Ad5/35-tk-mediated enhancement of in vitro cytotoxicity in bladder cancer cells. CD46-overexpressing (CD46), CD46-suppressed (shCD46), or control EJ bladder cancer cells (veh) were seeded into 24-well plates and cultured overnight. Subsequently, the cells were either left untransduced or were transduced with Ad5-tk or Ad5/35-tk at the indicated MOIs of 5 and 20. The following day, increasing concentrations of GCV were added and an MTT in vitro proliferation assay was performed five days post-infection. Bladder cancer cells used in this experiment are EJ (A), 5637 (B), J82 (C), T24 (D), and HT-1376 (E). The error bars represent SEM. Statistics: p < 0.05 by two-way ANOVA.