通过类似癌症的机制,PIK3CA和CCM突变为洞穴生物提供燃料
Aileen A Ren1, Daniel A Snellings2, Yourong S Su3
1Department of Medicine and Cardiovascular Institute, University of Pennsylvania, Philadelphia, PA, USA.
Nature
|April 28, 2021
概括
由于PI3K-mTOR通路的激活和CCM复合体的丧失,大脑洞腔形 (CCM) 的增长. 像拉巴胺素这样的mtork1抑制剂在阻断CCM形成方面表现有前途,并且可以治疗侵袭性血管形.
科学领域:
- 血管生物学
- 分子遗传学
- 癌症学
背景情况:
- 大脑洞腔形 (CCM) 是与CCM蛋白质复合体无活化相关的血管形.
- 对于CCM的快速生长和临床后果,如中风和发作,目前尚不清楚.
- 了解CCM生长的分子驱动因素对于开发有效治疗至关重要.
研究的目的:
- 阐明导致脑洞形迅速增长的分子机制.
- 确定关键的信号通路和参与CCM病变的遗传变化.
- 探索攻击性CCM的潜在治疗目标.
主要方法:
- 对人体CCM样本进行PIK3CA和CCM复合基因的体质突变分析.
- 利用小鼠模型研究PI3K-mTOR信号传递和CCM复合体在内皮细胞中的作用.
- 在体内评估了mTORC1抑制剂Rapamycin在阻断CCM形成方面的有效性.
主要成果:
- CCM 的生长需要 PI3K-mTOR 信号的增加和 CCM 复合物的功能丧失.
- 在人类的CCM中,在相同的细胞中发现了PIK3CA的功能增益突变和CCM复合物的功能丧失突变.
- 在小鼠模型中,CCM功能丧失和KLF4表达增强了内皮mTOR信号传递,而拉巴胺素治疗抑制了CCM的形成.
结论:
- 一个类似于癌症的三击机制, 涉及瘤抑制剂的损失和瘤基因的增加, 驱动了侵略性的CCM.
- 用mTORC1抑制剂向PI3K- mTOR途径是攻击性CCM的一种潜在治疗策略.
- 经过临床批准的mTORC1抑制剂可用于治疗侵袭性脑洞形.
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