Jiang Jinhua, Liu Feng, Cui Dan, Xu Caixia, Chi Jiachang, Yan Tinghua, Guo Fang
Department of Interventional Oncology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, P. R. China.
Key Laboratory of Systems Biomedicine, Ministry of Education, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, P. R. China.
Cancer Commun (Lond). 2025 Apr 14. doi: 10.1002/cac2.70023.
Hepatocellular carcinoma (HCC) is a deadly malignancy known for its ability to evade immune surveillance. NOP2/Sun RNA methyltransferase family member 2 (NSUN2), an RNA methyltransferase involved in carcinogenesis, has been associated with immune evasion and energy metabolism reprogramming. This study aimed to examine the molecular mechanisms underlying the involvement of NSUN2 in immune evasion and metabolic reprogramming of HCC.
Single-cell transcriptomic sequencing was applied to examine cellular composition changes, particularly immune cell dynamics, in HCC and adjacent normal tissues. Bulk RNA-seq and proteomics identified key genes and proteins. Methylation sequencing and methylated RNA immunoprecipitation (MeRIP) were carried out to characterize the role of NSUN2 in 5-methylcytosine (m5C) modification of sterol O-acyltransferase 2 (SOAT2). Clinical samples from 30 HCC patients were analyzed using reverse transcription-quantitative polymerase chain reaction and Western blotting. Gene expression was manipulated using CRISPR/Cas9 and lentiviral vectors. In vitro co-culture models and metabolomics were used to study HCC cell-T cell interactions, energy metabolism, and immune evasion. Tumor growth in an orthotopic mouse model was monitored by bioluminescence imaging, with subsequent measurements of tumor weight, volume, and immunohistochemical staining.
Single-cell transcriptomic analysis identified a marked increase in malignant cells in HCC tissues. Cell communication analysis indicated that tumor cells might promote cancer progression by evading immune clearance. Multi-omics analyses identified NSUN2 as a key regulator in HCC development. MeRIP confirmed that NSUN2 facilitated the m5C modification of SOAT2. Analysis of human HCC tissue samples demonstrated pronounced upregulation of NSUN2 and SOAT2, along with elevated m5C levels in HCC tissues. In vitro experiments uncovered that NSUN2 augmented the reprogramming of energy metabolism and repressed the activity and cytotoxicity of CD8 T cells, contributing to immune evasion. In vivo studies further substantiated the role of NSUN2 in fostering immune evasion and tumor formation of HCC by modulating the m5C modification of SOAT2.
The findings highlight the critical role of NSUN2 in driving HCC progression through the regulation of m5C modification on SOAT2. These findings present potential molecular markers for HCC diagnosis and therapeutic targets for its treatment.
肝细胞癌（HCC）是一种致命的恶性肿瘤，以其逃避免疫监视的能力而闻名。NOP2/Sun RNA甲基转移酶家族成员2（NSUN2）是一种参与致癌作用的RNA甲基转移酶，与免疫逃逸和能量代谢重编程有关。本研究旨在探讨NSUN2参与HCC免疫逃逸和代谢重编程的分子机制。
应用单细胞转录组测序来检测HCC组织和相邻正常组织中的细胞组成变化，特别是免疫细胞动态。批量RNA测序和蛋白质组学鉴定关键基因和蛋白质。进行甲基化测序和甲基化RNA免疫沉淀（MeRIP）以表征NSUN2在固醇O-酰基转移酶2（SOAT2）的5-甲基胞嘧啶（m5C）修饰中的作用。使用逆转录定量聚合酶链反应和蛋白质印迹法分析30例HCC患者的临床样本。使用CRISPR/Cas9和慢病毒载体来调控基因表达。体外共培养模型和代谢组学用于研究HCC细胞与T细胞的相互作用、能量代谢和免疫逃逸。通过生物发光成像监测原位小鼠模型中的肿瘤生长，随后测量肿瘤重量及其体积，并进行免疫组织化学染色。
单细胞转录组分析确定HCC组织中恶性细胞显著增加。细胞通讯分析表明肿瘤细胞可能通过逃避免疫清除来促进癌症进展。多组学分析确定NSUN2是HCC发展中的关键调节因子。MeRIP证实NSUN2促进了SOAT2的m5C修饰。对人HCC组织样本的分析表明，HCC组织中NSUN2和SOAT2明显上调，同时m5C水平升高。体外实验发现，NSUN2增强了能量代谢重编程，并抑制了CD8 T细胞的活性和细胞毒性，从而导致免疫逃逸。体内研究进一步证实了NSUN2通过调节SOAT2的m5C修饰在促进HCC免疫逃逸和肿瘤形成中的作用。
这些发现突出了NSUN2通过调节SOAT2的m5C修饰在推动HCC进展中的关键作用。这些发现为HCC诊断提供了潜在的分子标志物，并为其治疗提供了治疗靶点。
