Knockdown of estrogen receptor β increases proliferation and affects the transcriptome of endometrial adenocarcinoma cells

The Role of Estrogen across Multiple Disease Mechanisms

Estrogen is a significant hormone that is involved in a multitude of physiological and pathological processes. In addition to its pivotal role in the reproductive system, estrogen is also implicated in the pathogenesis of a multitude of diseases. Nevertheless, previous research on the role of estrogen in a multitude of diseases, including Alzheimer's disease, depression, cardiovascular disease, diabetes, osteoporosis, gastrointestinal diseases, and estrogen-dependent cancers, has concentrated on a single disease area, resulting in a lack of comprehensive understanding of cross-disease mechanisms. This has brought some challenges to the current treatment methods for these diseases, because estrogen as a potential therapeutic tool has not yet fully developed its potential. Therefore, this review aims to comprehensively explore the mechanism of estrogen in these seven types of diseases. The objective of this study is to describe the relationship between each disease and estrogen, including the ways in which estrogen participates in regulating disease mechanisms, and to outline the efficacy of estrogen in treating these diseases in clinical practice. By studying the role of estrogen in a variety of disease mechanisms, it is hoped that a more accurate theoretical basis and clinical guidance for future treatment strategies will be provided, thus promoting the effective management and treatment of these diseases.

Exploring the multi-targeting phytoestrogen potential of Calycosin for cancer treatment: A review

Cancer remains a significant challenge in the field of oncology, with the search for novel and effective treatments ongoing. Calycosin (CA), a phytoestrogen derived from traditional Chinese medicine, has garnered attention as a promising candidate. With its high targeting and low toxicity profile, CA has demonstrated medicinal potential across various diseases, including cancers, inflammation, and cardiovascular disease. Studies have revealed that CA possesses inhibitory effects against a diverse array of cancers. The underlying mechanism of action involves a reduction in tumor cell proliferation, induction of tumor cell apoptosis, and suppression of tumor cell migration and invasion. Furthermore, CA has been shown to enhance the efficacy of certain chemotherapeutic drugs, making it a potential component in treating malignant tumors. Given its high efficacy, low toxicity, and multi-targeting characteristics, CA holds considerable promise as a therapeutic agent for cancer treatment. The objective of this review is to present a synthesis of the current understanding of the antitumor mechanism of CA and its research progress.

Role of Estrogen Receptor β, G-Protein Coupled Estrogen Receptor and Estrogen-Related Receptors in Endometrial and Ovarian Cancer

Ovarian and endometrial cancers are affected by estrogens and their receptors. It has been long known that in different types of cancers, estrogens activate tumor cell proliferation via estrogen receptor α (ERα). In contrast, the role of ERs discovered later, including ERβ and G-protein-coupled ER (GPER1), in cancer is less well understood, but the current state of knowledge indicates them to have a considerable impact on both cancer development and progression. Moreover, estrogen related receptors (ERRs) have been reported to affect pathobiology of many tumor types. This article provides a summary and update of the current findings on the role of ERβ, GPER1, and ERRs in ovarian and endometrial cancer. For this purpose, original research articles on the role of ERβ, GPER1, and ERRs in ovarian and endometrial cancers listed in the PubMed database have been reviewed.

Loss of HOXA10 causes endometrial hyperplasia progressing to endometrial cancer

Endometrial cancer is the fourth most common malignancy in women and the precursor lesion is endometrial hyperplasia. HOXA10 is a transcription factor that plays key roles in endometrial functions such as the endowment of receptivity, embryo implantation, and trophoblast invasion. Herein, using testicular transgenesis, we developed transgenic mice that expressed a shRNA against HOXA10 and there was a nearly 70% reduction in the expression of HOXA10 in these animals. We observed that downregulation of HOXA10 led to the development of endometrial hyperplasia in the young animals (3 months), and as they aged (>1 year), most animals developed well-differentiated endometrial adenocarcinoma. In the endometrium of animals with reduced HOXA10, there was increased proliferation and elevated levels of ERα and ERβ. In parallel, there was increased expression of Wnt4 and β-Catenin, SOX9, and YAP1. We propose that chronic reduction in HOXA10 expression disrupts multiple pathways in the uterus that aids in the development of endometrial hyperplasia which progresses to endometrial cancer with age.

Bisphenol S Increases Cell Number and Stimulates Migration of Endometrial Epithelial Cells

OBJECTIVE

To determine whether bisphenol S (BPS), a common substitute for bisphenol A (BPA), induces cell proliferation and migration in human endometrial epithelial cells (Ishikawa) and adult mouse uterine tissues.

METHODOLOGY

Human endometrial Ishikawa cells were exposed to low doses of BPS (1 nM and 100 nM) for 72 hours. Cell proliferation was assessed through the viability assays MTT and CellTiter-Glo®. Wound healing assays were also used to evaluate the migration potential of the cell line. The expression of genes related to proliferation and migration was also determined. Similarly, adult mice were exposed to BPS at a dose of 30 mg/kg body weight/day for 21 days, after which, the uterus was sent for histopathologic assessment.

