Analysis of E-selectin Ligands of Human Acute Leukemia Cells and their Biology in Leukemogenesis

人急性白血病细胞E-选择素配体分析及其在白血病发生中的生物学作用

基本信息

批准号：
9979808
负责人：
Constantine S. Mitsiades
金额：
$ 61.39万
依托单位：
FLORIDA INTERNATIONAL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-17 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9979808
关键词：
AML1-ETO fusion protein Acute leukemia Adhesions Anabolism Antigen-Presenting Cells Automobile Driving Binding Biochemical Biological Assay Biology Blood Blood Cells Blood Vessels Bone Marrow CD34 gene Cell Proliferation Cell Surface Proteins Cell Survival Cell surface Cells Cellular biology Characteristics Custom Cytogenetics Data Distal E-Selectin Endothelial Cells Epitopes Event Expression Profiling Flow Cytometry Genetic Genetic Transcription Glycobiology Glycoconjugates Glycolipids Glycoproteins Glycosyltransferase Gene Golgi Apparatus Growth Hematology Hematopathology Hematopoiesis Hematopoietic Hematopoietic Stem Cell Transplantation Hematopoietic stem cells Home environment Homing Human In Vitro Inflammatory Interleukin-1 Interruption Investigation Laboratories Lectin Lesion Leukemic Cell Leukocytes Licensing Ligands Ligation Link Lipids Liquid substance MLL-AF9 Malignant - descriptor Marrow Measures Mediating Mesenchymal Stem Cells Metabolic Methods Modification Molecular Monitor Mus Neoplasm Metastasis Pathologic Patients Pattern Play Polysaccharides Process Proliferating Proteins Quantitative Reverse Transcriptase PCR Recovery Research Project Grants Resistance Rest Reverse Transcriptase Polymerase Chain Reaction Role SELE gene Scaffolding Protein Scientist Shapes Signal Transduction Signal Transduction Pathway Stratification Structure Surface TNF gene Techniques Transferase Vascular Endothelial Cell Western Blotting acute leukemia cell base cytokine effective therapy experience glycosylation glycosyltransferase in vivo insight lactosamine leukemia leukemogenesis lipid I migration novel strategies outcome forecast overexpression programs receptor recruit scaffold sugar therapy resistant tool transcriptome sequencing

项目摘要

ABSTRACT: The tetrasaccharide known as “sialylated Lewis X” (sLeX; CD15s) is the prototypical binding determinant for E- selectin (CD62E), a Ca++-dependent lectin expressed on vascular endothelial cells. Through investigations described herein, we aim to unveil how this structure, and the underlying glycosyltransferases (GTs) controlling its biosynthesis, mediate(s) human leukemogenesis. The sLeX motif can be presented on cell surfaces on protein (i.e., glycoprotein) and/or lipid (i.e., glycolipid) scaffolds, and these glycoconjugates (known as “E-selectin ligands”) program shear-resistant adhesion to endothelial cells. E-selectin is typically not displayed on resting vascular endothelial cells, and its expression is induced by inflammatory cytokines such as TNF and IL-1. How- ever, conspicuously, E-selectin is constitutively expressed on bone marrow (BM) sinusoidal vessels where it is known to play a key role in mediating migration of circulating cells to BM, a process critical to blood cell recovery following hematopoietic stem cell transplantation (HSCT). Beyond its role in recruiting hematopoietic stem/pro- genitor cells (HSPCs) to BM, it is well-known that E-selectin expression on marrow microvessels serves a fun- damental role in creation of hematopoietic growth-promoting microenvironments, collectively known as “vascular niches”. Studies from our laboratory have shown that human HSPCs express a variety of E-selectin ligands, and we have also observed that leukemic blasts characteristically express E-selectin ligands. We hypothesize that engagement of E-selectin ligands on human acute leukemia cells programs efficient BM metastasis and also enables niche lodgment, serving to displace resident HSPCs from their proper growth microenvironment and thereby promoting leukemic cell proliferation. In this proposal, using E-selectin binding assays under both static and fluid shear conditions, together with complementary techniques in flow cytometry and western blotting, we will analyze the E-selectin binding activity of leukemia cells isolated from blood and BM of patients with acute leukemias. We will identify the pertinent sLeX-bearing glycoconjugates among the different types of human leu- kemia cells, measure the ability of such glycoconjugates to engage E-selectin, and determine how expression of Golgi GTs shape creation of sLeX modifications among the different E-selectin ligands. This information will be integrated with various biochemical approaches including metabolic inhibition of glycosylation and cell surface glycoengineering to custom-modify sLeX display to assess the extent to which sLeX presentation on a specific protein and/or lipid scaffold licenses E-selectin binding among blasts from various subtypes of human acute leukemias, and the impact of the relevant E-selectin receptor/ligand interaction(s) in leukemia cell biology. The results of proposed studies will be key to elucidating the glycobiology of leukemogenesis, and should also pro- vide fundamental insights for establishing novel strategies to treat acute leukemias by selectively interrupting sLeX expression and/or E-selectin ligand-mediated processes, and for potential therapy/prognosis stratification schemas based on sLeX levels and/or the expression of distinct E-selectin ligands on acute leukemia cells. Relevance: Acute leukemia arises because abnormal white cell precursors proliferate within special growth zones within the bone marrow. There is increasing evidence that these growth zones are created by the display of particular sugar molecules on the surface of blood cells that act like Velcro to anchor the cells to marrow vessels. This research project will study these sugar structures and how they are made, with anticipation that information obtained will pave the way for more effective therapies for acute leukemias and may also allow for more precise identification of patients needing more intensive treatment and/or closer monitoring.

