Fig. 1. Treatment of 5-aza-dC by limited demethylation approach preferentially demethylated specific CpG dinucleotide in PMP24 promoter CGI.
A: The organization of PMP24 promoter CGI. The major 5-aza-dC-hypersensitive site at intronic CpG 1 and 2 that corresponding to CG29 and CG30 is marked with a line. B: Relative PMP24 expression levels, as determined by real-time RT-PCR, among the normal and malignant prostate cell lines, which correlated with the extent of promoter methylation [25]. C: Treatment with 5-aza-dC reactivated PMP24 gene expression in a dose-dependent manner, with 0.1 µM the lowest concentration causing gene reactivation (n=4). D: Using the limited demethylation approach, we found one major region in PMP24 CGI that is hypersensitive to 5-aza-dC demethylation after PC-3 cells were treated briefly with a very low dose of 5-aza-dC. Figure 1A and 1D represent the same region with the same scale.