瘤抑制剂Par-4激活了细胞亡的外部途径
Ravshan Burikhanov1, Yanming Zhao, Anindya Goswami
1Department of Radiation Medicine, University of Kentucky, Lexington, KY 40536, USA.
Cell
|July 28, 2009
概括
前列腺亡反应-4 (Par-4) 是由细胞分泌的,并通过结合细胞表面GRP78.8诱导癌细胞亡. 这种细胞外Par-4信号激活了死亡途径,提供了一个潜在的治疗目标.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 癌症研究 癌症研究
背景情况:
- 前列腺亡反应-4 (Par-4) 是一种已知的细胞内亡蛋白质.
- 意外地发现,Par-4是由正常细胞和癌细胞分泌的.
- 在Par-4转基因小鼠中的瘤耐药性表明分泌的Par-4的作用.
研究的目的:
- 研究细胞外Par-4分泌的机制和功能.
- 确定通过细胞外Par-4诱导亡的受体和途径.
- 探索细胞外Par-4在TRAIL诱导的亡中的作用.
主要方法:
- 细胞培养和使用ER诱导压力剂的治疗.
- 对Par-4分泌通路的分析 (brefeldin A敏感度).
- 研究细胞外的Par-4与细胞表面蛋白的相互作用 (GRP78) 和下游信号 (FADD/caspase通路).
主要成果:
- 细胞自发分泌Par-4,其分泌因ER压力而增强,通过Brefeldin A敏感通路.
- 细胞外Par-4通过结合细胞表面GRP78.8诱导癌细胞的亡.
- 这种相互作用触发了ER压力,并激活了FADD/caspase-8/caspase-3的亡途径.
- TRAIL诱导的亡依赖于通过细胞表面GRP78.8传递的细胞外Par-4信号.
结论:
- 细胞外Par-4作为一个信号分子,诱导癌细胞特异性亡.
- 帕-4/细胞表面GRP78相互作用代表了一种新的外部亡途径.
- 这一途径为癌症治疗提供了潜在的治疗策略.
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