DNMT1 and pancreatic neoplasm: Complementary knockdown experiments using 2 specific Nupr1 siRNAs to transfect pancreatic cancer cells (MiaPaCa2) decreased Dnmt1 mRNA levels (3.8 fold ± 0.7; p < 0.01), without affecting either Dnmt3a or Dnmt3b expression (Fig. 1B).