Effect of TNF-α on nuclear transcription factor activity in mock- and KLF2-tranduced HUVECs. Nuclear activation of ATF2 (A) or p65 (B) was determined in mock- and KLF2-overexpressing HUVECs activated for 0 to 3 hours with TNF-α (10 ng/mL). Basal and TNF-α–induced ATF2 levels were strongly suppressed by KLF2, whereas basal p65 levels were not changed and TNF-α–induced p65 levels were only partially inhibited. Data are represented as mean ratios of 2 to 3 different isolates relative to the unstimulated mock condition. Error bars indicate SEM. Significant difference between mock and KLF2 values is indicated (*P < .05; **P < .01); ‡, significant difference (P < .01) between TNF-α–stimulated and unstimulated control values.