Transcriptional activity of the rat proximal HL promoter region in HepG2 and HeLa cells. HepG2 (hatched bars) and HeLa cells (open bars) were transiently transfected with the indicated promoter-reporter constructs. At 48 h post-transfection, transcriptional activity was determined as the ratio of CAT over β-galactosidase expression level. Data are expressed as percentage of the ratio measured in the rHL-39 CAT – transfected cells. Data are means ± SD from 3 independent experiments, each performed in triplicate. *,+: P < 0.05 compared to 100% in HepG2 and HeLa cells, respectively.