Research Progress of Nano-drug Delivery System Targeting Tumor-associated Macrophage in Cancer Treatment

Tumor-associated macrophages(TAMs), abundantly infiltrated in the tumor microenvironment, have a significant influence on tumor metastasis, angiogenesis and immune escape. Therefore, TAMs-targeted immunotherapy has become a hot point in the field of cancer treatment. However, most of the conventional TAMs-targeted agents may cause serious adverse effects, such as short retention time, poor drug enrichment and drug-resistance. In order to overcome these shortcomings, nanobiotechnology has attracted considerable attention. More recently, a series of important progress for nanomedicine has been achieved in the area of drug delivery and diagnostic imaging, because of their special physical and chemical properties. Hence, the TAMs-targeted nanomedicine delivery system provides new ideas for tumor immunotherapy. This paper reviews the role of TAMs in tumor microenvironment, the tumor-promoting mechanism, and introduces the research progress of nanomedicine in TAMs polarization, nanodrug delivery, TAMs-targeted imaging and preventing the TAMs recruitment, so as to provide reference for the application of nanotechnology in tumor immunotherapy.