液气转换型阳离子超声纳米囊泡高效负载HOP-siRNA抑制肝癌射频消融术后复发进展的实验研究

Ultrasound-guided radiofrequency ablation (RFA) is an important treatment modality for hepatocellular carcinoma (HCC). But it remains the serious problems of incomplete ablation and high recurrence after RFA, and there is no effective inhibitory method for these problems until now. Our preliminary results showed that heat stimulus could induce the increased expression of stress induced phosphoprotein-1(HOP) of HCC cells, and then promoted the proliferation and inhibited the apoptosis of HCC cells and induced the epithelial mesenchymal transition (EMT). These evidences suggest that HOP plays an important role in the tumor recurrence and progression after incomplete ablation. Nanodroplet is an effective gene delivery vector. Our research group has preliminarily established the ultrasound-triggered phase-transition cationic nanodroplet with high efficiency of gene delivery. In this research, we are going to bear HOP-siRNA within the droplet and to modify droplet surface with folic acid. Based on these, we hypothesized that under ultrasound mediation，nanodroplet bearing HOP-siRNA could efficiently deliver HOP-siRNA to residual HCC cells after incomplete RFA, which in turn inhibited tumor proliferation, EMT and promoted apoptosis. Our research is going to synthesize a HCC-targeted phase-transition cationic nanodroplet with HOP-siRNA delivery function, and to investigate its anti-tumor effect. Also, we combined it with RFA to explore its effect and mechanism on controlling tumor recurrence after RFA from cells and animal models, with the methods of PCR, western blotting, immunofluorescence and others. This study will provide a novel thicking in the inhibition of HCC recurrence after RFA.

超声引导下射频消融（RFA）是治疗肝癌的重要手段，但存在术后高残留高复发问题，目前尚无有效抑制手段。我们前期发现热刺激可致肝癌细胞应激诱导磷酸化蛋白1(HOP)表达增加，进而促进肝癌细胞增殖、抑制凋亡并介导EMT，提示HOP在肿瘤不全消融术后复发进展发挥作用。纳米囊泡是有效基因治疗载体，我们前期已制备出高效负载基因的液气转换型阳离子纳米囊泡，本研究将结合HOP-siRNA并对囊泡表面行叶酸修饰，形成肝癌靶向传输HOP-siRNA的一体化纳米囊泡。我们假设载HOP-siRNA纳米囊泡在超声介导下可高效传输靶基因到RFA术后残余肝癌细胞内，抑制肿瘤细胞增殖及EMT并诱导其凋亡。本研究拟构建上述纳米囊泡，检测其抑癌作用，并将其与RFA联用，从细胞及动物模型阐明载HOP-siRNA靶向纳米囊泡可有效控制肝癌RFA术后复发进展的作用及机制，为抑制肝癌RFA术后复发提供新思路。

超声引导下射频消融（RFA）是治疗肝癌的重要手段，但术后高残留高复发问题限制其进一步提高临床疗效，寻求有效抑制复发转移手段是本领域的重点难点问题。本研究按照计划顺利完成，针对“载HOP-siRNA纳米囊泡在超声介导下可高效传输靶基因到RFA术后残余肝癌细胞内抑制肿瘤细胞生长”的问题，项目构建了肝癌靶向传输HOP-siRNA的一体化超声纳米囊泡，对纳米囊泡进行了基本的特性表征、转染效能评估及细胞毒性评估等，在细胞实验及裸鼠原位肝癌模型上发现其具有抑制肝癌细胞生长迁移的能力，并进一步在裸鼠原位肝癌不全消融模型上将纳米囊泡与RFA联用，发现纳米囊泡联合RFA可有效抑制消融后残余肝癌细胞生长，从细胞及动物模型阐明载HOP-siRNA靶向纳米囊泡可有效控制肝癌RFA术后复发进展的作用，为抑制肝癌RFA术后复发提供新思路。