Abstract Background and objective: The combination of two or more different mechanisms of drugs in the treatment of cancer has become one of the effective methods. The purpose of this study was to successfully prepare a non-viral delivery system that could efficiently co-delivery siRNA and gambogenic acid (GNA) to improve the anti-cancer efficiency in HepG2 cells. Methods: The delivery system was prepared by a two-step method. First, the GNA-anionic liposome took shape by a solvent evaporation method, and then the liposome was bound to the PEI/siRNA complex by electrostatic interaction to form the final carrier system (lipopolyplexes). Agarose gel electrophoresis, MTT, particle size and zeta potential were detected to analyse the lipopolyplexes formation. The transfection efficiency of siRNA was determined by confocal laser scanning microscopy and flow cytometry. Western blotting was used to assess the VEGF protein expression levels of HepG2 cells. The cell apoptosis assay was used to assess the anti-tumour superiority of lipopolyplexes. Results: GNA-PEI/siRNA-liposome (lipopolyplexes) are significantly less cytotoxicity compared to PEI mediated carriers. Simultaneously, the results of flow cytometry and confocal laser scanning microscopy indicated that the lipopolyplexes could successfully carry siRNA into the cytoplasm, and the western-blot result evidence that the delivery system has a potential for VEGF to express down. Also compared with the control group, the results of apoptosis test suggest that the lipopolyplexes can significantly promote cell apoptosis. Conclusion: The delivery system has a potential in the combination of various drugs for cancer therapy in future.

中文翻译：

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藤原酸和 VEGF-siRNA 与阴离子脂质体和聚乙烯亚胺复合物的共递送至 HepG2 细胞

摘要 背景与目的：将两种或两种以上不同机制的药物联合应用已成为治疗癌症的有效方法之一。本研究的目的是成功制备一种非病毒递送系统，可以有效地共同递送 siRNA 和藤原酸 (GNA)，以提高 HepG2 细胞的抗癌效率。方法：通过两步法制备递送系统。首先，GNA-阴离子脂质体通过溶剂蒸发的方法形成，然后脂质体通过静电相互作用与PEI/siRNA复合物结合，形成最终的载体系统（lipopolyplexes）。检测琼脂糖凝胶电泳、MTT、粒径和zeta电位以分析脂质复合物的形成。通过共聚焦激光扫描显微镜和流式细胞术测定siRNA的转染效率。Western印迹用于评估HepG2细胞的VEGF蛋白表达水平。细胞凋亡试验用于评估脂质复合物的抗肿瘤优势。结果：与 PEI 介导的载体相比，GNA-PEI/siRNA-脂质体（脂质复合物）的细胞毒性显着降低。同时，流式细胞术和共聚焦激光扫描显微镜的结果表明，lipopolyplexes 可以成功地将 siRNA 携带到细胞质中，并且蛋白质印迹结果证明该递送系统具有表达 VEGF 的潜力。同样与对照组相比，细胞凋亡试验结果表明脂质复合物能显着促进细胞凋亡。结论：