[Effect of macrophages on ulcerative colitis-associated carcinogenesis].

Ulcerative colitis is a non-specific colorectal inflammation of unknown causes. It is now known to complicate the dangers of colorectal cancer more than was previously thought. Macrophages are an important part of immune system and play a positive role in immune reaction. But it has been shown that the phenotype and the function of macrophages change in the tumor microenvironment. Through their interaction with colorectal cancer cells and by releasing large quantities of cytokines, macrophages promote colorectal cancer cells by inhibiting angiogenesis and inhibit apoptosis. But the macrophages are also affected by cancer, interact with other inflammatory cells, and become immune suppressed. Thus the changes of macrophages are inseparable with colitis-associated colorectal carcinogenesis.