PURPOSE: The methylation of high-in-normal-1 (HIN-1) gene promoter in undifferentiated nasopharyngeal carcinoma (NPC) is studied. EXPERIMENTAL DESIGN: The methylation status of HIN-1 in NPC cell lines, primary NPC, paired nasopharyngeal swabs, paired throat-rinsing fluid, and paired peripheral blood was assessed by methylation-specific PCR assay. The relationship between HIN-1 promoter methylation and transcription in NPC cell lines was evaluated by reverse transcription-PCR and demethylation agent treatment (5-aza-2-deoxycytidine). RESULTS: Hypermethylated promoter was observed in five of five (100%) NPC cell lines and not found in three normal nasopharyngeal outgrowths, two tonsil epithelial cell cultures, and two skin fibroblast cultures. Reverse transcription-PCR assay indicated that HIN-1 transcription was significantly down-regulated in the NPC cell line with promoter methylation. Treatment with demethylation agent, 5-aza-2-deoxycytidine, restored HIN-1 transcription in the NPC cell line. Methylated HIN-1 promoter was found in 36 of 47 (77%) primary NPC tumors and not found in the normal nasopharyngeal biopsies. Methylated HIN-1 promoter was detected in 12 of 26 (46%) nasopharyngeal swabs, 5 of 26 (19%) throat-rinsing fluids, 2 of 11 (18%) plasmas, and 5 of 11 (46%) buffy coats of peripheral blood of the NPC patients but was not detectable in all normal controls. CONCLUSION: HIN-1 promoter hypermethylation is common in NPC. Methylated promoter DNA in nasopharyngeal swab, throat-rinsing fluid, and peripheral blood might be potentially useful as tumor marker for screening of NPC.
PURPOSE: The methylation of high-in-normal-1 (HIN-1) gene promoter in undifferentiated nasopharyngeal carcinoma (NPC) is studied. EXPERIMENTAL DESIGN: The methylation status of HIN-1 in NPC cell lines, primary NPC, paired nasopharyngeal swabs, paired throat-rinsing fluid, and paired peripheral blood was assessed by methylation-specific PCR assay. The relationship between HIN-1 promoter methylation and transcription in NPC cell lines was evaluated by reverse transcription-PCR and demethylation agent treatment (5-aza-2-deoxycytidine). RESULTS: Hypermethylated promoter was observed in five of five (100%) NPC cell lines and not found in three normal nasopharyngeal outgrowths, two tonsil epithelial cell cultures, and two skin fibroblast cultures. Reverse transcription-PCR assay indicated that HIN-1 transcription was significantly down-regulated in the NPC cell line with promoter methylation. Treatment with demethylation agent, 5-aza-2-deoxycytidine, restored HIN-1 transcription in the NPC cell line. Methylated HIN-1 promoter was found in 36 of 47 (77%) primary NPC tumors and not found in the normal nasopharyngeal biopsies. Methylated HIN-1 promoter was detected in 12 of 26 (46%) nasopharyngeal swabs, 5 of 26 (19%) throat-rinsing fluids, 2 of 11 (18%) plasmas, and 5 of 11 (46%) buffy coats of peripheral blood of the NPC patients but was not detectable in all normal controls. CONCLUSION:HIN-1 promoter hypermethylation is common in NPC. Methylated promoter DNA in nasopharyngeal swab, throat-rinsing fluid, and peripheral blood might be potentially useful as tumor marker for screening of NPC.
Authors: Jolly Mazumdar; Michele M Hickey; Dhruv K Pant; Amy C Durham; Alejandro Sweet-Cordero; Anil Vachani; Tyler Jacks; Lewis A Chodosh; Joseph L Kissil; M Celeste Simon; Brian Keith Journal: Proc Natl Acad Sci U S A Date: 2010-07-21 Impact factor: 11.205
Authors: M Herranz; M E Padín-Iruegas; Nieves Martínez-Lago; S Aguín Losada; P Raña-Díez; E Brozos Vázquez; J J Carrera; J R Antúnez; A Ruibal; R López-López Journal: Mol Neurobiol Date: 2015-03-11 Impact factor: 5.590