Adenovirus vectors with chimeric type 5 and 35 fiber proteins exhibit enhanced transfection of human pancreatic cancer cells

Adenovirus (Ad) vectors are widely used for gene transfer. Efficient gene transfer into malignant cells is an important requirement for anticancer gene therapy, but transgene expression after transfer with adenoviral vectors varies among different cancer cell lines. Recently, Ad vectors containing chimeric type 5 and 35 fiber proteins have been developed. We evaluated the expression of coxsackie and adenovirus receptor (CAR), as well as integrins αV, β3 and β5, in seven human pancreatic cancer cell lines and assessed the relationship between expression of these molecules and Ad transfection efficiency. We compared the transfection efficiency of a conventional type 5 Ad vector (Ad5GFP) with that of an Ad vector containing chimeric type 5 and 35 fiber proteins (Ad5/35GFP), which expressed green fluorescent protein (GFP) driven by the cytomegalovirus promoter. There was strong CAR expression by AsPC-1, CFPAC-1 and PANC-1 cells, whereas the other cell lines showed weak expression. There was strong integrin β3 expression by MIAPaCa-2, PANC-1 and Suit-2 cells, but expression by AsPC-1, BxPC-3, CFPAC-1 and HPAC cells was weak. Transfection efficiency of the vectors for human pancreatic cancer cell lines was not directly related to the CAR or integrin expression. However, transfection by Ad5/35GFP was significantly greater than by Ad5GFP at MOIs of 10 and 25 in all five human pancreatic cell lines. In conclusion, the Ad5/35GFP vector mediates more efficient gene transfer to human pancreatic cancer cells. These results may have implications for improving the efficiency of Ad-mediated gene transfer and developing adenoviral vectors.