Effect ofβ-sitosterol on T47D Cell Proliferation and Cell Cycle and Its Mechanisms / 世界科学技术-中医药现代化

ABSTRACT

This study was aimed to observe the influence of β-sitosterol (BSS) on estrogen receptor (ER) positive the human breast cancer cell line T47D and to study its mechanisms. ER antagonist ICI182 780 was employed to observe the influence on the proliferation. Proliferations of T47D cells influenced by different concentrations of BSS were analyzed by MTT assay. Cell cycle analyses were examined by flow cytometry. The protein expression of cyclin D1 was measured by western blot analysis and cyclin D1 mRNA was quantified by real-time PCR assay. The results showed that BSS in high dose exhibited significant inhibitory effects that were partly antagonized by ICI182 780 and decreased the proliferative index on T47D cells. However, BSS in low dose obviously promoted the proliferation that was completely inhibited by ICI182 780 and increased the proliferative index on T47D cells. The mRNA and protein levels of cyclin D1 were increased in low-dose BSS. The effect was blocked by ICI182 780. It was concluded that BSS in low concentration had phytoestrogenic effect by up-regulating the expression of cyclin D1 via ER pathway.