Pharmacological inhibition of P-selectin expression does not require the presence of an intact κB element in the human P-selectin promoter. BAEC were transfected with a luciferase reporter gene driven by the human P-selectin 5′ flanking sequence from −309 to −13 (A) or with a reporter gene driven by the same 5′ flanking sequence with the exception of a 2-nucleotide mutation in the κB element (B). After 36 hours, the cells were pretreated for 1 hour at 37°C in the presence or absence of 25 μmol/L ALLN, 100 μmol/L PDTC, 5 mmol/L NaSal, 1 μmol/L dexamethasone (Dex), 25 μmol/L ALLM, 25 μmol/L Indo, or the diluents EtOH or DMSO used for dexamethasone and ALLN, respectively. The cells were then incubated without cytokine for 12 hours, with 100 U/mL TNF-α for 4 hours, or with 10 ng/mL of boiled or active OSM for 12 hours. The luciferase activities in cell lysates were then measured; the values were normalized, with a value of 1.0 assigned to unstimulated cells incubated in the absence of pharmacological agent. The data represent the mean ± SD of triplicate transfections from each of two independent experiments.