Overexpression of full-length EGR-1, but not a transcriptionally inactive mutant, results in activation of the TF promoter in HUVEC. EGR-1–mediated activation of the TF promoter is prevented by deletion of the Sp1/EGR-1 sites. Luciferase activity of wild-type (wt, white bars) or deleted (▵Sp1/EGR-1, black bars) reporter constructs in the presence of the EGR-1 expression plasmid or the inactive mutant (mEGR-1) was calculated relative to the wt promoter activity (mean ± SD from three independent experiments performed in duplicates; *P < .01 versus basal wt activity).