OBJECTIVES: The effect of androgen deprivation therapy on the expression of androgen receptors (AR) and the proliferation-associated MIB-1 antigen in prostatic intraepithelial neoplasia (PIN) was investigated. METHODS: Immunohistochemistry was performed on tissue sections of prostatectomy specimens of patients with prostate cancer who either were not treated prior to surgery or received androgen blockade therapy for 3 months. Immunohistochemistry on slides, selected for the presence of PIN was performed with an AR-specific monoclonal antibody and MIB-1 using a microwave antigen-retrieval method. RESULTS: AR expression was present in a majority of cells in PIN of both untreated and treated prostatectomy specimens. In addition, a proportion of normal prostatic glandular cells retained AR expression. The basal cells in both untreated and treated PIN did not express AR. MIB-1-positive cells were identified in PIN of untreated and treated cases. CONCLUSIONS: PIN lesions that persist after 3 months of androgen deprivation therapy continue to express AR and may therefore retain the potential to expand after cessation of this therapy.
OBJECTIVES: The effect of androgen deprivation therapy on the expression of androgen receptors (AR) and the proliferation-associated MIB-1 antigen in prostatic intraepithelial neoplasia (PIN) was investigated. METHODS: Immunohistochemistry was performed on tissue sections of prostatectomy specimens of patients with prostate cancer who either were not treated prior to surgery or received androgen blockade therapy for 3 months. Immunohistochemistry on slides, selected for the presence of PIN was performed with an AR-specific monoclonal antibody and MIB-1 using a microwave antigen-retrieval method. RESULTS: AR expression was present in a majority of cells in PIN of both untreated and treated prostatectomy specimens. In addition, a proportion of normal prostatic glandular cells retained AR expression. The basal cells in both untreated and treated PIN did not express AR. MIB-1-positive cells were identified in PIN of untreated and treated cases. CONCLUSIONS: PIN lesions that persist after 3 months of androgen deprivation therapy continue to express AR and may therefore retain the potential to expand after cessation of this therapy.