Regulation of transendothelial migration of Tregs in irradiated HNSCCs by EphB4-ephrinB2 interaction

EphB4-ephrinB2 相互作用对受辐射 HNSCC 中 Tregs 跨内皮迁移的调节

基本信息

批准号：
10643984
负责人：
Laurel B Darragh
金额：
$ 4.45万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10643984
关键词：
AKT Signaling Pathway Affect Animal Model Autoimmune Binding Biological Assay Blood Vessels CD4 Positive T Lymphocytes CD8B1 gene Cell Adhesion Cell Communication Cell physiology Cells Coculture Techniques Combination immunotherapy Cytometry Cytoplasmic Tail Data Disease Effector Cell Embryonic Development Endothelial Cells Endothelium EphB4 Receptor Equilibrium FOXP3 gene Failure Flow Cytometry Genetic Genetic Engineering Goals HPV-negative head and neck cancer Head and Neck Cancer Head and Neck Squamous Cell Carcinoma Homing Immune Immune Evasion Immune checkpoint inhibitor Immunocompetent Implant Infiltration L-Selectin Ligands LoxP-flanked allele Malignant Neoplasms Mediating Methods Modeling Molecular Molecular Target Mus Outcome Participant Pathway interactions Patients Peptides Phenotype Phosphorylation Physiological Play Population Pre-Clinical Model Process Proto-Oncogene Proteins c-akt Publishing Radiation therapy Receptor Protein-Tyrosine Kinases Regulation Regulatory T-Lymphocyte Research Resistance Resistance development Role STAT3 gene Signal Transduction Site System T cell differentiation T-Cell Proliferation T-Lymphocyte Testing Tumor Promotion Up-Regulation Vascular Endothelial Cell Vascular Endothelium angiogenesis anti-PD-1 anti-tumor immune response cell motility cell type effective therapy effector T cell high risk immunological status immunoregulation in vivo inhibitor intravital microscopy knock-down migration mouse model novel pharmacologic preclinical study radiation response radioresistant receptor recruit response side effect therapy resistant trafficking transcriptome sequencing tumor tumor growth tumor microenvironment tumor progression tumor-immune system interactions

项目摘要

Abstract Resistance to radiation therapy (RT) remains a challenging problem for high-risk head and neck squamous cell carcinoma (HNSCC) patients. Anti-PD1 is now approved in the first- and second-line settings, indicating that the majority of these tumors are resistant to treatment. The field awaits the results of multiple trials testing whether combining immunotherapy and RT can help avoid resistance to RT, but many preclinical studies (including those from our lab) indicate that treatment resistance still develops despite such combinations. The preferential recruitment of unique immunosuppressive cell subtypes after RT to the tumor microenvironment (TME) in response to RT plays an important role in contributing to the promotion of tumor growth and progression. The tumor endothelium can act as a selective barrier that regulates the entry, stability, and activation status of immune cells, but the mechanistic underpinnings of this barrier activity remain poorly understood. The EphB4 receptor tyrosine kinase and its ligand ephrinB2 define novel molecular targets. Upon cell to cell contact, both EphB4 and ephrinB2 can signal via their cytoplasmic domains. Though they have been extensively studied in cell migration and angiogenesis in early embryonic development, little has been published on their role in modulating the cancer immune microenvironment. Our data show that ephrinB2 is expressed on the tumor vasculature and is upregulated by RT and that EphB4 is expressed on immunosuppressive regulatory T cells (Tregs). Inhibiting EphB4-ephrinB2 interaction with a peptide (TNYL-RAW) results in the selective, and exclusive, reduction in infiltration of Tregs while increasing activation of CD8+ and CD4+Foxp3- T cell populations. Tregs, we have demonstrated, play a key role in the development of resistance to RT, and their depletion re-establishes responsiveness to therapy in HNSCC murine models. We hypothesize that RT’s upregulation of ephrinB2 on tumor endothelial cells acts preferentially on EphB4 expressing Tregs, and blocking this interaction reduces their intratumoral infiltration and survival, which allows CD8+ and CD4+ effector cells to induce tumor regression. In Aim 1, we will analyze the mechanistic outcomes of Treg EphB4 and endothelial ephrinB2 interaction on Treg transendothelial trafficking, intratumoral homing, and survival using genetically engineered animal models with ephrinB2 deleted on endothelial cells or EphB4 deletion on Tregs after RT. In Aim 2, we will interrogate the cellular and molecular mechanisms triggered by the interaction between endothelial ephrinB2 and EphB4- expressing Tregs in endothelial-Treg co-culture assays after RT. Targeted inhibition of STAT3, AKT, Erk pathways will be done with pharmacological inhibitors based on our preliminary data. We expect that these studies will elucidate the molecular and cellular parameters of EphB4-ephrinB2 inhibitors and will provide the necessary information to develop a more effective therapy for RT resistant HNSCC.

抽象的对高风险头部和颈部鳞状细胞的抗性辐射疗法（RT）仍然是一个挑战问题癌（HNSCC）患者。抗PD1现在在一线和二线设置中获得批准，表明这些肿瘤中的大多数对治疗有抵抗力。该领域正在等待多个试验测试的结果结合免疫疗法和RT可以帮助避免对RT的抵抗，但是许多临床前研究（包括从我们的实验室中）表示，治疗耐药性仍在此类组合中发展目的地。首选 RT在肿瘤微环境（TME）中募集独特的免疫抑制细胞亚型对RT的反应在促进肿瘤生长和进展方面起着重要作用。这肿瘤内皮可以充当调节进入，稳定性和激活状态的选择性障碍免疫细胞，但这种屏障活性的机械基础知识仍然很少。 EPHB4 受体酪氨酸激酶及其配体ephrinb2定义了新的分子靶标。在与细胞接触的细胞接触时，两者都 Ephb4和Ephrinb2可以通过其细胞质结构域发出信号。尽管他们已经广泛研究了细胞迁移和血管生成在早期胚胎发育中，几乎没有关于其在调节癌症免疫微环境。我们的数据表明，ephrinb2在肿瘤上表达脉管系统，由RT进行更新，EPHB4在免疫抑制性T细胞上表示（Tregs）。抑制EPHB4-磷与肽（TNYL-RAW）的相互作用会导致选择性和独家，减少Treg的浸润，同时增加CD8+和CD4+ FOXP3-T细胞种群的激活。 Tregs，我们已经证明，在对RT的抵抗力发展中发挥关键作用，并且它们的枯竭重新建立 HNSCC鼠模型中对治疗的反应。我们假设RT在肿瘤内皮细胞优先作用于表达Treg的EPHB4，并阻止这种相互作用减少它们肿瘤内浸润和存活率，它允许CD8+和CD4+效应细胞诱导肿瘤消退。在 AIM 1，我们将分析Treg上Treg Ephb4和内皮Ephrinb2相互作用的机械结果使用基因工程的动物模型，带有基因工程的动物模型 Ephrinb2在RT后在Tregs上的内皮细胞或EPHB4缺失上删除。在AIM 2中，我们将审问由内皮ephrinb2和ephb4-之间的相互作用触发的细胞和分子机制在RT之后，在内皮Treg共培养测定中表达Tregs。靶向抑制STAT3，AKT，ERK 根据我们的初步数据，将使用药物抑制剂来完成途径。我们希望这些研究将阐明EPHB4-二氧化体抑制剂的分子和细胞参数，并将提供为RT抗性HNSCC开发更有效疗法的必要信息。