Development of a colorectal cancer diagnostic model and dietary risk assessment through gut microbiome analysis

• Published in: Experimental & molecular medicine Vol. 51; no. 10; pp. 1 - 15
• Main Authors: Yang, Jinho, McDowell, Andrea, Kim, Eun Kyoung, Seo, Hochan, Lee, Won Hee, Moon, Chang-Mo, Kym, Sung-Min, Lee, Dong Ho, Park, Young Soo, Jee, Young-Koo, Kim, Yoon-Keun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03.10.2019; Springer Nature B.V; 생화학분자생물학회
• Subjects: 45/23; 692/53/2421; 692/699/67/2322; Aged; Animals; Bacteria - classification; Bacteria - genetics; Biomedical and Life Sciences; Biomedicine; Cancer; Cholesterol; Cholesterol - genetics; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - diagnosis; Colorectal Neoplasms - genetics; Colorectal Neoplasms - microbiology; Colorectal Neoplasms - pathology; Diet; Diet, High-Fat - adverse effects; Dietary intake; Digestive system; Feces - microbiology; Female; Gastrointestinal Microbiome - genetics; Gut microbiota; High cholesterol diet; High fat diet; Humans; Intestinal microflora; Male; Meat; Medical Biochemistry; Metagenome - genetics; Mice; Microbiomes; Microbiota; Microbiota - genetics; Middle Aged; Molecular Medicine; Prediction models; Public health; Risk Assessment; Stem Cells; Westernization; 생화학
• DOI: 10.1038/s12276-019-0313-4
• ISSN: 1226-3613; 2092-6413

Colorectal cancer (CRC) is the third most common form of cancer and poses a critical public health threat due to the global spread of westernized diets high in meat, cholesterol, and fat. Although the link between diet and colorectal cancer has been well established, the mediating role of the gut microbiota remains elusive. In this study, we sought to elucidate the connection between the gut microbiota, diet, and CRC through metagenomic analysis of bacteria isolated from the stool of CRC ( n  = 89) and healthy ( n  = 161) subjects. This analysis yielded a dozen genera that were significantly altered in CRC patients, including increased Bacteroides , Fusobacterium , Dorea , and Porphyromonas prevalence and diminished Pseudomonas , Prevotella , Acinetobacter , and Catenibacterium carriage. Based on these altered genera, we developed two novel CRC diagnostic models through stepwise selection and a simplified model using two increased and two decreased genera. As both models yielded strong AUC values above 0.8, the simplified model was applied to assess diet-based CRC risk in mice. Mice fed a westernized high-fat diet (HFD) showed greater CRC risk than mice fed a regular chow diet. Furthermore, we found that nonglutinous rice, glutinous rice, and sorghum consumption reduced CRC risk in HFD-fed mice. Collectively, these findings support the critical mediating role of the gut microbiota in diet-induced CRC risk as well as the potential of dietary grain intake to reduce microbiota-associated CRC risk. Further study is required to validate the diagnostic prediction models developed in this study as well as the preventive potential of grain consumption to reduce CRC risk. Colorectal cancer: Factors influencing cancer risk Tracing biomarkers of gut bacteria sheds light on how diet can affect gut composition and the risk of developing colorectal cancer (CRC). CRC is linked to diet, and scientists are examining how diet-associated changes in the gut microbiome may influence cancer risk. Yoon-Keun Kim, MD Healthcare Inc., Seoul, and Young-Koo Jee, Dankook University College of Medicine, Cheonan, South Korea, and co-workers analyzed bacterial populations in fecal samples from 89 CRC patients and 161 healthy controls. They found significant differences between patients and controls in 16 bacterial genera, these differences being potential biomarkers in diagnostic models for assessing CRC risk. The researchers used the models to determine CRC risk in mice fed diets, and found that the predicted risk was considerably reduced in mice on grain diets, especially rice or sorghum, compared to high fat diets.