Role of NKCC1 on Brain Tumor Stem Cell Migration After EGF and Slit-2 Stimulation

描述(申请人提供)：多形性胶质母细胞瘤(GBM)是最常见和最具破坏性的颅内恶性肿瘤，占所有原发脑肿瘤的20%，中位生存期仅为14个月。癌细胞通常扩散到远离原发肿瘤的地方，个别胶质瘤细胞从肉眼肿瘤转移到周围的实质，使得完全手术切除几乎是不可能的。恶性胶质瘤的这种迁移能力是对任何潜在治疗方法的最大挑战，尽管手术、化疗和放射治疗取得了进展，剩余的侵袭细胞的生长导致了99%的复发率。究竟是什么调节了脑瘤细胞的迁移能力，目前还不完全清楚，还需要研究。这项建议的主要目的是了解已知的促迁移信号，如表皮生长因子(EGF)和Sit蛋白与细胞体积调节之间的联系。EGF和Sit蛋白可能通过Akt途径调节GBM来源干细胞的侵袭和迁移能力，进而调节离子共转运蛋白NKCC1的激活。我们建议使用各种细胞迁移分析和测量细胞内阴离子浓度来研究导致迁移细胞主导过程延长的侵袭模式和细胞体积变化。这项工作的结果将有助于我们了解参与激活脑瘤细胞迁移的级联机制的下游信号通路。此外，这些知识无疑将导致更好的治疗方案，而不是目前这种毁灭性疾病的次佳治疗方案。 公共卫生相关性：多形性胶质母细胞瘤(GBM)是最常见和破坏性最大的原发恶性肿瘤。本课题旨在研究GBM来源的脑肿瘤干细胞(BTSC)的迁移。BTSCs被认为是维持大部分肿瘤并导致手术切除后复发的原因，然而，调控其迁移的分子机制尚不清楚。在这项研究中，我们建议了解亲迁移信号在脑肿瘤侵袭中的作用，以增加有效的靶点来防止脑肿瘤的扩散。

DESCRIPTION (provided by applicant): Glioblastoma multiforme (GBM), the most common and devastating intracranial malignant tumor accounts for 20% of all primary brain tumors and has a median survival rate of only 14 months. Cancer cells often disseminate far from primary tumors and individual glioma cells migrate from the gross tumor into the surrounding parenchyma, making complete surgical resection nearly impossible. This migratory capacity of malignant gliomas represents the greatest challenge to any potential therapy in spite of advances in surgery, chemotherapy and radiotherapy and growth of the remaining invasive cells leads to a recurrence incidence of 99%. What exactly regulates the migratory capacity of brain tumor cells is not fully understood and need to be studied. The main goal of this proposal is to understand the link between known pro- migratory signals such as epidermal growth factor (EGF) and Slit proteins with cell volume regulation. EGF and Slit proteins may play an important role in the modulation of invasive and migratory ability of GBM derived stem cells through Akt pathway that in turn regulates the activation of ion cotransport NKCC1. We propose to study invasive patterns and cell volume changes resulting in the extension of a leading process of a migrating cell, using various cell migration assays and measuring intracellular anion concentration. The results obtained from this work will help us understand the downstream signaling pathways involved in the activation of cascade mechanism responsible for brain tumor cell migration. Further, such knowledge will undoubtedly result in better therapeutic alternatives to current sub-optimal treatments for this devastating disease. PUBLIC HEALTH RELEVANCE: Glioblastoma multiforme (GBM) is the most common and devastating primary malignant tumor. Our project aims to study the migration of GBM-derived Brain Tumor Stem Cells (BTSCs). BTSCs are thought to be responsible for maintaining the bulk of the tumor and to induce recurrence after surgical resection, nevertheless the molecular mechanisms that regulate their migration are not known. In this study, we propose to understand the role of pro-migratory signals in brain tumor invasion in order to increase the available targets to prevent brain tumor dispersal.