Flax-seed extracts with phytoestrogenic effects on a hormone receptor-positive tumour cell line.
The higher soy intake in the Asian population compared to Europeans is believed to be an essential factor for the lower incidence of hormone-dependent tumours in Asia. It has already been shown that soya beans, with their ingredients genistein and daidzein from the isoflavonoid group, have protective effects on hormone-caused diseases. Lignans are another, less investigated, group of phytoestrogens. The aim of this study was to investigate the effects of flax-seed, which is typically found in Northern European diets, on the proliferation and hormone production of an estrogen receptor (ER)-positive trophoblast tumour cell line.


METHODS
Trophoblast tumour cells of the cell line Jeg3 were incubated with 2 different concentrations of the isolated crude extract of flax-seed and 7 chemically partitioned extract fractions. Untreated cells were used as controls. After 48 h of stimulation, cell proliferation was measured using the BrdU method. The concentrations of hCG and progesterone produced by the trophoblast tumour cells were measured 48 h after stimulation. Extract fractions with antiproliferative effects in the BrdU- test were analysed by HPLC-MS.


RESULTS
Our study showed an inhibitory influence of some of the isolated flax-seed fractions on the Jeg3 tumour cells. Proliferation of the Jeg3 cells was decreased by flax-seed fractions I, V, VI and VII in a dose-dependent manner. Inhibition of hCG production by flax-seed extracts III, V, VI and VII was also dose-dependent. Extract fractions V and VI decreased the production of progesterone by 58% to 86%. Some extract fractions showed a stimulating effect on hormone production and cell proliferation. HPLC-MS analysis showed the presence of matairesinol and biochanin A in flax-seed fraction VI.


CONCLUSIONS
Flax-seed seems to have similar inhibitory effects to soya on hormone production and proliferation of hormone-sensitive tumour cells. Our results showed a dose-dependent inhibition by isolated flax-seed extracts on the Jeg3 cell line. Matairesinol and biochanin A seem to be useful candidates for extended tests on other tumour cell lines and normal tissues to evaluate the potential benefit of a lignan-containing therapy in hormone-dependent diseases.
Waldschläger
J
J
Department of Obstetrics and Gynaecology, University of Rostock, Germany. juliane.waldschlaeger@kliniksued-rostock.de
Bergemann
C
C
Ruth
W
W
Effmert
U
U
Jeschke
U
U
Richter
D U
DU
Kragl
U
U
Piechulla
B
B
Briese
V
V
D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D002822:Choriocarcinoma / Q000378:metabolism* / Q000473:pathology; D002851:Chromatography, High Pressure Liquid; D019597:Flax / Q000737:chemistry*; D006801:Humans; D007150:Immunohistochemistry; D013058:Mass Spectrometry; D048789:Phytoestrogens / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D011960:Receptors, Estrogen / Q000378:metabolism*
D048789:Phytoestrogens; D010936:Plant Extracts; D011960:Receptors, Estrogen