Chari Raj, Coe Bradley P, Vucic Emily A, Lockwood William W, Lam Wan L
Department of Integrative Oncology, BC Cancer Research Centre, Vancouver, BC, Canada.
BMC Syst Biol. 2010 May 17;4:67. doi: 10.1186/1752-0509-4-67.
Genomics has substantially changed our approach to cancer research. Gene expression profiling, for example, has been utilized to delineate subtypes of cancer, and facilitated derivation of predictive and prognostic signatures. The emergence of technologies for the high resolution and genome-wide description of genetic and epigenetic features has enabled the identification of a multitude of causal DNA events in tumors. This has afforded the potential for large scale integration of genome and transcriptome data generated from a variety of technology platforms to acquire a better understanding of cancer.
Here we show how multi-dimensional genomics data analysis would enable the deciphering of mechanisms that disrupt regulatory/signaling cascades and downstream effects. Since not all gene expression changes observed in a tumor are causal to cancer development, we demonstrate an approach based on multiple concerted disruption (MCD) analysis of genes that facilitates the rational deduction of aberrant genes and pathways, which otherwise would be overlooked in single genomic dimension investigations.
Notably, this is the first comprehensive study of breast cancer cells by parallel integrative genome wide analyses of DNA copy number, LOH, and DNA methylation status to interpret changes in gene expression pattern. Our findings demonstrate the power of a multi-dimensional approach to elucidate events which would escape conventional single dimensional analysis and as such, reduce the cohort sample size for cancer gene discovery.
基因组学已极大地改变了我们开展癌症研究的方法。例如,基因表达谱分析已被用于划分癌症亚型,并有助于推导预测性和预后性特征。用于对遗传和表观遗传特征进行高分辨率全基因组描述的技术的出现,使得在肿瘤中能够识别出大量因果性DNA事件。这为大规模整合从各种技术平台生成的基因组和转录组数据以更好地理解癌症提供了可能。
在此我们展示了多维基因组数据分析如何能够解读破坏调控/信号级联反应及下游效应的机制。由于在肿瘤中观察到的并非所有基因表达变化都是癌症发展的因果因素,我们展示了一种基于对基因进行多重协同破坏(MCD)分析的方法,该方法有助于合理推断异常基因和通路,否则这些在单基因组维度研究中会被忽视。
值得注意的是,这是首次通过对DNA拷贝数、杂合性缺失和DNA甲基化状态进行平行整合全基因组分析来对乳腺癌细胞进行全面研究,以解读基因表达模式的变化。我们的研究结果证明了多维方法在阐明那些会逃过传统单维分析的事件方面的强大作用,因此,在癌症基因发现中可减少队列样本量。