声控CPPs介导叶酸靶向载10-HCPT相变纳米粒研制及超声分子成像、治疗与监控研究

To solve the key problem of ultrasound molecular imaging and therapy for tumor- lack of "comprehensive"tumor cell targeting ultrasound molecular probe, we plan to construct cell penetrating peptides (CPPs )-mediated folic acid targeting phase-shift perfluorocarbon nanoparticles containing 10-HCPT based on previous research. The nanoparticles will be mediated targeted "each tumor cell inside and outside" by CPPs because of its penetrating barriers of cell membranes and extracellular matrix. The nanoparticles will be changed into microbubbles using phase-shift technology, and ultrasound molecular imaging and quantitative image analysis for target lesion will be taken using "low- power ultrasound molecular imaging and therapy systems" and DFY diagnostic ultrasound for quantitative image analysis developed by our laboratory, which will lay the foundation of prominent improvement of ultrasound molecular imaging and therapy for tumor. Meanwhile, we will verify synergistic anti-tumor effects of 10-HCPT and "explosion effect" of microbubbles ruptured within the cell, which will increase target anti-tumor therapy level. CPPs-mediated targeting folic acid phase-shift perfluorocarbon nanoparticles containing 10-HCPT can realize high-quality ultrasound molecular imaging and safe and efficient drug delivery, which will provide a new idea and new methods for the development of ultrasound molecular imaging，therapy and monitor of tumor.

针对肿瘤超声分子成像与靶向治疗的核心问题-缺乏"全面"靶向肿瘤细胞超声分子探针，课题组结合前期研究基础，设想构建细胞穿膜肽（Cell Penetrating Peptides, CPPs）介导靶向载十羟基喜树碱（10-HCPT）相变纳米粒，利用CPPs可以穿过细胞膜及细胞外基质屏障优点，实现介导纳米粒靶向"每一个肿瘤细胞里里外外"，并通过相变技术使纳米粒相变成含气微泡，联合实验室开发的"低功率超声分子显像与治疗系统"和 DFY型超声图像定量分析诊断仪，进行靶病变超声分子成像及定量分析，为超声分子成像质量实现质的提高奠定基础，同时验证设想10-HCPT与细胞内微泡破裂产生的"爆炸效应"有协同增效作用，进而提高靶向抗肿瘤治疗水平。预期成功制备的 CPPs介导靶向载10-HCPT相变纳米粒，实现高质量超声分子成像及安全高效药物投递，有望为肿瘤超声分子成像、治疗与监控提供一种新思路和新方法。

肿瘤是严重威胁人类健康的重要疾病，化疗是治疗肿瘤的一个重要策略。然而，较差的肿瘤靶向和化疗药物的全身分布影响化疗的临床疗效。为了实现精确的肿瘤靶向、增加肿瘤靶点积聚及提高肿瘤治疗水平，肿瘤靶向药物递送系统成为目前研究热点。超声分子影像学是分子影像学的重要分支，尤其是与超声靶向破坏微泡技术（UTMD ）联合可实现药物/基因定位递送的独特优势，使其成为一种极具临床应用潜力的新型诊疗一体化技术。该项目成功合成具有细胞穿膜特性的穿膜肽；成功制备了一种穿膜肽修饰的靶向载药相变脂质纳米粒（HA/CPPs-10-HCPT-NPs）作为新型的超声分子探针和药物递送载体；优化体内外相变条件，实现对其相变过程及药物释放的安全可控，为其应用于超声分子成像与治疗奠定基础；实现HA/CPPs-10-HCPT-NPs对肿瘤细胞模型的体外寻靶能力、细胞穿膜性及可控药物释放的靶向治疗；实现HA/CPPs-10-HCPT-NPs对肿瘤动物模型的体内超声分子成像及靶向治疗。该项目研制的穿膜肽修饰的靶向载药相变脂质纳米粒，同时具有穿透双层肿瘤组织屏障、细胞外积聚和细胞内渗透作用，在粒径优势下，纳米粒能够穿过肿瘤血管内皮细胞间隙；在透明质酸及穿膜肽的介导下，纳米粒能够靶向肿瘤细胞，并可穿入到深层肿瘤组织细胞，实现细胞水平精准定位；联合LIFU聚焦辐照后，纳米粒所包裹的液态PFP相变成气体，纳米粒从而变成微泡增强超声成像效果，实现超声分子成像； 联合UTMD导致的“爆炸效应”、定点释放药物，实现物理化学协同治疗肿瘤作用。该纳米粒可用于肿瘤的诊疗一体化，为实现真正分子水平的肿瘤精准诊疗提供一种新策略和新方法。该项目申请国家发明专利1项，发表SCI 2篇（单篇最高12.712）及CSCD 6篇。