جستجوی مقالات مرتبط با کلیدواژه « estrogen receptor alpha » در نشریات گروه « پزشکی »

There are many studies which strongly suggest that the pathophysiology of Temporomandibular joint Disorder (TMD) may also be influenced by genetic conditions. The current study was aimed to evaluate the hypothesis that the polymorphism of estrogen receptor genes, estrogen receptor 1 and 2 (ESR1 and ESR2), and the gene Catechol -O-Methyl-Transferase (COMT) could be Predisposing factor for TMD.

Methods:

 In this case-control study, blood sample were taken from 100 TMD diagnosed patients based on Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and 103 healthy individuals as the control group. Tetra ARMS-PCR method was used to amplify and identify COMT rs4680, ESR1 rs1643821, and ESR2 rs1676303 gene polymorphism.

ESR1 genotype AA and GA showed significantly increase probability (OR= 4.80, OR=2.98, respectively) of TMD. ESR2 T/T homozygosity was associated with decreased risk for TMD (OR=0.41). The relationship between COMT and TMD was not statistically significant (p>00.05). The relationship between the severity of TMD and ESR1 was significant (p=0.003). According to the inheritance pattern the COMT and ESR1 gene, in the dominant pattern can be susceptible to TMD and in ESR2 gene, in the recessive pattern can be protective to TMD.

It seems that SNPs of ESR1 rs1643821 has a susceptible role and ESR2 rs1676303 has a protective role against TMD. Also, we add evidences that various genotype of COMT rs4680 were not statistically different between case and control, but allele A in the dominant inherence pattern can be susceptible to TMD.

In 1980, tamoxifen was introduced as an effective adjuvant endocrine therapy for breast cancer, resulting in a significant increase in overall survival. Nevertheless, the development of acquired resistance limited the efficacy of tamoxifen therapy. Several molecular mechanisms have been proposed to explain the probable process of tamoxifen resistance. In vitro studies have suggested that alterations in the expression of cytoplasmic growth cascades such as insulin-like growth factor receptor (IGFR) and epidermal growth factor receptor (EGFR) along with associated downstream signaling pathways such as ERK1, ERK2, and ERK6 are the main cause of resistance to tamoxifen. In this review, we investigated the role of estrogen receptor-α (ER-α), EGFR, IGFR, and their downstream signaling pathways in tamoxifen resistance. The present study attempted to find out possible culprits of tamoxifen resistance to improve treatment efficacy in breast cancer patients.

Primary ovarian insufficiency (POI) is a rare disease clinically characterized by ovarian follicles depletion or dysfunction and menopause before the age of 40 yr as the cut-off age for POI. It is a complex disease, and its etiology involves several factors. However, genetic factors have a predominant role in the susceptibility to the disease.

This study aims to investigate the polymorphisms of rs243865 in the matrix metallopeptidase 2 (MMP2) gene and rs2234693 and rs9340799 in the estrogen receptor 1 (ESR1) gene with susceptibility to POI in Iranian women under 35 yr.

This case-control study was performed on 150 women with POI and 150 healthy women who were referred to Yazd Reproductive Sciences Institute, Yazd, Iran between May-October 2020. The genotyping of ESR1 rs9340799, rs2234693, and MMP2 rs243865 polymorphism was done using tetra-amplification refractory mutation system-polymerase chain reaction. In addition, haplotype analysis and linkage disequilibrium were investigated by SNPanalyzer software.

Our study revealed the frequency of rs243865 TT, CC genotypes in the MMP2 gene and rs2234693 CC, TT; and rs9340799 GG, AA in the ESR1 gene were more prevalent in the case group compared to the control group. In addition, ESR1 rs2234693 and rs9340799 genotypes showed significant association with the development of the disease in our population. Among 4 haplotypes for 2 polymorphisms in the ESR1 gene, rs2234693T/rs9340799A haplotype was associated with conferring risk to POI.

ESR1 rs2234693 and rs9340799 polymorphism were strongly associated with our population’s POI.

Female sex hormones have a pro-inflammatory effect, which may help to minimize inflammation. Estrogen's immunoregulatory properties play a significant role in the bi-directional neuroendocrine-immune activity in females. As a result, sex hormones can play a role in men's high mortality rate from coronavirus-2019 (COVID-19). It is aimed to clarify the role of 17-estradiol (E2) in the battle against COVID-19.

Until April 2021, a study on PubMed was performed. COVID-19, 17-estradiol (E2), immunoregulatory properties, pregnancy, menopausal symptoms, hormonal therapy,
ER/ expression on immune cells, and mortality were some of the concepts used in the search.

