MUTA PROP DNA ADDUCTS DERIV ESTROGENS & ANTIESTROGENS

MUTA PROP DNA 加合物衍生雌激素

• 批准号: 6382256
• 负责人: SHINYA SHIBUTANI
• 金额: $ 17.84万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-13 至 2002-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6382256
• 关键词: DNA damage; adduct; breast neoplasms; carcinogen testing; chemical carcinogen; clinical research; drug screening /evaluation; endometrium; estrogens; female; genetic markers; hormone regulation /control mechanism; human subject; laboratory rat; lymphocyte; mutagen testing; mutagens; neoplasm /cancer genetics; oligonucleotides; tamoxifen

DESCRIPTION: Estrogens and their metabolites have been implicated in the etiology of breast cancer. Tamoxifen is an anti-estrogen that is used in the treatment of breast cancer patients. However, tamoxifen treatment has been associated with endometrial cancer, and has been shown to induce hepatocarcinoma in rodents. The hypothesis driving the proposed research postulates that estrogens and tamoxifen are weak carcinogens in humans, reflecting their ability to form covalent adducts with DNA. The goal of the proposed research is to establish the mutagenic potential of selected tamoxife and estrogen DNA adducts. Oligodeoxynucleotides containing a single defined DN adduct will be prepared from activated forms of estrogens and tamoxifen, or by chemical synthesis. The miscoding properties of these adducts will be quantified. The particular adducts to be studied include estrogen or tamoxifen adducts at the N2 position of Guanine and the N6 position of Adenine, and thes adducts will be generated using various different activated metabolites of estrogen and tamoxifen. Using mammalian DNA polymerases, steady state kinetics will be used to measure frequencies of nucleotide insertion opposite each lesion and chain extension from the 3' terminus. In this way the in vitro miscoding specificity for each adduct will be established. Miscoding propertie will be analyzed under steady-state conditions, using templates with the adducts in different sequence contexts, and using three different mammalian polymerases. Site specifically adducted oligos will also be used to build plasmids in order to establish the miscoding specificity of selected adducts i vivo, in mammalian cells. The proposed experiments are designed to provide quantitative information on the mutagenicity of selected estrogen and anti-estrogen DNA adducts. The tamoxifen DNA adducts prepared for in vitro experiments will also be employed for as standard markers in studies to detect adducts in the DNA of patients undergoing tamoxifen treatment; preliminary studies have established the presence of such adducts in endometrial tissue. Dr. Shibutani will explore the possibility of using the detection of tamoxifen DNA adducts as a biomarker to investigate the relationship between tamoxifen therapy and the development of endometrial cancer.

描述：雌激素及其代谢产物与 乳腺癌的病因。 他莫昔芬是一种抗雌激素， 乳腺癌患者的治疗。 然而，他莫昔芬治疗 与子宫内膜癌有关，并已被证明可诱导 啮齿类动物肝癌。 推动拟议研究的假设 假定雌激素和他莫昔芬是人类的弱致癌物， 反映了它们与DNA形成共价加合物的能力。 的目标 拟议的研究是建立选定的诱变潜力， 他莫昔夫和雌激素DNA加合物。 含a的寡脱氧核苷酸 将从活化形式的雌激素制备单一定义的DN加合物 和他莫昔芬，或通过化学合成。 这些错误编码的属性 加合物将被定量。 待研究的特定加合物包括 雌激素或他莫昔芬加合物在鸟嘌呤的N2位和N6位 腺嘌呤的位置，这些加合物将使用各种方法产生。 雌激素和他莫昔芬的不同活化代谢物。 使用哺乳动物 DNA聚合酶，稳态动力学将用于测量频率 在每个损伤的对面插入核苷酸，并从3'端延伸链， 终点站 以这种方式，每种加合物的体外错误编码特异性 将建立。 错误编码属性将在 稳态条件下，使用模板与加合物在不同的 序列背景，并使用三种不同的哺乳动物聚合酶。 网站 特异性加合的寡核苷酸也将用于构建质粒， 在哺乳动物体内建立所选加合物的错误编码特异性 细胞 拟议的实验旨在提供定量的 选定雌激素和抗雌激素DNA的致突变性信息 加合物 为体外实验制备的他莫昔芬DNA加合物将 也可用作研究中的标准标记物，以检测 接受他莫昔芬治疗的患者的DNA;初步研究 确定了子宫内膜组织中存在这种加合物。 博士 涩谷将探讨使用他莫昔芬检测的可能性 DNA加合物作为生物标志物研究三苯氧胺与肿瘤的关系 治疗和子宫内膜癌的发展。