文献：Combined Delivery of Temozolomide and siPLK1 Using Targeted Nanoparticles to Enhance Temozolomide Sensitivity in Glioma

文献链接：

作者：Hui Shi，Shuo Sun,Haoyue Xu,Zongren Zhao，Zhengzhong Han，Jun Jia，Dongmei Wu，Jun Lu，Hongmei Liu，Rutong Yu

相关产品：PCL5000-PEI2000（聚己内酯5000-聚乙烯亚胺2000）

原文摘要：

Introduction: Temozolomide (TMZ) is the first-line chemotherapeutic option to treat glioma; however, its efficacy and clinical application are limited by its drug resistance properties. Polo-like kinase 1 (PLK1)-targeted therapy causes G2/M arrest and increases the sensitivity of glioma to TMZ. Therefore, to limit TMZ resistance in glioma, an angiopep-2 (A2)-modified polymeric micelle (A2PEC) embedded with TMZ and a small interfering RNA (siRNA) targeting PLK1 (siPLK1) was developed (TMZ-A2PEC/siPLK).Materials and Methods: TMZ was encapsulated by A2-PEG-PEI-PCL (A2PEC) through the hydrophobic interaction, and siPLK1 was complexed with the TMZ-A2PEC through electrostatic interaction. Then, an angiopep-2 (A2) modified polymeric micelle (A2PEC) embedding TMZ and siRNA targeting polo-like kinase 1 (siPLK1) was developed (TMZA2PEC/siPLK).Results: In vitro experiments indicated that TMZ-A2PEC/siPLK effectively enhanced the cellular uptake of TMZ and siPLK1 and resulted in significant cell apoptosis and cytotoxicity of glioma cells. In vivo experiments showed that glioma growth was inhibited, and the survival time of the animals was prolonged remarkably after TMZ-A2PEC/siPLK1 was injected via their tail vein.Discussion: The results demonstrate that the combination of TMZ and siPLK1 in A2PEC could enhance the efficacy of TMZ in treating glioma.  

PCL5000 - PEI2000 是一种嵌段共聚物，由分子量为 5000 的聚己内酯（PCL）和分子量为 2000 的聚乙烯亚胺（PEI）组成。聚己内酯（PCL）链段主要由酯键（-COO -）连接的重复单元构成。这种聚酯结构使 PCL 具有良好的生物可降解性，在体内能在酶的催化或者合适的化学环境下逐渐分解为小分子。PCL 还具有不错的机械性能和化合物透过性，它的物理性质有助于在材料形成过程中提供结构支撑。聚乙烯亚胺（PEI）链段含有大量氨基（-NH2），这使得 PEI 具有强碱性。在生理 pH 条件下，氨基容易质子化而带正电荷。这种正电荷特性使 PEI 能够与带负电荷的物质（如核酸）通过静电相互作用结合，在基因转染等应用中有重要作用。基于PCL5000 - PEI2000的性能，该文献合成TMZ-A2PEC/siPLK的路线如下：

图：合成示意

纳米颗粒制备：

  OPSS-PEG-SVA和A2溶解于二甲亚砜中。将反应混合物在室温下轻轻搅拌，过滤，用去离子水透析，冻干得到A2修饰的OPSS-PEG-SVA（A2-OPSS-PEG-SVA）。将A2-OPSS-PEG-SVA和PCL5000-PEI2000完全溶解在丙酮中，并在室温下剧烈涡旋。将混合物滴入纯水中，用磁力搅拌器搅拌，通过膜透析对水纯化。该过程形成了A2-PEG-PEI-PCL，缩写为A2PEC。TMZ-A2PEC采用A2-OPSS-PEG-SVA、PCL5000-PEI2000、TMZ制备TMZ-A2PEC。

将预定量的siPLK-1 A或阴性对照siRNA（NCsiRNA）与一定量的TMZ-A2PEC胶束溶液混合。将混合物涡旋，然后在室温下放置。通过这种方法，根据不同的氮/磷酸盐（N/P）比例形成一系列siRNA和TMZ加载的纳米复合物（TMZ-A2PEC/siPLK1和TMZ-A2PEC/NCsiRNA）。采用同样的方法制备了不含TMZ（A2PEC/siPLK1）或含有FAM标记的siRNA（A2PEC/FAM-siRNA）的纳米复合物。

图：电镜图像

结论：

该文献成功制备了基于PCL5000 - PEI2000合成的TMZ-A2PEC/siPLK。实验表明，TMZ-A2PEC/siPLK能增强细胞对TMZ和siPLK1的摄取，导致胶质tumour细胞Apoptosis 和细胞poison，注射TMZ-A2PEC/siPLK1后，神经胶质tumour的生长受到抑制，动物的存活时间延长。