Bicalutamide dose-dependently inhibits proliferation in human prostatic carcinoma cell lines and primary cultures

Objective: Androgen antagonists inhibit prostatic cell proliferation in normal and pathological conditions and are useful antitumor agents in prostatic carcinoma (PCa). Bicalutamide (BCLT) is a well-known non-steroidal antiandrogenic agent able to interfere with androgen receptor (AR). We tested the efficacy of BCLT in inhibiting proliferation of human PCa cell lines and of primary cultures from biopsies of PCa patients. Materials and Methods: Human prostatic carcinoma cell lines (PC3, DU145, LNCaP ALVA 31 and ND1) and short-term primary tissue cultures from PCa patients were treated with BCLT. Cell proliferation and orange acridine and ethidium bromide fluorescence staining studies were performed. Results: BCLT was able to inhibit, significantly and dosedependently, cell proliferation in AR-positive human PCa cell lines and in 10 cases of primary cultures with Gleason grades 4 to 8. Its action appears to be mainly apoptotic in AR-positive cells and cytotoxic in AR-negative cells. Conclusion: BCLT, which inhibits growth in both human PCa cell lines and PCa primary cultures from patients with medium and low-grade tumors, deserves attention as a potential widely effective antiandrogenic monotherapy in prostatic carcinoma. However, its efficacy in AR-negative cells requires further research.