Regulation of pro-inflammatory immune processes against COVID-19 appears to be associated with increased immune function (pro-inflammatory), anti-inflammatory regulation, and antiviral defense. Women with a severe coronavirus infection had higher serum IgG antibody levels than men, and their IgG production was faster in the early stages of infection. 17-estradiol (E2) levels of blood will increase by 100-fold during pregnancy. COVID-19 in pregnant women had a 15-fold lower mortality rate than other women. While menopause replacement therapy (MRT) for pre/post-menopausal women and its effectiveness in reducing COVID-19 infection is debatable.

MRT may be considered as a viable treatment option for pre/post-menopause women with coronavirus, referring to the fact that sex hormones reduce inflammatory responses and modulate
ACE2 expression. The task's difficulty and achieving the desired outcome seem to be challenging.

 Aflatoxin (AF) is a mycotoxin produced by various strains of the Aspergillus</em> family. AFG1 as one of the most important types is highly found in cereals and grains. AF affects sperm production or even its quality. This study was designed to test the effects of AFG1 on mice testicular tissue. 

Experimental approach:

Twenty-four Albino mice were divided into four groups of 6 each; a control group (0.2 mL corn oil and ethanol), three treatment groups with different periods (20 µg/kg AFG1 for 7, 15, and 35 consecutive days). All treatments were applied intraperitoneally. Biosynthesis of cyclin D1, p21, and estrogen receptor alpha (ERα) proteins was evaluated by immunohistochemistry (IHC) staining. Levels of cyclin D1, p21, and ERα mRNA were evaluated by the real-time polymerase chain reaction (RT-PCR) technique. Tubular differentiation index (TDI), reproductive index (RI), and spermiogenesis indices were also analyzed.

 AFG1 increased the percentage of seminiferous tubules with negative TDI, RI, and SPI compared to the control group (P</em> < 0.05). RT-PCR and IHC analyses illustrated time-dependent enhancement in p21 expression and cyclin D1 biosynthesis in AFG1-treated groups significantly (P</em> < 0.05). While the protein and mRNA levels of ERα were significantly (P</em> < 0.05) decreased in a time-dependent manner.

Conclusion and implications:

 The chronic exposure to AFG1 reduced the expression and synthesis of ERα, increased the expression and synthesis of p21 and cyclin D1, impaired apoptosis, which in turn could impair spermatogenesis. </strong>

In recent years, the potential of marine natural products as anticancer agents, specifically for breast cancer, has been examined. The sea cucumber (Holothuroidea: Echinodermata) is known to contain triterpene glycosides, which have shown anticancer or cytotoxic activity. In this research, molecular docking of selected sea cucumber bioactive compounds was conducted on five receptor targets that play an important role in breast cancer: estrogen receptor alpha (ER-α), fibroblast growth factor receptor 1 (FGFR1), vascular endothelial growth factor receptor 2 (VEGFR2), progesterone receptor (PR), and insulin-like growth factor 1 receptor (IGFR1). The purpose of this was to observe the interaction between active compounds and the active site of breast cancer receptor targets. Holothurin A gave the lowest binding energy (-7.1 kcal/mol) and was involved in a hydrogen bond with amino acid His-516 when superposition towards to E4D cocrystal was present. Holothurin A also had a similar posing with raloxifene, in which the hydrogen bond with His-516 with a RMSD value of 3.3 Å was observed with superposition towards to the positive control raloxifene. The analysis and visualization results of 24-dehidroechinoside that was superposed on E4D cocrystal, BMI cocrystal, and positive control raloxifene showed that 24-dehidroechinoside had a hydrophobic interaction with amino-acid residue Leu-346, a strong hydrogen bond to Gln-977, as well as a hydrogen bond to Thr-347 in a distance of 3.7 Å, and a hydrophobic interaction with amino-acid residue Ala-350. The most potent in silico anti-breast cancer compounds in sea cucumbers are holothurin A and 24-dehidroechinoside. Holothurin A is active as an anti-breast cancer agent by inhibiting ER-α, while 24-dehidroechinoside inhibits both ER-α and IGFR1.

Gliomas are the most common type of primary intracranial tumors in adults. The expression of estrogen receptors varies in different grades of glial tumors, and some studies have suggested that this expression might have a prognostic value. It seems that estrogen receptor expression negatively correlates with the histological grade of gliomas. In the present study, we aimed to determine the expression of estrogen receptor in different glial tumors in Iranian patients and to find a possible correlation between its expression and the grade of glial tumors.

