STEM CELL-BRAIN TUMOR INTERPLAY & IN VIVO PHAGE DISPLAY

描述(由申请人提供)： 这项提议旨在开发脑癌诊断和治疗的创新方法，将神经干细胞(NSC)生物学和体内噬菌体展示技术的优势结合起来。这一建议是基于我们之前的工作，该工作证明了神经干细胞对胶质母细胞瘤脑肿瘤细胞具有显著的、明显的“磁性”吸引力。当神经干细胞被注射到一个大脑半球，而大鼠或人胶质母细胞瘤肿瘤被注射到另一个大脑半球时，神经干细胞穿过中线迁移，直接到达肿瘤肿块。当静脉注射神经干细胞时，它们进入大脑并选择性地靶向肿瘤。神经干细胞甚至附着在正在侵袭正常脑组织过程中的单个肿瘤细胞上。当神经干细胞被设计成输送有毒分子时，肿瘤细胞就被杀死了。新的实验将建立在这些结果的基础上。1.神经干细胞对基因诱导的自然肿瘤的短期和长期影响将被分析，而不仅仅是对移植肿瘤。2.将利用小鼠和人神经干细胞探索最佳的细胞数量和最佳注射途径，包括确定颈动脉途径是否可能比脑内途径或静脉途径更有效。3.作为开发更高灵敏度的诊断程序的一步，为将来用于人类，神经干细胞将被改造为携带允许放射可视化的分子，以便神经干细胞将用于描绘脑部肿瘤肿块的位置、大小和数量。4.作为“原则证明”的模型实验，神经干细胞将通过基因工程合成和释放杀死分裂癌细胞的制剂和/或其他可能诱导癌细胞分化为不再危及生命的稳定、静止的胶质细胞的制剂。5.为了揭示控制神经干细胞和肿瘤细胞之间的“串话”的基本分子和细胞生物学机制，强大的噬菌体展示技术将被用于组织培养和完整的小鼠体内，以确定与神经干细胞受体反应并将神经干细胞吸引到肿瘤上的宿主和肿瘤配体，以及脑肿瘤细胞及其特殊血管上的反向特异性受体，这些受体结合由神经干细胞释放的多肽配体。

DESCRIPTION (provided by applicant): This proposal aims to develop innovative methods for brain cancer diagnosis and therapy that will combine the strengths of neural stem cell (NSC) biology and in vivo phage display technology. The proposal is based on our prior work that demonstrated a remarkable, apparently "magnetic" attraction of NSCs to glioblastoma brain tumor cells. When NSCs were injected into one cerebral hemisphere, and rat or human glioblastoma tumors into the other, the NSCs migrated across the midline and headed directly to the tumor masses. When the NSCs were injected intravenously, they entered the brain and selectively targeted on the tumor. NSCs attached even to single tumor cells which were in the process of invading normal brain tissue. When NSCs were engineered to deliver toxic molecules, tumor cells were killed. New experiments will build on these results. 1. Short- and long-term effects of NSCs will be analyzed on genetically-induced natural tumors, not only on grafted tumors. 2. Optimal cell numbers and optimal route of injection into mice will be explored with mouse and human NSCs, including determination of whether a carotid intra-arterial route might be more effective than intracerebral or intravenous routes. 3. As a step toward development of diagnostic procedures of higher sensitivity, for future use in humans, NSCs will be modified to carry molecules allowing radiological visualization, so that the NSCs will serve to delineate the positions, sizes, and number of tumor masses in the brain. 4. As model "proof-of principle" experiments, NSCs will be engineered genetically to synthesize and release agents that kill dividing cancer cells and/or other agents that may induce cancer cells to differentiate into stable, quiescent glial cells that no longer endanger life. 5. To uncover the basic molecular and cell biological mechanisms controlling the "cross-talk" between NSCs and tumor cells, the powerful phage display technology, which allows identification of ligands and their receptors without preexisting data about their natures, will be used in tissue culture and in intact mice to define host and tumor ligands that react with NSC receptors and attract NSCs to the tumor, as well as the reverse - - specific receptors on brain tumor cells and on their specialized blood vessels that bind peptide ligands released by NSCs.