Role of Tumor Associated Macrophages in Chemotherapy Resistance and Intervention with Traditional Chinese Medicine： A Review / 中国实验方剂学杂志

ABSTRACT

The tumor incidence goes up with every passing year. Chemotherapy， as one of the main treatment methods， is faced with a major challenge of drug resistance in clinical practice. Tumor-associated macrophages （TAMs） are the key factors inducing chemotherapy resistance of tumors. TAMs are inflammatory cells with the largest number in the tumor microenvironment， which are widely distributed in such epithelial tissues as large intestine and stomach in the immune environment and closely associated with multiple common cancers like breast cancer and colorectal cancer. TAMs can be divided into two phenotypes， with M2-polarized TAMs into the tumor-promoting phenotype that affects the oncogenesis and progression and promotes drug resistance via immune escape， angiogenesis and other ways. At the same time， the frequently utilized chemotherapeutic agents will increase the recruitment of TAMs and trigger the secretion of cytokines， leading to the excessive polarization of macrophages to M2 type， followed by tumor drug resistance. The molecular mechanism of chemotherapy resistance is complex， which is becoming an urgent problem in the field of chemotherapy. Traditional Chinese medicine （TCM） has exhibited unique advantages in resisting tumor drug resistance. It has been proved efficient and safe in improving tumor microenvironment and regulating TAMs by acting on multiple targets via multiple ways， thus adjusting tumor progression and improving drug resistance. Based on related articles published in recent years， this paper reviewed the drug resistance-promoting effect of TAMs via regulating the immune microenvironment and interacting with tumor stem cells and the driving effect of chemotherapeutic agents on drug resistance to figure out the role of TAMs in chemotherapy resistance. Besides， it summarized the mechanisms of TCM in regulating related cytokines， proteins， activity， and the polarization direction of TAMs to expound the effective components of TCM in the intervention of drug resistance. The aim of this paper was to provide reference for further research on the biological mechanism of chemotherapy resistance and its targeted intervention with TCM.