PKCεは,核内のATF2の腫瘍性機能を促進し,ミトコンドリアにおけるそのアポプトティック機能を阻害する
Eric Lau1, Harriet Kluger, Tal Varsano
1Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
Cell
|February 7, 2012
まとめ
転写因子ATF2は,ミトコンドリアに局所化することによって,皮膚がんにおける腫瘍抑制剤として作用する. しかし,メラノーマのPKCε濃度の高さは,この機能を阻害し,がんの進行を促進します.
科学分野:
- 細胞生物学 細胞生物学
- 分子腫瘍学 分子腫瘍学
- がん研究 がん研究
背景:
- 転写因子ATF2は,メラノーマの腫瘍遺伝子として,非悪性皮膚がんの腫瘍抑制剤として作用し,二重の役割を果たしています.
- ATF2の異なる機能を制御するメカニズムを理解することは,標的型がん治療の開発に不可欠です.
研究 の 目的:
- ATF2のサブセルラー局在が,その腫瘍原性または腫瘍抑制活性にどのように影響するか解明する.
- ATF2の局所化と機能を調節するタンパク質キナーゼCエプシロン (PKCε) の役割を調査する.
主な方法:
- 遺伝子毒性ストレスへの反応としてATF2の局所化を研究した.
- ATF2とPKCεの相互作用を調べました.
- ATF2ミトコンドリアの局所化がミトコンドリアの透過性とアポトーシスに与える影響を分析した.
- 関連PKCεレベルとATF2機能,およびメラノーマのサンプルにおける患者の予後.
主要な成果:
- ATF2の腫瘍抑制機能は,PKCεによって調節されるそのミトコンドリアの局所に依存する.
- 遺伝子毒性ストレスは,ミトコンドリアへのATF2核輸出を促進し,そこでHK1-VDAC1複合体を混乱させ,ミトコンドリアの透過性とアポトーシスを増加させます.
- メラノーマ細胞のPKCε濃度の高さは,ATF2の核輸出を阻害し,その腫瘍抑制機能を阻害し,アポトーシスに対する耐性を促進する.
- メラノーマ腫瘍におけるPKCε濃度の上昇は,患者の予後不良と相関しています.
結論:
- サブセルラー局所化は,ATF2の腫瘍性または腫瘍抑制機能の重要な決定因子です.
- PKCεは,ATF2の細胞運命を調節し,がんの発症に及ぼす影響において重要な役割を果たしています.
- ATF2-PKCε軸をターゲットにすることで,メラノーマに対する新しい治療戦略を提供することができる.
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