Prostate-specific transcription factor hPSE is translated only in normal prostate epithelial cells.

We recently cloned a novel transcription factor gene, hPSE, which belongs to the Ets gene family. hPSE mRNA was expressed specifically in prostate glandular epithelial cells and also in the human prostate carcinoma cell lines PC-3 and LNCaP. On the other hand, on immunoblot analysis with anti-hPSE antiserum, hPSE protein was detected only in human prostate tissue samples and not in PC-3 or LNCaP culture cells. Immunohistochemistry and in situ hybridization analysis revealed that hPSE protein was translated in normal prostate glandular epithelial cells, but not in carcinoma cells with hPSE transcripts. These findings suggest that expression of hPSE is regulated translationally in prostate epithelial cells and that hPSE protein is a candidate for a marker distinguishing normal cells from cancer cells in the prostate. It appeared that the 5'- and 3'-untranslated regions of hPSE transcripts might be necessary for translational control of hPSE, on the basis of results of transfection analysis in non-prostate lineage cells (HEK-293) using some deletion mutants of hPSE cDNA.