Prevalence of colibactin positive E. colin in colorectal cancer patients

2016 Fiscal Year Final Research Report

• Project/Area Number: 26460962
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Gastroenterology
• Research Institution: The University of Tokyo
• Principal Investigator: Yoshida Shuntaro 東京大学, 医学部附属病院, 助教 (70598713)
• Research Collaborator: OTA YUMIKO 東京大学, 医学部附属病院, 特任臨床医 ; SHIMPOH TAKAYUKI 東京大学, 医学部附属病院, 特任臨床医
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 大腸癌 / 大腸菌 / スクリーニング

Outline of Final Research Achievements

Colorectal cancer (CRC) development is considered to be affected by luminal microbiota, and colibactin positive Escherichia coli (E. coli) is shown to be one of those microorganism from foreign studies. We examined the prevalence of colibactin positive bacteria in colonic lavage of CRC patients in Japan. We established DNA preparation method from colonic lavage and qualitative, quantitative detection method of colibactin (clbB) gene. Prevalence of colibactin positive bacteria was 43% in CRC cases, and 51% in control cases, providing no significant differences. In subgroup analysis of CRC cases, colibactin negative bacteria was associated with wild type k-ras gene, but not other clinicopathological factors. These results suggest that CRC in Japanese, especially k-ras wild CRC, may have different pathogenesis from CRC in other countries. Factors other than colibactin positive bacteria may be associated with the development of CRC in Japan.

Free Research Field

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