Increasing sensitivity and discrimination of breast cancer diagnosis using molecularly targeted, extravascular ultrasound imaging with ultrasound-activated, phase-change nanodroplet contrast agent

使用超声激活相变纳米液滴造影剂进行分子靶向血管外超声成像，提高乳腺癌诊断的灵敏度和辨别力

• 批准号: 9768466
• 负责人: JAMES K TSURUTA
• 金额: $ 7.63万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9768466
• 关键词: Acoustics; Back; Benign; Biodistribution; Biological Assay; Biotin; Blood; Blood Circulation; Blood Vessels; Body Temperature; Caliber; Carrying Capacities; Contrast Media; Custom; DNA; DNA Binding; DNA Probes; Detection; Development; Diagnosis; Diagnostic; Diagnostic Sensitivity; Discrimination; Dose; Encapsulated; Endothelial Cells; Extravasation; FDA approved; Fluorocarbons; Formulation; Future; Gases; Half-Life; Image; Immunohistochemistry; Kidney; Knowledge; Label; Lipids; Liquid substance; Malignant - descriptor; Measures; Methods; Microbubbles; Molecular; Molecular Target; Normal tissue morphology; Organ; Permeability; Phase; Physiologic pulse; Polymerase Chain Reaction; Proteins; Public Health; Reagent; Signal Transduction; Specificity; Stains; Techniques; Temperature; Testing; Time; Tissues; Tumor Tissue; Tumor Volume; Ultrasonography; Vascular Endothelium; breast cancer diagnosis; breast lesion; cancer biomarkers; cancer diagnosis; cancer therapy; contrast enhanced; density; imaging agent; in vivo; interstitial; malignant breast neoplasm; molecular imaging; nano; nanoDroplet; nanoparticle; nanoscale; novel; phase change; pressure; prevent; targeted agent; tumor

ABSTRACT Lipid shelled perfluorocarbon (PFC) microbubbles ranging from 0.5 to 8 microns in diameter have been approved by the FDA to enhance the contrast of blood for diagnostic ultrasound imaging. The micro scale of ultrasound contrast agents limits them to the bloodstream, eliminating the enhanced permeability and retention (EPR) observed in many tumors. The ability to create nanoparticles from existing lipid-shelled microbubble contrast agents lets us leverage the non-toxic formulations of these agents, and lets us create novel targeted nanoparticles using any of the established strategies for formulating targeted microbubbles. Microbubbles targeted to Secreted Frizzled Related Protein 2 (SFRP2) showed significant discrimination between tumor and normal vasculature, and SFRP2 is highly expressed in a variety of breast cancers. We and our colleagues found that cold and increased pressure caused conventional gas-phase ultrasound contrast to condense into lipid-shelled nanodroplets of liquid PFC. With sufficient energy, these non-echogenic agents revert back to conventional ultrasound contrast agents. Nanodroplets share the advantages inherent to nanoparticle strategies for cancer therapy: passive accumulation in tumors enhanced by the EPR effect, targeted accumulation within tumors aided by targeting moieties, and reduced systemic dosing. Activating nanodroplets with ultrasound provides a high degree of spatial selectivity, preventing re-entry of the micro scale bubbles into the vasculature, thus maintaining a high local concentration of contrast agent. Molecular imaging that interrogates the interstitial space within tumors widens the physical scope of imaging with the payoff of a higher density of bound contrast throughout the tumor volume, and additional opportunities to target tumor molecules that are not found in the vascular endothelium. We propose that extravascular molecular imaging with SFRP2- targeted nanodroplets will increase the sensitivity of detecting breast cancer compared to microbubble molecular imaging while maintaining the molecular specificity needed to decrease false diagnoses. A critical barrier to leveraging molecularly targeted, lipid shelled perfluorocarbon nanodroplets is a fundamental lack of knowledge about their biodistribution in normal and tumor tissue. We propose to combine existing, established techniques to create SFRP2-targeted, and non-targeted nanodroplet formulations carrying a biotin and DNA label, determine their circulating half-lives, and use immunohistochemical detection of biotin or quantitative polymerase chain reaction assays of our unique DNA payload to characterize the biodistribution of these liquid perfluorocarbon droplets in normal and tumor tissues. Establishing the ability of targeted nanodroplets to cross the endothelial cell layer leverages existing microbubble contrast agents, promotes development of novel nano agents, and increases the impact of ultrasound for detecting breast cancer by developing a novel, highly sensitive ultrasound method that leverages the discriminatory power of targeted molecular imaging in the vascular and extravascular space of breast lesions.

