IN-VITRO AND IN-VIVO STUDIES OF THE POSSIBLE CHEMOPREVENTIVE FUNCTIONS OF SOYBEAN ISOFLAVONE AND FLAVONOIDS ON BREAST CANCER

Abstract

Objectives: In this study, we assess the possible influence of soybean isoflavone (genistein) and other flavonoids (quercetin and catechin) on breast cancer chemoprevention. We design in-vitro and in-vivo experiments to analyze the effect of genistein, quercetin and catechin on cell proliferation, cell migration, and angiogenesis of breast cancer cells. Methods: In cell proliferation experiment, MCF-7 cells, SKBR-3 cells, and HUVEC cells were treated with genistein and other flavonoids (catechin and/or quercetin) for 48[Formula: see text]h to assess the influence on cell growth of normal and breast cancer cells. In cell motility test, we analyze the effect of isoflavone and flavonoids on migration ability of MCF-7 cells by 16[Formula: see text]h and SKBR-3 cells by 24[Formula: see text]h in two different concentrations (1.25[Formula: see text][Formula: see text]g/ml and 2.5[Formula: see text][Formula: see text]g/ml). In the in-vivo experiment, SKBR-3 cells mixed with PBS and catechin, respectively, were injected subcutaneously into nude mice, then we investigated the effect of catechin on cell growth by observing subcutaneous tumor size changes after 15 days. Results: The results suggest that genistein and quercetin can significantly inhibit proliferation of breast cancer cells, and their inhibitory effects are independent of estrogen receptor. In cell motility tests, all of the three phytochemicals were effective in the inhibition of cell migration on two breast cancer cell lines, except for quercetin on cell migration of SKBR-3 cell line. In the in-vitro experiment, catechin showed stimulatory effect on cell proliferation of HUVEC cell line, which may consider positive effect on angiogenesis, rather than inhibitory effect. However, in the in-vivo experiment, it showed no significant change in tumor size between the groups of with and without catechin treatment. Conclusions: According to our study, the results suggest that isoflavone and flavonoids tend to inhibit cell growth and metastasis of breast cancer cells. Our in-vivo experiment does not reach a significant result, and it may be due to lower catechin concentration. Under in-vivo environment, we should also consider the possible metabolic forms of catechin that cause different result from the in-vitro study.