Kinetics of DMBA-mediated suppression of IL-6 mRNA levels measured byReal-time PCR. BMS2 cells were pre-treated in triplicate with vehicle (0.01% ethanol) or 1 μM DMBA 1 hour prior to challenge with 1 μg/ml LPS. At various points thereafter, cells in individual wells were harvested separately, RNA was extracted, and cytokine-specific mRNAs were quantified by real-time PCR. Data represent means ± SE of IL-6 mRNA levels (number of PCR cycles for half-maximal amplification) normalized to β-actin levels according to the Comparative CT $Method (PE Applied Biosystems) and expressed relative to maximal IL-6 levels in LPS-plus-vehicle-treated cultures at the 4 hour time point. Representative data from a total of three experiments are shown. *Statistically different than vehicle-treated controls, p < 0.02 (paired t test).