Increased CXCR4 expression was achieved with the knock-down of DNA methyltransferase 1 (DNMT1) or DNA methyltransferase 3 beta (DNMT3B), or with the inhibition of DNA methylation by 5-aza-2-deoxycytidine (5-aza) in pancreatic cancer cells [49]. Here, DNMT3B is linked to familial pancreatic carcinoma.