Research Progress of Different Subtypes of Myeloid-derived Suppressor Cells and Traditional Chinese Medicine Regulation Effect in Tumor Microenvironment / 中国实验方剂学杂志

ABSTRACT

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.