In Epstein-Barr virus infected nasopharyngeal carcinoma (EBV-NPC) cells, EBV latent membrane protein 1(LMP1) upregulates DNA methyltransferase 3b (DNMT3b) transcription in a NF-kB p65-dependent-manner, thereby resulting in relatively higher methylation intensity at PTEN CpG islands, and ultimately suppressing PTEN protein expression [38]. Here, DNMT3B is linked to nasopharyngeal carcinoma.