Figure 3.

DNA demethylation of specific CpG sites within the human MMP9 promoter region in vitro. (A) Identification of 12 CpG sites within the promoter region of human MMP9 gene. (B) MMP9 promoter demethylation levels were assessed by bisulfite sequencing PCR.*P<0.05 vs. NG. (C) In vitro methylation of human MMP9 promoter region decreased its promoter activity, as detected by a luciferase reporter assay. Luciferase activity was measured following transfection of 293T cells with the unmethylated or methylated pGL3 Basic MMP9 plasmid. *P<0.05 vs. unmethylated pGL3-MMP9 plasmid. MMP9, matrix metalloproteinase 9.