Abstract: Quercetin is one of flavones in phytoestrogen .Recently ,there have many researches about
quercetin, and most of them are related with estrogen correlative diseases,such as breast cancer , osteoporosis
and prostate cancer, et al. In these diseases, there may have many effects, including promoting cell apoptosis ,
controlling osteoclasts differentiation,regulation estrogen metabolism in vivo and effecting tumor cell growth
progression ,involving adhesion ,invasion and angiopoiesis .Comparing with other flavones ,quercetin has its
own distinct character. Many mechanisms may explain quercetin pharmacologic actions, mainly to sum up for
two aspests: 淤Expression of antioxidation: inducing cell apoptosis and regulating estrogen metabolism. 于
Regulation of estrogens: as a estrogen receptor (ER) modulator,quercetin restrains tumor cell growth by
influencing down鄄stream substrate of ER and impacting signal pathway

Key words: QUERCETIN, Estrogens, Receptors, estrogen, Antioxidants