EFFECTS ON BRAIN-TUMOR CELL-PROLIFERATION BY AN ADENOVIRUS VECTOR THAT BEARS THE INTERLEUKIN-4 GENE

A recombinant adenovirus vector bearing the IL-4 gene (AD-IL-4) was us ed to infect rat glioma C6 cells in culture at multiplicity of infecti ons (MOI) from 50 to 1800. C6 cell proliferation was not altered signi ficantly by adenoviral infection. However, IL-4 production increased i n a dose-dependent manner. To ascertain effects on in vivo cell prolif eration, a subcutaneous tumor model was used. Rat C6 glioma cells alon e or C6 mixed with the control virus bearing the LacZ gene (Ad-LacZ) p roduced tumors that measured an average of approximately 3000 mm(3) 35 days after implantation. In contrast, C6 cells mixed with Ad-IL-4 pro duced significant inhibition of tumor growth (P=0.035 compared to C6 t umor; P=0.023 compared to C6+Ad-LacZ tumor. Student's t test). IL-4 le vels in mice serum were measured by ELISA and reached a peak of approx imately 700 pg/ml at 14 days. These preliminary results showed that ad enovirus-mediated delivery of the IL-4 gene may result in a significan t inhibition of rat C6 cell tumor growth. Further studies will be nece ssary to refine this anti-tumor effect for as a potential therapy for cancer.