IAPアンタゴニストはcIAP1を標的とし,TNFアルファ依存アポトシスを誘発する
James E Vince1, W Wei-Lynn Wong, Nufail Khan
1Department of Biochemistry, La Trobe University, Kingsbury Drive, Melbourne, VIC 3086, Australia.
Cell
|November 21, 2007
まとめ
IAPアンタゴニストは,XIAPを抑制するだけでなく,NF-kappaBシグナル伝達とTNFalpha生成を活性化することによって腫瘍細胞死を誘発する. この経路を遮断すると,腫瘍細胞が生き残り,新たながん治療戦略が示唆される.
科学分野:
- 分子生物学は分子生物学である.
- がん生物学 がん生物学
- 免疫学 免疫学とは
背景:
- X関連アポトーシスタンパク質阻害剤 (XIAP) はアポトーシスの重要な調節剤である.
- IAPアンタゴニスト (IAC) は,XIAPを阻害し,腫瘍細胞死を誘発するように設計されています.
- 以前の理解では,IACsは主にミトコンドリア後のカスパスを標的としていることが示唆されていた.
研究 の 目的:
- IAPアンタゴニストによって誘発されるアポトーシスのメカニズムを調査する.
- IAC媒介による細胞死におけるカスパース8とNF-カッパBのシグナル伝達の役割を決定する.
- ガン治療におけるIACの新たな治療的応用を探求する.
主な方法:
- IAPアンタゴニストとカスパース8阻害剤による腫瘍細胞の治療.
- NF-kappaBのシグナリング活性化とTNFalpha生成の分析.
- アポトーシス誘導に対する細胞の感受性の評価.
主要な成果:
- IAPアンタゴニストは,期待に反して,カスパース8阻害剤によって阻害されるアポトーシスを誘導します.
- IACは,cIAP1を阻害することによってNF-kappaBシグナル伝達を活性化します.
- NF-kappaBによって刺激されたTNFalphaの生成は,自己決定性腫瘍細胞の死亡を媒介する.
- NF-kappaBまたはTNFalphaの抑制は,IAC誘発のアポトーシスから腫瘍細胞を救う.
- IAC治療またはcIAP1デリエーションは,細胞を外因的なTNFalpha誘発のアポトーシスに敏感にします.
結論:
- IAPアンタゴニストは,XIAP抑制だけでなく,NF-kappaBとTNFalphaを含むメカニズムを通じて細胞死を誘発する.
- NF-kappaBシグナル伝達またはTNFalphaをターゲットにすることは,IACに対する抵抗を克服するための潜在的な戦略です.
- IACは,がん治療のためのTNFalphaベースの治療法と併用して新しい治療用途を持つ可能性があります.
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