DNMT1 and exocrine pancreatic carcinoma: Zebularine is a highly stable hydrophilic DNA methylation inhibitor [19], which preferentially depletes DNA methyltransferase 1 (DNMT1), as demonstrated in bladder, prostate, lung, colon, and pancreatic carcinoma cell lines [20], often resulting in inhibition of cell proliferation and induction of apoptosis [21], [22].