To determine whether the downregulation of ZNF671 results from its promoter hypermethylation, immortalized normal nasopharyngeal epithelial cell line and NPC cell lines were treated with or without the demethylation drug 5-aza-2′-deoxycytidine (Decitabine, DAC). The gene discussed is ZNF671; the disease is nasopharyngeal carcinoma.