Anti-Cancer Effects Of Genistein And Its Mechanisms Of Actions

Genistein(4',5,7-trihydroxyl isoflavone) is an interesting compound, which is rich in soybean and soy foods. Investigations imply that soy intake is associated with low risk of cancer,and genistein may be one of the compounds which caused low incidence of cancer. In order to explore the possibility of developing it as a plant-derived, low toxic and effective anticancer drug, we studied the effects of genistein on cell growth, differentiation, chemical transformation, and invasion and metastasis of cancer cells. We also tried to elucidate the mechnisms underlying these anti-cancer effects of genistein. Main results could be summarized as follows:(1)Effects of genistein on the growth of cancer cells.With MTT assay, genistein was found to inhibit significantly the growth of cancer cells derived from different tissues, including human epidermal(KB), colon (HCT-8), ovary (A2780), mammary (MCF-7), and liver (Bel7402), with IC₅₀ ranged from 13.9μM to 33.8μM. As KB/V200 cells (which were derived from KB and resistant to vincristine and taxol) were concerned, genistein also retarded their growth (IC₅₀=29.2μM). Programmed cell death was observed in human leukemia NB-4 cells when they were treated with genistein. This effect was associated with suppression of bcl-2 gene expression. Genistein was also found to inhibit the activities of DNA topoisomerase II, and make significant changes in the contents of P53 and c-Myc proteins in B16-BL6 cells, which may be ascribed to its effects on cell growth and...