P53, C-ERBB-2 AND THE EPIDERMAL GROWTH-FACTOR RECEPTOR IN THE BENIGN AND MALIGNANT PROSTATE

Expression of the p53, the epidermal growth factor receptor (c-erbB-1) and c-erbB-2 protein was studied in 34 men with benign prostatic hyperplasia and 29 men with locally advanced prostate cancer by means of an immuno-histochemical method. Strong staining for p53 was found in five of 29 prostate cancers (17%; mean 21% +/- 7% of malignant cells stained in the positive tumours), but no staining was found in benign prostatic hyperplasia (p < 0.05). On the other hand, the epithelium in benign glands was stained positively for c-erbB-2 in 18% (6/34) and for the epidermal growth factor receptor in 88% (30/34); whereas malignant epithelium stained strongly for c-erbB-2 in 21% (6/29) and for the epidermal growth factor receptor in only 17% (5/29). Prostate cancer was associated with a significant decrease in epidermal growth factor receptor staining (p < 0.0001) and a significant increase in p53 staining (p < 0.05). Most of the tumours were advanced and no significant relationship was observed between tumour stage and grade and expression of p53, the epidermal growth factor receptor or c-erbB-2. These findings demonstrate that altered expression of the epidermal growth factor receptor and p53 protein occurs in prostate cancer, but were not associated with other features of prognostic importance such as stage or grade.