负载PAK1抑制剂的双靶向壳聚糖纳米药物靶向治疗肝癌的作用机制

Hepatocellular carcinoma (HCC) is malignancy tumor with high morbidity and mortality in China and chemotherapy is one of most important treatment for HCC. However, current efficacy of chemotherapy and targeting to tumor cells are not satisfied. In previous study, we successfully synthesized novel dual targeting ligand-modified nanoparticles as drug carrier and discovered that PAK1 perhaps an ideal target for treatment of liver cancer. Therefore, we hypothesize that selective inhibition of PAK1 activity, mediated by dual targeting ligand-modified nanoparticles, perhaps is an efficacious targeting drug for HCC. In this research, we will attempt to fabricate the dual targeting nanoparticles loaded with IPA-3 or recombinant plasmid PAK1-shRNA and treat hepatoma cells with the nanoparticles, and then detect the targeting efficacy to hepatoma cells and explore the effect and molecule mechanism of hepatoma cells via inhibition of PAK1 by the nanoparticles in vitro. Simultaneity, mouse liver cancer model will be prepared and treated with the nanoparticles via intravenous injection, then distribution in each tissue and pharmacokinetics will be measured, and the inhibition effect and mechanism of liver cancer growth and angiogenesis through targeted intervention PAK1 will be investigated in vivo. This research will investigate the targeting efficacy of novel dual targeting ligand-modified nanoparticles for hepatoma cells and explore the inhibition of liver cancer growth and mechanism through targeted intervention PAK1, to seek for a novel effective targeting drug for HCC.

肝细胞癌在我国是一种发病率和死亡率都很高的恶性肿瘤，化疗是肝癌治疗的重要手段之一。但是，目前的药物载体及治疗靶点均不理想。在前期研究中，我们成功合成了肝癌双靶向纳米药物载体，并发现PAK1可能是肝癌治疗的一个理想靶点。为此，我们设想：以PAK1为靶点，用双靶向纳米载体为运载工具，抑制PAK1的活性可能是一种有效的肝癌靶向药物治疗方案。 本项目拟制备负载IPA-3和PAK1-shRNA的双靶向纳米颗粒，干预体外培养的肝癌细胞，检测该纳米药物的肝癌细胞靶向性，并探讨抑制PAK1对其生物学行为的影响及分子机制。制备小鼠肝癌模型，静脉给予纳米颗粒，以检测该纳米药物的体内组织分布及药代动力学，并探讨靶向干预PAK1对肝癌生长和血管生成的抑制作用及机制。本项目将研究双靶向纳米药物载体的肝癌细胞靶向性，并深入探讨靶向干预PAK1对肝癌生长和转移的抑制作用及分子机制，以探索一种有效的肝癌靶向药物治疗方案。

药物治疗是肝癌治疗的重要组成部分，但是药物运载途径和靶向富集是疗效欠佳的原因之一。纳米药物是近年来新兴的肿瘤治疗手段，可通过纳米载体将药物或基因选择性运载至肿瘤细胞内，从而提高其在肿瘤细胞内的浓度并降低副反应，以达到良好的治疗效果。本项目前期研究中，我们设计了新型肝癌双靶向壳聚糖纳米药物载体，并证实PAK1是肝癌药物治疗的一个理想分子靶点。在此基础上，进一步制备了负载PAK1-siRNA双靶向壳聚糖纳米载体系统，并处理人肝癌细胞，以检测该纳米药物载体的肝癌细胞靶向性，并探讨该纳米载体系统抑制PAK1对肝癌细胞生物学行为的影响及分子机制。同时，建立小鼠肝癌模型，尾静脉注射纳米颗粒，检测该纳米药物载体的体内组织分布及药代动力学，并探讨靶向干预PAK1对肝癌生长和血管生成的抑制作用及机制。研究结果表明：1. 通过下调肝癌细胞PAK1的表达，可显著抑制肝癌细胞的增殖活性，促进凋亡，从而抑制肝癌的生长；2. 双靶向壳聚糖纳米载体系统对肝癌细胞的靶向性明显优于单靶向和无靶向载体，可选择性富集于肝癌肿瘤病灶中，并且具有良好的生物亲和性；3. 负载PAK1-siRNA双靶向壳聚糖纳米载体系统可靶向作用于肝癌细胞和肝癌瘤体组织，下调PAK1的表达，从而抑制肝癌的发生发展。本项目全面证实了该双靶向纳米药物载体的肝癌细胞靶向性，并探讨靶向干预PAK1对肝癌生长和转移的抑制作用，为肝癌的靶向治疗提供了一种新的策略。