biostudies-literatureUnknown3(2)Cheng YB<i>N</i>-methyl-<i>N</i>'-nitro-<i>N</i>-nitrosoguanidine (MNNG) is an alkylating agent that can induce gastric carcinoma. As a well-known human carcinogen, MNNG has been universally recognized as a methylating agent and is believed to act through methylation mechanism. In the present study, the epigenetic status of the human telomerase reverse transcriptase (hTERT) promoter was investigated in MNNG-treated normal human gastric mucosal epithelial cells. After 4 h exposure to MNNG at different concentrations, 6.8 and 68 µM, bisulfite sequencing polymerase chain reaction showed that five methylated cytosines outside the CpG dinucleotides in the 290-bp fragment from the hTERT promoter were demethylated and all the methylated cytosines in CpG dinucleotides remained intact. Furthermore, the epiBiomedical reports176-178https://www.ebi.ac.uk/biostudies/studies/S-EPMC4360657biostudies-literatureDemethylation of the hTERT promoter in normal human gastric mucosal epithelial cells following <i>N</i>-methyl-<i>N</i>'-nitro-<i>N</i>-nitrosoguanidine exposure.PMC4360657Yao PGuo LPFang DCCheng YBNing XYWang LfalseDemethylation of the hTERT promoter in normal human gastric mucosal epithelial cells following <i>N</i>-methyl-<i>N</i>'-nitro-<i>N</i>-nitrosoguanidine exposure.<i>N</i>-methyl-<i>N</i>'-nitro-<i>N</i>-nitrosoguanidine (MNNG) is an alkylating agent that can induce gastric carcinoma. As a well-known human carcinogen, MNNG has been universally recognized as a methylating agent and is believed to act through methylation mechanism. In the present study, the epigenetic status of the human telomerase reverse transcriptase (hTERT) promoter was investigated in MNNG-treated normal human gastric mucosal epithelial cells. After 4 h exposure to MNNG at different concentrations, 6.8 and 68 µM, bisulfite sequencing polymerase chain reaction showed that five methylated cytosines outside the CpG dinucleotides in the 290-bp fragment from the hTERT promoter were demethylated and all the methylated cytosines in CpG dinucleotides remained intact. Furthermore, the epi2015-01-01T00:00:00Z2015 Mar2025-04-22T19:54:45.367Z2019-06-06T14:07:49ZS-EPMC43606572579824410.3892/br.2014.398