Altered miRNA Expression Drives Proliferation of Lymphatic Malformation by Activating Pro-Growth Signaling Cascades

改变的 miRNA 表达通过激活促生长信号级联驱动淋巴畸形的增殖

基本信息

批准号：
10677332
负责人：
Ravi Sun
金额：
$ 3.8万
依托单位：
ARKANSAS CHILDREN'S HOSPITAL RES INST
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-25 至 2027-08-24
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10677332
关键词：
Anatomy Angiopoietin-2 Automobile Driving Biological Assay Biology Blood Blood Vessels Cell Proliferation Cell physiology Complex Data Set Dermal Development Down-Regulation Endothelial Cells Environment Excision Exclusion Functional disorder Goals Growth Growth Factor Homeostasis Human Infiltration Inflammation Integrins Investigation Laboratories Lesion Life Liposomes Lymphangiogenesis Lymphatic Lymphatic Endothelial Cells Lymphatic Metastasis Mediating Mediator Mentors Messenger RNA MicroRNAs Molecular Molecular Biology Morbidity - disease rate Multiomic Data Mutation Nuclear Operative Surgical Procedures Outcome PIK3CA gene PIK3CG gene Pain Pathogenesis Pathway interactions Permeability Phenotype Phosphorylation Physicians Plasmids Play Proliferating Proteins Proteomics Receptor Protein-Tyrosine Kinases Recurrence Regulation Role Scientist Sclerotherapy Signal Transduction Sirolimus Small Interfering RNA Structure Systems Biology Testing Therapeutic Training Transfection Tube Up-Regulation Vascular Endothelial Cell Vascular Permeabilities Western Blotting alpelisib cadherin 5 career clinical practice congenital anomaly differential expression gain of function gain of function mutation immunocytochemistry improved inhibitor insight knock-down lymphatic development lymphatic malformations lymphatic vessel mRNA sequencing migration multidisciplinary multiple omics mutant new therapeutic target novel overexpression pharmacologic posttranscriptional primary lymphedema protein expression targeted treatment therapeutic target transcription factor translational medicine

项目摘要

PROJECT SUMMARY/ABSTRACT Lymphatic malformations (LMs) are complex congenital lesions composed of dilated, abnormal lymphatic channels that can result in life-threatening morbidity due to their propensity to enlarge, encroach on nearby anatomical structures, become infected, and cause significant pain and disfigurement. Although somatic, gain- of-function mutations in the PIK3CA gene have been identified in LM endothelial cells (LM-ECs) and are thought to drive aberrant lymphangiogenesis through overactivation of the PI3K/Akt pathway, the mechanisms underlying many phenotypic abnormalities apparent in LMs, such as abnormal vessel formation and permeability, are not fully understood. Considering the significant complications and recurrence rates of traditional treatments for LMs, greater insight into the molecular mechanisms underlying LM pathogenesis is needed to identify novel therapeutic targets and develop improved molecular therapies. Angiopoietin-2 (Ang-2) is a vascular growth factor that plays a critical role in lymphatic development and homeostasis; however, its functions in LMs are unknown. Utilizing a multi-omics approach (miRNA-seq, mRNA-seq, proteomics) to generate a comprehensive network of miRNA-mRNA-protein expression in LM-ECs with gain-of-function PIK3CA mutations compared to normal human dermal lymphatic endothelial cells, we have identified significant downregulation of Ang-2 mRNA and protein in LM-ECs in parallel with significant upregulation of miRNAs in LM-ECs that are predicted post- transcriptional suppressors of Ang-2, yet their function in LM-ECs is unknown. Ang-2 is also downregulated in PIK3CA-mutant blood endothelial cells through Akt-mediated inactivation of its transcription factor, Forkhead box O1. Ang-2 expression can be rescued with PI3K pathway inhibitors; however, this mechanism has not been demonstrated in LMs. Considering the critical role of Ang-2 in lymphatic endothelial cell function, we hypothesize that alternations in Ang-2 expression in LM-ECs drive their abnormal lymphangiogenic phenotype and may be a viable therapeutic target. This hypothesis will be tested with the following specific aims: (1) define the regulatory mechanisms driving differential expression of Ang-2 in LM-ECs and (2) define the impact of aberrant Ang-2 expression on LM-EC proliferation, migration, tube formation, and permeability. This proposal will be the first investigation into the regulation and function of Ang-2 in LMs, potentially uncovering novel mechanisms underlying the pathogenesis of LMs and lymphatic and vascular endothelial cell dysfunction which may improve clinical practice and thus has significant relevance to the field of vascular biology. The overarching goal of this proposal is to identify suitable targets for the development of deliverable, molecular therapeutics. The ACRI Vascular Anomalies Laboratory provides an exceptional training environment, and we have assembled a mentoring team of leaders in vascular anomalies, systems biology, and translational medicine that will facilitate this unique and rigorous training, with the principal goal of preparing for a successful career as an independent physician scientist.

项目概要/摘要淋巴管畸形 (LM) 是一种复杂的先天性病变，由扩张、异常的淋巴管组成由于它们倾向于扩大、侵犯附近区域，可能导致危及生命的发病率解剖结构，被感染，并导致严重的疼痛和毁容。虽然是肉体的，但增益- PIK3CA 基因的功能性突变已在 LM 内皮细胞 (LM-EC) 中被发现，并被认为通过 PI3K/Akt 通路的过度激活来驱动异常的淋巴管生成，其潜在机制 LM 中明显的许多表型异常，例如异常的血管形成和渗透性，并不是完全明白了。考虑到传统治疗 LM 的严重并发症和复发率，需要更深入地了解 LM 发病机制的分子机制来识别新的治疗目标并开发改进的分子疗法。血管生成素-2 (Ang-2) 是一种血管生长因子在淋巴管发育和体内平衡中发挥着关键作用；然而，它在语言模型中的功能尚不清楚。利用多组学方法（miRNA-seq、mRNA-seq、蛋白质组学）生成全面的网络与正常相比，具有功能获得性 PIK3CA 突变的 LM-EC 中 miRNA-mRNA-蛋白表达在人真皮淋巴内皮细胞中，我们发现 Ang-2 mRNA 显着下调，并且 LM-EC 中的蛋白质与 LM-EC 中 miRNA 的显着上调同时发生，这是预测的 Ang-2 的转录抑制因子，但其在 LM-EC 中的功能尚不清楚。 Ang-2 也被下调 PIK3CA 突变型血液内皮细胞通过 Akt 介导的转录因子 Forkhead box 失活 O1。 PI3K 通路抑制剂可以挽救 Ang-2 的表达；但这一机制尚未得到落实在 LM 中得到了证明。考虑到 Ang-2 在淋巴管内皮细胞功能中的关键作用，我们假设 LM-EC 中 Ang-2 表达的改变驱动其异常的淋巴管生成表型，并且可能是可行的治疗目标。该假设将通过以下具体目标进行检验：（1）定义监管驱动 LM-EC 中 Ang-2 差异表达的机制，以及 (2) 定义异常 Ang-2 的影响 LM-EC 增殖、迁移、管形成和通透性的表达。该提案将是第一个研究 Ang-2 在 LM 中的调控和功能，可能揭示新机制 LM 的发病机制以及淋巴和血管内皮细胞功能障碍可能会改善临床实践，因此与血管生物学领域具有重要意义。本次活动的总体目标是该提案旨在确定开发可交付的分子疗法的合适靶点。澳大利亚化学研究所血管异常实验室提供了卓越的培训环境，我们组建了一个由血管异常、系统生物学和转化医学领域的领导者组成的指导团队将促进这种独特而严格的培训，其主要目标是为独立的成功职业生涯做好准备医师科学家。