多重肺肿瘤靶向热敏脂质纳米粒载体的构建及治疗作用研究

Lung cancer is the leading cause of new cancer cases and also is the number one cause of cancer death worldwide. Among the major reasons of treatment failure are the devastating side effects caused by systemically applied chemotherapeutic agents. There has been enormous interest in the exciting area of superparamagnetic iron oxide(SPIO) nanoparticles-based inhalation aerosols for lung cancer therapy. But the most significant problem is that aerosols cannot specifically identify and target malignant cells among healthy cells and will not diffuse to a significant extent into a tumor. The aim of this project is to prepare a new multitargeted nanoparticle pulmonary delivery system which combines the inhalation targeting, magnetic targeting and receptor targeting, and exerts synergetic antitumor activity of hyperthermia and chemotherapy (chemohyperthermia) activated by alternating magnetic field. The major study areas of this project include: (1) preparation and characterization of SPIO loaded lipid nanoparticles functionalized with EGFR targeting ligand and near-infrared fluorescent dye Cy 5.5; (2) in vitro study of lung tumor cell targeting and intracellular chemohyperthermia effects; (3) in vivo study of therapeutic effect against lung cancer by inhalation in a mouse lung tumor model and the toxicity evaluation in healthy nude mice; (4) assessment of the deposition and the target efficiency of nanoparticles in the lung by setting up a new quantitative fluorescence imaging method, which has not been reported by other researchers yet. This project will provide theoretical and experimental basis for inhalation therapy for lung cancer.

肺癌是发病率和死亡率最高的恶性肿瘤，传统化疗方法由于对肺组织缺乏选择性，毒副作用大等原因，疗效不理想。基于氧化铁磁流体（SPIO）的纳米气雾剂是近年治疗肺癌的研究热点，但如何提高药物对肺肿瘤靶向性及渗透性、降低对正常组织毒性仍是待解决的科学问题。目的：构建一种全新的具有雾化靶向、磁靶向以及细胞靶向等多重靶向作用的纳米粒载体用于雾化给药，并利用SPIO在交流磁场下的产热作用与化疗药物一起发挥热化疗协同抗肿瘤效果。研究内容：（1）磁性脂质纳米粒的构建、表征及雾化性能研究；（2）对肺肿瘤细胞靶向性、细胞内热化疗作用研究；（3）雾化吸入纳米粒对原位肺癌裸鼠治疗作用以及对裸鼠肺组织刺激性及毒性研究；（4）建立全新的肺组织定量荧光成像法，对纳米粒在肺组织的空间分布及肺肿瘤靶向效率进行定量研究，目前尚未见类似报道。本项目将为多重靶向纳米粒用于肺癌雾化治疗提供理论及实验依据。

肺癌是发病率和死亡率最高的恶性肿瘤，传统化疗方法由于对肺组织缺乏选择性，毒副作用大等原因，疗效不理想。基于氧化铁磁流体（SPIO）的纳米气雾剂是近年治疗肺癌的研究热点，但如何提高药物对肺肿瘤靶向性及渗透性、降低对正常组织毒性仍是待解决的科学问题。目的：构建一种全新的具有雾化靶向、磁靶向以及细胞靶向等多重靶向作用的纳米粒载体用于雾化给药，并利用SPIO 在交流磁场下的产热作用与化疗药物一起发挥热化疗协同抗肿瘤效果。研究内容：（1）磁性脂质纳米粒的构建、表征及雾化性能研究；（2）对肺肿瘤细胞靶向性、细胞内热化疗作用研究；（3）雾化吸入纳米粒对原位肺癌裸鼠治疗作用以及对裸鼠肺组织刺激性及毒性研究；（4）采用荧光成像法，对纳米粒在肺组织的空间分布及肺肿瘤靶向效率进行定量研究， 结果表明：所制备的多重肺肿瘤靶向热敏脂质纳米粒（Tar-FMLNP）粒径大小合适，载药载铁量高，热敏性能好，稳定性好，适合雾化给药。体外细胞学实验表明细胞毒性与温度、纳米粒浓度和AMF作用时间呈正相关。随着温度的升高，细胞毒性增强。在体分布实验表明，雾化吸入1h后，肺部组织纳米粒浓度达到最大，随后随时间的延长，肺组织内浓度逐渐降低。体内抗肿瘤实验表明，Tar-DOT-FMLNP明显抑制肿瘤的生长，产生磁疗和化疗双重抗肿瘤作用。本文研究结果为多重肺肿瘤靶向热敏脂质纳米粒在肺癌治疗中的应用提供理论和实验依据。