RAF阻害剤は,MAPK経路を活性化し,成長を促進するために,野生型のRAFを活性化します
Georgia Hatzivassiliou1, Kyung Song, Ivana Yen
1Genentech, South San Francisco, California 94080, USA. hatzivassiliou.georgia@gene.com
Nature
|February 5, 2010
まとめ
RAFキナーゼ阻害剤は,がん治療において二重作用を示しています. BRAF変異腫瘍を阻害するが,KRAS変異腫瘍のRAS依存経路を活性化させ,治療戦略に影響を与える.
科学分野:
- 腫瘍学 腫瘍学
- 分子生物学は分子生物学である.
- 薬理学 薬理学とは
背景:
- KRASとBRAFの活性化突然変異は,メラノーマを含むヒトの癌で一般的です.
- RAFキナーゼは,RAS-RAF-MEK-ERK信号伝達経路における重要な効果因子である.
- ATP競争性のRAF阻害剤は,BRAF変異性腫瘍に対して有効ですが,RAS変異性腫瘍に対しては有効ではありません.
研究 の 目的:
- 異なる細胞環境におけるATP競争性のRAF阻害剤の対抗メカニズムを調査する.
- RAF阻害剤が,KRAS変異型および野生型腫瘍におけるRAS-RAF-MEK-ERK経路にどのように影響するか解明する.
- RAF阻害剤の治療的応用に関する洞察を提供するために.
主な方法:
- RAFの活動を評価するためのインビトロキナーゼアッセイ.
- MAPK経路のシグナル伝達を評価するための細胞検査.
- 腫瘍の成長を研究するXenograftモデル in vivo.
主要な成果:
- RAF阻害剤はMAPKシグナル伝達を阻害し,BRAF (V600E) 腫瘍の腫瘍増殖を抑制する.
- RAF阻害剤は,KRAS変異体およびRAS/RAFワイルド型腫瘍におけるRAF-MEK-ERK経路を活性化する.
- 阻害剤の結合は,キナーゼ抑制とは無関係にRAF二分化とRAS-GTP相互作用を誘導する.
結論:
- ATP-競合RAF阻害剤は,細胞文脈に基づいて信号伝達経路の阻害剤またはアクティベーターとして作用することができます.
- RAF阻害剤の有効性は文脈に依存し,RAS変異状態の影響を受けます.
- これらの発見に基づいて,RAF阻害剤に対する新しい治療戦略が提案されています.
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