Studies of cancer risk and prevention with a novel DNA damage-detection technique

利用新型 DNA 损伤检测技术研究癌症风险和预防

• 批准号: 7104735
• 负责人: ANTONIO M REIS
• 金额: $ 7.33万
• 依托单位: UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7104735
• 关键词: DNA; DNA damage; DNA repair; cancer risk; genes; human; lead; mutant; neoplasm /cancer; prevention

DESCRIPTION (provided by applicant): Our long term goal is prevention and treatment of cancer. In living cells DNA is continuously exposed to damage. Protective mechanisms (such as DNA repair) keep the level of damage low. But still unrepaired damage occurs. This is a problem as unrepaired damage may lead to mutations, and mutations in certain genes lead to cancer. Several reports suggest that individuals with currently unrecognized subtle deficits in their DNA repair capacity are prone to cancer. Unfortunately, detecting these individuals is currently technically challenging and, consequently, these individuals remain undiagnosed. We recently developed a novel technique for the detection of DNA damage. This technology may prove useful not only to measure levels of DNA damage (and therefore estimate cancer risk) but also to estimate the repair capacity of each individual. In the current proposal we have two specific aims: Aim 1: To determine if spontaneous DNA damage is increased in mice with major (homozygous mutant) and subtle (heterozygous) genetic defects in two DNA repair pathways crucial for cancer protection (Base Excision Repair, BER, and Nucleotide Excision Repair, NER), and in the corresponding NER deficient human cells. We will use our novel technique to screen and quantify the presence of spontaneous DNA damage in NER defective mice null (xpc-/-) and heterozygous (xpc) for the Xpc gene and in the corresponding human cells (both xpc-/- and xpc). The study will also be extended to mice compromised in BER (oggl-/- and oggl). Aim 2: To further validate and critically test the types of DNA damage detected by our novel technology. To further validate the types of DNA damage detected by our novel technology, we will study synthetic DNA oligonucleotides containing chemically known lesions, at a specific position, as well as yeast strains defective in NER and BER. Finally, we will use a reported assay (QPCR) to measure the levels of spontaneous DNA damage in the NER- and BER- mutant mice. Data derived from these experiments will provide solid validation for the quantitative and qualitative detection capacity of our technology. Our studies have the potential to improve knowledge of the causes, risk factors, diagnosis, prevention and treatment of cancer using innovative methods. In the future, several other potential uses for our DNA damage detection assay can be anticipated, including evaluation of dietary or therapeutic approaches to reduce cancer risk.

描述(申请人提供)：我们的长期目标是预防和治疗癌症。在活细胞中，DNA不断受到损伤。保护机制(如DNA修复)使损伤程度保持在较低水平。但仍会出现未修复的损坏。这是一个问题，因为无法修复的损伤可能会导致突变，而某些基因的突变会导致癌症。几份报告表明，目前未发现DNA修复能力细微缺陷的人容易患癌症。不幸的是，目前检测这些人在技术上具有挑战性，因此，这些人仍然没有得到诊断。我们最近开发了一种检测DNA损伤的新技术。这项技术可能被证明不仅对测量DNA损伤水平(从而估计癌症风险)有用，而且还可以估计每个人的修复能力。在目前的提案中，我们有两个具体的目标：目标1：确定在对癌症保护至关重要的两条DNA修复途径(碱基切除修复，BER和核苷酸切除修复，NER)以及相应的NER缺陷的人类细胞中，具有主要(纯合突变)和微小(杂合)遗传缺陷的小鼠的自发DNA损伤是否增加。我们将使用我们的新技术来筛选和量化NER缺陷小鼠中XPC基因缺失(XPC-/-)和杂合(XPC)以及相应的人类细胞(XPC-/-和XPC)中自发DNA损伤的存在。这项研究还将扩展到BER受损的小鼠(Oggl-/-和Oggl)。目的2：进一步验证和关键测试我们的新技术检测到的DNA损伤类型。为了进一步验证我们的新技术检测到的DNA损伤类型，我们将研究合成DNA寡核苷酸，这些DNA寡核苷酸包含特定位置的化学已知损伤，以及在NER和BER方面存在缺陷的酵母菌株。最后，我们将使用一种已报道的分析(QPCR)来测量NER和BER突变小鼠的自发DNA损伤水平。来自这些实验的数据将为我们技术的定量和定性检测能力提供坚实的验证。我们的研究有可能利用创新的方法提高对癌症的病因、风险因素、诊断、预防和治疗的知识。在未来，我们的DNA损伤检测分析的其他几个潜在用途是可以预期的，包括评估降低癌症风险的饮食或治疗方法。