一个RAS•GTP:RanGAP1复合物的亲癌性非正规活性促进核蛋白出口
Brajendra K Tripathi1, Nicole H Hirsh2, Xiaolan Qian2
1Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA. tripathib@mail.nih.gov.
Nature cancer
|November 11, 2024
概括
研究人员发现了一种新的致癌RAS信号通路,该通路将核蛋白移动到细胞质中,独立于PI3K/AKT和RAF/MEK. 这一途径涉及RAS•GTP,XPO1和RanGAP1,通过降解DLC1.1等瘤抑制剂促进癌症.
科学领域:
- 在瘤学瘤学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 佳能RAS信号主要涉及血相互作用和PI3K/AKT和RAF/MEK通路.
- 瘤性RAS蛋白在癌症的发展和进展中起着至关重要的作用.
- 核细胞质运输对细胞功能至关重要,在癌症中可能受到失调.
研究的目的:
- 为了识别和描述一种新的,非正规的瘤性RAS信号通路.
- 阐明RAS促进核蛋白出口的分子机制.
- 探索针对这种新发现的RAS活动的治疗策略.
主要方法:
- 研究了与核出口机械的RAS•GTP相互作用.
- 利用生物化学分析来研究蛋白质复合体的形成和酶活性.
- 研究了XPO1,RangGAP1,EZH2和DLC1在RAS中介核出口中的作用.
- 评估了抑制这种途径对瘤抑制功能和癌细胞行为的影响.
主要成果:
- 确定了一种非正规的RAS•GTP活动,促进了XPO1依赖的核蛋白出口,独立于PI3K/AKT和RAF/MEK.
- 证明了RAS•GTP与RanGAP1形成了一个环核复合体,促进Ran•GTP的水解和核货物的释放.
- 表明核EZH2的出口导致DLC1瘤抑制剂的细胞质降解.
- 发现抑制核出口可以增强KRAS抑制的抗瘤作用.
结论:
- 一个新的瘤性RAS途径通过增强核蛋白出口驱动癌症的进展.
- 针对这种非正规的RAS活动,可能通过防止核出口,提供了一个新的治疗途径.
- 将RAS抑制剂与DLC1再激活或其他癌症治疗相结合可能会改善治疗结果.
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