Estrogen Receptor-dependent Pathway Research Articles

GPR39-mediated ERK1/2 signaling reduces permethrin-induced proliferation of estrogen receptor α-negative cells

Certain insecticides are known to have estrogenic effects by activating estrogen receptors through genomic transcription. This has led researchers to associate specific insecticide use with an increased breast cancer risk. However, it is unclear if estrogen receptor-dependent pathways are the only way in which these compounds induce carcinogenic effects. The objective of this study was to determine the impact of the pyrethroid insecticide permethrin on the growth of estrogen receptor negative breast cancer cells MDA-MB-231. Using tandem mass spectrometric techniques, the effect of permethrin on cellular protein expression was investigated, and gene ontology and pathway function enrichment analyses were performed on the deregulated proteins. Finally, molecular docking simulations of permethrin with the candidate target protein was performed and the functionality of the protein was confirmed through gene knockdown experiments. Our findings demonstrate that exposure to 10–40 μM permethrin for 48 h enhanced cell proliferation and cell cycle progression in MDA-MB-231. We observed deregulated expression in 83 upregulated proteins and 34 downregulated proteins due to permethrin exposure. These deregulated proteins are primarily linked to transmembrane signaling and chemical carcinogenesis. Molecular docking simulations revealed that the overexpressed transmembrane signaling protein, G protein-coupled receptor 39 (GPR39), has the potential to bind to permethrin. Knockdown of GPR39 partially impeded permethrin-induced cellular proliferation and altered the expression of proliferation marker protein PCNA and cell cycle-associated protein cyclin D1 via the ERK1/2 signaling pathway. These findings offer novel evidence for permethrin as an environmental breast cancer risk factor, displaying its potential to impact breast cancer cell proliferation via an estrogen receptor-independent pathway.

Bisphenol A-Induced Endocrine Dysfunction and its Associated Metabolic Disorders.

Bisphenol A (BPA) is an endocrine-disrupting chemical widely present in many consumer goods that poses a significant threat to our health upon exposure. Humans are exposed to BPA, which directly or indirectly causes endocrine dysfunctions that lead to metabolic disorders like obesity, fatty liver diseases, insulin resistance, polycystic ovarian syndrome, and other endocrine- related imbalances. The duration, quantity, and period of exposure to BPA, especially during the critical stage of development, determine its impact on reproductive and non-reproductive health. Because of its endocrine-disrupting effects, the European Chemical Agency has added BPA to the candidate list of chemicals of very serious concern. Due to its estrogenic properties and structural similarities with thyroid hormones, BPA disrupts the endocrine system at different levels. It interacts with estrogen receptors at the molecular level and acts as an antagonist or agonist via an estrogen receptor-dependent signaling pathway. In particular, BPA binds to G-protein coupled receptors and estrogen receptors, activating signaling pathways that influence cellular apoptosis, proliferation, differentiation, and inflammation. BPA acts as an obesogen that promotes adipogenesis and correlates with increased lipid accumulation and elevated expression of adipogenic markers. As a metabolic and endocrine disruptor, BPA impairs cellular homeostasis by increasing oxidative mediators and decreasing antioxidant enzymes, resulting in mitochondrial dysfunction. Due to its endocrine-disrupting properties, BPA exposure induces endocrine dysfunctions, causing metabolic syndrome. This review article gives recent development and novel insights into the cellular and molecular mechanisms of BPA-induced endocrine dysfunctions and their associated metabolic disorders.

Antioxidant, Anti-Inflammatory, Anti-Menopausal, and Anti-Cancer Effects of Lignans and Their Metabolites.

Since chronic inflammation can be seen in severe, long-lasting diseases such as cancer, there is a high demand for effective methods to modulate inflammatory responses. Among many therapeutic candidates, lignans, absorbed from various plant sources, represent a type of phytoestrogen classified into secoisolariciresionol (Seco), pinoresinol (Pino), matairesinol (Mat), medioresinol (Med), sesamin (Ses), syringaresinol (Syr), and lariciresinol (Lari). Lignans consumed by humans can be further modified into END or ENL by the activities of gut microbiota. Lignans are known to exert antioxidant and anti-inflammatory activities, together with activity in estrogen receptor-dependent pathways. Lignans may have therapeutic potential for postmenopausal symptoms, including cardiovascular disease, osteoporosis, and psychological disorders. Moreover, the antitumor efficacy of lignans has been demonstrated in various cancer cell lines, including hormone-dependent breast cancer and prostate cancer, as well as colorectal cancer. Interestingly, the molecular mechanisms of lignans in these diseases involve the inhibition of inflammatory signals, including the nuclear factor (NF)-κB pathway. Therefore, we summarize the recent in vitro and in vivo studies evaluating the biological effects of various lignans, focusing on their values as effective anti-inflammatory agents.

