Figure 3.

Activation of maspin expression is associated with the demethylation of its promoter in pancreatic cancer cells. Bisulfite sequencing was used to analyze cytosine methylation in six pancreatic cancer cell lines. The four unmethylated cell lines (AsPC-1, BxPC-3, Capan-2, and Capan-1) all showed activation of maspin gene expression. In contrast, two maspin-negative cell lines (Panc-1 and MiaPaCA) were heavily methylated and exhibited no maspin expression. Summary of 5-methylcytosine levels obtained by sodium bisulfite genomic sequencing of the maspin promoter. Cytosine methylation frequency histograms are shown for normal pancreas and HMECs. The x-axis is nucleotide position relative to the transcription start and the y-axis is the percent cytosine methylation.