抽象的 直径为0.5至8微米的脂质壳全氟碳（PFC）微泡已经 经FDA批准以增强血液的对比度进行诊断超声成像。微观 超声对比剂将它们限制在血液中，消除了增强的渗透性和保留率 （EPR）在许多肿瘤中观察到。从现有的脂质壳微泡中创建纳米颗粒的能力 对比剂使我们能够利用这些药物的无毒表述，并使我们创建新颖的目标 纳米颗粒使用任何既定策略来制定目标微泡。微泡 针对分泌的毛躁相关蛋白2（SFRP2）的针对分泌的毛躁，在肿瘤和 正常的脉管系统和SFRP2在多种乳腺癌中高度表达。我们和我们的同事 发现冷压和增加的压力导致常规气相超声与凝结形成鲜明对比 液体pfc的脂质壳纳米三个。使用足够的能量，这些非技术剂还原回 常规的超声对比剂。纳米光共享纳米颗粒固有的优点 癌症治疗策略：EPR效应增强的肿瘤中的被动积累，针对性 通过靶向部分的肿瘤内积累，并减少了全身剂量。激活纳米光 使用超声提供高度的空间选择性，以防止微型秤的重新进入 脉管系统，因此保持较高的局部造影剂浓度。分子成像 询问肿瘤内的间质空间可以扩大成像的物理范围，而收益较高 在整个肿瘤体积中结合对比的密度，以及靶向肿瘤分子的额外机会 在血管内皮中找不到的。我们建议用SFRP2-进行血管外分子成像 与微泡相比 分子成像，同时保持降低错误诊断所需的分子特异性。批判 利用分子靶向，脂质壳的障碍障碍，是基本缺乏 关于它们在正常和肿瘤组织中生物分布的知识。我们建议结合现有的，建立的 创建具有生物素和DNA的非靶向纳米核配方的技术来创建SFRP2靶向和非目标 标签，确定其循环的半衰期，并使用生物素或定量的免疫组织化学检测 聚合酶链反应测定我们独特的DNA有效载荷，以表征这些液体的生物分布 正常组织和肿瘤组织中的全氟化合物。建立靶向纳米光跨的能力 内皮细胞层利用现有的微泡对比剂，促进新型纳米的发展 代理，并通过开发一种新颖的，高度 敏感的超声方法，利用目标分子成像的歧视力 乳房病变的血管和血管外空间。

项目成果

Accelerated blood clearance of targeted ultrasound contrast reduced molecular imaging signal intensity: Secreted Frizzled Related Protein-2 signal remained significantly higher than signal from either Vascular Endothelial Growth Factor Receptor-2 or alpha

目标超声造影剂的加速血液清除降低了分子成像信号强度：分泌的卷曲相关蛋白 2 信号仍然显着高于血管内皮生长因子受体 2 或 α 的信号

• DOI: 10.1109/ultsym.2019.8925919
• 发表时间: 2019
• 期刊: IEEE International Ultrasonics Symposium : [proceedings]. IEEE International Ultrasonics Symposium
• 作者: Tsuruta,James;White,Rachel;Klauber-DeMore,Nancy;Dayton,PaulA
• 通讯作者: Dayton,PaulA