OXIDIZED DNA BASES AS BIOMARKERS OF TUMOR PROGRESSION

氧化 DNA 碱基作为肿瘤进展的生物标志物

• 批准号: 7359010
• 负责人: Paul Thomas Henderson
• 金额: $ 8.67万
• 依托单位: UNIVERSITY OF CALIF-LAWRNC LVRMR NAT LAB
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7359010
• 关键词: OXIDIZED; DNA; BASES; BIOMARKERS; TUMOR

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. An early theory of carcinogenesis proposes that DNA is damaged by environmental factors, which lead to changes in the DNA code. These changes are called mutations. Once enough mutations accumulate, cells can no longer function properly, and cancer arises. The facts that smoking causes lung cancer, and that sunlight exposure causes skin cancer support this theory. However, such a direct environmental link is not evident for breast cancer in humans. A more recent theory suggests that the metabolism of oxygen produces free radicals that cause carcinogenic DNA damage. In order to validate the latter theory, it is necessary to measure the products of free radical damage in cells. Damage to cells caused by reactive oxygen is called oxidation. In some breast cancers, increased levels of oxidative DNA damage have been associated with tumor progression. However, the most commonly used marker of DNA oxidation, called 8-oxoG, is known to be chemically unstable, and is difficult to measure accurately. Importantly, 8-oxoG is itself easily oxidized to form several secondary oxidation products. We propose to develop new technology that will allow detection of the products in rat and human breast cancer cells. Such an assay can be used as a foundation for making diagnostics for use in future human clinical and epidemiological studies. An additional benefit of these biomarkers will be their eventual application to chemoprevention in animals and humans. AMS is a desirable technique due to its sensitivity and robustness as a method for high-throughput measurement. In comparison, less quantitative MS methods such as FT-MS lack the precision of AMS for routine operations, especially at the expected level of a few DNA adducts per cell. The combination of these two techniques will allow for the fractionation and detection of protein polypeptides at or below attomole levels, which is necessary for small forensic samples. This project is complementary aims to those of Project 3 of the AMS RR grant, particularly with regard to the use of AMS to further understand cancer etiology using DNA-based markers. Progress to date has been presented in the Research Highlights section of the 2006 APR.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子弹和调查员（PI）可能已经从其他NIH来源获得了主要资金，因此可以在其他清晰的条目中代表。列出的机构适用于该中心，这不一定是调查员的机构。癌变的早期理论表明，DNA受环境因素的损害，这导致DNA代码的变化。这些变化称为突变。一旦积累了足够的突变，细胞就无法正常运行，并且会产生癌症。吸烟引起肺癌的事实，阳光暴露会导致皮肤癌支持这一理论。但是，这种直接的环境联系对于人类的乳腺癌并不明显。最近的理论表明，氧的代谢产生引起致癌DNA损伤的自由基。为了验证后一种理论，有必要测量细胞中自由基损害的产物。由活性氧引起的细胞损害称为氧化。在某些乳腺癌中，氧化性DNA损伤水平升高与肿瘤进展有关。但是，已知最常用的DNA氧化标记称为8-oxog，在化学上是不稳定的，难以准确测量。重要的是，8-oxog本身很容易氧化以形成几种二级氧化产物。 我们建议开发新技术，以允许在大鼠和人类乳腺癌细胞中检测产品。这样的测定可以用作制作诊断的基础，以在未来的人类临床和流行病学研究中使用。这些生物标志物的另一个好处将是它们最终应用于动物和人类的化学预防。 由于其灵敏度和鲁棒性是高通量测量方法，因此AMS是一种理想的技术。相比之下，诸如FT-MS之类的定量MS方法较少缺乏常规操作的AM精度，尤其是在每个细胞的几个DNA加合物的预期水平上。这两种技术的组合将允许在attomole水平或低于attomole水平的蛋白质多肽的分离和检测，这对于小的法医样品是必不可少的。该项目是针对AMS RR赠款项目3的互补目标，特别是在使用AMS进一步了解使用基于DNA的标记的癌症病因的方面。 在2006年4月的研究亮点部分中已经提出了迄今为止的进展。