Chu Xiaojing, Zhang Yu, Cheng Sijin
Changping Laboratory, Beijing 102206, China.
Chin J Cancer Res. 2022 Dec 30;34(6):543-553. doi: 10.21147/j.issn.1000-9604.2022.06.01.
Tumor microenvironment (TME) is highly heterogeneous and composed of complex cellular components, including multiple kinds of immune cells. Among all immune cells in TME, tumor-infiltrating myeloid cells (TIMs) account for a large proportion and play roles as key regulators in a variety of functions, ranging from immune-mediated tumor killing to tumor immune evasion. Understanding the heterogeneity of TIMs will provide valuable insights for new therapeutic targeting of myeloid cells. Single-cell genomic technologies deciphering cell composition and gene expression at single-cell resolution have largely improved our understanding of the cellular heterogeneity of TIMs and highlighted several novel cell subtypes contributing to the variation of patient survival and treatment response. However, these cell subtypes were defined based on limited data without a concordant nomenclature, which makes it difficult to understand whether they exist in different studies. Thus, in this review, we comprehensively summarized the common agreements and current different opinions on the heterogeneity of TIMs gained from single-cell studies; evaluated the feasibility of current myeloid cell targets at single-cell level and proposed a uniform nomenclature for TIM subsets.
肿瘤微环境（TME）具有高度异质性，由复杂的细胞成分组成，包括多种免疫细胞。在TME中的所有免疫细胞中，肿瘤浸润性髓系细胞（TIMs）占很大比例，并在从免疫介导的肿瘤杀伤到肿瘤免疫逃逸等多种功能中作为关键调节因子发挥作用。了解TIMs的异质性将为针对髓系细胞的新治疗靶点提供有价值的见解。以单细胞分辨率解析细胞组成和基因表达的单细胞基因组技术在很大程度上提高了我们对TIMs细胞异质性的理解，并突出了几种导致患者生存和治疗反应差异的新型细胞亚型。然而，这些细胞亚型是基于有限的数据定义的，没有一致的命名法，这使得很难了解它们是否存在于不同的研究中。因此，在本综述中，我们全面总结了从单细胞研究中获得的关于TIMs异质性的共识和当前不同观点；评估了当前髓系细胞靶点在单细胞水平的可行性，并提出了TIM亚群的统一命名法。
