Membrane-initiated effects of Serelys® on proliferation and apoptosis of human breast cancer cells.

Herbal extracts used for the alleviation of postmenopausal symptoms might have a lower risk of breast cancer development than hormone therapy. Serelys® is a product composed of purified pollen cytoplasm extracts. Recent experimental data revealed that estrogens might trigger a further proliferative effect on breast cancer cells via the progesterone receptor membrane component-1 (PGRMC1) in addition to the proliferative effect via intracellularly located receptors. MCF-7 and T47D cells were stably transfected with PGRMC1. Different concentrations of the extract alone and in combination with fixed concentrations of estradiol or a growth factor mixture were tested. Proliferation of treated cells was determined by the 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl-tetrazolium bromide (MTT)-test and apoptosis was determined using a Cell Death Detection ELISA kit (CDD). Serelys® was neutral in the cell lines transfected or not transfected with PGRMC1. It was also neutral in combination with estradiol or growth factors in terms of cell proliferation and cell apoptosis. Thus in contrast to hormone therapy Serelys® appears to trigger no further breast cancer risk when applied in the post menopause to women, who do or do not overexpress PGRMC1. Overall Serelys® may be an effective alternative for alleviating postmenopausal symptoms without increasing breast cancer risk.