通过受损的DNA预复制复合体功能阻碍对PARP的抗性而独立于BRCA2逆转基因突变
Kyrie Pappas1, Matteo Ferrari2, Perianne Smith3
1Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065.
概括
在前列腺癌中,PARPi耐药性与DNA预复制复合物有关. 针对这个复合体可能会恢复BRCA突变瘤中的PARPi敏感性.
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:
- 聚合物腺二酸核糖 (poly(ADP-核糖) 聚合酶抑制剂 (PARPi) 已被批准用于治疗BRCA突变转移性割抵抗性前列腺癌.
- 了解PARPi抵抗机制,包括由于逆转突变导致的前期抵抗和复发,至关重要.
- 在PARPi敏感性中DNA预复制复合体 (pre-RC) 的作用仍然不清楚.
研究的目的:
- 为了确定赋予BRCA突变前列腺癌中PARPi耐药性的基因组因素,独立于逆转突变.
- 阐明前RC和PARPi灵敏度之间的机制联系.
- 探索克服PARPi耐药性的治疗策略.
主要方法:
- 在小鼠Brca2-突变前列腺器官中全基因组的CRISPR屏幕.
- 对RC前组件 (Cdt1,Cdc6,Dbf4) 和双胞胎的基因操纵.
- 对奥拉巴里布和AZD5305.5的敏感性评估.
- 对DNA损伤分辨率和复制叉稳定性的分析.
- 在人类CRPC瘤中对RC前基因拷贝数变化的评估.
主要成果:
- 在RC前组件 (Cdt1,Cdc6,Dbf4) 的耗尽使其对PARPi产生了耐药性 (olaparib,AZD5305).
- 在Brca2-突变,Cdc6-贫乏细胞中,双氨酸的抑制恢复了PARPi的敏感性.
- ~50%的抗割前列腺癌 (CRPC) 瘤显示在RC前基因中的副本数损失,特别是CDT1.
- 损坏的RC前活动导致DNA损伤的更快解决,并保护了复制分叉.
- 一种CDT1/双胞胎抑制剂 (AF615) 恢复了对AZD5305.5的敏感性.
结论:
- DNA预复制复合体是BRCA突变前列腺癌中PARPi敏感性的关键决定因素.
- 损坏的RC前功能使癌细胞能够逃避PARPi诱导的复制压力.
- 针对CDT1/ geminin复合体提供了一个潜在的策略,使瘤重新敏感于PARPi疗法.
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