Systematic Profiling of Nonhomologous End Joining in Cancer

描述(申请人提供)：癌症疗法通常通过使染色体断裂并超过肿瘤细胞修复它们的能力来杀死肿瘤。非同源末端连接(NHEJ)可以解决大部分此类断裂，有研究表明，癌症可能在执行NHEJ方面存在显著差异。我们将确定NHEJ在各种癌症中的适合度有多大的差异。我们将用一种特异和灵敏的定量聚合酶链式反应(QPCR)检测NHEJ的效率。我们还将采用下一代测序技术来表征并行NHEJ的准确性。重要的是，引入染色体断裂的癌症疗法在杀死细胞方面是有效的，因为它们引入了“肮脏”的断裂--断裂往往会对断裂两侧的DNA造成损害，使其难以修复。使用具有已知NHEJ缺陷的细胞系(包括来自遗传性NHEJ缺陷患者的细胞)，我们已经证明，如果NHEJ要以与癌细胞和周围正常细胞在癌症治疗中存活的能力一致的方式进行评估，那么脏端结构的使用是至关重要的。我们将系统地描述NHEJ在一组癌细胞系以及原发癌症中的适合性。我们将确定NHEJ中与癌症相关的变异的程度，以及这种变异是否有助于预测治疗结果和帮助开发更好的(合理设计和有针对性的)疗法。

DESCRIPTION (provided by applicant): Cancer therapies often kill tumors by making chromosome breaks, and exceeding the tumor cell's ability to repair them. Nonhomologous end joining (NHEJ) resolves the majority of such breaks, and it has been suggested that cancers might differ significantly in how well they perform NHEJ. We will determine how much NHEJ fitness varies in a variety of cancers. We will measure efficiency of NHEJ with a specific and sensitive quantitative polymerase chain reaction (qPCR) assay. We will additionally employ next generation sequencing technology to characterize in parallel NHEJ accuracy. Importantly, cancer therapies that introduce chromosome breaks are effective in killing cells because they introduce breaks that are "dirty" - the break often has damage to DNA flanking the break that makes it difficult to repair. Using cell lines with known NHEJ defects (including cells from patients with inherited NHEJ defects), we have shown the employment of dirty end structures is critical if NHEJ is to evaluated in a manner consistent with the ability of cells, both cancer and surrounding normal cells, to survive cancer therapies. We will systematically profile NHEJ fitness in both a panel of cancer cell lines as well as in primary cancers. We will determine the extent of cancer-associated variation in NHEJ, and whether this variation could help predict therapy outcome and aid in development of better (rationally designed and targeted) therapies.