Characterisation of oestrogenic activity of ginsenosides in MCF-7 cells using a customised DNA microarray

We studied oestrogenic activity of components of ginseng: ginsenosides F1, Rb1, Rg1 and Rh1. These ginsenosides dose-dependently stimulated the proliferation and oestrogen-responsive luciferase activity of human breast cancer MCF-7 cells, with a maximal level at 100 μM. Both proliferation and luciferase activities induced by ginsenosides were blocked by ICI 182,780, an oestrogen receptor antagonist. We further examined expression profiles of oestrogen-responsive genes after the treatment with these ginsenosides using a cDNA microarray containing a set of 120 oestrogen-responsive genes, which are related to enzymes, signalling, proliferation, transcription and transport. Similar expression profiles were obtained between the cells treated with 17β-oestradiol (E2) and ginsenosides F1or Rb1, while many genes showed unique responses after the treatment with E2 and ginsenosides Rg1 and Rh1. Statistically significant correlations, expressed as correlation coefficients (r-values), were observed for the expression profiles between E2 and either of ginsenosides F1 (r = 0.655, p < 1%), Rb1 (r = 0.378, p < 1%), Rg1 (r = 0.213, p < 5%), or Rh1 (r = 0.218, p < 5%). These results suggest that these ginsenosides have various degrees of oestrogenic activity and are functionally similar in part to E2.