Figure 4.

Transcriptional activation of COX-2 by PGE₂ and PGE₃. NIH 3T3 fibroblasts were transiently transfected, with WT COX-2 reporter construct (A) or with either WT COX-2 promoter or mutant COX-2 promoter constructs (B) or cotransfected with WT COX-2 reporter and a control plasmid or plasmids expressing DN-Ras, DN-JNK, or DN-ERK1 (C). The transfected cells were treated with serum (20%), PGE₂, or PGE₃ at the concentrations indicated. Cells were harvested after 6 h and assayed for luciferase activity and total protein. Values are means ± SD. *, P < 0.05 vs. PGE₂ treatment.