The brain tumors pathology reports from 2014 to 2017 in the Pathology Department of Shohaday-e Tajrish Hospital in Tehran, Iran were evaluated and 104 different gliomas: 79 cases of astrocytoma and 25 cases of oligodendroglioma were selected. All the samples were re-evaluated by a neuropathologist in order to accurately determine the tumor grade. The immunohistochemistry was carried out to detect the expression of estrogen receptor alpha and beta on brain tumors.

None of the samples expressed estrogen receptor alpha. In the case of estrogen receptor beta (ERβ), all samples showed various degrees of positivity: 9% weak, 40% moderate, and 51% strong expressions. The level of ERβ expression was found to be conversely correlated with tumor grade.

Our study demonstrated that ERβ is expressed in the majority (if not all) of the glial tumors and its expression was conversely related to the tumor grade. Because of well-tolerability and acceptable adverse effects, ER agonists might be considered as therapeutic agents for the patients with glial tumors.

microRNAs (miRNAs) play bifunctional roles in the initiation and progression of cancer, and recent evidence has confirmed that unusual expression of miRNAs is required for the progress of breast cancer. The regulatory role of aryl hydrocarbon receptor (AhR) and its endogenous ligand, 6-formylindolo[3,2-b]carbazole (FICZ) on the expression of tumor suppressor miRNAs, miR-22, miR-515-5p and miR-124-3p, as well as their association with the estrogen receptor alpha (ERα) were the aims of this study.

In this experimental study, the expression levels of miR-22, miR-515-5p, miR-124-3p and miR-382-5p in MCF-7 cells were determined using the quantificational real time polymerase chain reaction (qRT-PCR) assay.

Our results revealed that miR-22, miR-515-5p, and miR-124-3p expressions were significantly increased in cells transfected with ERα siRNA. Our data also showed that miR-22, miR 515-5p, and miR-124-3p expression levels were significantly increased following FICZ treatment. Here, we found that AhR/ERα cross-talk plays a critical role in the expression of miR-22, miR-515-5p and miR-124-3p in MCF-7 cells.

Overall, our data demonstrated that FICZ, as an AhR agonist could induce the expression of tumor suppressor miRNAs, miR-22, miR-515-5p, and miR-124-3p; thus, FICZ might be regarded as a potential therapeutic agent for breast cancer treatment. 

Tamoxifen (TAM) is an important drug for treatment of breast cancer. It is most effective against estrogen receptor-positive and negative breast cancer. Protective adjuvant is another applied of TAM for women at risk of development of breast cancer. Anti-cancer activity of TAM can take various pathways of action. Antagonistic with estrogen receptor and oxidation reaction are the most proposed mechanism of action of TAM in cancer cells. Recently, many studies focused on the potential antimicrobial action of TAM. Fungi are demonstrated to affect by TAM through various mechanism of action. Yeasts, especially Candida albicans</em>, are the most common type of fungi used to test the antifungal action of TAM. Inhibitory action on some components of the calcium-calcineurin pathway in fungal cells is most acceptable mechanism of TAM action. TAM can also play a synergistic role to increase the antifungal activity of other standard agents. This review will discuss the most recent information about antifungal action of TAM.

Rutin (quercetin-3-rhamnosyl-glucoside), a flavonoid, is derived from plants and has antioxidant properties. This study aimed to evaluate the effect of different concentrations of rutin on mouse ovary heterotopic allotransplantation. The present animal experimental study was conducted on 40 female adult Balb/c mice weighing 30 ± 5 g at the Jundishapur University of Medical Sciences, Ahvaz, Iran, during 2016 - 2018. The mice were divided by permuted block randomization into 8 groups (n = 5): OVX (ovariectomy), as the negative control; normal (positive control); OVX + OVA (ovariectomy and transplantation) (control), treated with 0.5 mL of normal saline; OVX + OVA + 10 mg/kg of rutin; OVX + OVA + 30 mg/kg of rutin; OVX + OVA + 60 mg/kg of rutin; OVX + OVA + 100 mg/kg of rutin; and the autograft. Groups were treated daily. Fourteen days after transplantation, ovarian grafts were collected and processed histologically for follicle number counting. Serum estrogen (E2) and progesterone (P4) levels were evaluated. Furthermore, the expression of Estrogen Receptor alpha (ERα), Estrogen Receptor beta (ERβ), and Progesterone Receptor (PR) in the uterine endometrial tissue was tested using qRT-PCR and western blotting. A decrease in the number of mature follicles and increase in the number of atretic follicles (mean ± SD: OVX + OVA + 30 = 19.00 ± 1.000, OVX + OVA + 60 = 25.00 ± 5.000, and OVX + OVA + 100 = 23.00 ± 2.646) were observed in all groups treated with rutin in comparison with the control group (mean ± SD: 12.33 ± 2.517) (P value < 0.05). The level of E2 and P4 (mean ± SD: OVX + OVA + 100 = 6.133 ± 1.026) increased in comparison with the OVX + OVA group (mean ± SD: 0.4667 ± 0.2517) (P value < 0.05). The protein expression of ERα (mean ± SD: OVX + OVA + 10 = 1.615 ± 0.1701 and OVX + OVA + 30 = 1.744 ± 0.1779) in comparison with the control group (mean ± SD: 0.7089 ± 0.1131), and ERβ (mean ± SD: OVX + OVA + 10 = 0.7747 ± 0.4365, OVX + OVA + 30 = 0.9220 ± 0.1245, OVX + OVA + 60 = 0.7701 ± 0.2150, and OVX + OVA + 100 = 0.6676 ± 0.1547) increased in a dose-dependent manner in all groups treated with rutin in comparison with the OVX + OVA group (mean ± SD: 0.1534 ± 0.06109) (P value < 0.05). No significant changes in PR were found in groups treated with rutin in comparison with the control group. The results of the present study indicated that rutin increases E2 and P4 levels in ovarian hetero allograft mice. Rutin also upregulated the expression of ERα and ERβ but had no significant effect on PR.