RESULTS

BPS increased cell number and stimulated migration in Ishikawa cells, in association with the upregulation of estrogen receptor beta (ESR2) and vimentin (VIM). In addition, mice exposed to BPS showed a significantly higher mean number of endometrial glands within the endometrium.

CONCLUSION

Overall, in vitro and in vivo results obtained in this study showed that BPS could significantly promote endometrial epithelial cell proliferation and migration, a phenotype also observed with BPA exposure. Hence, the use of BPS in BPA-free products must be reassessed, as it may pose adverse reproductive health effects to humans.

Estradiol mediates the interaction of LINC01541 and miR-429 to promote angiogenesis of G1/G2 endometrioid adenocarcinoma in-vitro: A pilot study

Background

Endometrioid adenocarcinoma (EAC) is the most common subtype of endometrial cancer (EC) and is an estrogen-related cancer. In this study, we sought to investigate the expressions and mechanism of action of 17β-estradiol (E2) and long noncoding RNA (lncRNA) LINC01541 in G1/G2 EAC samples.

Methods

The expressions of estrogen receptor β (ESR2), LINC01541, miR-200s, and VEGFA were evaluated using real-time PCR in human EAC tissues (n = 8) and adjacent normal tissues (n = 8). Two EC cell lines (Ishikawa and RL95-2) were selected for validation in vitro. Bioinformatics analyses and luciferase reporter analyses were performed to verify potential binding sites. qRT-PCR, Western blot, and CCK-8 were used to identify the regulatory mechanisms of related genes in cell biological behavior.

Results

Compared with adjacent normal tissues, LINC01541 and miR-200s family (except miR-200c) were highly expressed in EAC tissues (n=8), while ESR2 and VEGFA were lowly expressed in EAC tissues (* P < 0.05; ** P < 0.01). In vitro: E2 inhibited the expression of LINC01541 and miR-429 in both cell lines, and estrogen antagonist (PHTPP) could reverse this effect, in addition, PHTPP could promote the proliferation of these two cancer cells, cell transfection LINC01541 also had this effect after overexpression of plasmid and miR-429 mimic. E2 promotes the expression of VEGFA in both cell lines, and PHTPP can also reverse this effect. LINC01541 interacts with miR-429 to promote the expression of each other, and both inhibit the synthesis of VEGFA in EAC cells after overexpression. Through the double validation of bioinformatics analysis and dual fluorescein reporter gene, it was confirmed that miR-429 targets the regulation of VEGFA expression (* P < 0.05; ** P < 0.01).

Conclusion

E2 promotes the synthesis of VEGFA by altering the expression levels of LINC01541 and miR-429 in EAC, thereby affecting the angiogenesis process of EAC. Also, E2-mediated LINC01541/miR-429 expression may affect cell migration in EAC. In addition, we identified a reciprocal promotion between LINC01541 and miR-429.

Estrogen Receptors-Mediated Apoptosis in Hormone-Dependent Cancers

It is known that estrogen stimulates growth and inhibits apoptosis through estrogen receptor(ER)-mediated mechanisms in many cancer cell types. Interestingly, there is strong evidence that estrogens can also induce apoptosis, activating different ER isoforms in cancer cells. It has been observed that E2/ERα complex activates multiple pathways involved in both cell cycle progression and apoptotic cascade prevention, while E2/ERβ complex in many cases directs the cells to apoptosis. However, the exact mechanism of estrogen-induced tumor regression is not completely known. Nevertheless, ERs expression levels of specific splice variants and their cellular localization differentially affect outcome of estrogen-dependent tumors. The goal of this review is to provide a general overview of current knowledge on ERs-mediated apoptosis that occurs in main hormone dependent-cancers. Understanding the molecular mechanisms underlying the induction of ER-mediated cell death will be useful for the development of specific ligands capable of triggering apoptosis to counteract estrogen-dependent tumor growth.

BAG2-Mediated Inhibition of CHIP Expression and Overexpression of MDM2 Contribute to the Initiation of Endometriosis by Modulating Estrogen Receptor Status

