Characterization of ZD55-TRAIL-IETD-Smac and its selective replication in tumor cells. (A) A schematic drawing of the oncolytic adenovirus ZD55-TRAIL-IETD-Smac and other recombinant adenoviruses. ITR, inverted terminal repeat. (B) Identification of various recombinant adenoviruses by Western blot analysis. Bel-7404 cells were treated with ZD55, ZD55-TRAIL, ZD55-Smac, and ZD55-TRAIL-IETD-Smac at an MOI of 10, or with ZD55-TRAIL combined with ZD55-Smac at an MOI of 5. After 48 hr, cell lysates were prepared for analyzing the expression of TRAIL, Smac, and E1A proteins. Mock-infected cells were included as a control. β-Actin was used as a protein loading control. (C) E1A protein expression in normal human liver cells (QSG-7701) was detected by Western blotting after treatment with various recombinant adenoviruses at the dose described previously. Data are from three independent experiments.