ブラフキナーゼ不活性変異体が肺腺癌を誘発する
Patricia Nieto1, Chiara Ambrogio1, Laura Esteban-Burgos1
1Experimental Oncology, Molecular Oncology Programme, Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain.
Nature
|August 8, 2017
まとめ
BRAF変異の不活性化により,MAPKのシグナル伝達が変化し,肺腺がんが発症する. ワイルド型BRAFは腫瘍の成長に不可欠で その喪失は致命的な病変につながる可能性があります
科学分野:
- 腫瘍学
- 分子生物学
- 癌 の 遺伝子
背景:
- 肺アデノカルシノーマの発症の原因はしばしば不明であり,標的治療の開発を阻害する.
- 他の癌に共通する活性化変異とは異なり,非活性化BRAF変異は肺腫瘍に多く見られます.
研究 の 目的:
- 肺腫瘍形成における発症因子としてのBRAF不活性化変異の役割を調査する.
- 肺腺がんの発症と進行におけるBRAF,KRAS,MAPK信号の相互作用を調査する.
主な方法:
- キナーゼ無活性Braf (D631A) とKras (G12V) 変異を発現するマウスモデル.
- 腫瘍の発生,進行,細胞のタイプ差異の分析
- MAPKシグナリングを調節するためにMEK (メク) の薬理学的抑制.
主要な成果:
- キナーゼ無活性Braf ((D631A) の発現は,マウスの肺腺がんを誘発する.
- Kras ((G12V)) と Braf ((D631A)) の共発は,Craf キナーゼ経由で腫瘍の発現と進行を加速する.
- 野生型Brafの消去は,MAPK信号伝達と腫瘍性毒性を増加させるが,クラブ細胞の変異と致死性病変を引き起こす.
結論:
- BRAFを不活性化する変異が肺癌の起因である.
- MAPK経路の信号強度は,腫瘍の表型と細胞起源を決定する.
- BRAFを標的とし,MAPK経路のダイナミクスを理解することは,肺腺癌の治療において極めて重要です.
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