Figure 4From: Down-regulation of human topoisomerase IIα expression correlates with relative amounts of specificity factors Sp1 and Sp3 bound at proximal and distal promoter regionsSp3 maintains transcriptional repression in the presence of Sp1. All transfections were carried out in triplicate with 1.0 μg of -617 wt topoisomerase IIα reporter plasmid and 1 μg of pCMV Sport β-galactosidase control vector. Relative luciferase activity was calculated by arbitrarily setting the control (no added Sp1 or Sp3) to 100%. Results are expressed as ± SEM where n = 9, *** p < 0.001, ** p < 0.01, and * p < 0.05Back to article page