Replication-competent adenoviruses (Ad) produced cytotoxic effects on infected tumors and have been examined for the clinical applicability. A biomarkers to predict the cytotoxicity is valuable in a clinical setting. | Cytotoxicity of replication-competent adenoviruses powered by an exogenous regulatory region is not linearly correlated with the viral infectivity gene expression or with the E1A-activating ability but is associated with the p53 genotypes