Background/Aim: DNA methylation is a common epigenetic change in cancer. However, microRNA (miRNA) regulation by epigenetic alteration, especially CpG island hypermethylation, remains poorly understood in esophageal squamous cell carcinoma (ESCC). Materials and Methods: miRNAs which were up-regulated after de-methylation with 5- aza-2'-deoxycytidine (5-AZA) were analyzed using the Human miFinder 384HC miScript miRNA PCR Array. The DNA methylation level was evaluated by bisulfite-pyrosequencing assay. Results: In two of the cell lines, 20 miRNAs, including miR-145-5p, were found to be up-regulated by more than three-fold after 5-AZA treatment. The miRNA-145 promoter was significantly more hypermethylated in the cancer tissues than in matched normal adjacent esophageal epithelial mucosa (p=0.0042; paired t-test). Moreover, the miRNA-145- 5p expression levels were significantly lower in cancerous tissues (p=0.0024). Conclusion: miRNA-145 expression in ESCC seems to be regulated by hypermethylation of the miRNA-145 promoter region.
|Number of pages||8|
|Publication status||Published - Sept 1 2015|
All Science Journal Classification (ASJC) codes
- Cancer Research