抽象的：被称为“唾液酸化 Lewis X”（sLeX；CD15s）的四糖是 E- 的原型结合决定簇。选择素（CD62E），一种在血管内皮细胞上表达的Ca++依赖性凝集素。正如本文所述，我们的目的是揭示这种结构以及潜在的糖基转移酶（GT）如何控制其生物合成介导人类白血病发生 sLeX 基序可以存在于细胞表面。蛋白质（即糖蛋白）和/或脂质（即糖脂）支架，以及这些糖缀合物（称为“E-选择素”）配体”）程序对内皮细胞的抗剪切粘附通常不会在静息时表现出来。血管内皮细胞，其表达由 TNF 和 IL-1 等炎症细胞因子诱导。值得注意的是，E-选择素在骨髓 (BM) 窦状血管上持续表达已知在介导循环细胞向 BM 迁移中发挥关键作用，这是血细胞恢复的关键过程造血干细胞移植（HSCT）后，除了其在招募造血干细胞/原细胞方面的作用。众所周知，E-选择素在骨髓微血管上的表达发挥着重要作用。在促进造血生长的微环境（统称为“血管”）的创建中发挥着重要作用我们实验室的研究表明，人类 HSPC 表达多种 E-选择素配体，并且我们还观察到白血病母细胞特征性地表达 E-选择素配体。 E-选择素配体与人急性白血病细胞的结合可实现有效的骨髓转移实现利基定位，有助于将常驻 HSPC 移出其适当的生长微环境，在此建议中，使用E-选择素结合测定从而在两种静态下促进白血病细胞增殖。和流体剪切条件，以及流式细胞术和蛋白质印迹的补充技术，我们将分析从急性白血病患者的血液和骨髓中分离的白血病细胞的 E-选择素结合活性我们将鉴定不同类型的人类白细胞中相关的 sLeX 糖缀合物。 kemia 细胞，测量此类糖缀合物与 E-选择素结合的能力，并确定表达方式高尔基 GT 的形状在不同 E-选择素配体之间形成 sLeX 修饰。与各种生化方法相结合，包括糖基化和细胞表面的代谢抑制糖工程定制修改 sLeX 显示，以评估 sLeX 在特定情况下呈现的程度蛋白质和/或脂质支架允许E-选择素在来自人类急性白血病不同亚型的原始细胞中结合白血病，以及相关 E-选择素受体/配体相互作用对白血病细胞生物学的影响。拟议研究的结果将是阐明白血病发生的糖生物学的关键，并且也应该促进为建立通过选择性中断治疗急性白血病的新策略提供基本见解 sLeX 表达和/或 E-选择素配体介导的过程，以及潜在的治疗/预后分层基于 sLeX 水平和/或急性白血病细胞上不同 E-选择素配体表达的方案。相关性：急性白血病的发生是因为异常白细胞前体在特殊生长中增殖越来越多的证据表明这些生长区域是由显示器产生的。血细胞表面的特殊糖分子就像尼龙搭扣一样将细胞固定在骨髓上该研究项目将研究这些糖的结构及其制造方法，预计获得的信息将为更有效的急性白血病治疗铺平道路，也可能允许更准确地识别需要更强化治疗和/或更密切监测的患者。