腫瘍遺伝子の誘発性衰老は,DNA超複製によって引き起こされるDNA損傷反応である
Raffaella Di Micco1, Marzia Fumagalli, Angelo Cicalese
1IFOM Foundation-FIRC Institute of Molecular Oncology Foundation, 20139 Milan, Italy.
Nature
|December 1, 2006
まとめ
腫瘍遺伝子の活性化により,DNA複製ストレスが引き起こされ,DNA損傷反応 (DDR) が活性化されます. このDDRの強制は,腫瘍遺伝子の誘発性衰老 (OIS) に繋がり,細胞の変容と早期の腫瘍発生を防ぐ.
科学分野:
- 細胞生物学 細胞生物学
- がん研究 がん研究
- 遺伝学 遺伝学とは
背景:
- 早期の腫瘍形成には,DNA損傷反応 (DDR) が含まれる.
- 腫瘍遺伝子の活性化は細胞老化を誘発し,増殖を制限する.
- DDRと腫瘍遺伝子の誘発性衰老 (OIS) の因果関係は不明である.
研究 の 目的:
- DDRのアクティベーションとOISの因果関係を調査する.
- DDRがOISの前提条件であるかどうかを判断する.
- OISにおけるDNA複製の役割を明らかにする.
主な方法:
- 人間の細胞における活性化されたH-RasV12腫瘍遺伝子の発現.
- DDRの実験的な無効化.
- In vivo DNAのラベル付けと分子DNAの理.
- DNA複製と起源発火の分析.
主要な成果:
- OISは,腫瘍遺伝子の発現に続く強力なDDR活性化の結果である.
- DDRの無効化は,OISを無効化し,細胞の変容を促進します.
- 衰老細胞は部分的に複製されたDNAと複数の起源発火を示します.
- 腫瘍遺伝子の活性化により,活性レプリコンが増加し,レプリケーションフォークの進行が変化します.
- 腫瘍遺伝子によるDDRの活性化には,DNAの複製が必要です.
結論:
- OISは,腫瘍遺伝子が誘発したDNAハイパーレプリケーションによって引き起こされたDDRの強制による結果である.
- DDRは,腫瘍遺伝子を駆動する細胞変異を防ぐために不可欠です.
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