腫瘍抑制剤Par-4は,アポトーシスの外部経路を活性化させます
Ravshan Burikhanov1, Yanming Zhao, Anindya Goswami
1Department of Radiation Medicine, University of Kentucky, Lexington, KY 40536, USA.
Cell
|July 28, 2009
まとめ
前立腺アポトーシス反応-4 (Par-4) は細胞によって分泌され,細胞表面のGRP78.8に結合することによって癌細胞アポトーシスを誘導します. この細胞外Par-4シグナリングは,死の経路を活性化し,潜在的な治療目標を提供します.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- がん研究 がん研究
背景:
- 前立腺アポプトシス反応-4 (Par-4) は,細胞内プロアポプトシスタンパク質として知られています.
- Par-4は,意外に,正常細胞と癌細胞の両方で分泌されていることが判明しました.
- Par-4変異遺伝子マウスの腫瘍抵抗は,分泌されるPar-4の役割を示唆している.
研究 の 目的:
- 細胞外Par-4分泌のメカニズムと機能を調査する.
- 細胞外Par-4がアポトーシスを誘発する受容体と経路を特定する.
- TRAIL誘発のアポトーシスにおける細胞外Par-4の役割を調査する.
主な方法:
- 細胞培養とERストレス誘発剤による治療.
- Par-4分泌経路の分析 (ブレフェルディンA感度).
- 細胞外Par-4相互作用と細胞表面タンパク質 (GRP78) と下流シグナル伝達 (FADD/カスパース経路) を調査する.
主要な成果:
- Par-4は細胞によって自発的に分泌され,その分泌はブレフェルディンA敏感経路経由でERストレスによって強化されます.
- 細胞外Par-4は,細胞表面GRP78.8と結合することで,癌細胞におけるアポトーシスを誘発する.
- この相互作用はERストレスを引き起こし,FADD/caspase-8/caspase-3アポプトシス経路を活性化する.
- TRAIL誘発アポトーシスは,細胞表面GRP78.8を通じた細胞外Par-4シグナル伝達に依存しています.
結論:
- 細胞外Par-4は,がん細胞特異的なアポトーシスを誘発するシグナル分子の役割を果たします.
- Par-4/細胞表面GRP78の相互作用は,新しい外部アポプトシス経路を表しています.
- この経路は,がん治療の潜在的な治療戦略を提供します.
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