A specific site on the surface of a cell that binds to oestrogen; the binding triggers responses of the cell to the hormone (see receptor). Oestrogen receptors occur on all target cells normally responsive to oestrogen (e.g. in the uterus) and are also found on some cancer cells, particularly in breast cancer. Oestrogen-receptor-positive cancer cells rely on oestrogen to grow and are therefore susceptible to anti-oestrogen therapy, which prevents oestrogen from binding to these receptors. This type of cancer tends to have a better prognosis than oestrogen-receptor-negative breast cancer.
Subjects: Medicine and Health.