Developing targeted activatable peptides to amplify radiosensitizer delivery

开发靶向可激活肽以增强放射增敏剂的输送

基本信息

批准号：
9379141
负责人：
Sunil J Advani
金额：
$ 7.75万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-15 至 2019-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9379141
关键词：
Address Advanced Malignant Neoplasm Adverse effects Architecture Area Biodistribution Biosensing Techniques Cancer Patient Cells Charge Cleaved cell Clinical Cytotoxic Chemotherapy DNA Repair Data Dependency Development Diagnosis Diagnostic Disease Dose Drug Delivery Systems Drug Kinetics Drug Monitoring Drug Sensitization Drug Targeting Environment Extracellular Matrix Fluorescence Resonance Energy Transfer Functional Imaging Gelatinase A Generations Goals Head and Neck Cancer Head and neck structure In Situ Ionizing radiation Irradiated tumor Kinetics Label Link MMP14 gene Malignant Neoplasms Matrix Metalloproteinase Inhibitor Matrix Metalloproteinases Measures Modeling Molecular Monitor Morbidity - disease rate Mus Neoplasm Metastasis Normal tissue morphology Organ Preservation Patient-Focused Outcomes Patients Peptide Hydrolases Peptides Pharmaceutical Preparations Pharmacology Play Prodrugs Property Quality of life Radiation exposure Radiation therapy Radiation-Sensitizing Agents Radioresistance Radiosensitization Resistance Role Technology Testing Therapeutic Tissues Toxic effect Unresectable Work base chemotherapy cyanine dye 5 design effective therapy extracellular flexibility fluorophore improved improved outcome inhibitor/antagonist innovation interest killings neoplastic cell non-invasive imaging overexpression peptide drug polypeptide pre-clinical ratiometric response theories tool tumor tumor growth tumor microenvironment tumor progression uptake

项目摘要

Project Summary/Abstract Tumor resistance to radiotherapy continues to be a significant problem in improving outcomes of patients diagnosed with locally advanced, unresectable cancers including head and neck (HNC). Cellular sensitivity to ionizing radiation (IR) is governed by intracellular and extracellular factors. To help overcome tumor radioresistance, drugs that sensitize tumor to ionizing radiation (IR) are used. In theory, more potent radiosensitizers should increase tumor kill and improve patient outcomes. In practice, the clinical utility of of such drugs is curtailed by side effects that limit doses. To address these issues, we are developing activatable cell penetrating peptide (ACPP) probes to monitor and selectively deliver conjugated radiosensitizers to tumors based on extracellular tumor protease activity. ACPP consist of a drug conjugated polycationic cell penetrating peptide and an autoinhibitory polyanionic peptide separated from each other by a flexible peptide linker. Our initial peptide linker is cleaved by matrix metalloproteinases (MMP) 2/9, abundantly expressed in tumors. Intact, drug conjugated ACPP is “pro-drug” where the the drug linked cell penetrating peptide is neutralized by the polyanionic peptide, blocking intracellular drug uptake. Upon encountering MMP 2/9 within tumors, ACPP is cleaved (i.e. “activated”) and releases the drug conjugated cell-penetrating peptide, which is then taken up by tumor cells. An advantage of our ACPP probes is that they can be designed to non-invasively image extracellular tumor protease activities by synthesizing ratiometric ACPP. Ratiometric ACPP are labeled with Cy5 and Cy7 on the polycationic and polyanionic peptide respectively, acting as a FRET donor/acceptor pair. By using different protease sensitive peptide linker sequences between the two charged polypeptides, ratiometric ACPP Cy5:Cy7 emission ratio non-invasively measures distinct tumor protease activities in situ. A unique property of ACPP is the dependency on protease cleavage begets enzymatic amplification in the area of interest. The goals of our proposal are to develop ACPP probes to selectively radiosensitize tumors. In Aim 1, we will test the pharmacokinetics, biodistribution and efficacy of ACPP conjugated radiosensitizers in murine HNC models. To achieve this, drugs and fluorophores will be conjugated to ACPP and combined with IR. In Aim 2, we will interrogate in situ how IR alters extracellular protease activities in a dose dependent and temporal manner using a panel of ratiometric ACPP with distinct linkers cleaved preferentially by specific proteases. Identifying IR inducible ACPP cleavage will promote IR guided drug delivery development. In summary, ACPP radiosensitizer delivery has several innovative features that warrant pre-clinical inquiry. Diagnostically, ratiometric ACPP allows for non-invasive imaging of intrinsic tumor microenvironment proteases and IR's extrinsic influence. Therapeutically, ACPP's modular architecture allows for permutations of different classes radiosensitizing drugs to be conjugated to ACPPs with distinct protease linkers. Together, our studies will test how ACPPs can be exploited to improve the therapeutic ratio of radiotherapy.

项目概要/摘要肿瘤对放疗的耐药性仍然是改善患者预后的一个重要问题被诊断患有局部晚期、不可切除的癌症，包括头颈癌 (HNC) 的细胞敏感性。电离辐射 (IR) 受细胞内和细胞外因素控制，有助于克服肿瘤。放射抗性，使用使肿瘤对电离辐射（IR）敏感的药物理论上更有效。在实践中，放射增敏剂应该增加肿瘤杀灭率并改善患者的治疗效果。为了解决这些问题，我们正在开发可激活的药物。细胞穿透肽 (ACPP) 探针，用于监测并选择性地将缀合放射增敏剂递送至肿瘤基于细胞外肿瘤蛋白酶活性的 ACPP 由药物缀合的聚阳离子细胞穿透组成。我们的肽和自抑制聚阴离子肽通过灵活的肽连接体彼此分开。初始肽接头被基质金属蛋白酶 (MMP) 2/9 切割，在肿瘤中大量表达。完整的药物偶联 ACPP 是“前药”，其中药物连接的细胞穿透肽被中和聚阴离子肽，在肿瘤内遇到 MMP 2/9 时阻断细胞内药物摄取。被裂解（即“激活”）并释放药物结合的细胞穿透肽，然后被吸收我们的 ACPP 探针的一个优点是它们可以被设计为非侵入性成像。通过合成比率ACPP来标记细胞外肿瘤蛋白酶活性。 Cy5 和 Cy7 分别位于聚阳离子和聚阴离子肽上，充当 FRET 供体/受体对。通过在两个带电多肽之间使用不同的蛋白酶敏感肽接头序列，比例 ACPP Cy5:Cy7 发射比可非侵入性地测量原位不同的肿瘤蛋白酶活性。 ACPP 的独特特性是依赖于蛋白酶切割，从而在该区域产生酶促扩增我们的提案的目标是开发 ACPP 探针来选择性地对肿瘤进行放射增敏。 1、我们将测试ACPP缀合放射增敏剂在小鼠体内的药代动力学、生物分布和疗效 HNC 模型将药物和荧光团与 ACPP 结合并与 IR 结合。目标 2，我们将原位探究 IR 如何以剂量依赖性和使用一组比例 ACPP 的时间方式，其中不同的接头优先被特定的裂解识别 IR 诱导的 ACPP 裂解将促进 IR 引导的药物递送开发。总之，ACPP 放射增敏剂具有多项创新功能，值得临床前研究。在诊断方面，比例 ACPP 允许对内在肿瘤微环境蛋白酶进行非侵入性成像以及 IR 的外在影响在治疗上，ACPP 的模块化架构允许不同的排列。我们的研究将放射增敏药物与具有不同蛋白酶连接体的 ACPP 结合。将测试如何利用 ACPP 来提高放射治疗的治疗率。