Chk1抑制了对DNA损伤的caspase-2核突变反应,该反应绕过了p53,Bcl-2和caspase-3的破坏
Samuel Sidi1, Takaomi Sanda, Richard D Kennedy
1Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
Cell
|May 31, 2008
概括
检查点激酶1 (Chk1) 抑制通过激活替代性亡途径,恢复了癌细胞中DNA损伤诱导的细胞死亡. 这种Chk1-抑制的途径绕过p53突变和Bcl-2过度表达,提供了新的治疗策略.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 癌症研究 癌症研究
背景情况:
- 癌细胞通过p53突变或Bcl-2家族蛋白质过度表达来逃避亡,导致恶性转变和治疗耐药性.
- 检查点激酶1 (Chk1) 在DNA损伤反应中起着关键作用,其抑制正在作为癌症治疗策略进行探索.
研究的目的:
- 研究Chk1抑制恢复癌细胞中DNA损伤诱导的亡的机制.
- 确定关键的分子参与者和参与Chk1抑制剂介导细胞死亡的途径.
主要方法:
- 使用p53突变和人类瘤细胞系的斑马鱼胚胎.
- 使用马辐射诱导DNA损伤.
- 评估了亡,DNA碎片化,以及酶 (酶-3,酶-2) 和酶 (ATM,ATR) 的激活.
- 研究了p53和Bcl-2家族蛋白在亡过程中的作用.
主要成果:
- 在p53突变斑马鱼胚胎中, Chk1的耗尽或抑制恢复了马辐射诱导的亡.
- 鉴定出了一种独立于caspase-3激活的新型亡程序.
- 这种替代途径需要ATM,ATR和caspase-2,并且不受p53损失或Bcl-2/xl过度表达的影响.
- 用Chk1抑制剂治疗的人类瘤细胞激活ATM,ATR和caspase-2,导致caspase-2依赖的亡,绕过p53缺乏和Bcl-2过量.
结论:
- 进化保存的"Chk1-抑制"途径代表了一种新型的亡过程.
- 这种途径对Chk1抑制剂有反应,对p53和Bcl-2的变化不敏感.
- 向Chk1为亡调节缺陷的癌症提供了一个有前途的治疗策略,无论p53或Bcl-2状态如何.
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