FIGURE 3.

Intact Sp1 binding sites are required for miR-200b promoter activity in epithelial and mesenchymal cells. The −321/+19 wild type, ZEB, and Sp1 mutant miR-200b promoter reporters were transiently transfected into epithelial MDCK or MCF-7 (A) or mesenchymal MDCK-Pez or MDA-MB-231 (B) cells. Data are expressed as relative luciferase activity + S.E. from three independent experiments relative to the wild type −321/+19 miR-200b reporter. Statistical significance (*, p < 0.05; **, p < 0.01; ***, p < 0.001) was determined relative to indicated controls using unpaired two-tailed Student's t test.