In Silico Molecular Docking and ADMET Analysis for Drug Development of Phytoestrogens Compound with Its Evaluation of Neurodegenerative Diseases

Neurodegenerative disease is one of the problems faced by postmenopausal women due to estrogen deficiency. Phytoestrogen compounds can be used as an alternative treatment for diseases caused by estrogen deficiency by binding to their receptors through the estrogen receptor (ER) dependent pathway. With in silico studies, this study aims to predict how phytoestrogen compounds will stop neurons from dying by using the dependent ER pathway. Genistein, daidzein, glycitein, formononetin, biochanin A, equol, pinoresinol, 4-methoxypinoresinol, eudesmin, α-amyrin, and β-amyrin compounds were prepared with ChemDraw Ultra 12.0. Then their pharmacokinetic and pharmacodynamic properties were examined using SwissADME. Geometry optimization of the compound was performed using Avogadro 1.0.1, and molecular docking of the compound to the ERα (1A52) and ERβ (5TOA) receptors was performed using AutoDock vina (PyRx 0.8). The interaction visualization stage was carried out with Biovia Discover Studio 2021, while the toxicity values of the compounds were analyzed using pkCSM and ProTox II. The results showed that the equol compound met the pharmacokinetic, pharmacodynamic, toxicity criteria, and had similarities with the native ligand 17β-estradiol. Equol compound inhibits neurodegeneration via an ER-dependent pathway by binding to ERα (1A52) and ERβ (5TOA) receptors.

CRABP2 involvement in a mechanism of Golgi stress and tumor dry matter in non-small cell lung cancer cells via ER dependent Hippo pathway.

The paper aimed to explore the mechanism of cellular retinoic acid binding protein 2 (CRABP2) involvement in Golgi stress and tumor dryness in non-small cell lung cancer (NSCLC) cells through the estrogen receptor (ER) dependent Hippo pathway. Human NSCLC cell line A549 was purchased from ATCC andcultured in RPMI-1640 with 10% FBS. Attractene reagent was used for plasmid transfection. ER (sh) RNA was designed using RNAi Designer. Seventy-six hours after infection, stable cells were obtained after treated with puromycin for 3 weeks. ER silencing cells (with inhibited ER expression) were compared to the control cells (normal cultured NSCLC cell line A549, CRABP2 normal expression). CRABP2 and ER expression levels were detected by RT-PCR. MTT assay was used to detect cell proliferation, and the cell localization of ER and Golgi was observed by confocal microscopy. The invasion and metastasis of cells were analyzed by Boden chamber invasion and migration assays. Western blotting assays was used for detecting the protein expression of E-cadherin, vimentin, ZO-1 protein and epithelial-mesenchymal transition (EMT) related factors. The lower expression level of mRNA was detected in the ER-silencing group compared to the control group (P<0.05). We also found a higher proliferation level of cells, the number of invading and metastatic cells, the expression of vimentin, p-Lats1T1079, Lats1 and p-YAPS127 mRNA in the control group compared to the ER silencing group (P<0.05). And the expression level of protein kinase RNA-like endoplasmic reticulum kinase (PERK), phosphorylate eukaryotic initiation factor 2 (p-eIF2 alpha), activating transcription factor 4 (ATF4) and C/EBP-homologous protein (CHOP) in the control group was higher than that in the ER silencing group (P<0.05). Adversely, a lower expression level of E-cadherin and ZO-1 protein was found in the control group compared to the ER silencing group (P<0.05). The expression of CRABP2 in NSCLC cells was regulated by ER, and cell proliferation and invasion were regulated by the Hippo pathway. At the same time, it was found that decreased expression of CRABP2 enhanced endoplasmic reticulum/Golgi stress response.

