Kim Hyun Ah, Nam Kihoon, Kim Sung Wan
Center for Controlled Chemical Delivery (CCCD), Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA.
Center for Controlled Chemical Delivery (CCCD), Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA; Department of Bioengineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, South Korea.
Biomaterials. 2014 Aug;35(26):7543-52. doi: 10.1016/j.biomaterials.2014.05.021. Epub 2014 Jun 2.
Targeted delivery of therapeutic genes to the tumor site is critical for successful and safe cancer gene therapy. The arginine grafted bio-reducible poly (cystamine bisacrylamide-diaminohexane, CBA-DAH) polymer (ABP) conjugated poly (amido amine) (PAMAM), PAM-ABP (PA) was designed previously as an efficient gene delivery carrier. To achieve high efficacy in cancer selective delivery, we developed the tumor targeting bio-reducible polymer, PA-PEG1k-RGD, by conjugating cyclic RGDfC (RGD) peptides, which bind αvβ3/5 integrins, to the PAM-ABP using polyethylene glycol (PEG, 1 kDa) as a spacer. Physical characterization showed nanocomplex formation with bio-reducible properties between PA-PEG1k-RGD and plasmid DNA (pDNA). In transfection assays, PA-PEG1k-RGD showed significantly higher transfection efficiency in comparison with PAM-ABP or PA-PEG1k-RAD in αvβ3/5 positive MCF7 breast cancer and PANC-1 pancreatic cancer cells. The targeting ability of PA-PEG1k-RGD was further established using a competition assay. To confirm the therapeutic effect, the VEGF siRNA expressing plasmid was constructed and then delivered into cancer cells using PA-PEG1k-RGD. PA-PEG1k-RGD showed 20-59% higher cellular uptake rate into MCF7 and PANC-1 than that of non-targeted polymers. In addition, MCF7 and PANC-1 cancer cells transfected with PA-PEG1k-RGD/pshVEGF complexes had significantly decreased VEGF gene expression (51-71%) and cancer cell viability (35-43%) compared with control. These results demonstrate that a tumor targeting bio-reducible polymer with an anti-angiogenic therapeutic gene could be used for efficient and safe cancer gene therapy.
将治疗性基因靶向递送至肿瘤部位对于成功且安全的癌症基因治疗至关重要。先前设计了精氨酸接枝的生物可还原聚（胱胺双丙烯酰胺 - 二氨基己烷，CBA - DAH）聚合物（ABP）共轭聚（酰胺胺）（PAMAM），即PAM - ABP（PA），作为一种高效的基因递送载体。为了在癌症选择性递送中实现高效，我们通过使用聚乙二醇（PEG，1 kDa）作为间隔物，将结合αvβ3/5整合素的环状RGDfC（RGD）肽与PAM - ABP共轭，开发了肿瘤靶向生物可还原聚合物PA - PEG1k - RGD。物理表征显示PA - PEG1k - RGD与质粒DNA（pDNA）之间形成了具有生物可还原特性的纳米复合物。在转染试验中，与PAM - ABP或PA - PEG1k - RAD相比，PA - PEG1k - RGD在αvβ3/5阳性的MCF7乳腺癌细胞和PANC - 1胰腺癌细胞中显示出显著更高的转染效率。使用竞争试验进一步证实了PA - PEG1k - RGD的靶向能力。为了确认治疗效果，构建了表达VEGF siRNA的质粒，然后使用PA - PEG1k - RGD将其递送至癌细胞中。PA - PEG1k - RGD在MCF7和PANC - 1细胞中的细胞摄取率比非靶向聚合物高20 - 59％。此外，与对照相比，用PA - PEG1k - RGD/pshVEGF复合物转染的MCF7和PANC - 1癌细胞的VEGF基因表达显著降低（51 - 71％），癌细胞活力也显著降低（35 - 43％）。这些结果表明，具有抗血管生成治疗基因的肿瘤靶向生物可还原聚合物可用于高效且安全的癌症基因治疗。
