Investigating intestinal environments as risks for pancreatico-biliary cancers

Research Project

Project/Area Number	17K09462
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Gastroenterology
Research Institution	Okayama University
Principal Investigator	Takaki Akinobu 岡山大学, 医歯薬学総合研究科, 准教授 (80359885)
Co-Investigator(Kenkyū-buntansha)	森田英利岡山大学, 環境生命科学研究科, 教授 (70257294) 松本和幸岡山大学, 大学病院, 助教 (40795027) 高原政宏岡山大学, 大学病院, 医員 (80738427)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000) Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000) Fiscal Year 2018: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000) Fiscal Year 2017: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Keywords	膵癌 / 腸内細菌叢 / 腸内環境 / 腸内細菌叢解析 / 細菌 / 内科
Outline of Final Research Achievements	Aim: The aim of this study was to investigate microbiome analysis of the stool and saliva in pancreatic cancer patients and high risk patients defining the high risk microbiome for the prevention of the pancreatic cancer development. Methods: We collected 24 cases of pancreatic cancer (PK), 16 cases of intraductal papillary mucinous neoplasm (IPMN). Results: From the stool analysis, the diversity of the PK showed low and there was a reduced genus, Lachnospira, which has been reported to be favorable for guarding patients from side effects under chemotherapy. There was another genus which showed increased frequency in PK group, Mogibacterium, which is known as risk bacteria for colon cancer development. From the saliva analysis, a gingival cancer risk periodontitis related bacteria, Atopobium genus was predominant. Conclusion: The risk bacteria genus were determined from both saliva and stool. To control these microbiome is the next step to decrease the development of PK.
Academic Significance and Societal Importance of the Research Achievements	膵癌と膵癌リスクを有するIPMNの間で腸内細菌叢解析を比較、膵癌では細菌叢の多様性が低下、抗がん剤治療の副作用を生じにくい可能性がある菌の減少が明らかになった。この菌は食事中の繊維摂取により増加する可能性がある事から、膵癌発症後でも繊維成分の食事を増やすことで、経過を改善できる可能性があると考えられた。膵癌で、大腸癌でも発癌リスクの可能性が報告されている菌が増加しており、予防的治療ターゲットになる可能性がある。口腔内の細菌叢解析よりは、膵癌で歯周病菌の中でも口腔癌のリスクであると報告されている菌が増加、歯周病対策などにより膵癌リスクを低下させることが出来る可能性があることが明らかになった。