Exploration of reciprocal interactions between gut microbiota and host microemvironment

• Project/Area Number: 19K24057
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0906:Surgery related to the biological and sensory functions and related fields
• Research Institution: Fukuoka Dental College
• Principal Investigator: Wada Hiroya 福岡歯科大学, 口腔歯学部, 臨床教授 (70851509)
• Project Period (FY): 2019-08-30 – 2024-03-31
• Project Status: Completed (Fiscal Year 2023)
• Budget Amount: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: メタゲノム解析 / 乳癌 / 腸内細菌 / 次世代シーケンサー / 腸内細菌叢

Outline of Research at the Start

メタゲノム解析（次世代シーケンサーを用いたゲノムDNAの解析）にて、実際の癌患者と健常人との腸内細菌叢の比較を行い、乳癌発症と関わる腸内細菌叢を検出し、その腸内細菌叢と乳癌サブタイプ、各癌患者の免疫環境、腫瘍内微小環境(免疫サブタイプ)、臨床病理学的事項の関連性を明らかにし、非消化器腫瘍と腸内細菌叢の関連性を結びつける新たな研究分野を提唱する。

Outline of Final Research Achievements

Gut microbial dysbiosis affects the occurrence of gastrointestinal diseases, such as inflammatory bowel diseases, and systemic autoimmune diseases, such as rheumatoid arthritis and multiple sclerosis. Here, we performed metagenomic analysis of breast cancer patients as a non-gastrointestinal tract cancer, which affects carcinogenesis, cancer promotion, tumor microenvironment, and host cancer immunological response, especially as compared with colon cancer patients, using the TCGA and BIC databases. As a result, the microbial flora in breast cancer patients differs from that in colon cancer patients. The high relative abundance of the Genus Bifidobacterium, which is thought to enhance T-cell response, and low relative abundance of Genus Prevotella, are correlated with better prognosis in breast cancer patients.

Academic Significance and Societal Importance of the Research Achievements

今回、我々の検討にて、乳癌患者に検出される細菌叢は大腸癌患者の細菌叢と異なっており、T細胞応答を増強すると考えられるBifidobacterium属の相対的高占有率及びPrevotella属の相対的低占有率と患者予後との相関が得られたこと及び各々の細菌属は他の細菌属とのネットワークを形成している事から、適切なprobiotics投与などによって、特にICI等の治療効果の増強やcancer promotionの抑制等に影響を及ぼし、乳癌患者の予後改善に寄与できる可能性が示唆されたことは意義深いと考える。

Research Products

• [Journal Article] Use of Insoluble Dietary Fiber and Probiotics for Bowel Preparation Before Colonoscopy: A Prospective Study (2022)
  • Author(s): Kudou Kensuke、Kimura Koich、Tsutsumi Ryosuke、Hashimoto Naotaka、Wada Hiroya、Ikeda Tetsuo
  • Journal Title: Surgical Laparoscopy, Endoscopy & Percutaneous Techniques Volume: 32 Issue: 2 Pages: 153-158
  • DOI: 10.1097/sle.0000000000000995
  • Peer Reviewed / Open Access