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

• 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
• 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

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)。细胞敏感性 电离辐射（IR）受细胞内和细胞外因素控制。帮助战胜肿瘤 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 放射增敏剂应能增加肿瘤杀灭率并改善患者预后。在实践中，临床实用性 此类药物因限制剂量的副作用而受到限制。为了解决这些问题，我们正在开发可激活的 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。 ACPP 由药物缀合的聚阳离子细胞穿透剂组成 肽和自抑制聚阴离子肽通过柔性肽接头彼此分开。我们的 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，阻断细胞内药物的摄取。当在肿瘤内遇到 MMP 2/9 时，ACPP 被裂解（即“激活”）并释放药物结合的细胞穿透肽，然后被吸收 由肿瘤细胞。我们的 ACPP 探头的一个优点是它们可以设计为非侵入式成像 通过合成比率 ACPP 来检测细胞外肿瘤蛋白酶的活性。比例 ACPP 标记为 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原位测量不同的肿瘤蛋白酶活性。一个 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 的兴趣。我们提案的目标是开发 ACPP 探针来选择性地对肿瘤进行放射增敏。瞄准 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。为了实现这一目标，药物和荧光团将与 ACPP 结合并与 IR 结合。在 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 蛋白酶。识别 IR 诱导的 ACPP 裂解将促进 IR 引导药物递送的开发。在 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 类别放射增敏药物与具有不同蛋白酶连接体的 ACPP 缀合。一起，我们的学习 将测试如何利用 ACPP 来提高放射治疗的治疗率。