腸内炎症は,微生物群のがん誘発活性を標的とする
Janelle C Arthur1, Ernesto Perez-Chanona, Marcus Mühlbauer
1Department of Medicine, Pharmacology and Immunology-Microbiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
まとめ
炎症は腸内微生物を変化させることで結腸直腸がん (CRC) を促進する. 遺伝子毒性の島を運ぶ特定の細菌である大腸菌 (Escherichia coli) は,感受性の高いマウスの腫瘍増殖を促し,CRCの予防のための微生物標的を強調しています.
科学分野:
- 微生物学 微生物学とは
- 腫瘍学 腫瘍学
- 胃腸内科 胃腸内科
背景:
- 炎症は,結腸直腸がん (CRC) の発症の既知の原動力である.
- 炎症に関連したCRCにおける腸内微生物群の役割は,ますます認識されています.
研究 の 目的:
- 腸内微生物群の炎症誘発による変化が結腸直腸癌の進行にどのように影響するかを調査する.
- 大腸炎モデルの腫瘍発生に寄与する特定の微生物要因を特定する.
主な方法:
- 腸炎に敏感なインターリューキン-10欠乏症 (Il10(-/-)) のマウスを使用した.
- CRCを誘発するためにアゾキシメタン (AOM) を投与し,Escherichia coli NC101でモノコロニゼーションを行った.
- 腸内微生物の組成を分析するために高通量配列を解析した.
- ポリケチド合成酵素の遺伝子毒性島の役割を評価するために,pks欠乏のE. coli菌株を生成しました.
主要な成果:
- 炎症による腸内微生物の組成の変化は,Il10(-/-) のマウスで観察されました.
- E. coli NC101によるモノコロニゼーションは,AOMで治療されたIl10(-/-) マウスの侵入性がんを促した.
- E. coliからpks遺伝子毒性の島を除去すると,炎症に影響を与えることなく,腫瘍の多様性と侵入を減少させました.
- pks(+) E. coliはヒトの炎症性腸疾患およびCRC患者で発見されました.
結論:
- 大腸炎は,微生物の組成を変更し,遺伝子毒性細菌を拡大することにより,CRC腫瘍発生を促進します.
- E. coliのpks遺伝子毒性の島は,CRCの進行に寄与する.
- 遺伝子毒性細菌をターゲットにすることで,CRCを予防または治療するための戦略を提供することができます.
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