In Vivo Drug Testing of Pediatric CNS Tumors Using Patient Derived Orthotopic Xenograft Models

使用患者来源的原位异种移植模型对儿童中枢神经系统肿瘤进行体内药物测试

• 批准号: 9310234
• 负责人: Xiaonan Li
• 金额: $ 57.87万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-14 至 2018-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9310234
• 关键词: Animals; Biological Assay; Biological Models; Brain; Brain Neoplasms; Breeding; Cancer Etiology; Cancer Patient; Cells; Central Nervous System Neoplasms; Childhood; Childhood Brain Neoplasm; Childhood Central Nervous System Neoplasm; Childhood Glioblastoma; Clinic; Clinical; Clinical Drug Development; Clinical Trials; DNA copy number; Data; Databases; Diffuse intrinsic pontine glioma; Dose; Ensure; Ependymoma; Faculty; Funding Opportunities; Gene Expression; Gene Expression Profiling; Gene Mutation; Glioblastoma; Glioma; Goals; Housing; Human; Image; Implant; In Vitro; Injection of therapeutic agent; Institution; Investigation; Investigational Drugs; Laboratories; Medicine; Modeling; Molecular; Molecular Abnormality; Molecular Target; Mus; NOD/SCID mouse; New Agents; Operative Surgical Procedures; Patients; Pharmaceutical Preparations; Pharmacotherapy; Phenotype; Positioning Attribute; Preclinical Drug Evaluation; Preclinical Testing; Primary Neoplasm; Research; Resistance; SCID Mice; Series; Serum-Free Culture Media; Specimen; System; Techniques; Testing; Time; Transplantation; Treatment Efficacy; Tumorigenicity; Ursidae Family; Xenograft Model; Xenograft procedure; animal facility; base; cancer stem cell; cancer therapy; cell bank; cell killing; childhood cancer mortality; clinically relevant; cohort; college; cost effective; data mining; drug candidate; drug testing; efficacy evaluation; exome sequencing; experience; implantation; in vivo; medulloblastoma; member; molecular modeling; mouse model; neoplastic cell; new therapeutic target; novel; novel therapeutics; pre-clinical; programs; public health relevance; radioresistant; research clinical testing; response; screening; success; therapeutic evaluation; therapeutic target; tumor; tumor xenograft; tumorigenic

 DESCRIPTION (provided by applicant): This application is prepared in response to the funding opportunity: Pediatric Preclinical Testing Consortium Research Programs (U01), RFA-CA-14-018. Specifically, we propose for Type B: Research Program for tumors of central nervous system (CNS) in vivo testing. Brain tumors are the leading cause of cancer-related death in children. One of the challenges in clinical drug development is how to effectively prioritize drug candidates to ensure clinical success in cancer patients. As pediatric drug candidates are much more numerous than the small number of patients, it is essential to perform comprehensive pre-clinical testing to identify the investigational agents that are most likely to be effective in the clinic. However, such effort has been blocked for many years due to the lack of clinically relevant and molecularly accurate model systems. Fortunately, we have established a large panel (>70) of patient derived orthotopic xenograft (PDOX) models of pediatric brain tumors through direct injection of patient tumor specimens into the brains of SCID mice. These PDOX models are shown to have replicated the histopathological features, invasive phenotypes and major genetic abnormalities (gene expression, DNA copy number and gene mutations) of the original primary tumors even during serial sub-transplantations in vivo in mouse brains. The xenograft tumor cells can also be cryopreserved for sustained and on-demand supply of tumorigenic PDOX cells. This capacity combined with our optimized surgical procedure, with which we can implant up to 260 mice per day, makes it possible for us to test multiple (e.g., 6-10) drugs per year for every tumor type. Our objective is therefore to make use of this unique panel of PDOX models to examine therapeutic efficacy of new agents and to analyze mechanisms of action and therapy resistance in high grade glioma, medulloblastoma and ependymoma. Our hypothesis is that these patient-specific PDOX tumors will respond to anti-cancer therapies similarly to the corresponding human primary tumors, and the effective agents identified through this system would have better chances of clinical success. To test this hypothesis, we will perform a series of in vitro and in vivo assays to achieve the following aims: 1) to identify genetically accurate candidate PDOX models that bear the therapeutic target(s) of new investigational drugs through data mining of our mouse model molecular characterization databases; 2) to select the most responsive models through functional in vitro screening to determine time- and dose- responses; 3) to demonstrate therapeutic efficacy of new investigational drugs in multiple target-bearing PDOX models; and 4) to perform detailed analysis of cellular and molecular mechanisms of cell killing as well as the causes of therapy resistance both in vitro and in vivo. Our novel panel of PDOX mouse models represents a broad spectrum of genetic abnormalities of pediatric CNS tumors. All the assays are well established and routinely performed in our laboratory; we are uniquely positioned to accomplish the proposed drug studies in vivo. Our findings should provide strong preclinical evidence to support the initiation of clinical trials.

 描述（由申请人提供）：本申请是为了响应资助机会而编写的：儿科临床前试验联盟研究项目（U 01），RFA-CA-14-018。具体而言，我们建议B型：中枢神经系统（CNS）肿瘤体内试验研究项目。脑肿瘤是儿童癌症相关死亡的主要原因。临床药物开发的挑战之一是如何有效地优先考虑候选药物，以确保癌症患者的临床成功。由于儿科候选药物的数量远远多于少数患者，因此必须进行全面的临床前试验，以确定最有可能在临床上有效的研究药物。然而，由于缺乏临床相关和分子精确的模型系统，这种努力多年来一直受阻。幸运的是，我们通过将患者肿瘤标本直接注射到SCID小鼠的脑中，建立了一个大的（>70）组的儿童脑肿瘤的患者来源的原位异种移植（PDOX）模型。这些PDOX模型显示出复制了原始原发性肿瘤的组织病理学特征、侵袭性表型和主要遗传异常（基因表达、DNA拷贝数和基因突变），甚至在小鼠脑中的体内连续亚移植期间也是如此。异种移植肿瘤细胞也可以冷冻保存以持续和按需供应致瘤性PDOX细胞。这种能力与我们优化的手术程序相结合，我们每天可以植入多达260只小鼠，使我们能够测试多种（例如，6-10）药物每年每种肿瘤类型。因此，我们的目标是利用这一独特的PDOX模型来检查新药物的治疗效果，并分析高级别胶质瘤、髓母细胞瘤和室管膜瘤的作用机制和治疗抗性。我们的假设是，这些患者特异性PDOX肿瘤对抗癌治疗的反应与相应的人类原发性肿瘤相似，通过该系统鉴定的有效药物将有更好的临床成功机会。为了验证这一假设，我们将进行一系列体外和体内测定以实现以下目的：1）通过我们的小鼠模型分子表征数据库的数据挖掘来鉴定携带新的研究药物的治疗靶标的遗传上准确的候选PDOX模型; 2）通过功能性体外筛选来选择最响应的模型以确定时间和剂量响应; 3）在多靶点PDOX模型中证明新研究药物的疗效; 4）对细胞杀伤的细胞和分子机制以及体外和体内治疗耐药的原因进行详细分析。我们的新型PDOX小鼠模型组代表了儿科CNS肿瘤的广泛遗传异常。所有试验均已在我们实验室建立并常规进行;我们具有独特的优势来完成拟定的体内药物研究。我们的研究结果应提供强有力的临床前证据，以支持临床试验的启动。