DNMT1 and familial pancreatic carcinoma: In addition, DNMT1‐induced hypermethylation of the miR‐34a promoter region activates the Notch signaling pathway, leading to a decrease in the sensitivity of pancreatic cancer cells to sorafenib, while treatment with decitabine, a small molecular inhibitor of DNMT1, enhances the sensitivity of pancreatic cancer cells to sorafenib.176