RESUMO
BACKGROUND: The effects of phenethyl isothiocyanate (PEITC), present naturally in cruciferous vegetables, on androgen-influenced growth of the prostate such as benign hyperplasia, was investigated. METHODS: Rats dosed with cyproterone acetate and testosterone, were fed at the same time with either PEITC or vehicle control. The growth of the prostates was compared to untreated rats. RESULTS: While testosterone increased the prostate mass (30%) and hyperplastic seminiferous tubules as compared to the untreated rats, PEITC feeding decreased the prostate mass and hyperplasia to roughly the levels of untreated rats (P < 0.05). PEITC negated the testosterone-mediated enhancement of the androgen receptor (AR), via down-regulating transcription factor Sp1 expression and Sp1 binding complex formation. Cell cycle progression was attenuated with decreases of cyclins, Rb, and up-regulates p27. CONCLUSIONS: PEITC modulates the testosterone-influenced growth by repressing Sp1, thus down-regulating AR and proliferation. PEITC from cruciferous vegetables may represent a regulator for hormone-dependent growth of the prostate.