CORE--CHEMOTHERAPY

利用大肠杆菌PNP进行基因治疗的策略是至关重要的 在活体内得到证实。这一目标将通过(1)建立 几种合适的体内肿瘤模型，(2)选择合适的 通过毒性和药代动力学评价核苷类似物，以及(3) 展示部分核苷类似物的抗癌活性 肿瘤模型和优化这一活动。第一，在体内的生长 体外转导PNP基因的肿瘤(由Dr. UAB的Sorscher)将被描述为。阿司匹林的体内稳定性 转导也将被确定。将被研究的肿瘤株 是人D-54 mg胶质瘤、大鼠RT-2胶质瘤、小鼠MT-539M6胶质瘤、小鼠 B16黑色素瘤和小鼠16/C乳腺癌。体内生长 在体外转导了报告基因的肿瘤(由 Sorscher博士)也将被刻画出来进行比较。所有增长数据 将与未转导的亲本肿瘤细胞系的结果进行比较。 核苷类似物的血浆药代动力学研究 相应的嘌呤将在单次静脉注射或静脉注射后确定。 核苷的含量。还将确定核苷的MTD和 使用适当的治疗方案，这将取决于 核苷的血浆药代动力学及体内稳定性 转导的PNP基因。如果发现核苷类似物及其嘌呤 要有相似的MTDS，那么这个核苷/嘌呤对将不会用于 抗肿瘤评估。三、精选的抗癌活性 核苷类似物(注射或静脉注射)将根据SC进行评估 转导PNP基因的移植瘤系。为了进行比较， 还将对转导了A基因的肿瘤细胞株进行评估 报告基因和非转导亲本肿瘤细胞系。这个 L或其他2个转导肿瘤将重复抗癌评估 行集合(如果可用)。详细的研究以优化和表征 核苷类似物的抗癌活性(例如， 给药、治疗计划、所需转导细胞的百分比 活动等)将使用最好的模型进行。抗癌药物 用PNP基因治疗观察到的活性将与 用标准临床试剂观察相应的非换能器 肿瘤(使用我们的历史数据库)。

It is essential that the strategy for gene therapy using E. coli PNP be demonstrated in vivo. This goal will be accomplished by (1) establishing a few appropriate in vivo tumor models, (2) selecting appropriate nucleoside analogs by toxicity and pharmacokinetic evaluations, and (3) demonstrating anticancer activity of selected nucleoside analogs in the tumor models and optimizing this activity. First, the in vivo growth of tumors transduced in vitro with the PNP gene (to be supplied by Dr. Sorscher of UAB) will be characterized. The in vivo stability of the transduction will also be determined. The tumor lines that will be studied are human D-54MG glioma, rat RT-2 glioma, murine MT-539M6 glioma, murine B16 melanoma, and murine 16/C mammary adenocarcinoma. The in vivo growth of the tumors transduced in vitro with a reporter gene (to be supplied by Dr. Sorscher) will also be characterized for comparison. All growth data will be compared with that for the nontransduced parental tumor line. Second, the plasma pharmacokinetics of a nucleoside analog and its corresponding purine will be determined after a single iv or ip injection of the nucleoside. An MTD will be also determined for the nucleoside and its purine using an appropriate treatment regimen, which will depend on the plasma pharmacokinetics of the nucleoside and the in vivo stability of the transduced PNP gene. If a nucleoside analog and its purine are found to have similar MTDs, then this nucleoside/purine pair will not be used in antitumor evaluations. Third, the anticancer activity of the selected nucleoside analog (administered ip or iv) will be evaluated against a Sc implanted tumor line transduced with the PNP gene. For comparison, the evaluation will also be conducted with the tumor line transduced with a reporter gene and with the nontransduced parental tumor line. The anticancer evaluations will be repeated with l or 2 other transduced tumor line sets if available. Detailed studies to optimize and characterize the anticancer activity of the nucleoside analog (e.g., route of administration, treatment schedule, percent of transduced cells required for activity, etc.) will be conducted using the best model. The anticancer activity observed with the PNP gene therapy will be compared with that observed with standard clinical agents for the corresponding nontransduced tumor (using our historical data base).