Expression of estrogen receptor-B ( ER-B ) in bengin and malignant prostatic epithelial cells and its correlation with the clinico-pathological features

The role of estrogen and its receptors in the etiology and progression of prostate cancer ( PC ) is poorly understood. In normal and malignant human prostate, estrogen receptor-a is expressed only in the stroma, whereas estrogen receptor-Beta ( ER-Beta ) is present in both normal stroma and epithelium. Because loss of ER-Beta expression is associated with prostate hyperplasia in ER-Beta null mice, this study determined patterns of ERBeta expression in hyperplastic, PIN ( prostatic intraepithelial neoplasia ) and malignant human prostate and associations with tumor progression. Formalin-fixed, paraffin-embedded blocks were obtained from thirty-five patients who underwent radical prostatectomy and pelvic lymphadenectomy for prostate cancer, 15 core biopsies diagnosed as PIN and 10 TURP ( transurethral prostatic resection ) diagnosed as BPH ( benign prostatic hyperplasia ) were assessed for ER-Beta expression using immunohistochemistry. ER-Beta positivity was defined as 5% of cells demonstrating nuclear immunoreactivity. Nine ( 90% ) of the studied BPH cases showed ER-Beta positive expression where they showed 5% ER-Beta positive cells, while eight ( 53% ) of the studied 15 PIN cases were negative for ER-Beta expression. Twenty-nine ( 82.8% ) of the studied adenocarcinoma cases were negative for ERBeta expression, p