antiestrogen


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estrogen

 [es´tro-jen]
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.

an·ti·es·tro·gen

(an'tē-es'trō-jen),
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

an·ti·es·tro·gen

(an'tē-es'trō-jĕn)
Any substance capable of preventing full expression of the biologic effects of estrogenic hormones on responsive tissues.
Synonym(s): antioestrogen.
References in periodicals archive ?
Our work, as well as that of others (8, 9, 11, 12), would predict that second-line AIs would not help, whereas an antiestrogen might.
The pure antiestrogen ICI 182,780 (7-[9-[4,4,5,5,5-pentafluoropentyl) sulfinyl [nonyl]-estra-1,3,5(10)-triene-3,17diol) and 17[beta]-3-benzoate (E2B) (Estr-1, 3,5 (10)trien-3, 16[alpha], 17[beta]-triol) were obtained from Sigma-Aldrich (Hamburg, Germany).
Synergistic Effect: The majority of data evaluating synergism between antiestrogen therapies and natural agents are from animal or cell studies, but they do suggest potential.
Induction of ovulation by clomiphene citrate in PCOS is another common option of treatment for PCOS but this use is restricted only to ovulation induction as clomiphene basically being an antiestrogen has nothing to do with the pathology of PCOS and it does not address the underlying abnormalities of PCOS including hyperinsulinemia and hyperandrogenism (Guzick 2007).
Tamoxifen is a synthetic nonsteroid triphenyl antiestrogen drug, structurally similar to the ethylstibestriol.
ER status is significant because it strongly predicts the efficacy of antiestrogen therapies such as tamoxifen and aromatase inhibitors.
If patients are stratified using readily defined histologic subtypes of invasive carcinoma or by histologic grade, an overall good response to antiestrogen treatment might be expected in good prognosis carcinomas and lower histologic grades of IDC, NOS.
The antiestrogen tamoxifen significantly decreased the luciferase activity at concentration of 500 nM (P<0.05) (Fig.
The sections were incubated overnight at 4[degrees]C with the following primary antibodies: anti-Androgen receptor (clone AR441, 1/50 dilution, Dako, Carpinteria, CA, USA), antiEstrogen receptor (clone 1D5, 1/50 dilution, Dako, Carpinteria, CA, USA) and anti-Progesterone receptor (clone PgR 636, 1/50 dilution, Dako, Carpinteria, CA, USA).
They cited research indicating that half of breast cancer patients who experience hot flushes while on antiestrogen medication become noncompliant with the regimen after 180 days.