在BRCA1二次拼接部位的突变驱动了表突跳转和PARP抑制剂耐药性
Ksenija Nesic1,2, John J Krais3,4, Yifan Wang3
1The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.
Molecular cancer
|August 5, 2024
概括
卵巢癌中PARP抑制剂耐药性可以通过BRCA1外因突破发生,由二次拼接位突变驱动. 监测这些突变为克服治疗耐药性的新策略提供了机会.
科学领域:
- 在瘤学瘤学.
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- PARP抑制剂 (PARPi) 治疗对缺乏同源重组修复 (HRR) 的卵巢癌有效,特别是那些具有BRCA1/2突变的卵巢癌.
- PARPi 耐药性是一个重大的临床挑战,已经确定了各种机制,包括二次突变.
- 像△11和△11q这样的BRCA1拼接异型可以通过改变蛋白质功能来促进PARPi耐药性,但它们的临床相关性尚未完全理解.
研究的目的:
- 为了研究BRCA1外显子跳跃在PARPi耐药性中的作用.
- 为了确定BRCA1外基突变跳转的潜在驱动因素.
- 在卵巢癌患者中评估BRCA1拼接位突变的临床意义.
主要方法:
- 在九个卵巢和乳腺癌患者衍生异种移植 (PDX) 中分析了BRCA1外因子11跳转和治疗反应.
- 使用qRT-PCR,RNA测序,免疫阻塞和小基因测试对二次BRCA1拼接位突变 (SSM) 的表征.
- 使用CRISPR/Cas9.9验证外子跳跃作为一种抵抗机制.
- 在PARPi后的卵巢癌患者队列中对SSM进行丰富分析 (ARIEL2,ARIEL4).
主要成果:
- 在抗PARPi的PDX瘤中,BRCA1外因子11跳转升高.
- 在两个独立的PDX模型中,确定驱动异构突变跳转的二次BRCA1SSM.
- 作为PARPi电阻机制的外子跳转的功能验证.
- 用PARPi治疗的卵巢癌患者中SSM的丰富.
结论:
- 二次突变劫持拼接部位增强BRCA1外因子跳转,导致PARPi耐药性.
- BRCA1 SSM 促进了低形态 BRCA1 变体的过度表达,从而导致耐药性.
- 建议对BRCA1SSM进行临床监测,同时还要对恢复框架的突变进行监测,以控制PARPi耐药性.
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