Radiation-induced targeted extracellular vesicles -based gene delivery for glioma therapy

放射诱导的基于细胞外囊泡的基因递送用于神经胶质瘤治疗

• 批准号: 9902892
• 负责人: BAKHOS A TANNOUS
• 金额: $ 24.86万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2021-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9902892
• 关键词: Adaptive Immune System; Affinity; Animals; Antibodies; Brain; Brain Neoplasms; CD47 gene; CD8-Positive T-Lymphocytes; Cells; Characteristics; Chemotherapy and/or radiation; Development; Eating; Excision; Exhibits; FDA approved; Gene Delivery; Glioblastoma; Glioma; Immune; Immune checkpoint inhibitor; Immune response; Immunosuppression; Immunotherapy; Injections; Innate Immune System; Integrin alphaVbeta3; Intravenous; Ligands; Malignant neoplasm of brain; Modification; Mus; Operative Surgical Procedures; Patients; Peptides; Property; RGD (sequence); Radiation; Radiation Dose Unit; Radiation therapy; Signal Transduction; Site; Small Interfering RNA; Surface; Survival Rate; System; Therapeutic; Tumor Antigens; Tumor-associated macrophages; Vascular Endothelial Cell; Vesicle; adaptive immune response; base; cancer type; checkpoint inhibition; clinical application; cytotoxic CD8 T cells; extracellular vesicles; immune checkpoint; immunogenicity; improved; intravenous administration; mouse model; nanotherapeutic; nerve stem cell; outcome forecast; programmed cell death ligand 1; radiation effect; recruit; targeted delivery; therapeutic transgene; tumor; tumor growth; tumor microenvironment; tumor-immune system interactions; uptake

Abstract Glioblastoma (GBM) is the most common primary malignant brain tumor with poor prognosis. Therapeutic suppression of immune checkpoint molecules elicits a tumor immune response and improves long-term survival in several types of cancers. GBM cells highly express immune checkpoint molecules including programmed death-ligand 1 (PD-L1) a critical “don’t find me” signal to the adaptive immune system, and CD47, a “don’t eat me” signal to the innate immune system as well as a regulator of the adaptive immune response. Although radiation therapy has been shown to counteracts the immunosuppressive GBM microenvironment by enhancing the presentation of normally suppressed tumor-associated antigens, promoting CD8+ T cell recruitment, radiation enhances even further the expression of PD-L1 on tumor and microenvironment. Unfortunately, little effect has been observed with checkpoint inhibitors against GBM. An effective GBM therapy requires a delivery system that reaches the tumor in the brain, with limited systemic effect. Endogenous small vesicles known as extracellular vesicles (EVs) hold a great promise as a delivery vehicle given their unique properties including low immunogenicity and innate stability. However, intravenous delivery of EVs to the brain remains a major challenge due to poor targeting of unmodified EVs, which can be improved by surface modification. Our preliminary results shows that The cyclo(Arg-Gly-Asp- D-Tyr-Lys) peptide, which exhibits high affinity to integrin αvβ3 on tumor vascular endothelial cells, could be conjugated on EVs surface (derived from FDA-approved normal neural progenitor cells), resulting in improved EV accumulation in brain tumors after intravenous administration. Furthermore, building on recent studies showing that short bursts of radiation therapy can prime tumors for enhanced accumulation and intratumoral distribution of nanotherapeutics in tumor-associated macrophages-dependent fashion, we showed that glioblastomas primed with radiation had an enhanced uptake of targeted EVs. In this proposal, we will take advantage of these unique characteristics of targeted EVs and load them with small interfering RNAs (siRNAs) against PD-L1 and CD47 to achieve enhanced immune response at the glioblastoma site, primed with radiation. We will evaluate whether radiation therapy will prime glioblastomas for enhanced uptake of these targeted EV across the BBB to deliver siRNAs to GBM, to increase CD8 T cells cytotoxic activity, thus halting tumor growth and prolonging animal survival in a syngeneic graft GBM mouse model.

抽象的 胶质母细胞瘤（GBM）是最常见的原发性恶性脑肿瘤，预后不良。治疗性 免疫切除点分子的抑制会引起肿瘤免疫响应并改善长期 在几种类型的癌症中生存。 GBM细胞高表达免疫检查点分子，包括 编程的死亡配体1（PD-L1）对适应性免疫系统的关键“别找到我”，并且 CD47，对先天免疫系统的“不要吃我”信号以及适应性免疫的调节器 反应。尽管已证明放射治疗可以抵消免疫抑制GBM 微环境通过增强正常抑制肿瘤相关的抗原的表现， 促进CD8+ T细胞募集，辐射进一步增强了PD-L1在肿瘤上的表达和 微环境。不幸的是，检查点抑制剂针对GBM几乎没有效果。一个 有效的GBM治疗需要一个到达大脑肿瘤的递送系统，全身有限 影响。内源性的小蔬菜被称为细胞外蔬菜（EV）有一个巨大的诺言作为交付 车辆具有独特的特性，包括低免疫原性和先天稳定性。然而， 由于未修饰的电动汽车的靶向不力，静脉注射电动汽车向大脑递送仍然是一个重大挑战。 可以通过表面修饰来改进。我们的初步结果表明Cyclo（arg-gly-asp-- d-tyr-lys）胡椒，在肿瘤血管内皮细胞上表现出对整合素αVβ3的高亲和力，可能是 在电动汽车表面（源自FDA批准的正常神经祖细胞）上结合，导致 静脉内给药后，脑肿瘤中的EV积累改善。此外，建立在最近的基础上 研究表明，放射治疗的短爆发可以使肿瘤促进积累和 纳米疗法在肿瘤相关巨噬细胞中的肿瘤内分布依赖性时尚，我们 表明用辐射启动的胶质母细胞瘤具有增强的目标电动汽车的吸收。在此提案中， 我们将利用目标电动汽车的这些独特特征，并用小的干扰加载它们 针对PD-L1和CD47的RNA（siRNA）在胶质母细胞瘤部位获得增强的免疫增强响应， 带有辐射的素数。我们将评估放射疗法是否会为增强的胶质母细胞瘤奠定基础 在BBB上吸收这些靶向EV，以将siRNA传递到GBM，以增加CD8 T细胞细胞毒性 活性，从而在同基因移植GBM小鼠模型中停止肿瘤生长并延长动物生存。