Methylation-mediated silencing of genes is not altered by selenium treatment of prostate cancer cells

Background: The role of selenium in reducing the risk of multiple cancers has been described in the literature. Although reports have described the antiproliferative and proapoptotic function of selenium by up-regulation of genes in these pathways, information is lacking on the target mechanisms of selenium on specific genes. This study examines whether selenium treatment alters the methylation status of epigenetically silenced genes in prostate cancer cells. Materials and Methods: Methylation of glutathione sulfotransferase pi (GSTP1) and Ras associated family 1A (RASSF1A) genes was studied using methylation sensitive PCR (MS-PCR). Gene expression was studied using Reverse Transcriptase PCR and Western Blotting. Results and Conclusion: Treatment of prostate cancer cells with selenium did not alter the expression of genes that were silenced by DNA methylation. Furthermore, the methylation status of these genes remained unaltered after treatment with seleno-DL-methionine.