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a generic term for any of the estrus-producing compounds (female sex hormones), including estradiol, estriol, and estrone. Called also estrogenic hormone. In humans, the estrogens are formed in the ovary, adrenal cortex, testis, and fetoplacental unit, and are responsible for female secondary sex characteristic development, and during the menstrual cycle, act on the female genitalia to produce an environment suitable for fertilization, implantation, and nutrition of the early embryo. Uses for estrogens include oral contraceptives, hormone replacement therapy, advanced prostate or postmenopausal breast carcinoma treatment, and osteoporosis prophylaxis.
conjugated e's a mixture of the sodium salts of the sulfate esters of estrone and equilin; therapeutic uses are similar to those of other estrogens; administered orally, intravenously, intramuscularly, or intravaginally.
esterified e's a mixture of esters of estrogenic substances, principally estrone, having therapeutic uses similar to those of other estrogens.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Any substance capable of preventing full expression of the biologic effects of estrogenic hormones on responsive tissues, either by producing antagonistic effects on the target tissue, as androgens and progestogens do, or by competing with estrogens at estrogen receptors at the cellular level (for example, tamoxifen).
Synonym(s): estrogen antagonist
Farlex Partner Medical Dictionary © Farlex 2012


Any substance capable of preventing full expression of the biologic effects of estrogenic hormones on responsive tissues.
Synonym(s): antioestrogen.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Multi variable analysis revealed that low adherence was linked to reduction in DFS: the risk of recurrence was 35-36% greater when compared to patients who completed the 5-year course of antioestrogen therapy.
The usual finding is a negative discordance of PR receptors where the loss of these reduces the response to antioestrogen therapy and is coupled with an increase in the proliferative marker Ki67.
For women with ER positive cancers the benefits of antioestrogen therapy can only be achieved by compliance with the drugs prescribed.
Tamoxifen has been found as an antioestrogen to significantly reduce the risk of recurrent or contralateral breast cancer.
Enhanced epidermal growth factor receptor signaling in MCF7 breast cancer cells after long-term culture in the presence of the pure antioestrogen ICI 182,780 (Faslodex).
Constitutive MEK/MAPK activation leads to p27(Kip1) deregulation and antioestrogen resistance in human breast cancer cells.
Nonendocrine pathways and endocrine resistance: observations with antioestrogens and signal transduction inhibitors in combination.
Effects of a non-steroidal pure antioestrogen, ZM 189,154, on oestrogen target organs of the rat including bones.
Effects of a non-steroidal pure antioestrogen, ZM189,154, on oestrogen target organs of the rat including bones.
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds as antioestrogens: characterization and mechanism of action.
Determination of urinary lignans and phytoestrogen metabolites, potential antioestrogens and anticarcinogens, in urine of women on various habitual diets.
Clodronate improves bone mineral density in post-menopausal breast cancer patients treated with adjuvant antioestrogens. Br J Cancer 1997;75:602-5.