Verification of Sp1 binding at the <i>hTFF3</i> promoter.

<p>A. ChIP assay: LS174T cells were fixed with formalin, and then the chromatin was cleaved by sonication. The cleaved chromatin was then incubated with an anti-Sp1 antibody, a positive control RNA polII antibody, and a negative control IgG antibody. Finally, Sp1 binding at the <i>hTFF3</i> promoter was assessed by PCR amplification. B. HEK293 or LS174T cells were co-transfected with pGL3-300 and pRL-TK, and then treated with different concentrations of mithramycin A (a Sp1 inhibitor) for 24 h. Relative luciferase activity was measured and calculated. Data are presented as the mean ± SD (*P<0.05 <i>vs</i>. 0 µM mithramycin A).