Evaluation of gas-filled microparticles and sonoporation as gene delivery system: feasibility study in rodent tumor models

Item Type:	Article
Title:	Evaluation of gas-filled microparticles and sonoporation as gene delivery system: feasibility study in rodent tumor models
Creators Name:	Hauff, P. and Seemann, S. and Reszka, R. and Schultze-Mosgau, M. and Reinhardt, M. and Buzasi, T. and Plath, T. and Rosewicz, S. and Schirner, M.
Abstract:	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 -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 tumors (adenocarcinoma of the human pancreas) by using the plasmid RC/CMV-p16 (pRC/CMV-p16), which contains tumor suppressor gene p16. The tumor suppressor gene p16 is deleted in Capan-1 cells. Twenty-five tumor-bearing mice were classified into five groups (four to six mice per group, one treatment group, four control groups) at random. All mice were treated once weekly for 5 weeks with intravenous infusion of p76-containing GFMP or control substances with simultaneous tumor sonication with color Doppler mode ultrasound and maximum mechanical index or without ultrasound treatment. The therapeutic effect of p16 was measured as an increase in tumor volume doubling time. Data were analyzed with analysis of variance. Results were considered significant at the 5% critical level (P < .05). RESULTS: A clear expression of pDNA was found in tumors in rats treated with a combination of pUT651-containing GFMP and ultrasound; relevant controls showed a significantly lower expression of marker gene. The controlled ultrasound-triggered release of pRC/CMV-p16 from GFMP leads to a strong tumor growth inhibition, which is significant (P < .002), compared with that in controls. CONCLUSION: A combination of GFMP and ultrasound provides an effective approach for nonviral gene therapy-based cancer treatment.
Keywords:	Animal Disease Models, Feasibility Studies, Gases, Gene Therapy, Neoplasms, Animals, Rats
Source:	Radiology
ISSN:	0033-8419
Publisher:	Radiology Soc North America
Volume:	236
Number:	2
Page Range:	572-578
Date:	1 August 2005
Official Publication:	https://doi.org/10.1148/radiol.2362040870
PubMed:	View item in PubMed

Repository Staff Only: item control page