Gastrointestinal Microbiota and Colon Cancer

The human gut microbiota plays a major role in the development and maintenance of good health. Many recent studies have attempted to define links between microbiota residents, their function and the development of colorectal cancer (CRC). Gut microbiota drive the development of inflammation within the colon and such inflammation is implicated in colonic neoplastic development. Although the precise mechanisms through which the microbiota is involved in cancer development remain elusive, the message is clear: the microbiota contributes to cancer risk by influencing a number of key host processes. It is also recognized that we have the ability to influence the role of the gut microbiota by considering our nutritional intake. We have always known that ‘we are what we eat' but it is also true that ‘they (our gut microbiota) are what we eat'. We therefore have a huge opportunity to positively influence our health through microbial manipulation. There is now a clear need to move past defining the constituents of the gastrointestinal microbiota and to focus more on understanding the functional capabilities of the resident microbial community and how this impacts on host health. One such emerging concept is the development of microbial biofilms which can form in the gut in conjunction with CRC tissue. By better understanding of the interaction between the host and its resident microbiota, in the context of health and cancer development, we will open new therapeutic and diagnostic opportunities for reducing the CRC global health burden.