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5万例新诊断的脑肿瘤。 化疗被认为是治疗新诊断和复发性脑肿瘤的重要手段。 基于实验室的研究已经确定，DNA烷基化在化疗剂引发细胞死亡中起关键作用。 为了更好地理解脑肿瘤治疗中的这一过程，我们建议测量脑内（IC）中DNA绑架物的形成。目前正在评估用烷化剂化疗剂治疗的肿瘤用于治疗脑肿瘤。为了实现这一目标，我们提出了目标1。 优化了测定O 6-甲基脱氧鸟苷（O 6-MedG）的解离增强镧系荧光免疫分析（DELFIA）方法。 将通过电化学检测法测定N7 -甲基脱氧鸟苷（N7 - MeG）的水平。 我们将测量在IC生长的U-87 MG细胞中形成的O 6-MedG和N7 -MeG的水平。用替莫唑胺（TMZ）处理的无胸腺大鼠中的肿瘤。 在这些肿瘤中，我们将研究形成的O 6-MedG和N7-MeG水平与给药途径、治疗剂量和药剂以及治疗次数之间的关系。 这些烷基化产物在反应器中的含量。 将肿瘤与在对侧半球和正常组织中形成的水平进行比较。 这些方法将为脑肿瘤治疗中烷基化化疗药物的临床前分析提供一种独特的方法。 目标2.我们将研制一种抗BCNU形成的dG-dC交联物（1- [N3- 2 '脱氧胞苷]，2-[N1-2; -脱氧鸟苷]-乙烷）的多克隆抗血清。使用这种抗血清，我们将优化DELFIA方法定量的dG-dC交联。 目的3研究dG-dC交联剂O 6-（2-羟乙基）脱氧鸟苷（O 6- HOEtdG）和N7 -（2-羟乙基）脱氧鸟苷N7-HOEtG的形成。 无胸腺大鼠U-87 MG ic.肿瘤将用BCNU SarCNU或米托唑胺治疗。 将定量dG-dC交联、O 6-HOEtdG和N7-HOEtG的形成。 我们将研究这些烷基化产物的水平与处理剂、剂量和浓度之间的关系。治疗次数。 这些研究将是第一个调查的形成BCNU衍生的DNA绑架在一个ic。脑肿瘤模型。