マトリックスクロスリンクは,インテグリンシグナル伝達を強化することによって,腫瘍の進行を促します
Kandice R Levental1, Hongmei Yu, Laura Kass
1Department of Bioengineering and Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
Cell
|November 26, 2009
まとめ
コラーゲンのクロスリンクによって引き起こされる腫瘍の硬さは,焦点結合とPI3キナーゼの活性を増やすことで癌を促進します. このクロスリンクを減らすことは悪性腫瘍を阻害し,乳がんにおける腫瘍発生率を下げる.
科学分野:
- 腫瘍学 腫瘍学
- バイオケミストリー バイオケミストリー
- バイオフィジックス 生物物理学
背景:
- 腫瘍は細胞外マトリックス (ECM) の改造と硬化を示すが,がんの進行における硬化の役割は十分に理解されていない.
- ECMの改造は癌で認められているが,ECMの硬化が腫瘍形成に与える具体的な貢献は,さらなる解明を必要としている.
研究 の 目的:
- 乳がんの進行におけるコラーゲンのクロスリンクとECMの硬化が果たす役割を調査する.
- ECMの硬さ,焦点粘着,PI3キナーゼシグナル伝達,および乳腺の悪性腫瘍の間のメカニズム的関連を決定する.
主な方法:
- リシル酸化酵素を用いたコラーゲンクロスリンクの誘導および抑制.
- ECMの硬さ,焦点粘着,PI3キナーゼ (PI3K) 活性に関する評価.
- MMTV-Neuマウスモデルを使用して,腫瘍発生率と線維症を評価するインビボ研究.
主要な成果:
- コラーゲンのクロスリンクは,ECMの硬化,焦点粘着の増加,PI3Kの活性の増加,および上皮の侵入を促進しました.
- インテグリンシグナリングの阻害は,硬化したECMへの侵入を減少させ,インテグリンクラスタリングは焦点結合とPI3Kシグナリングを促進しました.
- リシル酸化酵素媒介によるコラーゲンのクロスリンクの減少は,線維症を予防し,焦点粘着とPI3Kの活性を減少させ,乳腺の悪性腫瘍を阻害しました.
結論:
- コラーゲン・クロスリンクは,乳がん発生におけるECM硬化と線維症の主要な要因である.
- コラーゲン・クロスリンクによって媒介されるECMの硬化は,焦点結合とPI3Kシグナル伝達を促進し,乳がんの進行を促します.
- リシル酸化酵素媒介のコラーゲンクロスリンクをターゲットにすることは,乳がんを予防する潜在的な治療戦略です.
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