Fig. 10. Effect of wild-type and mutated p53 overexpression on HIF-1 transcriptional activity in HepG2 cells. Cells were incubated for 16 hours under normoxia or hypoxia. Cells were cotransfected with pGL3-6HRE (A) or pG13-Luc (B), p53 expression plasmid or pCMV-myc and pRL. HIF-1 or p53 activity is expressed as the ratio of firefly luciferase to Renilla luciferase activity (means ± 1 s.d., n=3). ^*P<0.05, ^**P<0.01 or ^***P<0.001 vs. normoxia; (^***)P<0.001 or (NS), not significant vs. hypoxia.