Plexin-B2 function in glioma invasion and glioma stem cell maintenance

Plexin-B2 在神经胶质瘤侵袭和神经胶质瘤干细胞维持中的功能

基本信息

批准号：
9106872
负责人：
Roland Horst Friedel
金额：
$ 38.32万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-04-01 至 2021-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9106872
关键词：
Actins Address Adopted Biological Assay Brain Brain Neoplasms CRISPR/Cas technology Cadherins Cell Adhesion Molecules Cell Line Cell Maintenance Cell Proliferation Cells Characteristics Clustered Regularly Interspaced Short Palindromic Repeats Corpus Callosum Cues Cytoskeleton DNA Sequence Alteration Data Databases Excision Exhibits Family Gene Targeting Genes Genetic Epistasis Glioblastoma Glioma Growth Guanosine Triphosphate Phosphohydrolases Heterogeneity Human In Vitro Infiltrative Growth Investigation Knock-out Knowledge Link Maintenance Malignant - descriptor Malignant Neoplasms Malignant neoplasm of brain Mediating Migration Assay Modeling Molecular Monomeric GTP-Binding Proteins Mutation Neural Cell Adhesion Molecule L1 Operative Surgical Procedures Pathway interactions Patients Phenotype Pilot Projects Play Primary Brain Neoplasms Property Recurrence Resistance Role SEMA3F gene STAT3 gene Semaphorins Signal Pathway Signal Transduction Slice Source Stem Cell Factor Stem cells Structure Technology Testing Transplantation Treatment Protocols Tumorigenicity Twin Multiple Birth Up-Regulation Vascularization arm axon guidance base cancer stem cell cell growth cell motility cell type cohort combinatorial glioma cell line in vivo insight knock-down member migration mutant neoplastic cell new therapeutic target novel novel marker novel therapeutics outcome forecast overexpression plexin public health relevance radiation resistance receptor receptor binding rho rho GTP-Binding Proteins self-renewal small hairpin RNA stem stem cell niche stemness targeted treatment therapy resistant transcription factor transcriptome sequencing tumor tumor progression tumorigenic

项目摘要

DESCRIPTION (provided by applicant): Glioblastoma multiforme (GBM) remains the most deadly form of brain cancer. There is a dire need to better define the molecular pathways that regulate the malignant features of GBM, in particular, its invasiveness and the persistence of glioma stem cells (GSC), also known as tumor propagating cells, which are thought to be the main source of tumor recurrence due to their tumorigenic potential and therapy resistance. Plexin-B2 is an axon guidance receptor originally identified as a gene highly upregulated in glioma. Our recent patient database analyses found that upregulation of Plexin-B2 correlates with glioma grade and poor survival. This prompted us to investigate the mechanistic basis of this important link. Our studies in human ATCC glioma cell lines demonstrated that Plexin-B2 activation alters actin cytoskeleton and promotes cell migration through activation of Rho GTPases. In intracranial transplants, Plexin-B2 shRNA knockdown hindered invasion and disrupted glioma vascularization. Our new preliminary data from patient-derived GSC lines suggest that besides a promigratory role, Plexin-B2 may also regulate glioma stem cell phenotypes, including stem cell marker expression, self-renewal capacity, proliferation and differentiation potential. Building on these exciting results, we propose to test the central hypothesis that Plexin-B2 plays a multifaceted role in promoting glioma invasion and stem cell characteristics. To facilitate our studies, we have adopted CRISPR gene editing technology to generate bi-allelic mutations of Plexin-B2 in patient-derived GSC lines. In Aim 1, we focus on glioma invasion and ask if Plexin-B2 signaling influences cytoskeletal dynamics and cellular motility of GBM cells by performing culture assays, brain slice cultures, and intracranial transplants. By comparing cell migration of GSCs and their differentiated progeny, this set of studies also addresses whether migratory potential is contingent on differentiation hierarchy. In Aim 2, we focus on glioma stem cell characteristics and ask if Plexin-B2 contributes to stem cell marker expression, self-renewal capacity, proliferation and differentiation potential, and treatment resistance. We will investigate in survival cohorts with GSC intracranial transplants if Plexin-B2 deletion confers survival benefit and if it reduces radiation resistance. In Aim 3, we focus on functional targets and downstream effectors of Plexin-B2 signaling in mediating migration and stem cell properties. We ask which intracellular domain of Plexin-B2 is the main signaling arm, if cellular migration is mediated through modulation of Rho GTPases, whether STAT3 functions as a core signaling hub, and if stem cell factors SOX2 or OLIG2 function downstream of STAT3 for stemness maintenance. Lastly, we will study the adhesion molecules L1CAM and cadherins/protocadherins, the most significantly regulated group of genes that were identified in our recent RNA-Seq analysis of Plexin-B2 knockout GSC. Understanding how Plexin-B2 regulates the malignant features of GBM will open up possibilities for new targets to inhibit glioma growth and invasion.

