Properties and mode of action of pure antioestrogens in breast cancer in vitro

Experimental studies on oestrogen sensitive and resistant human breast cancer cells in culture have revealed that pure antioestrogens promote growth arrest and reduce the expression of oestrogen regulated genes. Their actions are superior to both tamoxifen-like antioestrogens and oestrogen withdrawal, a feature resultant from their unique capacity to inhibit steroid hormone and growth factor interactions. This property may be aided by their ability to deplete cellular levels of the oestrogen receptor