AD55-Apoptin showed the selective anti-hepatoma effect in a time-dependent manner. A. Tumor cells (Huh7, PLC, Hep3B, HepG2) were infected with ONYX-015, AD55 and AD55-Apoptin at the MOI of 10 for 1,2,3,4 days, respectively. At the indicated time, cell viability was determined by MTT assay. B. According to the above similar method, the cell viability of normal cells infected with various viruses was detected by MTT assay. Datas are presented as means ± SD (error bars) of triplicate experiments.