Egr-1 activity in the presence of inhibitor PD98059.

TF-1 cells (2 × 10⁷) were transfected with the −116 CAT/egr-1 construct in the absence or presence of 20 μmol/L PD98059, depicted by the white or hatched bars, respectively. The left panel displays experiments stimulated with GM-CSF, and the right panel for those with TPA. There was a statistically significant decrease in fold induction in the presence of inhibitor on GM-CSF stimulation, having a P value of .0183 (A), but there was no difference noted with TPA activation (B). This was the average of 4 independent experiments performed in triplicate.