Basal and inducible expression of NF-κB target genes modulated by TNF-α. UM-SCC 6 cells were treated with TNF-α (2000 units/ml) for different times. Total RNA was isolated, and genes selected from NF-κB networks or pathways were analyzed by real time RT-PCR. The data are presented as the mean plus standard deviation from triplicates with normalization by 18S ribosome RNA. *P < 0.05 compared with the control (t test).