Caspase 3 expression in benign prostatic hyperplasia and prostate carcinoma

BACKGROUND. Apoptotic resistance to androgen ablation represents a signific ant problem in the treatment of prostate cancer. Over expression of antiapo ptotic proteins such as Bcl-2 and mutations in p53 contribute to this resis tance. The caspase family of proteases are central executioners of the cell death pathway. They are expressed in normal prostate secretory epithelial cells. Altered expression may represent an additional component leading to cell resistance. The aim of this study was to determine by immunohistochemi stry caspase 3 expression in benign prostatic hyperplasia and prostate canc ers. METHODS. Twenty-two patients with histologically determined prostate cancer and benign prostatic hyperplasia (BPH) were investigated. All specimens we re obtained from patients undergoing surgical resection of the prostate. Im munohistochemical analysis was performed on formalin fixed paraffin embedde d sections to assess caspase 3 expression. RESULTS. Caspase 3 was expressed in 18/22 (81.1%) samples, with high expres sion in BPH which demonstrated staining in both basal and secretory epithel ial cells. Increasing grades of prostatic cancer showed a significant loss of expression in secretory epithelial layers and little staining in epithel ial cells in high-grade prostatic carcinoma. CONCLUSIONS. Altered caspase 3 expression may represent an additional mecha nism of apoptotic resistance to androgen ablation. Prostate 47:183-188, 200 1. (C) 2001 Wiley-Liss, Inc.