Fenhexamid induces cancer growth and survival via estrogen receptor-dependent and PI3K-dependent pathways in breast cancer models

Fenhexamid (Fen), a fungicide used to treat gray mold of fruits and vegetables, is reported to function as an endocrine disrupting chemical via the estrogen receptors (ER), despite low-toxicity of the pesticide. In this study, we elucidated that the disrupting effects of Fen are exerted via the ER and phosphatidylinositol 3-kinase (PI3K) pathways in breast cancer models. The WST assay, live cell monitoring, cell cycle analysis, colony formation assay, apoptotic analysis by JC-1 dyeing, and Western blot analysis were applied in ER positive MCF-7 and ER negative MDA-MB-231 breast cancer cells, after exposure to 17β-estradiol (E2), Fen, ICI 182,780 (ICI; an ER antagonist) and/or Pictilisib (Pic; a PI3K inhibitor). Exposure to E2 and Fen induced the cell growth and survival ability of MCF-7 cells by increasing the S-phase cells and regulating the cell cycle-related proteins (Cyclin D1 and E1, p21 and p27). In addition, E2 and Fen treatment resulted in elevated levels of the survival-related proteins (Survivin and PCNA), and inhibited apoptosis by increasing the mitochondrial membrane potential and regulating the apoptosis-related proteins (BAX, BCL-2, and Caspase-9). These changes were reversed to the same level as the control group when exposed to their respective inhibitors, thereby indicating that the changes are exerted via the ER and PI3K pathways. In particular, co-treatment with these inhibitors induced greater inhibition than single treatment. Conversely, no alterations were observed in the ER-negative MDA-MB-231 breast cancer cells. Taken together, these results indicate that Fen promotes the growth of breast cancer cells via the ER and/or PI3K pathways, similar to the E2 mechanism. Although a relatively safe pesticide, Fen possibly exerts its influence as an endocrine disrupting chemical in ER-positive breast cancer cells via the ER and PI3K pathways.

Treatment with pesticides, fenhexamid and cyprodinil, resulted in an increase of cell cycle- and metastasis-related genes in an estrogen receptor-dependent pathway in cellular and xenografted mouse models with MCF-7 breast cancer cell

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Tumor growth of breast cancer was enhanced by fludioxonil, an antifungal agent, via estrogen receptor-dependent pathways

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Menopause and Ischemic Stroke: A Brief Review.

Ischemic stroke is one of the leading causes of morbidity and mortality worldwide. Females are protected against stroke before the onset of menopause. Menopause results in increased incidence of stroke when compared to men. The mechanisms of these differences remain to be elucidated. Considering that there is a postmenopausal phenomenon and females in general, are living longer sex hormone-dependent mechanisms have been postulated to be the primary factors responsible for the premenopausal protection from stroke and later to be responsible for the higher incidence and increased the severity of stroke after menopause. Animal studies suggest that administration of estrogen and progesterone is neuroprotective and decreases the incidence of stroke. However, the real-world outcomes of hormone replacement therapy have failed to decrease the stroke risk. Despite the multifactorial nature of sex differences in stroke, here, we briefly discuss the pathophysiology of sex steroid hormones, the molecular mechanisms of estrogen receptor-dependent signaling pathways in stroke, and the potential factors that determine the discrepant effects of hormone replacement therapy in stroke.

Effect of dioxin and 17β-estradiol on the expression of cytochrome P450 1A1 gene via an estrogen receptor dependent pathway in cellular and xenografted models.

Cytochrome P450 (CYP) 1A1 plays a major role in the metabolic activation of procarcinogens to carcinogens via aryl hydrocarbon receptor (AhR) pathway. Especially, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known as an agonist of AhR. In estrogen responsive cancers, 17β-estradiol (E2) may influence on AhR dependent expression of CYP1 family via the interaction between estrogen receptor (ER) and AhR. In the present study, the effect of E2/ER on the expression of AhR and CYP1A1 genes was investigated for MCF-7 clonal variant (MCF-7 CV) breast cancer cells expressing ER. In reverse transcription-PCR and Western blot analysis, mRNA expression level of AhR was not altered, but its protein expression level was increased by TCDD or E2. The transcriptional and translational levels of CYP1A1 appeared to be increased by TCDD or E2. The increased expression of AhR and CYP1A1 induced by E2 was restored to the control level by the co-treatment of ICI 182,780, indicating that E2 induced the protein expression levels of AhR and CYP1A1 like TCDD via an ER dependent pathway. In an in vivo xenograft mouse model transplanted with MCF-7 CV cells, the protein expression levels of AhR and CYP1A1 of tumor masses were also increased by E2 or TCDD. Taken together, these results indicate that E2 may promote AhR dependent expression of CYP1A1 via ER dependent pathway in MCF-7 CV cells expressing ER in the absence of TCDD, an agonist of AhR. The relevance of E2 and ER in CYP1A1 activation of estrogen responsive cancers may be targeted for developing more effective cancer treatments.

