RESUMO
Hundreds of millions of gut microbiota, intestinal epithelial cells and immune cells together constitute a unique gastrointestinal microenvironment. In intestine, the balance between proinflammatory and repair signals of the immune system is essential for the maintenance of intestinal homeostasis. A variety of pattern recognition receptors, including Toll-like receptors (TLR), constitute the body’s innate immune defense against pathogens by identifying pathogenassociated molecular patterns and damage-associated molecular patterns. Many investigations support that TLR signaling pathway plays an important role in the genesis and development of intestinal malignancies. Intestinal flora-TLR signaling pathway-inflammation and cancer cascade reaction are considered as the possible pathogenesis of colorectal cancer. The structure and function of TLR family, TLR signaling pathway and its role in the genesis and development of colorectal cancer will be summarized in this review.