Effects of phytoestrogen extracts isolated from pumpkin seeds on estradiol production and ER/PR expression in breast cancer and trophoblast tumor cells.

Phytoestrogens have a controversial effect on hormone-dependent tumours. Herein, we investigated the effect of the pumpkin seed extract (PSE) on estradiol production and estrogen receptor (ER)-α/ER-ß/progesterone receptor (PR) status on MCF7, Jeg3, and BeWo cells. The PSE was prepared and analyzed by mass spectrometry. MCF7, Jeg3, and BeWo cells were incubated with various concentrations of PSE. Untreated cells served as controls. Supernatants were tested for estradiol production with an ELISA method. Furthermore, the effect of the PSE on ER-α/ER-ß/PR expression was assessed by immunocytochemistry. The PSE was found to contain both lignans and flavones. Estradiol production was elevated in MCF7, BeWo, and Jeg3 cells in a concentration-dependent manner. In MCF7 cells, a significant ER-α downregulation and a significant PR upregulation were observed. The above results after properly designed animal studies could highlight a potential role of pumpkin seed's lignans in breast cancer prevention and/or treatment.

Antiproliferative activity of lignans against the breast carcinoma cell lines MCF 7 and BT 20.

PURPOSE: Phytoestrogens are plant-derived, non-steroidal phytochemicals with anticarcinogenic potential. The major structural classes are the isoflavones and lignans. The aim of this study was to compare the effect of the plant-derived lignans secoisolariciresinol and matairesinol with the human lignans enterodiol and enterolactone as well as with 17ß estradiol and tamoxifen on cell proliferation of breast carcinoma cell lines. METHODS: The influence of the lignans, 17ß estradiol and tamoxifen on cell proliferation was determined using the BrdU test in MCF 7 and BT 20 cell lines. RESULTS: Enterodiol and enterolactone induced a stronger inhibition of cell growth in MCF 7 and BT 20 cells than secoisolariciresinol and matairesinol. The inhibition effects were less expressed in the BT 20 than in the MCF 7 cells. CONCLUSIONS: The human lignans enterodiol and enterolactone are more biologically active than their precursors secoisolariciresinol and matairesinol, and may be defined as the real drugs in cancer prevention.

Effects of elm bark extracts from Ulmus laevis on human chorion carcinoma cell lines.

PURPOSE: The potential of substances from elm bark extracts to affect cancer has been described in several studies. In this study, the anticancer effects of extracts from Ulmus laevis bark were tested in hormone-dependent gynecological tumours using human chorion carcinoma cell lines. METHODS: The molecular-chemical composition of the bark extract was analysed by pyrolysis-field ionisation mass spectrometry. The influence of the extracts was determined on cell vitality and cytotoxicity in the human chorion carcinoma cell lines Jeg3 and BeWo in comparison with primary trophoblast cells. RESULTS: The elm bark extract was mainly composed of triterpenes, phytosterols, free fatty acids and suberins with lower amounts of dilignols and lipids. The elm bark extract significantly inhibited the vitality of Jeg3 and BeWo cells but increased the vitality of primary trophoblast cells. CONCLUSIONS: Substances extracted from elm bark might have beneficial effects for the prevention of hormone-dependent tumours.

Inhibitory effects of bark extracts from Ulmus laevis on endometrial carcinoma: an in-vitro study.

Anti-inflammatory effects of elm tree have been shown in several studies. Besides this, protective effects of components of elm bark on damaged tissue have also been described. This study was carried out to investigate the antitumour potential of an ethanolic extract isolated from Ulmus laevis in the hormone-dependent endometrial carcinoma cell line RL95-2. A range of 2.5-500 microg/ml of elm bark extract was used as standard concentrations. The molecular-chemical composition of the bark extract was analysed by pyrolysis-field ionization mass spectrometry. The influence of the bark extracts was determined on cell vitality [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide test], cell proliferation (5-bromo-2-deoxyuridine test) and cytotoxicity (lactate dehydrogenase test) in the human endometrial carcinoma cell line RL 95-2. By pyrolysis-field ionization mass spectrometry, the main substance classes of the extract as a composition of sterols/triterpenes, free fatty acids and a group of phenols, lignin monomers and flavonoids was identified. Our study showed a significant inhibition of cell vitality and proliferation measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide test up to 5 microg/ml extract and up to 100 microg/ml according to the 5-bromo-2-deoxyuridine test. Concentrations of 500 microg/ml induced a significant inhibition of cell vitality up to 80% and cell proliferation up to 81.5%. A significant cytotoxity was not observed. The results lead to the assumption that the bark extract from Ulmus laevis has antiproliferation and anticancer potential in hormone-dependent endometrial carcinoma cells.