Cellular localization of ATBF1 protein and its functional implication in breast epithelial cells

ATBF1, a large transcription factor, was normally localized in nuclei, and its mislocalization to cytoplasm was reported in multiple cancers. However, localization of ATBF1 in breast epithelial cells and its potential functions were unknown. Here, we investigated ATBF1 localization via immunofluorescence staining in different kinds of breast epithelial cells. In MCF10A cells and normal mice mammary gland tissues, ATBF1 was mainly localized in nuclei. Knockdown of ATBF1 expression in MCF10A cells by siRNA promoted cell proliferation. Moreover, ATBF1 was co-localized with chromosome during mitosis, indicating its potential function in mitosis. In an estrogen receptor (ER)-positive breast cancer cell line (MCF7), estrogen induced ATBF1 translocation from cytoplasm to nuclei in an ER dependent pathway. In ER-negative cells (Hs578T and MDA-MB-231), ATBF1 was co-localized with GM130 in cytoplasm, indicating ATBF1 localization was associated with protein modification in golgi body. The results were beneficial for intensive investigation of ATBF1's function with different cellular localization in breast cancer.

Altered protein expression of cell cycle- and EMT-associated genes by bisphenol compounds in MCF-7 CV human breast cancer cells via estrogen receptor dependent pathway

Altered protein expression of cell cycle- and EMT-associated genes by bisphenol compounds in MCF-7 CV human breast cancer cells via estrogen receptor dependent pathway

Effects of total flavonoids from Drynariae Rhizoma prevent bone loss in vivo and in vitro

Estrogen deficiency is one of the major causes of osteoporosis in postmenopausal women. Drynariae Rhizoma is a widely used traditional Chinese medicine for the treatment of bone diseases. In this study, we investigated the therapeutic effects of the total Drynariae Rhizoma flavonoids (DRTF) on estrogen deficiency-induced bone loss using an ovariectomized rat model and osteoblast-like MC3T3-E1 cells. Our results indicated that DRTF produced osteo-protective effects on the ovariectomized rats in terms of bone loss reduction, including decreased levels of bone turnover markers, enhanced biomechanical femur strength and trabecular bone microarchitecture deterioration prevention. In vitro experiments revealed that the actions of DRTF on regulating osteoblastic activities were mediated by the estrogen receptor (ER) dependent pathway. Our data also demonstrated that DRTF inhibited osteoclastogenesis via up-regulating osteoprotegrin (OPG), as well as down-regulating receptor activator of NF–κB ligand (RANKL) expression. In conclusion, this study indicated that DRTF treatment effectively suppressed bone mass loss in an ovariectomized rat model, and in vitro evidence suggested that the effects were exerted through actions on both osteoblasts and osteoclasts.

Effect of 17[beta]-estradiol on the expression of cytochrome P450 1A1 gene via an estrogen receptor dependent pathway in cellular and xenografted ovarian cancer models

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Epithelial-mesenchymal transition and estrogen receptor-dependent pathway are linked with ovarian cancer cell growth and migration caused by cigarette smoke extracts in human ovarian cancer cells

Epithelial-mesenchymal transition and estrogen receptor-dependent pathway are linked with ovarian cancer cell growth and migration caused by cigarette smoke extracts in human ovarian cancer cells

An estrogen receptor-dependent pathway is involved in fludioxonil-induced cancer growth and metastasis linked with epithelial mesenchymal transition in cellular and xenografted ovarian cancer models

An estrogen receptor-dependent pathway is involved in fludioxonil-induced cancer growth and metastasis linked with epithelial mesenchymal transition in cellular and xenografted ovarian cancer models

Effect of benzophenone-1 and octylphenol on the regulation of epithelial-mesenchymal transition via an estrogen receptor-dependent pathway in estrogen receptor expressing ovarian cancer cells

Epithelial-mesenchymal transition (EMT) is an important process in embryonic development and cancer progression and metastasis. EMT is influenced by 17β-estradiol (E2), an endogenous estrogen. Benzophenone-1 (2,4-dihydroxybenzophenone, BP-1) and 4-tert-octylphenol (OP) are suspected endocrine disrupting chemicals (EDCs) because they can exhibit estrogenic properties. In this study, we examined whether BP-1 and OP can lead to EMT of BG-1 ovarian cancer cells expressing estrogen receptors (ERs). A wound healing assay and western blot assay were conducted to show the effect of BP-1 and OP on the migration of BG-1 cells and protein expression of EMT-related genes. BP-1 (10−6 M) and OP (10−6 M) significantly enhanced the migration capability of BG-1 cells by reducing the wounded area in the cell monolayer relative to the control, similar to E2 (10−9 M). However, when BG-1 cells were co-treated with ICI 182,780, an ER antagonist, the uncovered area was maintained at the level of the control. N-cadherin, snail, and slug were increased by BP-1 and OP while E-cadherin was reduced compared to the control. However, this effect was also restored by co-treatment with ICI 182,780. Taken together, these results indicate that BP-1 and OP, the potential EDCs, may have the ability to induce ovarian cancer metastasis via regulation of the expression of EMT markers and migration of ER-expressing BG-1 ovarian cancer cells.

