Liposomal magnetofection potentiates gene transfection by applying a magnetic field to concentrate magnetic lipoplexes onto target cells. Magnetic lipoplexes are self-assembling ternary complexes of cationic
lipids with plasmid
DNA associated with superparamagnetic iron oxide nanoparticles (SPIONs). Type1
insulin-like growth factor receptor (IGF-1R), an important oncogene, is frequently overexpressed in
lung cancer and mediates
cancer cell proliferation and
tumor growth. In this study, we evaluated the transfection efficiency (percentage of transfected cells) and therapeutic potential (potency of IGF-1R knockdown) of liposomal magnetofection of plasmids expressing GFP and shRNAs targeting IGF-1R (pGFPshIGF-1Rs) in A549 cells and in
tumor-bearing mice as compared to lipofection using
Lipofectamine 2000. Liposomal magnetofection provided a threefold improvement in transgene expression over lipofection and transfected up to 64.1% of A549 cells in vitro. In vitro, IGF-1R specific-
shRNA transfected by lipofection inhibited IGF-1R
protein by 56.1±6% and by liposomal magnetofection by 85.1±3%. In vivo delivery efficiency of the pGFPshIGF-1R plasmid into the
tumor was significantly higher in the liposomal magnetofection group than in the lipofection group. In vivo IGF-1R specific-
shRNA by lipofection inhibited IGF-1R
protein by an average of 43.8±5.3%; that by liposomal magnetofection inhibited IGF-1R
protein by 43.4±5.7%, 56.3±9.6%, and 72.2±6.8%, at 24, 48, and 72 h, respectively, after pGFPshIGF-1R injection. Our findings indicate that liposomal magnetofection may be a promising method that allows the targeting of gene therapy to
lung cancer.