DNA demethylase is expressed in ovarian cancers and the expression correlates with demethylation of CpG sites in the promoter region of c-erbB-2 and survivin genes.

摘要: The objectives of this study were to examine DNA demethylase (dMTase) expression in ovarian cancers and evaluate methylation CpG sites the promoter c-erbB-2 gene survivin exon 1. Forty-three epithelial 43 non-cancerous tissues studied for dMTase by RT-PCR. Genomic was extracted digested with HindIII then HpaII. site-sensitive primers constructed amplify Immunohistochemical evaluation ErbB-2 protein RT-PCR also performed. positive 88.4% but only 9.3% ovaries (P<0.001, Fisher's exact test). similarly observed both early stage (stage I+II: 17/19) advanced III+IV: 21/24) groups malignancy. It found that 78.9% dMTase-positive had 1 unmethylated, whereas 40% dMTase-negative methylated. In ovaries, these mostly methylated (90.6%) difference from cancer cases highly significant (P<0.001). showed correlation unmethylated expression. 86% six negative. Exon 83% survivin-negative cases. This is first report cancers. unmethylation suggests may be targets demethylation enzyme. up-regulation oncogenes consequence epigenetic control dMTase.