AMPKはNADPHホメオスタシスを調節し,エネルギーストレスの間に腫瘍細胞の生存を促進します
Sang-Min Jeon1, Navdeep S Chandel, Nissim Hay
1Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
Nature
|June 5, 2012
まとめ
AMPKの活性化は,NADPHレベルを調節することによって,がん細胞が代謝ストレスから生き残るのを助けます. この経路は,腫瘍の成長とエネルギー制限の条件下での生存に不可欠です.
科学分野:
- 細胞生物学 細胞生物学
- メタボリック・レギュレーション
- がん研究 がん研究
背景:
- メタボリックストレスは固体腫瘍の成長に不可欠ですが,細胞死と生存のメカニズムは不明です.
- 肝臓キナーゼB1 (LKB1) -AMP活性化タンパク質キナーゼ (AMPK) 経路は,代謝適応の鍵となる.
- LKB1欠乏またはAMPK欠乏細胞は,腫瘍原性変異と腫瘍発生に対する抵抗を示します.
研究 の 目的:
- AMPKが腫瘍細胞の代謝適応を促進するメカニズムを解明する.
- 代謝ストレス下での細胞生存におけるAMPKの役割を調査する.
- 癌細胞生存のためのNADPH維持におけるAMPKの機能を理解する.
主な方法:
- エネルギーストレスのときのAMPK活性化が調査されました.
- NADPH生成と消費経路を分析した.
- AMPK媒介による効果におけるアセチル-CoAカルボキシラーゼ (ACC1とACC2) の役割を調べました.
- 遺伝子ノックダウンと活性化実験を活用した.
- 定着点独立の成長と in vivo 固体腫瘍形成を評価した.
主要な成果:
- AMPKの活性化は,エネルギーストレス下での酸化還元調節による細胞生存を延長します.
- AMPKは,ペントースリン酸経路が損なわれるときに,NADPHを維持するための代替経路を誘導します.
- AMPKはACC1とACC2を阻害し,NADPHの消費を減らし,その生成を増加させます.
- ACC1/ACC2のノックダウンはAMPKの活性化を模倣し,腫瘍の成長を促します.
- ACC1/ACC2の活性化は,腫瘍の成長を弱める.
結論:
- AMPKは,NADPHレベルを維持することによって,エネルギーストレス下での癌細胞生存に不可欠です.
- AMPKの役割は,ATPホメオスタシスを超えて,不可欠なNADPH維持を含みます.
- AMPK-ACC経路をターゲットにすることで,がんに対する治療戦略を提供することができる.
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