ARG1 and malignant colon neoplasm: Studies have shown that the proportion of M2-like macrophages, which are characterized by CD206 and Arg-1 expression, is increased in the colon cancer microenvironment, while the proportion of M1-like macrophages, which are characterized by CD86 and iNOS expression, is decreased in the colon cancer microenvironment, leading to immunosuppressive and tumor-promoting effects in colon cancer [21, 22].