肿瘤微环境中不同亚型的髓源抑制性细胞及中医药对其调控作用的研究进展

肿瘤的诊疗手段不断提高,但是癌症的死亡率仍然是居高不下,目前学术界已意识到现有治疗思路的不足,逐渐将癌细胞"赶尽杀绝"的观念向与其"和平共处"转变,"带瘤生存"成为肿瘤学术界普遍接受的理念。肿瘤微环境是肿瘤细胞赖以生存和发展的场所,故调控肿瘤微环境,成为了肿瘤治疗的重要新策略。髓源抑制性细胞(MDSCs)是一群在肿瘤微环境中对T细胞具有免疫抑制特性的异质性细胞群体,在肿瘤免疫逃逸中发挥重要作用,如今以肿瘤微环境中的MDSCs为作用靶点亦为肿瘤治疗提供新思路。又由于MDSCs细胞亚群与嗜中性粒细胞及单核细胞的表型特征相似而主要可分为粒细胞样-髓源抑制性细胞(G-MDSCs)和单核细胞样-髓源抑制性细胞(M-MDSCs)两大亚型,但此2种亚型是如何区别于嗜中性粒细胞和单核细胞,不同亚型的MDSCs的功能特征又有何不一样,他们又是如何通过不同途径来累积、分化以及发挥免疫抑制作用,中医药素来擅长调控机体微环境,越来越多的研究显示中医复方及其活性成分能够有效抑制MDSCs的募集、扩增及活化,为中医药靶向肿瘤微环境中的MDSCs提供科学依据,但其具体通过何种途径调控何种亚型的MDSCs,目前尚缺乏较深入的机制探究。以往的文献综述的研究重点在MDSCs整体层面,该文将立足于MDSCs的具体亚型,并力求明确其生物学特性,以便在肿瘤微环境中实现更精确的靶向治疗。

Research Progress of Different Subtypes of Myeloid-derived Suppressor Cells and Traditional Chinese Medicine Regulation Effect in Tumor Microenvironment

The diagnosis and treatment methods for cancer are being improved continually, but the mortality of cancer still remains high. At present, the academic circle has realized deficiency of existing treatment ideas, and the concept of cancer cells has been gradually changed from "extremely extinct" to "peaceful coexistence". The concept of "survival with tumors" is universally accepted in the cancer academia. The tumor microenvironment is the place where tumor cells survive and develop. Therefore, regulation of the tumor microenvironment has become an important new strategy for tumor treatment. Myeloid-derived suppressor cells (MDSCs) are a group of heterogeneous cells that have immunosuppressive properties on T cells in the tumor microenvironment and play an important role in tumor immune escape. Now, therapy with MDSCs in the tumor microenvironment as the treatment targets also provides new ideas for the tumor treatment. As MDSCs subpopulations are similar with neutrophils and monocytes, they can be divided into two major subtypes:granulocyte-like myeloid-derived suppressor cells (G-MDSCs) and monocyte-myeloid-derived suppressor cells(M-MDSCs). But how to differ these two subtypes from neutrophils and monocytes. What are the differences in the functional characteristics of different subtypes of MDSCs. How do they accumulate, differentiate, and exert immunosuppressive effects through different pathways. Traditional Chinese medicine(TCM) has always been good at modulating the body''s microenvironment. More and more researches have shown that, the recruitment, amplification and activation of MDSCs can be effectively inhibited by TCM compound and its active ingredients, providing scientific basis for Chinese medicine targeting MDSCs in the tumor microenvironment. However, which specific pathways could regulate G-MDSCs or M-MDSCs is still in need of further studies. Most previous literature focus on the overall level of MDSCs, while the this paper would be based on the specific subpopulations of MDSCs to clarify the biological characteristics of these two subtypes of MDSCs, so as to achieve more precise targeted therapy in the tumor microenvironment.