MATERIALS AND METHODS: Experiments were performed in accordance with National Institutes of Health guidelines for the care and use of laboratory animals and were approved by the animal research committee at Seoul National University Hospital. VX2
carcinoma was implanted into the liver of 26 rabbits. Four nonviral gene transfer systems were prepared by using pCMV-luc+ as a reporter gene. The first system consisted of
a DNA and
polyethylenimine (PEI) complex (n = 7); the second, of
a DNA and PEI complex mixed with
iopamidol and
iodized oil (n = 7); the third, of
a DNA and PEI complex mixed with
iopamidol (n = 7); and the fourth, of
a DNA and PEI complex mixed with
iodized oil (n = 5). For the
DNA and PEI complex that was mixed with
iopamidol and
iodized oil,
iopamidol was used to stabilize the
emulsion. Twenty days after
tumor implantation, intraarterial gene delivery was performed by selective catheterization of the hepatic artery. Rabbits were euthanized 24 hours after gene delivery.
Luciferase activity was assayed in the
tumor, left hepatic lobe, right hepatic lobe, and other organs and was statistically analyzed for comparison between complexes by using the Kruskal-Wallis test.
RESULTS:
Luciferase activity in the
tumor was significantly higher for the group that received
DNA, PEI,
iopamidol, and
iodized oil than for any other group (Kruskal-Wallis test, P < .05).
Luciferase activity in the left hepatic lobe, right hepatic lobe, and other organs was not significantly different between complexes. Selective gene expression in
tumor cells was confirmed by means of immunohistochemical analysis for
luciferase.
CONCLUSION: