RT-PCR and Western blotting analysis of mouse Ad-ETK transgene and protein expression. (A) RT-PCR was performed on hepatic carcinoma tissue isolated from a mouse infected with Ad-ETK. Lanes: M, 2000 bp DNA maker; 1−5, E1A of saline, GCV, Ad, Ad-ETK, and Ad-ETK/GCV groups, respectively; 6−10, TK of saline, GCV, Ad, Ad-ETK, and Ad-ETK/GCV groups, respectively; 11–15, β-actin of saline, GCV, Ad, Ad-ETK, and Ad-ETK/GCV groups, respectively. (B) Western blotting analysis of E1A and TK expression in tumors. Protein extracted from HepG2 tumors was subjected to Western blotting using antibodies to E1A, TK, and ERK. Lanes: 1, Saline group; 2, GCV group; 3, Ad group; 4, Ad-ETK group; and 5, Ad-ETK/GCV group.