Glioblastoma stem cells therapy

描述(申请人提供)：胶质瘤约占所有原发中枢神经系统肿瘤的60%。胶质母细胞瘤(GBM)或IV级胶质瘤是恶性程度最高的肿瘤，占所有胶质瘤的50.9%。胶质母细胞瘤是高度异质性的肿瘤，肿瘤内不同类型的肿瘤细胞和间质细胞之间存在复杂的相互作用。最近有研究表明，大多数肿瘤细胞没有能力重塑原始肿瘤的表型，而在裸鼠异种移植后，肿瘤中只有一小部分细胞具有这种能力，这种细胞被称为肿瘤干细胞。与非癌症干细胞相比，这些癌症干细胞似乎对化疗和放射等传统疗法更具抵抗力。根据目前对高级别胶质瘤的治疗，大多数患者在一年内死于在切除区域一厘米内形成的新的继发性肿瘤灶。这些病灶富含癌症干细胞，很可能是导致肿瘤复发的原因。我们的建议侧重于寻找能够提高对GBM干细胞的治疗效果的小分子药物。肿瘤坏死因子相关的凋亡诱导配体(TRAIL)被认为是一种潜在的抗癌药物。然而，相当数量的不同类型的癌细胞，包括基底膜，对TRAIL诱导的细胞凋亡具有抵抗力。我们计划确定候选药物，既可以直接杀死原代GBM干细胞，也可以使这些细胞对TRAIL诱导的细胞凋亡敏感。我们将使用我们开发的基于自然分泌的Gaussia荧光素酶的高通量细胞凋亡筛选方法，并筛选不同的小分子文库，包括包含FDA批准的跨越血脑屏障的药物的小分子文库。我们将在我们的实验性胶质瘤干细胞-生物发光模型中验证最有希望的药物命中。公共卫生相关性：本提案中概述的工作的目的是使用自然分泌的Gaussia荧光素酶作为高通量筛选的报告，以确定新的胶质母细胞瘤干细胞疗法。候选药物将在培养中以剂量和时间依赖的方式进行验证，以及在我们体内的实验性胶质母细胞瘤干细胞-生物发光模型中进行验证。

DESCRIPTION (provided by applicant): Gliomas account for about 60% of all primary CNS tumors. Glioblastoma (GBM) or grade IV gliomas which comprise 50.9% of all gliomas are the most malignant form. Glioblastoma tumors are highly heterogeneous and there is a complex interaction among different types of tumor cells and stromal cells within the tumor. Recently it has been shown that the majority of tumor cells do not have the capacity to recapitulate a phenocopy of the original tumor and that only a small subpopulation of cells in the tumor, called cancer stem cells, have that ability upon xenotransplantation in nude mice. These cancer stem cells appear to be more resistant to conventional therapy, like chemotherapy and radiation, as compared to the non-cancer stem cells. Following current therapy for high-grade glioma tumors, most patients die within a year from a new secondary tumor foci forming within one centimeter of the resected area. These foci are enriched for cancer stem cells, and it is likely that they are responsible for tumor recurrence. Our proposal focuses on identifying small molecule drugs which can increase therapeutic efficacy for GBM stem cells. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is regarded as a potential anti-cancer agent. However, a considerable number of different types of cancer cells, including GBM, are resistant to apoptosis induction by TRAIL. We plan to identity drug candidates which either kill primary GBM stem cells directly or can sensitize these cells to TRAIL-induced apoptosis. We will use a high throughput apoptosis-screening assay which we have developed based on the naturally secreted Gaussia luciferase and screen different small molecule libraries including ones containing FDA-approved drugs which crosses the blood-brain barrier. We will validate the most promising drug hits in our experimental glioma stem cells-bioluminescent model in vivo. PUBLIC HEALTH RELEVANCE: The purpose of the work outlined in this proposal is to use the naturally secreted Gaussia luciferase as a reporter for high throughput screening in order to identify novel glioblastoma stem cells therapeutics. The drug candidates will be validated in dose- and time-dependent manner in culture as well as in our experimental glioblastoma stem cells-bioluminecence model in vivo.