Background: Worldwide among men, prostate cancer ranks third in cancer occurrence and sixth in cancer mortality. A number of 1, 4-naphthoquinone derivatives have been identified that possess significant pharmacological effects associated with antitumor activities. In this study, the in vitro effects of N-(3-chloro-1,4-dioxo 1,4-dihydro-naphthalen-2-yl)-benzamide (NCDDNB) were evaluated on androgen-dependent (CWR-22) and androgen-independent (PC-3, DU-145) human prostate cancer cell lines, and on a normal bone marrow cell line (HS-5). Specifically, the in vitro activity of this compound on cell cycle regulation and apoptosis was evaluated.
Materials and methods: Established methods of cell viability, cell cycle, Western blot and apoptosis were used.
Results: The effect of NCDDNB on CWR-22, PC-3, DU-145 and HS-5 cells revealed significant anti-tumor activities with IC(50)s, of 2.5, 2.5, 6.5, and 25 muM respectively. The results of cell cycle analysis showed that NCDDNB arrested PC-3, DU-145, and CWR-22 cells in the G(1)-phase of the cell cycle. The compound showed no effect on the cell cycle progression in the HS-5 bone marrow cell line. These findings were further validated using Western blot analysis. NCDDNB showed the greatest amount of apoptosis in the androgen-independent PC-3 cells in a time-dependent manner with the apoptotic apex at day 5 of treatment. Furthermore, NCDDNB induced-apoptosis in DU-145 and CWR-22 cells peaked at day 3 of treatment.
Conclusion: Although the mechanism of action of this compound has not been completely elucidated, the effect on the cell cycle and the induction of apoptosis in different prostate cancer cell lines prompted us to carry out a more in-depth preclinical evaluation. This study suggests that NCDDNB may have an impact on treatment of prostate cancer while protecting the bone marrow.