Research progress of tumor microenvironment and tumor-associated macrophages.

Cancer is a health issue causing utmost concern and continuing to be one of the leading causes of mortality worldwide. Effective tumor eradication methods that will improve the prognosis and prolong human life are an important topic in modern medicine. Increasing amounts of evidence indicate that the tumor microenvironment plays a significant role in tumor development and migration. Macrophages are important immune cells that commonly infiltrate the tumor microenvironment. Several studies found that macrophages play different roles in the process of cancer development. This article focuses on the tumor microenvironment and the generation, classification, and function of tumor-associated macrophages as well as their significance for tumor immunotherapy and other aspects, it summarizes nearly 10 years of tumor microenvironment and tumor-associated macrophage research, providing a novel insight for tumor immunotherapy.