Silence of HIN-1 expression through methylation of its gene promoter in gastric cancer

Figure 1 Silence of high in normal-1 gene expression due to methylation of high in normal-1 gene promoter in gastric carcinoma cell lines. A: Methylation-specific polymerase chain reaction analysis of high in normal-1 (HIN-1) gene promoter methylation in five gastric carcinoma cell lines. U: Unmethylated alleles; M: Methylated alleles. In vitro methylated DNA (IVD) and DNA from normal human peripheral lymphocytes were used as methylated and unmethylated controls; B: Gastric cancer cell lines were treated with or without 5-aza-CdR (-AZ) for up to 96 h. HIN-1 mRNA levels were measured by semi-quantitative reverse transcription polymerase chain reaction analysis, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) served as control. The 1-kb marker indicated an appropriate size for the amplified products. HIN-1 expression varied among cell lines. The presence of methylation of HIN-1 corresponds directly to the loss of expression of the genes in each cell line.