In addition, the significance of LMP1 contributing to DNA methylation was further highlighted by a study in which over-expression of LMP1 in a NPC cell line induced expression of DNMT1 and DNMT3a/b; all these DNMTs are necessary to suppress RARβ2 via promoter hypermethylation (42). This evidence concerns the gene DNMT1 and nasopharyngeal carcinoma.