Bacteroides

Bacteria

Biology

Colorectal cancer

Fusobacterium nucleatum

Bacteroides fragilis

Porphyromonas gingivalis

Fusobacterium

Environmental health

Immunology

Genetics

Microbiome

Bioinformatics

Immune system

Antibiotics

Microbiology

Population

Internal medicine

Periodontitis

Gut flora

Medicine

Carcinogenesis

Cancer

Nature Reviews Gastroenterology & Hepatology

Colorectal cancer (CRC) accounts for about 10% of all new cancer cases globally. Located at close proximity to the colorectal epithelium, the gut microbiota comprises a large population of microorganisms that interact with host cells to regulate many physiological processes, such as energy harvest, metabolism and immune response. Sequencing studies have revealed microbial compositional and ecological changes in patients with CRC, whereas functional studies in animal models have pinpointed the roles of several bacteria in colorectal carcinogenesis, including Fusobacterium nucleatum and certain strains of Escherichia coli and Bacteroides fragilis. These findings give new opportunities to take advantage of our knowledge on the gut microbiota for clinical applications, such as gut microbiota analysis as screening, prognostic or predictive biomarkers, or modulating microorganisms to prevent cancer, augment therapies and reduce adverse effects of treatment. This Review aims to provide an overview and discussion of the gut microbiota in colorectal neoplasia, including relevant mechanisms in microbiota-related carcinogenesis, the potential of utilizing the microbiota as CRC biomarkers, and the prospect for modulating the microbiota for CRC prevention or treatment. These scientific findings will pave the way to clinically translate the use of gut microbiota for CRC in the near future. Colorectal cancer (CRC) is one of the most common cancers worldwide. This Review describes the role of microorganisms in colorectal carcinogenesis, and the potential clinical translation of the gut microbiota as a biomarker for CRC diagnosis and prognosis, and as an approach for disease prevention and to improve therapy.

Gut microbiota in colorectal cancer: mechanisms of action and clinical applications