描述（由适用提供）：多形胶质母细胞瘤（GBM）仍然是脑癌最致命的形式。直接需要更好地定义调节GBM恶性特征的分子途径，特别是其侵入性和神经胶质瘤干细胞（GSC）的持久性（GSC），也称为肿瘤传播细胞，这些细胞被认为是肿瘤复发的主要来源。 Plexin-B2是最初被鉴定为神经胶质瘤高度更新的基因的轴突引导接收器。我们最近的患者数据库分析发现，PLEXIN-B2的更新与神经胶质瘤级相关，生存率差。这促使我们研究了这一重要链接的机械基础。我们在人ATCC胶质瘤细胞系中的研究表明，Plexin-B2激活改变了肌动蛋白的细胞骨架，并通过Rho GTPases的激活促进细胞迁移。在颅内移植中，Plexin-B2 shRNA敲低阻碍了侵袭并破坏了神经胶质瘤血管形成。我们来自患者衍生的GSC系的新的初步数据表明，除了承诺作用外，Plexin-B2还可以调节神经胶质瘤干细胞表型，包括干细胞标记物表达，自我更新能力，增殖和分化潜力。在这些令人兴奋的结果的基础上，我们建议测试中心假设，即plexin-b2在促进神经胶质瘤侵袭和干细胞特征方面起着多方面的作用。为了支持我们的研究，我们采用了CRISPR基因编辑技术来在患者衍生的GSC系列中生成Biallalic B2的双行突变。在AIM 1中，我们专注于神经胶质瘤侵袭，并询问Plexin-B2信号传导是否通过进行培养评估，脑切片培养和颅内移植物来影响GBM细胞的细胞骨架动力学和细胞运动。通过比较GSC的细胞迁移及其分化后代，这组研究还解决了迁移潜力是否取决于分化层次结构。在AIM 2中，我们关注神经胶质瘤干细胞特征，并询问Plexin-B2是否有助于干细胞标记物表达，自我更新能力，增殖和分化潜力以及治疗耐药性。如果plexin-b2缺失承认生存益处并降低了辐射耐药性，我们将与GSC内颅内移植的生存队列进行研究。在AIM 3中，我们专注于Plexin-B2信号传导在介导迁移和干细胞特性中的功能靶标和下游效应。我们询问plexin-B2的哪个细胞内结构域是主要的信号传导臂，如果通过调节Rho GTPases介导细胞迁移，STAT3是否充当核心信号枢纽，以及是否介导了STAT3的STAT3的干细胞因子SOX2或OLIG2在STAT3的下游功能。最后，我们将研究粘附分子L1CAM和钙粘蛋白/原钙粘着蛋白，这是我们最近对Plexin-B2敲除GSC的RNA-SEQ分析中鉴定出的最显着调节的基因组。了解Plexin-B2如何调节GBM的恶性特征将为抑制神经胶质瘤生长和侵袭的新目标打开可能性。