Research groups such as Osaka University, Tokyo Institute of Technology, Tokyo University, and Keio University conducted metagenome analysis and metabolome analysis using stools on 616 patients who underwent colonoscopy (colonoscope). We have succeeded in identifying bacteria and metabolites characteristic of the stool of patients with multiple polyps (adenomas) and intramucosal cancer, which are precancerous lesions.
Colorectal cancer, which has overtaken gastric cancer and has become the most common cancer in Japan, progresses to advanced cancer via colorectal polyps (adenomas) and intramucosal cancer.So far, some bacteria characteristic of advanced colorectal cancer have been identified, but for colorectal polyps (adenomas) and intramucosal cancer, which are the stages before advanced cancer, related bacteria and metabolites have been identified. Was not known.
This time, the research group investigated the characteristics of the intestinal environment at each stage of cancer by making full use of metagenomic analysis (decoding of DNA genome sequence) and metabolome analysis (component analysis of metabolites).Then, it was found that even with the same colorectal cancer, the intestinal bacteria and intestinal metabolites that increase or decrease in the stool differ greatly depending on the stage of cancer progression.For example, Atopobium parvulum and Actinomyces odontolyticus have been identified as bacteria that are elevated only in the stage of multiple polyps (adenomas) and intramucosal cancers. It was strongly suggested that bacteria are associated with the early onset of colorectal cancer.
This finding, which clarified the intestinal environment related to colorectal cancer carcinogenesis, is expected to lead to early diagnosis and prevention of colorectal cancer, and application to "preemptive medicine" that treats colorectal cancer before it develops. NS.
Paper information:[Nature Medicine] Metagenomic and metabolomic analyzes reveal distinct stage-specific phenotypes of the gut microbiota in colorectal cancer