Pathway Analysis in Mouse Model for Astrocytoma via Systems Biology Approach

高级别星形细胞瘤是最常见的脑部恶性肿瘤，可供选择的治疗方法有限，而且已被证实与一般较差的临床结果有关。因此，提高对疾病病因学的理解是开发创新诊断和治疗策略的一条很有希望的途径。该项目包括CAPR(Van Dyke博士的临床前研究中心)、UNC(Ryan Miller博士的实验室)和ISB(Leroy Hood博士的实验室)之间广泛的合作努力，以表征星形细胞缺乏症过程中的分子特征和途径，并确定癌症转化和治疗反应的有希望的早期预后标记。为此，该项目利用了小鼠可诱导疾病启动的优势，扰乱和/或监测癌症发生过程的能力，以及无偏见系统生物学方法的广泛力量。随着疾病的进展，各种最先进的分子技术将监测组织和血清中的基因组、转录组、蛋白质组和代谢动力学。在可能的情况下，将利用跨物种数据分析来确定研究结果与人类疾病的相关性。在过去的一年里，CAPR的科学家们开发和优化了育种方法，以保持高级别星形细胞瘤和胶质母细胞瘤的一种可诱导遗传模型的群体。该模型以复杂的遗传结构为特征，将几个突变的等位基因混合在一起，使pRb/p105/p130、K-ras和PTEN/Akt通路单独或以不同的组合出现功能障碍。已经设计并验证了所需的一套分析方法，以快速识别具有所需等位基因组合的单个动物，以及多个基于组织学、分子生物学和活体成像的临床相关终点，以监测疾病进展阶段。例如，CAPR采用了一种升级的方法，允许通过MRI模式同时对多个动物进行成像，从而使整个实验队列的多个纵向成像会话成为可能。在另一系列实验中，CAPR的临床前评估小组开发了一种补充的原位颅内异种移植模型策略，使用了人类胶质瘤细胞系或从新生肿瘤动物中分离的原代AA/GBM细胞，并在体外培养条件下进行最低限度的维持。到目前为止，这些原位模型已被用于几个合作的PK/PD项目，旨在研究通过高通量体外筛选策略确定的纳米技术化合物和候选药物在脑组织中的生物利用度(例如，SchweinFursins，在CCR内部与Karlyne Reilly博士合作，或与台湾CGMH国际合作，以评估超声辅助药物传递策略)。

High grade astrocytomas represent the most common brain malignancies with limited therapeutic options available and proven association with generally poor clinical outcomes. Improved understanding of disease etiology thus represents a promising avenue for developing innovative diagnostic and therapeutic strategies. The project encompases a broad set of collaborative efforts among CAPR (Dr. Van Dyke's Preclinical Research Center), UNC (Dr. Ryan Miller's lab) and ISB (Dr. Leroy Hood's lab) to characterize molecular signatures and pathways underlying the astrocytomagenesis process and to identify promising early prognostic markers of cancerous transformation as well as response to therapeutic treatment. To this end, the project leverages the advantages of inducible disease initiation in the mouse, the ability to perturb and/or monitor the carcinogenesis process, and the extensive power of unbiased systems biology approach. A variety of state-of-the-art molecular technologies will monitor genome, transcriptome, proteome, and metabolom dynamics in tissues and blood serum as the disease progresses. Where possible, a cross-species data analysis will be exploited to determine the relevance of findings to human disease. During the past year, CAPR scientists developed and optimized breeding approaches to maintain the colony of one-of-a-kind inducible genetic model for high-grade astrocytoma and glioblastoma. The model features a complex genetic setup that mingles several mutant alleles to render dysfunctional pRb/p105/p130, K-ras, and PTEN/Akt pathways alone or in different combinations. The required set of assays to rapidly identify individual animals with desired allelic combinations has been designed and validates, along with multiple histology-, molecular biology-, and in vivo imaging-based clinically relevant endpoints to monitor disease progression stage. To exemplify, an upgraded approach allowing simultaneous imaging of multiple animals by MRI modality has been adopted by CAPR making feasible multiple longitudinal imaging sessions of the entire experimental cohort. In another line of experiment, the Preclinical Evaluation group of CAPR has developed a complementary orthotopic intracranial xenograft modelling strategy employing either human glioma cell lines or primary AA/GBM cells isolated from de novo tumor bearing animals and minimally maintained under in vitro culturing conditions. These orthotopic models have been utilized thus far in several collaborative PK/PD projects aimed at bioavailability studies in brain tissue for nanotechnology compounds and drug candidates identified through high-throughput in vitro screening strategies (e.g. Schweinfurthins, in intramural CCR collaboration with Dr. Karlyne Reilly or international collaboration with CGMH, Taiwan, to evaluate ultrasound-assiated drug delivery strategy).