RAF抑制剂主要是野生型RAF来激活MAPK通路并增强生长
Georgia Hatzivassiliou1, Kyung Song, Ivana Yen
1Genentech, South San Francisco, California 94080, USA. hatzivassiliou.georgia@gene.com
Nature
|February 5, 2010
概括
在癌症治疗中,RAF激酶抑制剂具有双重作用. 它们抑制BRAF突变瘤,但可以激活KRAS突变瘤中的RAS依赖途径,影响治疗策略.
科学领域:
- 在瘤学瘤学.
- 分子生物学分子生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- KRAS和BRAF的激活突变在人类癌症中很常见,包括黑色素瘤.
- 在RAS-RAF-MEK-ERK信号通路中,RAF激酶是关键的效应因子.
- 具有ATP竞争力的RAF抑制剂对BRAF突变瘤有效,但对RAS突变瘤不有效.
研究的目的:
- 在不同的细胞环境中研究ATP竞争性RAF抑制剂的对立机制.
- 阐明RAF抑制剂如何影响KRAS突变和野生型瘤中的RAS-RAF-MEK-ERK通路.
- 提供关于RAF抑制剂的治疗应用的见解.
主要方法:
- 在体外激酶测试以评估RAF活动.
- 细胞测试以评估MAPK通路信号传递.
- 异种移植模型在体内研究瘤生长.
主要成果:
- RAF抑制剂阻断了MAPK信号传递,并减少了BRAF (V600E) 瘤中的瘤生长.
- 在KRAS突变和RAS/RAF野生型瘤中,RAF抑制剂激活RAF-MEK-ERK通路.
- 抑制剂结合会诱导RAF二分化和RAS-GTP相互作用,独立于激酶抑制.
结论:
- 具有ATP竞争性的RAF抑制剂可以作为基于细胞环境的信号通路的抑制剂或激活剂.
- RAF抑制剂的有效性取决于上下文,受RAS突变状态的影响.
- 基于这些发现,针对RAF抑制剂提出了新的治疗策略.
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