避开矛盾的MAPK通路激活的RAF抑制剂
Chao Zhang1, Wayne Spevak1, Ying Zhang1
1Plexxikon Inc., 91 Bolivar Drive, Berkeley, California 94710, USA.
Nature
|October 16, 2015
概括
下一代RAF抑制剂或"悖论破坏剂"有效地抑制由BRAF突变驱动的癌症生长,而没有悖论性途径激活. 与第一代RAF抑制剂相比,这些新药的疗效提高并克服了耐药性.
科学领域:
- 癌症学
- 分子生物学
- 药理学
背景情况:
- 致癌性BRAF突变通过MAPK途径驱动癌症,导致针对性治疗,如RAF抑制剂治疗黑色素瘤.
- 矛盾的是,第一代RAF抑制剂可以激活MAPK通路,刺激某些癌症的生长,特别是那些具有上游RAS或受体激酶激活的癌症.
- 这种矛盾的激活在癌症治疗中构成重大挑战,限制了疗效和耐用性.
研究的目的:
- 识别和描述下一代RAF抑制剂,称为"悖论破坏剂",可以选择性地抑制突变BRAF而无悖论MAPK通路激活.
- 在临床前癌症模型中评估这些悖论破坏剂的疗效,包括对第一代RAF抑制剂耐药的癌症.
- 评估悖论破坏剂克服抗药性机制的潜力,并提高RAF抑制剂治疗的安全性和耐用性.
主要方法:
- 开发和选新的ATP竞争性RAF抑制剂.
- 在BRAF或上游突变的癌细胞系和异种移植模型中进行RAF抑制剂的体外和体内测试.
- 对RAF抑制剂反应的MAPK通路信号,细胞增殖和基因表达的分析.
- 对第一代RAF抑制剂的耐药性机制的评估和克服它们的悖论破坏者的有效性.
主要成果:
- 下一代RAF抑制剂 (PLX7904,PLX8394) 抑制了突变的BRAF癌细胞而没有矛盾的MAPK通路激活.
- 与vemuurafenib不同,悖论破坏剂在HRAS突变的细胞中没有刺激生长或诱导MAPK通路响应基因.
- 对第一代RAF抑制剂的已知抗药机制的有效性得到证明.
结论:
- 下一代RAF抑制剂 ("悖论破坏剂") 通过将MAPK通路抑制与悖论激活分离,提供了一个有前途的治疗策略.
- 与第一代RAF抑制剂相比,这些药物具有提高安全性和更持久的疗效的潜力.
- 目前正在对PLX8394进行临床评估,这表明RAF抑制剂治疗可能发生范式转变.
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