Peng Shu-Fen, Hsu Hung-Kun, Lin Chun-Cheng, Cheng Ya-Ming, Hsu Kuang-Hsing
Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan.
Department of Medical Research, China Medical University Hospital, Taichung 40402, Taiwan.
Molecules. 2017 Jan 4;22(1):86. doi: 10.3390/molecules22010086.
The efficient delivery of sufficient amounts of nucleic acids into target cells is critical for successful gene therapy and gene knockdown. The DNA/siRNA co-delivery system has been considered a promising approach for cancer therapy to simultaneously express and inhibit tumor suppressor genes and overexpressed oncogenes, respectively, triggering synergistic anti-cancer effects. Polyethylenimine (PEI) has been identified as an efficient non-viral vector for transgene expression. In this study, we created a very high efficient DNA/siRNA co-delivery system by incorporating a negatively-charged poly-γ-glutamic acid (γ-PGA) into PEI/nucleic acid complexes. Spherical nanoparticles with about 200 nm diameter were formed by mixing PEI/plasmid DNA/siRNA/γ-PGA (dual delivery nanoparticles; DDNPs) with specific ratio (N/P/C ratio) and the particles present positive surface charge under all manufacturing conditions. The gel retardation assay shows both nucleic acids were effectively condensed by PEI, even at low N/P ratios. The PEI-based DDNPs reveal excellent DNA/siRNA transfection efficiency in the human hepatoma cell line (Hep 3B) by simultaneously providing high transgene expression efficiency and high siRNA silencing effect. The results indicated that DDNP can be an effective tool for gene therapy against hepatoma.
将足量核酸有效递送至靶细胞对于成功进行基因治疗和基因敲低至关重要。DNA/小干扰RNA（siRNA）共递送系统被认为是一种很有前景的癌症治疗方法，可分别同时表达和抑制肿瘤抑制基因及过表达的癌基因，从而触发协同抗癌效应。聚乙烯亚胺（PEI）已被确定为一种用于转基因表达的高效非病毒载体。在本研究中，我们通过将带负电荷的聚γ-谷氨酸（γ-PGA）掺入PEI/核酸复合物中，创建了一种高效的DNA/siRNA共递送系统。通过以特定比例（N/P/C比）混合PEI/质粒DNA/siRNA/γ-PGA（双递送纳米颗粒；DDNPs）形成直径约200 nm的球形纳米颗粒，且在所有制备条件下颗粒均呈现正表面电荷。凝胶阻滞试验表明，即使在低N/P比下，两种核酸也能被PEI有效凝聚。基于PEI的DDNPs通过同时提供高转基因表达效率和高siRNA沉默效果，在人肝癌细胞系（Hep 3B）中显示出优异的DNA/siRNA转染效率。结果表明，DDNP可能是一种用于肝癌基因治疗的有效工具。
