Solid lipid nanoparticles loaded with anti-microRNA oligonucleotides (AMOs) for suppression of microRNA-21 functions in human lung cancer cells.

Purpose: Literature has highlighted the practical use of solid lipid nanoparticles (SLNs) in research, but few reports have combined SLNs with miRNA-based therapy. We aimed to prepare SLNs to load anti-miRNA oligonucleotide (AMO) for miRNA-based therapy in vitro.

Methods: SLNs were employed to encapsulate AMO by a solvent diffusion method, and then the properties of AMO-CLOSs (cationic lipid binded oligonucleotide (AMO)-loaded SLNs) were characterized. We studied cellular uptake and activation properties of AMO-CLOSs in A549 cells, including antisense efficiency, cell migration and invasion.

Results: AMO-CLOSs were 187 nm in size and 46.6 mV in zeta potential with an approximately toroid morphology in the TEM image. AMO-CLOSs uptake by A549 cells was increased significantly higher and more effective than free AMO. Further results demonstrated that AMO-CLOSs showed high antisense efficiency of microRNA-21 and subsequently decreased the proliferation, migration and invasion of tumor cells.

Conclusions: These findings suggest that AMO-CLOSs represent a potential new approach for carrying anti-miRNA inhibitors for cancer therapy.