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（由申请人提供）：多形性胶质母细胞瘤（GBM）仍然是最致命的脑癌，迫切需要更好地定义调节 GBM 恶性特征的分子途径，特别是其侵袭性和神经胶质瘤的持续性。干细胞（GSC），也称为肿瘤增殖细胞，由于其致瘤潜力和治疗耐药性，被认为是肿瘤复发的主要来源。轴突引导受体最初被确定为神经胶质瘤中高度上调的基因。我们最近的患者数据库分析发现，Plexin-B2 的上调与神经胶质瘤分级和不良生存率相关，这促使我们研究这一重要联系的机制基础。 ATCC 神经胶质瘤细胞系表明，Plexin-B2 激活可改变肌动蛋白细胞骨架，并通过激活 Rho GTPases 促进细胞迁移。在颅内移植中，Plexin-B2 shRNA。我们新的初步数据敲除阻碍了侵袭并破坏了神经胶质瘤血管化。我们对患者来源的 GSC 系进行的新初步数据敲除表明，除了前移作用外，Plexin-B2 还可能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。基于这些令人兴奋的结果，我们建议测试 Plexin-B2 在促进神经胶质瘤侵袭和干细胞特征方面发挥多方面作用的中心假设，以促进我们的研究，我们采用了 CRISPR。基因编辑技术在患者来源的 GSC 系中产生 Plexin-B2 双等位基因突变。在目标 1 中，我们关注神经胶质瘤侵袭，并通过进行培养测定来探究 Plexin-B2 信号传导是否影响 GBM 细胞的细胞骨架动力学和细胞运动。通过比较 GSC 及其分化后代的细胞迁移，这组研究还探讨了迁移潜力是否取决于分化等级。 2，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志物表达、自我更新能力、增殖和分化潜力以及治疗抵抗力。在目标 3 中，我们关注的是 Plexin-B2 信号传导的功能靶标和下游效应子，以介导迁移和干细胞特性。 Plexin-B2 是主要的信号臂，细胞迁移是否是通过 Rho GTPases 的调节介导的，STAT3 是否作为核心信号中枢发挥作用，以及干细胞因子 SOX2 或 OLIG2 是否在 STAT3 下游发挥作用以维持干性。粘附分子 L1CAM 和钙粘蛋白/原钙粘蛋白，这是我们最近对 Plexin-B2 敲除的 RNA-Seq 分析中鉴定出的最显着调控的基因组GSC. 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靶点开辟可能性。