Table 1.
Estrogen metabolism by MCF-7 cells in the presence of genistein and daidzein.
| Inhibitor | E2 (fmol/106 cells/h) | E1-S (fmol/106 cells/h) | E2-S (fmol/106 cells/h) | E2-G (fmol/106 cells/h) |
|---|---|---|---|---|
| Control | 233.1 ± 6.9 | 13.5 ± 2.1 | 9.15 ± 1.21 | 2.76 ± 0.37 |
| 1 μM genistein | 242.1 ± 16.7 | 10.2 ± 1.8 | 5.90 ± 0.76∗ | 2.12 ± 0.34∗ |
| 5 μM genistein | 264.0 ± 8.8∗ | 2.26 ± 0.27∗ | 1.12 ± 0.37∗ | 1.41 ± 0.33∗ |
| 10 μM genistein | 277.2 ± 18.2∗ | 1.27 ± 0.22∗ | 0.54 ± 0.05∗ | 1.06 ± 0.10∗ |
| 1 μM daidzein | 244.2 ± 9.0 | 8.15 ± 1.26∗ | 5.91 ± 1.27∗ | 2.39 ± 0.27 |
| 5 μM daidzein | 260.7 ± 19.2∗ | 3.11 ± 0.34∗ | 1.27 ± 0.34∗ | 1.94 ± 0.30∗ |
| 10 μM daidzein | 275.4 ± 5.9∗ | 2.00 ± 0.30∗ | 0.69 ± 0.16∗ | 1.26 ± 0.15∗ |
Cells were incubated with increasing concentrations of the soy isoflavones genistein and daidzein and 100 nM E1 as hormone precursor for 48 h. All data represent the means ± SD of four independent biological replicates. Values in bold and marked with an asterisk (∗) are significantly different in comparison to the control values (P < 0.05).