Evaluation of Gas-filled Microparticles and Sonoporation as Gene Delivery System: Feasibility Study in Rodent Tumor Models

PURPOSE: To evaluate the feasibility of gene delivery mediated with diagnostic ultrasound and plasmid DNA (pDNA) encapsulated in gas-filled microparticles (GFMP) in rodent tumor models. MATERIALS AND METHODS: This study was performed according to a protocol approved by the regional animal research committee. The model plasmid UT651 (pUT651) that contained the Escherichia coli LacZ gene for β-galactosidase was used to demonstrate the feasibility of ultrasound-mediated gene delivery in CC531 liver tumors in rats. In preliminary experiments, a single injection of pUT651-containing GFMP was administered intraarterially (n = 4) or intravenously (n = 6) with simultaneous sonication (color Doppler mode, maximum mechanical index) of the GFMP passing through the capillaries of the tumors. All animals were sacrificed 2–5 days later, and liver tumors were examined for β-galactosidase expression histochemically. Subsequently, potential medical usefulness of this delivery system was tested in nude mice bearing Capan-1...