Fig. 6. COX-2 protein expression and transcription are enhanced in response to Cd. (A), (B), (C) and (D): HT-29 cells were treated with Cd (100 nM) for 6, 12, 24, 48 and 72 hours. COX-2 protein expression was assessed by western blotting. (E): Cells were treated with Cd (100 nM) for 3,6,12 and 24 hours. COX-2 transcription level was assessed by measuring the level of COX-2 promoter-driven luciferase using reporter assay. Values are the mean ± SEM of three independent experiments. * denotes p<0.05.