Objective: To assess a range of phyto-oestrogens as moderators of growth and metabolism in several prostate cell lines.
Materials and methods: Four prostate cell lines (PNT-1/A, PNT-2, PC-3 and DU145) were challenged with different doses of five phyto-oestrogens (biochanin A, daidzein, genistein, genistin and nordihydroguaiaretic acid) over 3 days in culture. Cell proliferation was assessed by incorporation of 5-bromo-2'-deoxyuridine (BrdU) and metabolic activity by cleavage of a tetrazolium salt (XTT).
Results: Growth and metabolism were inhibited with all compounds and cell lines (e.g. the dose for 50% inhibition of proliferation of PC-3 cells by genistein was 38 micromol/L); differences in the patterns of results suggested that different mechanisms operated, but there was no evidence for any synergistic activity on the inhibition of cell proliferation.
Conclusion: These results offer further support for the hypothesized role of phyto-oestrogens as dietary protectors against prostatic cancer.