EGFR阳离子多肽脂质基因载体的构建及在肝癌治疗方面的应用

体内高靶向性非病毒基因载体的研发是实现安全有效基因治疗的关键。本课题拟使用具有EGFR靶向功能的短肽GE11衍生物替代磷脂，构建尺寸可控、粒径均一、表面多肽含量可控、具备脂质双层膜结构的阳离子多肽脂质囊泡（CPV）。通过调整CPV的制备工艺、组成或进行纳米粒的功能化组装（PEG长循环、半乳糖的肝靶向功能）等途径来最大限度的提高CPV的体内外基因递送效率、生物安全性和对肝肿瘤的靶向性；并通过研究不同CPV纳米粒与细胞间的相互作用关系和体内运转途径、结合纳米粒的理化性质、空间结构与细胞摄取和靶向递送间的关系探索CPV介导基因转导机制。最终使用功能性CPV单独或同时荷载具有肝癌治疗功能的乙酰胆碱酯酶siRNA及质粒基因进行荷瘤裸鼠的抑瘤实验，并进行一系列的体内外评价。本项目将构建一种高靶向性、高安全性和高基因递送效率的多肽脂质基因载体系统，并将为癌症的基因治疗提供有价值的实验数据。

Development of highly targeted non-virus gene carrier is the key to achieve safe and effective gene therapy. Delivery of gene by nanoparticles (NPs) that selectively target lesion site or malignant cells promises to reduce the side effects of chemical drugs and to enable the using of nano-tools for personalized medicine. To realize this potential, targeted nanocarriers must simultaneously overcome multiple challenges, including specificity, stability and a high capacity for different cargos. Here we report cationic peptide vesicles-supported lipid bilayers (CPVs) that synergistically combine properties of nano-micelle particles and liposomes. CPVs modified with a targeting peptide of epidermal growth factor receptor (EGFR) that binds to human hepatocellular carcinoma exhibit higher drug delivery ability and gene transfection efficiency than for non-targeted NPs. Furthermore, CPVs can be loaded with different cargos of therapeutic (drugs and small interfering RNA) and diagnostic (quantum dots) agents and modified to promote nuclear accumulation of selected cargos. The CPVs vector with EGFR targeting possessed promote AChE gene expression. The siRNA CPVs/AChE complexes produced excellent gene delivery ability in EGFR-positive liver cancer cells in vitro and in vivo.