RESUMO
BACKGROUND: Nanomedicine, which is the application of nanotechnology in medicine to make medical diagnosis and treatment more accurate, has great potential for precision medicine. Despite some improvements in nanomedicine, the lack of efficient and low-toxic vectors remains a major obstacle. OBJECTIVE: The aim of this study was to prepare an efficient and low-toxic vector which could deliver astrocyte elevated gene-1 (AEG-1) small interfering RNA (siRNA; siAEG-1) into osteosarcoma cells effectively and silence the targeted gene both in vitro and in vivo. MATERIALS AND METHODS: We prepared a novel polysaccharide derivative by click conjugation of azidized chitosan with propargyl focal point poly (L-lysine) dendrons (PLLD) and subsequent coupling with folic acid (FA; Cs-g-PLLD-FA). We confirmed the complexation of siAEG-1and Cs-g-PLLD or Cs-g-PLLD-FA by gel retardation assay. We examined the cell cytotoxicity, cell uptake, cell proliferation and invasion abilities of Cs-g-PLLD-FA/siAEG-1 in osteosarcoma cells. In osteosarcoma 143B cells tumor-bearing mice models, we established the therapeutic efficacy and safety of Cs-g-PLLD-FA/siAEG-1. RESULTS: Cs-g-PLLD-FA could completely encapsulate siAEG-1 and showed low cytotoxicity in osteosarcoma cells and tumour-bearing mice. The Cs-g-PLLD-FA/siAEG-1 nanocomplexes were capable of transferring siAEG-1 into osteosarcoma cells efficiently, and the knockdown of AEG-1 resulted in the inhibition of tumour cell proliferation and invasion. In addition, caudal vein injecting of Cs-g-PLLD-FA/siAEG-1 complexes inhibited tumor growth and lung metastasis in tumor-bearing mice by silencing AEG-1 and regulating MMP-2/9. CONCLUSION: In summary, Cs-g-PLLD-FA nanoparticles are a promising system for the effective delivery of AEG-1 siRNA for treating osteosarcoma.
Assuntos
Neoplasias Ósseas/terapia , Moléculas de Adesão Celular/genética , Nanopartículas/química , Osteossarcoma/terapia , RNA Interferente Pequeno/administração & dosagem , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quitosana/química , Dendrímeros/química , Ácido Fólico/química , Inativação Gênica , Terapia Genética/métodos , Humanos , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Proteínas de Membrana , Camundongos Nus , Nanopartículas/administração & dosagem , Osteossarcoma/genética , Osteossarcoma/patologia , Polilisina/química , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Although amylose as a naturally-occurring helical polysaccharide has been widely used for biomedical applications, few studies have dealt with its chemical modification for non-viral gene delivery. In this work, the click modification of amylose by poly(l-lysine) dendrons was carried out and then characterized by Fourier transform infrared spectroscopy, wide-angle X-ray diffraction and elemental analyses. Such a modified polysaccharide exhibited excellent ability to condense plasmid pMSCV-GFP-PARK2 into compact and spherical nanoparticles. Moreover, it displayed much lower cytotoxicity when compared to branched polyethylenimine (bPEI, 25kDa), a commercially available gene vector. Similar to bPEI, it had a dose-dependent gene transfection activity in human embryonic kidney 293T cells, as observed by confocal laser scanning microscopy and flow cytometry. At each optimized N/P ratio, the percentage of transfected cells by this modified polysaccharide was found to be comparable to that by bPEI. Western blot and cell apoptosis analyses confirmed its effectiveness for the delivery of plasmid pMSCV-GFP-PARK2 to 293T cells.