Genistein is one of the most abundant isoflavones in soy and is one of several known isoflavones. Isoflavones compounds, such as genistein and daidzein, are found in a number of plants, but soybeans and soy products like tofu and textured vegetable protein are the primary food source. Because of its similar structure to that of human estrogen it is also called a phytoestrogen. Genistein is a natural bioactive compound derived from legumes and has drawn because of its potentially beneficial effects on some human degenerative diseases. It has a weak estrogenic effect and is a well-known non-specific tyrosine kinase inhibitor at pharmacological doses.
Genistein is a soy-derived isoflavone and phytoestrogen with antineoplastic activity. Genistein binds to and inhibits protein-tyrosine kinase, thereby disrupting signal transduction and inducing cell differentiation. This agent also inhibits topoisomerase-II, leading to DNA fragmentation and apoptosis, and induces G2/M cell cycle arrest. Genistein exhibits antioxidant, antiangiogenic, and immunosuppressive activities. In adult animals, dietary genistein has chemopreventive effects on breast, prostate, and other endocrine-dependent tumors.