DNA ADDUCTS FORMED DURING BRAIN TUMOR THERAPY

脑肿瘤治疗过程中形成的 DNA 加合物

• 批准号: 6173807
• 负责人: WILLIAM J BODELL
• 金额: $ 17.88万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6173807
• 关键词: adduct; alkylating agents; analytical chemistry; antineoplastics; antiserum; brain neoplasms; carmustine; chemical conjugate; crosslink; dacarbazine; deoxyguanosine; dosage; drug administration rate /duration; drug administration routes; electrochemistry; high performance liquid chromatography; immunofluorescence technique; immunologic assay /test; laboratory rat; method development; neoplasm /cancer chemotherapy; neoplasm /cancer pharmacology; nuclear magnetic resonance spectroscopy; procarbazine; xenotransplantation

Each year there are approximately 50,000 newly diagnosed brain tumors. Chemotherapy is established to be important in the treatment of newly diagnosed and recurrent brain tumors. Laboratory based studies have established that DNA alkylation plays a key role in the initiation of cellular death by chemotherapeutic agents. In order to achieve a better understanding of this process in brain tumor therapy; we propose to measure the formation of DNA abducts in intracerebral (ic.) Tumors treated with alkylating chemotherapeutic agents currently being evaluated for the treatment of brain tumors. To achieve this goal we propose to Aim 1. Optimize a dissociation enhanced lanthanide fluoroimmunoassay (DELFIA) method fo the quantitatation of O6 -methyldeoxguanosine (O6 -MedG). The levels of N7 -methyldeoxguanosine (N7 - MeG) will be determined by electrochemical detection. We will measure the levels of O6 -MedG and N7 -MeG formed in U-87MG cells grown as ic. Tumors in athymic rats treated with temozolamide (TMZ). In these tumors, we will investigate the relationships between levels of O6 -MedG and N7-MeG formed and route of administration, treatment dose and agent and number of treatments. The levels of these alkylation products formed in the ic. tumors will be compared with the levels formed in the contralateral hemisphere and in normal tissues. These methodologies will provide ea unique approach for preclinical analysis of alkytating chemotherapeutic agents in treatment of brain tumors. Aim 2. We will develop a poly clonal antiserum to the dG-dC crosslink (1- [N3-2'deoxycytidly], 2-[N1-2; -DEOXYGUANOSYL]-Ethane) formed by BCNU. Using this antiserum, we will optimize a DELFIA method for the quantitation of the dG-dC crosslink. Aim 3 Investigate the formation of the dG-dC crosslink, O6-(2-hydroxy ethyl) deoxyguanosine (O6- HOEtdG) and N7 - (2-hydroxy ethyl) deoxyguanosine N7-HOEtG. Athymic rats bearing U-87MG ic. Tumors will be treated with either BCNU SarCNU or mitozolamide. The formation of dG-dC crosslink, O6-HOEtdG and N7-HOEtG will be quantitated. We will examine the relationships between levels of these alkylation products and treatment agent, dose and. Number of treatment. These studies will be the first to investigate the formation of BCNU derived DNA abducts in a ic. Brain tumor model.

每年大约有 50,000 个新诊断的脑肿瘤。 化疗被认为对治疗新诊断和复发性脑肿瘤很重要。 实验室研究已证实 DNA 烷基化在化疗药物引发细胞死亡中发挥着关键作用。 为了更好地理解脑肿瘤治疗中的这一过程；我们建议测量用烷化化疗药物治疗的脑内（ic.）肿瘤中DNA绑架物的形成，目前正在评估其对脑肿瘤的治疗效果。为了实现这一目标，我们提出目标 1。优化 O6 -甲基脱氧鸟苷 (O6 -MedG) 定量的解离增强型稀土荧光免疫分析 (DELFIA) 方法。 N7-甲基脱氧鸟苷（N7-MeG）的水平将通过电化学检测来确定。 我们将测量在 ic 生长的 U-87MG 细胞中形成的 O6 -MedG 和 N7 -MeG 的水平。用替莫唑胺 (TMZ) 治疗的无胸腺大鼠的肿瘤。 在这些肿瘤中，我们将研究形成的O6-MedG和N7-MeG水平与给药途径、治疗剂量和药物以及治疗次数之间的关系。 IC 中形成的这些烷基化产物的水平。 将肿瘤与对侧半球和正常组织中形成的水​​平进行比较。 这些方法将为烷化化疗药物治疗脑肿瘤的临床前分析提供独特的方法。 目标2.我们将开发针对BCNU形成的dG-dC交联（1-[N3-2'脱氧胞苷]，2-[N1-2；-DEOXYGUANOSYL]-乙烷）的多克隆抗血清。使用这种抗血清，我们将优化用于 dG-dC 交联定量的 DELFIA 方法。 目标 3 研究 dG-dC 交联、O6-(2-羟乙基)脱氧鸟苷 (O6-HOEtdG) 和 N7-(2-羟乙基)脱氧鸟苷 N7-HOEtG 的形成。 携带 U-87MG ic 的无胸腺大鼠。肿瘤将用 BCNU SarCNU 或米托唑胺治疗。 将定量 dG-dC 交联、O6-HOEtdG 和 N7-HOEtG 的形成。 我们将研究这些烷基化产物的水平与治疗剂、剂量之间的关系。治疗次数。 这些研究将首次调查 BCNU 衍生 DNA 绑架物在 ic 中的形成。脑肿瘤模型。