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: 2806097
• 负责人: WILLIAM J BODELL
• 金额: $ 20.98万
• 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/2806097
• 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例新诊断的脑瘤。化疗在新诊断和复发的脑肿瘤的治疗中被证实是重要的。基于实验室的研究已经证实，DNA烷基化在化疗药物启动细胞死亡的过程中起着关键作用。为了在脑肿瘤治疗中更好地理解这一过程，我们建议测量脑内DNA外展的形成。用烷化化疗药物治疗的肿瘤目前正在评估脑肿瘤的治疗。为了实现这一目标，我们提出的目标是：1.优化解离增强稀土荧光免疫分析法(DELFIA)测定O6-甲基脱氧鸟苷(O6-MedG)的方法。N7-甲基脱氧鸟苷(N7-Meg)的水平将通过电化学检测来测定。我们将测量在IC生长的U-87 mg细胞中形成的O6-MedG和N7-Meg的水平。替莫唑胺(TMZ)治疗裸鼠肿瘤。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、治疗剂量和制剂以及治疗次数之间的关系。在IC中形成的这些烷基化产物的水平。肿瘤将与对侧大脑半球和正常组织中形成的水平进行比较。这些方法将为烷基化化疗药物在脑肿瘤治疗中的临床前分析提供独特的方法。目的2.制备针对BCNU形成的DG-DC交联物(1-[N3-2‘脱氧胞苷]，2-[N1-2；-DODOXYGUANOSYL]-乙烷)的多克隆抗血清。利用该抗血清，我们将优化DELFIA定量DG-DC交联物的方法。目的3研究DG-DC交联物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。裸鼠荷瘤U-87 mg ic。肿瘤将接受BCNU、SarCNU或米托唑胺治疗。DG-DC交联物、O6-HOEtdG和N7-HOEtG的形成将被定量。我们将研究这些烷基化产物的水平与处理剂、剂量和。治疗次数。这些研究将是第一次调查BCNU来源的DNA绑架在IC中的形成。脑瘤模型。