Identification of CpG Sites of SERPINA5 Promoter with Opposite Methylation Patterns in Benign and Malignant Prostate Cells.

BACKGROUND/AIM: To date there has been no investigation into the epigenetic regulation of the serine protease inhibitor SERPINA5 in prostate cancer, where lack of this gene was considered to facilitate invasive growth patterns. MATERIALS AND METHODS: Methylation degrees of eight CpG sites of SERPINA5 were analyzed in normal and malignant prostate cells using nucleotide sequencing, methylation-specific high resolution melting and digital droplet PCR techniques. RESULTS: The methylation degree of five CpG sites significantly correlated with lower SERPINA5 expression levels. In contrast, two CpG sites (at -19 bp and -14 bp from the transcription start site) were hypermethylated in normal epithelial prostate cells, benign hyperplasic cells and low-invasive malignant LNCaP cells, whereas in aggressive DU-145 and PC-3 cell lines, these sites were essentially unmethylated. CONCLUSION: Novel methylation patterns of two distinct CpG sites of the SERPINA5 promoter may be useful for differentiating benign from malignant prostate disease.