Quantitative Adductomics Approaches for Assessing the Occurrence and Repair of DNA Adducts

本申请的长期目标是发现和表征基于内收切断术的暴露 评估癌症风险和预防癌症的指标。内源性代谢和 环境暴露都可能导致DNA损伤。如果不修复，产生的DNA加合物可能 通过抑制DNA复制和转录以及诱导突变来损害遗传信息的流动 在这些过程中。此外，DNA加合物在哺乳动物细胞和组织中积累的最终水平 是DNA加合物形成和修复之间动态相互作用的结果。因此，重要的是建立 一种用于定量测量广泛的DNA加合物的稳健分析方法， 癌症和其他人类疾病发展的病因学。这种方法还将使 DNA加合物修复的特征，这可能导致发现癌症发生的风险因素 和发展，并指导有效的癌症化学预防方法的发展。在这 应用，我们建议建立一个DNA内收体的方法，采用和扩大我们最近 建立了LC-MS/MS方法来定量活性氧自由基诱导的DNA加合物，DNA 紫外线照射产生的光产物和DNA表观遗传标记，它们代表了 DNA内收酶然后，我们将采用这种内收的方法来研究的调制， 氧化诱导的DNA损伤水平和DNA修复酶的DNA表观遗传标记，用于评估 DNA加合物在黑色素瘤发病病因学中的意义，以及评价 防晒成分对改变UV诱导的DNA加合物形成的影响。这项研究将有很长的时间- 通过提供简单的内收切除术平台，对DNA损伤修复和癌症生物学领域产生持久影响 用于表征调节形成的风险因素和治疗/预防方法， 去除DNA加合物。

The long-term objective of this application is to discover and characterize the adductomics-based exposure indicators for the assessment of cancer risks and for cancer prevention. Endogenous metabolism and environmental exposure can both give rise to DNA damage. If left unrepaired, the resulting DNA adducts may compromise the flow of genetic information by inhibiting DNA replication and transcription and inducing mutations in these processes. In addition, the ultimate levels of DNA adducts accumulated in mammalian cells and tissues are the result of a dynamic interplay between DNA adduct formation and repair. Thus, it is important to establish a robust analytical method for the quantitative measurement of a broad range of DNA adducts that are implicated in the etiology for the development of cancer and other human diseases. Such a method will also enable the characterizations of the repair of DNA adducts, which may lead to the discovery of risk factors for cancer initiation and development, and guide the development of approaches for effective cancer chemoprevention. In this application, we propose to establish a DNA adductomic approach by employing and expanding our recently established LC-MS/MS methods for the quantification of DNA adducts induced by reactive oxygen species, DNA photoproducts arising from UV irradiation, and DNA epigenetic marks, which represent a substantial subset of the DNA adductome. We will then employ this adductomic approach for investigating the modulations of the levels of oxidatively induced DNA lesions and DNA epigenetic marks by DNA repair enzymes, for assessing the implications of DNA adducts in the etiology of melanoma development, and for evaluating the effects of sunscreen components on altering UV-induced DNA adduct formation. The proposed research will have a long- lasting impact on the fields of DNA damage repair and cancer biology by offering a facile adductomic platform for characterizing the risk factors and therapeutic/preventive approaches that modulate the formation and removal of DNA adducts.