Gene transfer into solid tumours--is a special application device beneficial?

The replacement of inactivated tumour suppressor genes is a promising approach in cancer therapy. The aim of this study was to evaluate the influence of technical determinants on the efficiency of adenoviral-mediated gene transfer into solid tumours. Therefore, we compared the efficacy of two different injection needle types, a conventional needle and a modified needle characterised by perforations at the side of the shaft in vivo. The total amount of adenoviral vector DNA and the activity of the transferred reporter gene were quantitatively analysed by polymerase chain reaction (PCR) specific for the E4 region of the Ad vector genome and the beta-galactosidase assay, respectively. The levels of adenoviral DNA, as well as the total beta-galactosidase activity, varied widely, but were not significantly different for the two groups. These results suggest, that the efficiency of intratumoral gene transfer cannot be improved by the design of the application device.