Protein homeostasis dysfunction in LM and VM pathobiology and therapeutic responses

LM 和 VM 病理学和治疗反应中的蛋白质稳态功能障碍

基本信息

批准号：
10567637
负责人：
CARRIE J. SHAWBER
金额：
$ 62.34万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-12-15 至 2026-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10567637
关键词：
Affect Animal Model Blood Blood Coagulation Disorders Blood Vessels Bortezomib Cell Death Cell Separation Cell physiology Cell surface Cells Classification Clinical Collaborations Congenital Abnormality Cytoplasm Dangerousness Data Deep Vein Thrombosis Defect Degradation Pathway Development Dose Drug Screening Endosomes Endothelial Cells Equilibrium FDA approved FRAP1 gene Functional disorder Genes Genetic Goals Grant Growth Heart Diseases Hemorrhage Human In Vitro Infection KRAS2 gene KRASG12D Label Lesion Life Link Lymphatic Lymphatic Endothelial Cells Lysosomes MAPK Signaling Pathway Pathway Malignant Neoplasms Medical Morbidity - disease rate PECAM1 gene PI3K/AKT PIK3CA gene PIK3CG gene Pain Pathogenesis Pathogenicity Pathologic Pathology Pathway interactions Patients Pharmaceutical Preparations Phenocopy Principal Investigator Production Proteasome Inhibition Proteasome Inhibitor Protein Biosynthesis Proteins Pulmonary Fibrosis Ras/Raf Reporting Research Risk Role Sepsis Signal Transduction Sirolimus Somatic Mutation Therapeutic Intervention Transgenic Mice Transgenic Organisms Variant Vascular System Venous Venous Malformation Xenograft Model alpelisib cellular engineering clinically relevant efficacy evaluation functional improvement genetic variant improved lymphatic malformations lymphatic vasculature malformation mortality mosaic mouse model multicatalytic endopeptidase complex novel drug class novel therapeutics overexpression partial response programs protein degradation proteostasis response success targeted treatment therapeutic target treatment response

项目摘要

SUMMARY Slow flow vascular malformations, including lymphatic malformations (LMs) and venous malformations (VMs), have been shown to be caused by somatic mutations in genes that hyperactivate the PI3K/mTOR or RAS signaling. LM/VM patients have severe morbidities and even mortality, and there are no FDA-approved treatments. Current therapies provide partial response and are non-curative. There is an urgent need to identify effective, biologically targeted therapeutics. We have discovered protein homeostasis dysfunction in pathogenic endothelial cells (ECs) isolated from LMs (LMECs) and VMs (VMECs). We demonstrate that this dysfunction is downstream of PI3K/mTOR hyperactivation, which results in increased VECADHERIN and CD31 synthesis, cytoplasmic accumulation, and decreased expression at the cell surface. We proposed that the excess of VECADHERIN/CD31 in the cytoplasm overwhelms the proteasome and lysosomal degradation pathways, which in turn perturbs VECADHERIN/CD31 functions essential to the quiescent blood and lymphatic vasculature. Supporting this hypothesis, we identified a novel class of drugs, proteasome inhibitors (PIs) that inhibit proteasome degradation and preferentially target cells with protein homeostasis defects as more efficacious at suppressing LMEC/VMECs growth when compared to currently used therapies. We hypothesize that PI3K hyperactivation induces protein homeostasis defects that contribute to LM/VM pathology and that targeting this dysfunction serves as a new avenue of therapeutic intervention. In Aim 1, we will determine the mechanism by which PIs suppress abnormal LM and VM growth using patient derived LMEC/VMECs with PI3K and/or RAS pathway hyperactivation. Transgenic mouse models that express either PIK3CAH1047 or KRASG12D using EC and LEC specific drivers will be used to assess the efficacy of 2 PIs, oprozomib and bortezomib, with a goal of prioritizing which PI can be repurposed for the treatment of LMs and VMs. In Aim 2, we will determine the role of protein homeostasis dysfunction in VM/LM pathobiology. Primary human ECs that overexpress pathogenic PIK3CA or KRAS variants and patient ECs will be used to understand the consequences and mechanisms by which increased VECADHERIN and CD31 expression and cytoplasmic accumulation overwhelms proteasome and lysosomal degradation pathways. We will also determine if drugs that improve protein degradation can normalize LMEC/VMEC pathology. The goal is to better understand how common pathogenic variants in LM/VMs contribute to their pathogenesis and determine if therapeutics that target protein degradation defects can be repurposed for LM/VM patients.

概括慢流量血管畸形，包括淋巴畸形（LMS）和静脉畸形（VM）已证明是由过度激活PI3K/mTOR或MTOR或 RAS信号传导。 LM/VM患者患有严重的病态甚至死亡率，并且没有FDA批准治疗。当前的疗法提供了部分反应，并且是非疗法的。迫切需要确定有效的生物学靶向治疗剂。我们发现了蛋白质稳态功能障碍从LMS（LMEC）和VMS（VMEC）分离出的致病内皮细胞（ECS）。我们证明了这一点功能障碍是PI3K/MTOR过度激活的下游，这导致立粘蛋白和 CD31合成，细胞质积累和在细胞表面表达降低。我们提出了这一点细胞质中的维卡德蛋白/CD31的过量淹没蛋白酶体和溶酶体降解途径，这又使维卡德蛋白/CD31的功能对静止的血液和淋巴脉管系统。支持这一假设，我们确定了一类新的药物，蛋白酶体抑制剂（PI）抑制蛋白酶体降解并优先用蛋白稳态缺陷靶细胞为与当前使用的疗法相比，更有效地抑制LMEC/VMEC的增长。我们假设PI3K过度激活诱导蛋白质稳态缺陷，导致LM/VM 病理和针对这种功能障碍的病理是治疗干预的新途径。在AIM 1中，我们将确定使用患者衍生的PI抑制异常LM和VM生长的机制具有PI3K和/或RAS途径过度激活的LMEC/VMEC。表达的转基因小鼠模型使用EC和LEC特定驱动程序的PIK3CAH1047或KRASG12D将用于评估2个PI的功效， oprozomib和bortezomib，其目标是优先考虑哪种PI可以重新使用以治疗LMS 和VM。在AIM 2中，我们将确定蛋白质稳态功能障碍在VM/LM病理生物学中的作用。过表达致病性PIK3CA或KRAS变体和患者EC的主要人类EC将用于了解增加维卡德蛋白和CD31表达的后果和机制和细胞质积累淹没了蛋白酶体和溶酶体降解途径。我们也会确定改善蛋白质降解的药物是否可以使LMEC/VMEC病理标准化。目标是更好地了解LM/VM中常见的致病变异如何有助于其发病机理和确定靶向蛋白质降解缺陷的治疗剂是否可以针对LM/VM患者重新使用。