# Research Advances on the Immune Evasion Mechanisms of Disseminated Tumor Cells and Their Roles in Cancer Metastasis

## TL;DR

This paper reviews how disseminated tumor cells evade the immune system to promote cancer metastasis and explores new insights combining traditional Chinese medicine theories.

## Contribution

The paper innovatively integrates traditional Chinese medicine concepts with modern immunology to explain DTCs' immune evasion.

## Key findings

- DTCs use antigen presentation defects to avoid immune detection.
- Immunosuppressive cells like Tregs and MDSCs help DTCs create a protective microenvironment.
- Metabolic reprogramming in DTCs weakens immune cell function.

## Abstract

肿瘤转移是导致癌症患者死亡的首要原因，而播散肿瘤细胞（disseminated tumor cells, DTCs）作为转移级联反应中的关键“种子”，其命运直接决定了转移的成败。DTCs从原发灶脱落并定殖于远处靶器官后，常进入一种长期休眠状态，随后通过复杂的免疫逃逸机制突破免疫监视，从休眠态激活为增殖态，最终形成临床可评估的转移灶。深入理解DTCs的免疫逃逸机制对于揭示肿瘤转移的本质和开发有效的抗转移策略至关重要。本文系统综述了DTCs免疫逃逸机制的最新研究进展，重点围绕三大核心机制展开：抗原呈递缺陷、免疫抑制微环境的形成以及代谢重编程介导的免疫抑制。具体而言，DTCs通过下调主要组织相容性复合体I类（major histocompatibility complex class-I, MHC-I）分子表达实现“免疫隐身”；主动招募调节性T细胞（regulatory T cells, Tregs）、髓源性抑制细胞（myeloid-derived suppressor cells, MDSCs）等免疫抑制性细胞，构建局部“防护盾”；并通过重塑糖、氨基酸及脂质代谢，从能量与物质层面削弱效应免疫细胞功能。在此基础上，本文创新性地结合中医“正虚伏毒”与“转移态”理论，阐释机体正气盛衰与DTCs休眠-觉醒转换之间的动态病机关系，为从整体调控角度认识转移过程提供了新视角。最后，文章展望了针对DTCs免疫逃逸的多靶点联合治疗策略，以及单细胞测序、空间转录组等新技术在该领域的应用前景，以期为未来抗转移研究的深入与临床转化提供重要参考。

Major immunosuppressive cells in the DTCs microenvironment: their roles and key effector molecules