Gut Microbiota and Colorectal Cancer.

BACKGROUND: Colorectal cancer (CRC) is a leading cause of cancer-related mortality worldwide whose incidence has increased rapidly in recent years. There is growing evidence that the complex gut microbiota community plays an important role in the development of intestinal tumorigenesis.

SUMMARY: This review aimed to explore the correlation between gut microbiota and CRC as well as to identify the pathogens and their metabolites that affect CRC and the potential models of gut microbiota action. It promotes our understanding of the correlation between gut microbiota and CRC.

KEY MESSAGE: Our knowledge of the risk factors associated with gut microbiota for CRC development, as well as of the mechanism how intestinal bacteria act on colorectal tumorigenesis, has improved, leading to a better understanding of the correlation between gut microbiota and CRC.

PRACTICAL IMPLICATIONS: The intestinal microbiota community has a close relationship with CRC by influencing the mechanism of the body and by regulating the physiological function of the colorectum and even the entire digestive system. Gut microbiota have been linked to CRC based upon their toxic and genotoxic metabolites production by fermentation of dietary ingredients. These metabolites could bind specific intestinal cell surface receptors and subsequently affect intracellular signal transduction. The mechanisms by which gut microbiota affect CRC development include the 'Alpha-bug' model, the 'driver-passenger' model and the 'intestinal microbiota adaptions' model. This review promotes our understanding of the correlation between gut microbiota and CRC.