Fig. 4
From: Colitis-associated carcinogenesis: crosstalk between tumors, immune cells and gut microbiota
Intestinal flora affects tumor progression. In the presence of probiotics in the intestinal tract, NK cells and macrophages phagocytize the abnormal flora due to the normal state of the body's immune system. At the same time, the secretion of cytokines and chemokines inhibits the abnormal proliferation of intestinal epithelium. In CAC, E.coli and other harmful bacteria enter intestinal epithelial cells, regulate various immune cells, and activate tumor-associated transcription factors (such as TLR4, NF-κB and PI3K/AKT), thus aggravating the tumor progression