Highly efficient gene silencing and bioimaging based on fluorescent carbon dots in vitro and in vivo
Small interfering RNA (siRNA) is an attractive therapeutic candidate for sequence-specific gene silencing to treat incurable diseases using small molecule drugs. However, its efficient intracellular delivery has remained a challenge. Here, we have developed a highly biocompatible fluorescent carbon dot (CD), and demonstrate a functional siRNA delivery system that induces efficient gene knockdown in vitro and in vivo. We found that CD nanoparticles (NPs) enhance the cellular uptake of siRNA, via endocytosis in tumor cells, with low cytotoxicity and unexpected immune responses. Real-time study of fluorescence imaging in live cells shows that CD NPs favorably localize in cytoplasm and successfully release siRNA within 12 h. Moreover, we demonstrate that CD NP-mediated siRNA delivery significantly silences green fluorescence protein (GFP) expression and inhibits tumor growth in a breast cancer cell xenograft mouse model of tumor-specific therapy. We have developed a multifunctional siRNA delivery vehicle enabling simultaneous bioimaging and efficient downregulation of gene expression, that shows excellent potential for gene therapy.
Keywordsbioimaging carbon dot gene delivery RNA interference targeted cancer therapy
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This work was supported by the Basic Science Research Program (Nos. 2011-0017356 and 2011-0020322), International S&T Cooperation Program (No. 2014K1B1A1073716) and the Research Center Program (No. IBS-R008-D1) of IBS (Institute for Basic Science) through the National Research Foundation of Korea (NRF) funded by the Korean government (MEST).
- Niikura, K.; Kobayashi, K.; Takeuchi, C.; Fujitani, N.; Takahara, S.; Ninomiya, T.; Hagiwara, K.; Mitomo, H.; Ito, Y.; Osada, Y. et al. Amphiphilic gold nanoparticles displaying flexible bifurcated ligands as a carrier for siRNA delivery into the cell cytosol. ACS Appl. Mater. Interfaces 2014, 6, 22146–22154.CrossRefGoogle Scholar
- Ngamcherdtrakul, W.; Morry, J.; Gu, S. D.; Castro, D. J.; Goodyear, S. M.; Sangvanich, T.; Reda, M. M.; Lee, R.; Mihelic, S. A.; Beckman, B. L. et al. Cationic polymer modified mesoporous Silica nanoparticles for targeted siRNA delivery to HER2+ breast cancer. Adv. Funct. Mater. 2015, 25, 2646–2659.CrossRefGoogle Scholar
- Huang, P.; Lin, J.; Wang, X. S.; Wang, Z.; Zhang, C. L.; He, M.; Wang, K.; Chen, F.; Li, Z. M.; Shen, G. X. et al. Light-triggered theranostics based on photosensitizerconjugated carbon dots for simultaneous enhancedfluorescence imaging and photodynamic therapy. Adv. Mater. 2012, 24, 5104–5110.CrossRefGoogle Scholar
- Bieber, T.; Elsä sser, H. P. Preparation of a low molecular weight polyethylenimine for efficient cell transfection. Biotechniques 2001, 30, 74–77, 80–81.Google Scholar