Effect of estradiol and bisphenol A on human hepatoblastoma cell viability and telomerase activity.

Sex hormones from environmental and physiological sources might play a major role in the pathogenesis of hepatoblastoma in children. This study investigated the effects of estradiol and bisphenol A on the proliferation and telomerase activity of human hepatoblastoma HepG2 cells. The cells were divided into 6 treatment groups: control, bisphenol A, estradiol, anti-estrogen ICI 182,780 (hereinafter ICI), bisphenol A+ICI, and estradiol+ICI. Cell proliferation was measured based on average absorbance using the Cell Counting-8 assay. The cell cycle distribution and apoptotic index were determined by flow cytometry. Telomerase activity was detected by polymerase chain reaction and a telomeric repeat amplification protocol assay. A higher cell density was observed in bisphenol A (P<0.01) and estradiol (P<0.05) groups compared with the control group. Cell numbers in S and G2/M phases after treatment for 48 h were higher (P<0.05), while the apoptotic index was lower (P<0.05) and telomerase activities at 48 and 72 h (P<0.05) were higher in these groups than in the control group. The cell density was also higher in bisphenol A+ICI (P<0.01) and estradiol+ICI (P<0.05) groups compared with the ICI group. Furthermore, cell numbers were increased in S and G2/M phases (P<0.05), while the apoptotic index was lower (P<0.05) and telomerase activities at 48 and 72 h were higher (P<0.05) in these groups than in the ICI group. Therefore, bisphenol A and estradiol promote HepG2 cell proliferation in vitro by inhibition of apoptosis and stimulation of telomerase activity via an estrogen receptor-dependent pathway.

Ovarian cancer cell growth was induced by lambda-cyhalothrin and cypermethrin in in vitro model of ovarian cancer via an estrogen receptor-dependent pathway

Ovarian cancer cell growth was induced by lambda-cyhalothrin and cypermethrin in in vitro model of ovarian cancer via an estrogen receptor-dependent pathway

Effect of fenhexamid and cyprodinil on the expression of cell cycle- and metastasis-related genes via an estrogen receptor-dependent pathway in cellular and xenografted ovarian cancer models

Fenhexamid and cyprodinil are antifungal agents (pesticides) used for agriculture, and are present at measurable amounts in fruits and vegetables. In the current study, the effects of fenhexamid and cyprodinil on cancer cell proliferation and metastasis were examined. Additionally, the protein expression levels of cyclin D1 and cyclin E as well as cathepsin D were analyzed in BG-1 ovarian cancer cells that express estrogen receptors (ERs). The cells were cultured with 0.1% dimethyl sulfoxide (DMSO; control), 17β-estradiol (E2; 10(-9)M), and fenhexamid or cyprodinil (10(-5)-10(-7)M). Results of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that fenhexamid and cyprodinil increased BG-1 cell proliferation about 1.5 to 2 times similar to E2 (5 times) compared to the control. When the cells were co-treated with ICI 182,780 (10(-8)M), an ER antagonist, the proliferation of pesticide-treated BG-1 cells was decreased to the level of the control. A wound healing assay revealed that the pesticides reduced the disrupted area in the BG-1 cell monolayer similar to E2. Protein levels of cyclin D1 and E as well as cathepsin D were increased by fenhexamid and cyprodinil. This effect was reversed by co-treatment with ICI 182,780. In a xenograft mouse model with transplanted BG-1 cells, cyprodinil significantly increased tumor mass formation about 2 times as did E2 (6 times) compared to the vehicle (0.1% DMSO) over an 80-day period. In contrast, fenhexamid did not promote ovarian tumor formation in this mouse model. Cyprodinil also induced cell proliferation along with the expression of proliferating cell nuclear antigen (PCNA) and cathepsin D in tumor tissues similar to E2. Taken together, these results imply that fenhexamid and cyprodinil may have disruptive effects on ER-expressing cancer by altering the cell cycle- and metastasis-related gene expression via an ER-dependent pathway.