活性酸素種によるピルバートキナーゼM2の抑制は,細胞の抗酸化反応に寄与する
Dimitrios Anastasiou1, George Poulogiannis, John M Asara
1Beth Israel Deaconess Medical Center, Department of Medicine-Division of Signal Transduction, Boston, MA 02115, USA.
Science (New York, N.Y.)
|November 5, 2011
まとめ
癌細胞は,ピルーバートキナーゼM2 (PKM2) を用いて活性酸素種 (ROS) を制御する. 酸化したPKM2は,グルコースをペントースリン酸経路に誘導し,ROSの解毒と腫瘍形成を支援します.
科学分野:
- バイオケミストリー バイオケミストリー
- 癌生物学 癌生物学について
- 細胞代謝について
背景:
- 細胞内活性酸素種 (ROS) の濃度は,がん細胞の生存に極めて重要です.
- ピルバ酸キナーゼM2 (PKM2) は,がん細胞の代謝と増殖に重要な役割を果たしています.
研究 の 目的:
- ヒトの肺がん細胞における細胞内ROS濃度の調節におけるPKM2の役割を調査する.
- ROSがPKM2の活性に影響するメカニズムを決定する.
- ガン細胞生存と腫瘍形成に対するPKM2酸化抵抗の調節の影響を評価する.
主な方法:
- ヒトの肺がん細胞系を利用した.
- 細胞内ROSの急激な増加がPKM2活性に与える影響を研究した.
- PKM2.2でCys(358) の酸化を分析した.
- サイト・ダイレクト・ミュータゲネシスを用いて,酸化抵抗性PKM2変異体 (Cys(358) からSer(358) を生成した.
- 酸化ストレスに対する癌細胞の感受性を評価した.
- 異種移植のマウスモデルでの腫瘍形成の評価.
主要な成果:
- 細胞内ROSの急激な増加は,Cysの酸化を通じてPKM2を阻害した[358].
- ROSによるPKM2阻害は,グルコースの流れをペントースリン酸経路に誘導するために不可欠です.
- この代謝のシフトは,ROSの解毒の可能性を減少させます.
- 酸化抵抗性PKM2を持つ肺がん細胞は,酸化ストレスに対する感受性の増加を示した.
- 酸化抵抗性PKM2.2の細胞を使用した異種移植モデルでは,腫瘍形成の障害が観察されました.
結論:
- PKM2の調節特性により,がん細胞は酸化ストレスに耐えるようになります.
- PKM2酸化を調節することは,がん細胞を標的とする潜在的な治療戦略を提供します.
- PKM2の役割は増殖を超えて,酸化ストレス下でのがん細胞生存に貢献します.
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