Search results for "Estrogen."
showing 10 items of 529 documents
Heterocyclisch anellierte Steroide aus 2-Hydroxymethylen-canrenon
1995
A-ring annulated heterocycles, the isoxazole 6, the pyrazoles 8 and the pyrimidines 9 are prepared starting from 2-hydroxymethylene canrenone 1. Binding studies were carried out with the compounds 1 and 6-8 using estrogen, progesterone, androgen, gluco- and mineralocorticoid receptors as well as the serum proteins SHBG and CBG: the substances were inactive on the receptor level. 1, 7 and 8a show weak binding affinity to CBG.
Adjuvant anastrozole versus exemestane versus letrozole, upfront or after 2 years of tamoxifen, in endocrine-sensitive breast cancer (FATA-GIM3): a r…
2018
Background: Uncertainty exists about the optimal schedule of adjuvant treatment of breast cancer with aromatase inhibitors and, to our knowledge, no trial has directly compared the three aromatase inhibitors anastrozole, exemestane, and letrozole. We investigated the schedule and type of aromatase inhibitors to be used as adjuvant treatment for hormone receptor-positive early breast cancer. Methods: FATA-GIM3 is a multicentre, open-label, randomised, phase 3 trial of six different treatments in postmenopausal women with hormone receptor-positive early breast cancer. Eligible patients had histologically confirmed invasive hormone receptor-positive breast cancer that had been completely remov…
Molecular Basis for Endocrine Disruption by Pesticides Targeting Aromatase and Estrogen Receptor
2020
The intensive use of pesticides has led to their increasing presence in water, soil, and agricultural products. Mounting evidence indicates that some pesticides may be endocrine disrupting chemicals (EDCs), being therefore harmful for the human health and the environment. In this study, three pesticides, glyphosate, thiacloprid, and imidacloprid, were tested for their ability to interfere with estrogen biosynthesis and/or signaling, to evaluate their potential action as EDCs. Among the tested compounds, only glyphosate inhibited aromatase activity (up to 30%) via a non-competitive inhibition or a mixed inhibition mechanism depending on the concentration applied. Then, the ability of the thr…
Dietary exposure in utero and during lactation to a mixture of genistein and an anti-androgen fungicide in a rat mammary carcinogenesis model
2015
Endocrine disruptors may play substantial roles in the high incidence of breast cancer. We previously described how early exposure to the mixture of phytoestrogen genistein (G) and the anti-androgen vinclozolin (V) affects peripubertal mammary development. This study evaluates the carcinogenic potential of exposure to V alone or associated with G from conception until weaning in Wistar rats. Dams were exposed to V, G or GV during pregnancy/lactation. At PND50 offspring were treated with DMBA[7,12-dimethylbenz(a)anthracene]. V or GV maternal exposure decreased number of DMBA-induced mammary tumors in the offspring, without significant modifications in tumor incidence, multiplicity and latenc…
Infiltrating mast cell-mediated stimulation of estrogen receptor activity in breast cancer cells promotes the luminal phenotype
2019
Abstract Tumor growth and development is determined by both cancer cell–autonomous and microenvironmental mechanisms, including the contribution of infiltrating immune cells. Because the role of mast cells (MC) in this process is poorly characterized and even controversial, we investigated their part in breast cancer. Crossing C57BL/6 MMTV-PyMT mice, which spontaneously develop mammary carcinomas, with MC-deficient C57BL/6-KitW-sh/W-sh (Wsh) mice, showed that MCs promote tumor growth and prevent the development of basal CK5-positive areas in favor of a luminal gene program. When cocultured with breast cancer cells in vitro, MCs hindered activation of cMET, a master regulator of the basal pr…
Why Women Have More Alzheimer's Disease Than Men: Gender and Mitochondrial Toxicity of Amyloid-β Peptide
2010
The main risk factors for developing Alzheimer's disease (AD) are age and gender. The incidence of the disease is higher in women than in men, and this cannot simply be attributed to the higher longevity of women versus men. Thus, there must be a specific pathogenic mechanism to explain the higher incidence of AD cases in women. In this regard, it is notable that mitochondria from young females are protected against amyloid-beta toxicity, generate less reactive oxygen species, and release less apoptogenic signals than those from males. However, all this advantage is lost in mitochondria from old females. Since estrogenic compounds protect against mitochondrial toxicity of amyloid-beta, estr…
Letter to the Editor regarding the paper by Aurilio et al., A meta-analysis of oestrogen receptor, progesterone receptor and human epidermal growth f…
2014
Sir,We have read with great interest the article in press ofAurilio et al., A meta-analysis of oestrogen receptor, pro-gesterone receptor and human epidermal growth factorreceptor 2 discordance between primary breast cancerand metastases (http://dx.doi.org/10.1016/j.ejca.2003.10.004), which will appear in Eur J Cancer. In the paper,the Authors have performed a meta-analysis of the stud-ies published in the literature concerning the discor-dance rate in oestrogen receptor (ER), progesteronereceptor (PgR) and HER2 status between primarytumour and corresponding relapse. It is well known thata considerable controversy concerns the issue of hor-mone receptors (HRs) expression as well as HER2 sta…
Estrogen Regulates the Satellite Cell Compartment in Females
2019
SUMMARY Skeletal muscle mass, strength, and regenerative capacity decline with age, with many measures showing a greater deterioration in females around the time estrogen levels decrease at menopause. Here, we show that estrogen deficiency severely compromises the maintenance of muscle stem cells (i.e., satellite cells) as well as impairs self-renewal and differentiation into muscle fibers. Mechanistically, by hormone replacement, use of a selective estrogen-receptor modulator (bazedoxifene), and conditional estrogen receptor knockout, we implicate 17β-estradiol and satellite cell expression of estrogen receptor α and show that estrogen signaling through this receptor is necessary to preven…
Estrogenic activity of zearalenone, α-zearalenol and β-zearalenol assessed using the E-Screen assay in MCF-7 cells
2017
Mycotoxins, including zearalenone (ZEA), can occur worldwide in cereals. They can enter the food chain and cause several health disorders. ZEA and its derivatives (α-zearalenol, α-ZOL and β-zearalenol, β-ZOL) have structural analogy to estrogen, thus they can bind to estrogen receptors (ERs). In order to characterize the estrogenic activity of ZEA, α-ZOL and β-ZOL, the proliferation of ER-positive human breast cancer cells (MCF-7) exposed to these mycotoxins was measured. After exposure at levels ranging from 6.25 to 25 µM, cell proliferation was evaluated by using the E-Screen bioassay. In accordance with previous studies, our results show the estrogenic activity of ZEA, α-ZOL and β-ZOL in…
Isoflavonoid-based bone-sparing treatments exert a low activity on reproductive organs and on hepatic metabolism of estradiol in ovariectomized rats
2007
International audience; The use of soy isoflavones is a potential alternative to hormone replacement therapy in post-menopausal bone-loss prevention. Nevertheless, phytoestrogens can target other organs and may disrupt cell proliferation, or could modify endogenous steroid hormone metabolism. These mechanisms could be linked to an increased risk of developing cancer. We therefore studied the possible side effects of such treatments in an experimental model of menopause. Forty adult female Wistar rats were ovariectomized and fed with a genistein-, daidzein- or equol-supplemented diet at bone-sparing levels (10 mg/kg BW/day) for 3 months. The estrogenic effects were assessed by histological a…