Features of malignant melanoma (MM) vary in the different geographic regions of the world. This may be attributable to environmental, ethnic, and genetic factors. The aim of this study was to determine the expression of estrogen receptor alpha (ER‑α) in MM in Isfahan, Iran.

This study was planned as a descriptive, analytical, cross‑sectional investigation. During this study, paraffin‑embedded tissue blocks of patients with a histopathologic diagnosis of MM was studied for ER‑α using immunohistochemistry (IHC).

In this study, 38 patients (female/male; 20/18) with a definite diagnosis of malignant cutaneous melanoma and mean age of 52.4 ± 11.2 years were investigated. Using envision IHC staining, there were not any cases with ER‑α expression.

In confirmation to the most previous studies, expression of ER‑α was negative in MM. It is recommended to investigate the expression of estrogen receptor beta and other markers in MM.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. This cancer may be due to a multistep process with an accumulation of epigenetic alterations in tumor suppressor genes (TSGs), leading to hypermethylation of the genes. Hypermethylation of TSGs is associated with silencing and inactivation of them. It is well‑known that DNA hypomethylation is the initial epigenetic abnormality recognized in human tumors. Estrogen receptor alpha (ERα) is one of the TSGs which modulates gene transcription and its hypermethylation is because of overactivity of DNA methyltransferases. Fortunately, epigenetic changes especially hypermethylation can be reversed by pharmacological compounds such as genistein (GE) and 17‑beta estradiol (E2) which involve in preventing the development of certain cancers by maintaining a protective DNA methylation. The aim of the present study was to analyze the effects of GE on ERα and DNMT1 genes expression and also apoptotic and antiproliferative effects of GE and E2 on HCC.

Cells were treated with various concentrations of GE and E2 and the 3‑(4,5‑dimethyl‑2‑thiazolyl)‑2,5‑diphenyl‑2H‑tetrazolium bromide assay was used. Furthermore, cells were treated with single dose of GE and E2 (25 μM) and flow cytometry assay was performed. The expression level of the genes was determined by quantitative real‑time reverse transcription polymerase chain reaction.

GE increased ERα and decreased DNMT1 genes expression, GE and E2 inhibited cell viability and induced apoptosis significantly.

GE can epigenetically increase ERα expression by inhibition of DNMT1 expression which in turn increases apoptotic effect of E2. Furthermore, a combination of GE and E2 can induce apoptosis more significantly.

Lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. Although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormonedependent cancers. Phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitive decline. 24 female Wistar rats weighing 180-220 g were used in this study. The animals were ovariectomized and randomly divided into four groups including, control and two groups which received 8 and 80 mg/kg Vitex agnus castus (VAC) ethanolic extract orally. The last groups were treated with 40 μg/kg of estradiol valerat. Step-through passive avoidance (STPA) test was used for the evaluation of learning and memory. The hippocampal estrogen receptor α (ERα) expression was measured using Real-Time PCR. The results demonstrated that VAC extract or estradiol had better performance on stepthrough passive avoidance test than control group (all P<0.05). Moreover, administration of either estradiol or VAC extract increased the hippocampal mRNA level of ERα and prevented the decrease in uterine weight of ovariectomized rats. Based on our data, VAC extract improves learning and memory in ovariectomized rats. The positive effect of VAC extract on learning and memory is possibly associated with an increase in ERα gene expression in the hippocampal formation.