β-tan and Sal A modulate the protein levels of key AP-1 and NF-κB downstream target genes in JB6P + cells. JB6P + cells were plated in 100 mm dishes at a density of 50,000 cells/ml. At 80–90% confluency, cells were starved with 0.1% FBS for 24 h, then were pre-treated with either 10 μg/ml β-tan or 15 μg/ml Sal A for 1 h, followed by 15 min or 6 h TPA treatment. Whole cell proteins were immunoblotted with the indicated antibodies and reprobed with GAPDH antibody to ensure equal protein loading. Densitometry values were standardized relative to GAPDH for each condition and results are expressed relative to control (Ct) treated cells for each time point. Densitometry values for Bax:Bcl-2 protein ratios are indicated in italics.