PO.ET06.04 · 实验与分子治疗
LTA4H通过mTOR激活和T细胞耗竭促进肝内胆管癌进展
LTA4H promotes intrahepatic cholangiocarcinoma progression via mTOR activation and T-cell exhaustion
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
引言：肝内胆管癌（ICC）是一种高度侵袭性的肝癌，预后不良。免疫逃逸在ICC进展中发挥关键作用。白三烯A4水解酶（LTA4H）是类二十烷酸代谢中的一种关键酶，在多种癌症类型中过表达；然而，其在ICC中的作用和机制仍完全未被探索。
方法：在两个独立的ICC队列（n=130）和细胞系中，采用生物信息学、免疫组织化学（IHC）和蛋白质印迹（WB）评估LTA4H表达及其预后意义。通过慢病毒转导在ICC细胞系中对LTA4H进行遗传学调控。通过集落形成、实时细胞分析、划痕愈合和Transwell实验评估对增殖、迁移和侵袭的功能影响。通过将由pT3-EF1alpha-myr-AKT、pT3-EF1alpha-myr-NICD和pCMV-SB组成的质粒组合经水动力尾静脉注射，在小鼠中建立自发性ICC模型。通过RNA测序、代谢组学和WB研究机制。通过流式细胞术分析肿瘤免疫微环境。在体内和患者来源类器官中测试LTA4H特异性抑制剂LYS006的治疗效果。
结果：LTA4H在ICC组织中显著过表达，并与患者生存不良相关。LTA4H过表达在体外增强了ICC细胞的增殖、迁移和侵袭，并在体内加速了肿瘤进展。相反，敲低LTA4H抑制了这些恶性表型。机制上，LTA4H激活mTOR信号通路并在肿瘤微环境中诱导T细胞耗竭。使用LYS006对LTA4H进行治疗性抑制在小鼠模型和类器官中显著抑制了肿瘤生长。
结论：我们的研究将LTA4H确定为ICC中一种新的癌蛋白，它通过激活mTOR通路并借助T细胞耗竭营造免疫抑制微环境来驱动肿瘤进展。靶向LTA4H代表了ICC一种有前景的治疗策略。
临床意义：这项工作揭示了LTA4H在ICC中的双重促肿瘤功能，并为靶向LTA4H（可能单独使用或与免疫治疗联合）治疗这一致命疾病提供了有力依据。
查看英文原文 English abstract
Introduction: Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive liver cancer with a poor prognosis. Immune evasion plays a critical role in ICC progression. Leukotriene A4 hydrolase (LTA4H), a key enzyme in eicosanoid metabolism, is overexpressed in multiple cancer types; however, its role and mechanism in ICC remain entirely unexplored.
Methods: LTA4H expression and its prognostic significance were assessed in two independent ICC cohorts (n=130) and cell lines using bioinformatics, immunohistochemistry (IHC), and western blot (WB). LTA4H was genetically modulated in ICC cell lines via lentiviral transduction. Functional impacts on proliferation, migration, and invasion were evaluated by colony formation, real-time cellular analysis, wound healing, and Transwell assays. Spontaneous ICC was modeled in mice via hydrodynamic tail vein injection of a plasmid combination comprising pT3-EF1alpha-myr-AKT, pT3-EF1alpha-myr-NICD, and pCMV-SB. Mechanistic insights were investigated through RNA sequencing, metabolomics, and WB. Tumor immune microenvironment was profiled by flow cytometry. The therapeutic efficacy of the LTA4H-specific inhibitor LYS006 was tested in vivo and in patient-derived organoids.
Results: LTA4H was significantly overexpressed in ICC tissues and correlated with poor patient survival. LTA4H overexpression enhanced ICC cell proliferation, migration, and invasion in vitro, and accelerated tumor progression in vivo. Conversely, LTA4H knockdown suppressed these malignant phenotypes. Mechanistically, LTA4H activated the mTOR signaling pathway and induced T-cell exhaustion in the tumor microenvironment. Therapeutic inhibition of LTA4H with LYS006 significantly suppressed tumor growth in mouse models and organoids.
Conclusions: Our study identifies LTA4H as a novel oncoprotein in ICC that drives tumor progression by activating the mTOR pathway and fostering an immunosuppressive microenvironment via T-cell exhaustion. Targeting LTA4H represents a promising therapeutic strategy for ICC.
Clinical Significance: This work unveils the dual pro-tumorigenic functions of LTA4H in ICC and provides a strong rationale for targeting LTA4H, potentially alone or in combination with immunotherapy, for the treatment of this lethal disease.
利益披露 Disclosure
G. Lin, None..
J. Wang, None..
Y. He, None..
F. Feng, None..
C. Zheng, None.