Polymorphisms of human estrogen receptor (ER) gene alpha and beta in prostate cancer PC-EW and PC-OR cell lines.

BACKGROUND Prostate cancer is the second leading cause of death among men in Western countries. Genetic alterations of the estrogen receptor gene are known to be indicative of a higher risk of this disease. The estrogen receptor gene is found as two subtypes, alpha and beta. In this study the estrogen receptor alpha and beta genes were tested in 2 human prostate cancer cell lines: the hormone-sensitive PC-EW and the hormone-independent PC-OR. MATERIALS AND METHODS Genomic DNA was isolated from 2 cell lines from metastatic prostate adenocarcinoma in hetero-transplanted male athymic nude (nu/nu) Balb/c mice. Mutation screening was performed by sequencing of exons 1-8 and intron 1 of the human estrogen receptor gene alpha, and exons 1-9 of estrogen receptor gene beta. RESULTS No point mutations were detected in the ER gene subtypes of either cell line. Polymorphisms were found of ER-alpha in exon 1, intron 1, exon 3, 4, 5, intron 6 and exon 8 and of ER-beta in intron 2 and exon 9. CONCLUSION Point mutations of ER-alpha and -beta are not necessary for metastatic prostate cancer, alterations in different areas of the ER genes are more often found. These polymorphisms are a part of many genetic influences that accumulate to contribute to men's overall risk for developing prostate cancer.