De igual manera, defectos en la DNMT se han visto asociados con la aparicion y progresion de tumores-- hepaticos, pancreaticos, pulmonares, uroteliales, gastricos, uterino-cervicales, de seno (121) y esofagicos (122)-.
Cytosine DNA methylation, taking place on cytosines within the CpG dinucleotide sequence, is a process catalyzed by DNA methyltransferases (DNMTs) enzymes, and is a key epigenetic mechanism associated to gene expression modulation.
(34) In the current study, the demethylation effect and molecular mechanisms of a DNMT enzyme inhibitor, known as 5-Aza-CdR, on the PANC-1 cell line showed the same results as Pfeifer; that concentrations of 5 and 10 |JM were more effective.
 studied the hypoxic response in human lamina cribrosa cells and found that hypoxia significantly increased expression of DNMT and the levels of global DNA methylation when compared to the normoxic lamina cribrosa cells.
DNA methylation is catalyzed by a family of enzymes named DNA methyltransferases (DNMTs), which transfer a methyl group from S-adenosyl methionine (SAM) to the fifth carbon of cytosine at the dinucleotide CpG.
The involvement of HBV infection in epigenetic alternations during hepatocarcinogenesis has been described; HBV X (HBx) protein expression promoted DNA methyltransferase (DNMT) activity by upregulation of DNMT1, DNMT3A1, and DNMT3A2 and selectively facilitated regional hypermethylation of specific tumor suppressor genes .