在机械模型中对染色体不稳定性测量的调查
Andrew R Lynch1,2, Shermineh Bradford1,2, Amber S Zhou1,2
1Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI 53705.
概括
在癌症中测量染色体不稳定性 (CIN) 是具有挑战性的. 与评估CIN进展的传统技术相比,成像和DNA测序等单细胞方法提供了更高的灵敏度和全面性.
科学领域:
- 癌症生物学 癌症生物学
- 遗传学 遗传学 是一个
- 基因组学就是基因组学.
背景情况:
- 染色体不稳定 (CIN) 是癌症的标志,其特点是由于细胞分裂期间染色体分离错误而导致持续的型变化.
- 不同水平的CIN影响瘤进展,但在人类癌症中准确量化错误分离率仍然很困难.
- 现有的CIN测量方法在敏感性和适用于临床样本方面的限制.
研究的目的:
- 系统地评估和比较各种测量染色体不稳定性 (CIN) 方法的定量准确性和灵敏性.
- 确定最可靠和临床适用的技术,以评估不同癌症表型的CIN.
- 为报告CIN率提出一个标准化的单位,以促进交叉方法的比较.
主要方法:
- 利用特定的,可诱导的表型CIN模型来产生染色体错误分离事件.
- 评估CIN使用固定和时差光显微镜,染色体扩散,六中位素FISH,批量转录组学和单细胞DNA测序 (scDNAseq).
- 在所有使用的方法中比较了定量相关性和灵敏度.
主要成果:
- 显微镜和细胞遗传学 (染色体扩散,FISH) 显示了与CIN的显著相关性,但对低率的敏感性有限.
- 大量转录和基因组DNA签名 (CIN70,HET70) 没有检测到CIN.
- 单细胞DNA测序 (scDNAseq) 显示出高灵敏度,与成像方法有很强的相关性,对临床样本来说是最全面的.
结论:
- 单细胞方法,特别是scDNAseq,在临床环境中对CIN的敏感和全面测量更为优越.
- 显微镜和细胞遗传学对低CIN率有价值,但比单细胞方法敏感度低.
- 建议建立一个标准化单元"每次双胞胎分裂的错误分离",以统一CIN速率报告.
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