不匹配的修复缺陷不足以引起瘤免疫性
Peter M K Westcott1,2, Francesc Muyas3, Haley Hauck4
1David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA. westcott@cshl.edu.
Nature genetics
|September 14, 2023
概括
大多数DNA不匹配修复缺陷 (dMMR) 瘤由于突变异质性而抵抗免疫检查点阻塞 (ICB). 克隆性新抗原负担,而不是亚克隆性,预测dMMR癌症中的ICB反应.
科学领域:
- 在瘤学瘤学.
- 免疫学 免疫学 免疫学
- 遗传学 是一个遗传学.
背景情况:
- DNA不匹配修复缺陷 (dMMR) 通常导致高瘤突变负担 (TMB) 和对免疫检查点阻塞 (ICB) 的敏感性.
- 然而,很大一部分dMMR瘤对ICB表现出耐药性,这凸显了对瘤免疫监测和TMB的理解上的差距.
- 瘤内部异质性和新抗原呈现是影响治疗疗效的关键因素.
研究的目的:
- 调查dMMR癌症中免疫逃避背后的机制,尽管高TMB.
- 确定免疫监测在塑造瘤克隆架构和新抗原景观中的作用.
- 为了确定dMMR瘤中ICB反应的预测生物标志物.
主要方法:
- 开发针对dMMR肺癌和结肠癌的本土小鼠模型.
- 在临床前模型中分析T细胞透和对ICB的反应.
- 评估内突变异质性和克隆结构.
- 评估新抗原负担 (克隆性与亚克隆性) 和T细胞反应.
- 在dMMR胃癌和结直肠癌的临床试验数据中,新抗原负荷与ICB反应的相关性.
主要成果:
- dMMR小鼠模型出乎意料地显示了有限的T细胞透和ICB反应,这归因于显著的内突变异质性.
- 免疫监测影响了瘤的克隆组成,但没有影响整体新抗原负载.
- 对亚克隆新抗原的T细胞反应减少.
- 与亚克隆不同的是,克隆新抗原负担在临床dMMR癌症队列中成为ICB反应的预测因素.
结论:
- 瘤内部异质性是高TMB的dMMR癌症中免疫逃避的一个关键机制.
- 免疫监测塑造了瘤的进化,但T细胞对亚克隆新抗原的识别受损.
- 克隆新抗原负荷是预测dMMR恶性瘤中ICB疗效的有希望的生物标志物.
- 这些发现对优化针对高TMB癌症的免疫疗法具有重大意义.
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