobiliary surgery in Hepatobiliary Surgery Department of Guangxi Medical University Cancer Hospital from 2018 to 2019 were collected,DNAs of tissues were extracted,and gene mutation was analyzed.Mass spectrometry flow cytometry(CyTOF)was used to compare the characteristics ofthe immune microenvironments in and between the cancer tissues and paired paracan⁃cerous tissues of the TP53 mutated group and TP53 unmutated group.Results CyTOF was used to identify the immune cells in TP53 mutated group and TP53 unmutated group,and the results were identified as 22 cell subsets,including CD4+T⁃cell subsets,CD8+T⁃cell subsets,B⁃cell subsets,dendritic cell subsets,natural killer(NK)cell subsets,NKT cell subsets,granulocyte subsets and two unknown cell subsets.Among them,the expression ratio of CD8+T cells and CD4+T cells in TP53 mutated group was higher than that in TP53 unmutated group(2.26%vs 0.47%,P=0.028;7.53%vs 3.55%,P=0.046).Conclusions The tumor immune microenvironment of TP53 mutant HBV⁃associated HCC has immune heterogeneity.