Endometriosis is an estrogen-dependent gynecological disease primarily affecting women of childbearing age, which gives rise to pelvic pain calling for multiple operations, and sometimes leading to infertility. However, the etiology of endometriosis remains poorly understood. In this study we investigated the roles of two Ubiquitin E3 Ligases, namely hsc70-interacting protein (CHIP) and mouse double minute 2 (MDM2), in the abnormal estrogenic activity in endometriosis. We first collected endometrial tissues from 91 cases of endometriosis and 78 cases of uterine myomas. Next, we established a murine endometriosis model by ectopic endometrial tissue implantation. In other studies, we isolated human endometrial stromal cells (HESCs) were isolated from the endometrial tissues, and performed HA- or FLAG-immunoprecipitation assays and immunoblotting with an anti-ubiquitin antibody to test the interactions among BAG2, CHIP, MDM2, estrogen receptor α (ERα), and ERβ. The expression of ERα was downregulated while that of ERβ, BAG2, and MDM2 was upregulated in human endometriosis and in the mouse model. CHIP degraded ERβ instead of ERα via the ubiquitin-proteasome pathway, while BAG2 impaired the CHIP-mediated degradation of ERβ in cultured HESCs derived from human endometriosis. The degradation of ERα by MDM2 in cultured endometriosis-HESCs also occurred through the ubiquitin-proteasome pathway. Knockdown of both BAG2 and MDM2 alleviated the development of endometriosis in mice. Our findings suggest that the interference of BAG2 and MDM2 may have therapeutic effects in endometriosis. Understanding better the molecular mechanisms underlying the regulation of the abnormal estrogenic activity in endometriosis is crucial for the advancement of targeted therapeutic strategies.

Estrogen Receptors Alpha and Beta in Acute Myeloid Leukemia

Estrogen receptor (ER) signaling has been widely studied in a variety of solid tumors, where the differential expression of ERα and ERβ subtypes can impact prognosis. ER signaling has only recently emerged as a target of interest in acute myeloid leukemia (AML), an aggressive hematological malignancy with sub-optimal therapeutic options and poor clinical outcomes. In a variety of tumors, ERα activation has proliferative effects, while ERβ targeting results in cell senescence or death. Aberrant ER expression and hypermethylation have been characterized in AML, making ER targeting in this disease of great interest. This review describes the expression patterns of ERα and ERβ in AML and discusses the differing signaling pathways associated with each of these receptors. Furthermore, we assess how these signaling pathways can be targeted by various selective estrogen receptor modulators to induce AML cell death. We also provide insight into ER targeting in AML and discuss pending questions that require further study.

Calycosin induces apoptosis in osteosarcoma cell line via ERβ‑mediated PI3K/Akt signaling pathways

Previous studies have shown that calycosin, a natural phytoestrogen which is structurally similar to estrogen, inhibits proliferation and induces apoptosis in estrogen-dependent cancer types via the estrogen receptor (ER)β-induced inhibition of PI3K/Akt. Therefore, the aims of the present study were to investigate the effects of calycosin on human osteosarcoma (OS), and to examine the molecular mechanisms associated with ERβ. Human OS MG-63 cells were treated with various concentrations of calycosin, and MTT and flow cytometry assays were used to assess the effects of calycosin on cellular proliferation and apoptosis. In addition, protein expression levels of ERβ, phosphorylated (p)-PI3K, p-Akt, cleaved poly (ADP-ribose) polymerase 1 (PARP) and cleaved caspase-3 were evaluated by western blot analysis. The present results suggested that calycosin inhibited proliferation and induced apoptosis in MG-63 cells. Furthermore, increased ERβ expression was detected in OS MG-63 cells treated with calycosin, and an ERβ inhibitor (PHTPP) reversed calycosin-induced cytotoxicity and apoptosis. Moreover, phosphorylation levels of PI3K and Akt were significantly downregulated after calycosin treatment, whereas PHTPP reversed their phosphorylation. ERβ-mediated PI3K/Akt downstream signaling pathways were found to influence the activity of poly (ADP-ribose) polymerase 1 and caspase-3. Thus, the present results indicated that calycosin inhibited proliferation and induced apoptosis in OS MG-63 cells, and that these effects were mediated by ERβ-dependent inhibition of the PI3K/Akt pathways.

Endometrial preparation for frozen-thawed embryo transfer in an artificial cycle: transdermal versus vaginal estrogen

The objective was to compare the endometrial thickness (ET) in a frozen embryo transfer (FET) cycle between transdermal and vaginal estrogen. Our secondary objectives were to compare the patient satisfaction and the pregnancy outcomes. Prospective monocentric cohort study between 01/2017 and 12/2017 at a single institution. Choice of administration was left to the patient. 119 cycles had transdermal estrogen (T-group) and 199 had vaginal estrogen (V-group). The ET at 10 ± 1 days of treatment was significantly higher in the T-group compared to the V-group (9.9 vs 9.3 mm, p = 0.03). In the T-group, the mean duration of treatment was shorter (13.6 vs 15.5 days, p < 0.001). The rate of cycle cancelation was comparable between the two groups (12.6% vs 8.5%, p = 0.24). Serum estradiol levels were significantly lower (268 vs 1332 pg/ml, p < 0.001), and serum LH levels were significantly higher (12.1 ± 16.5 vs 5 ± 7.5 mIU/ml, p < 0.001) in the T-group. Patient satisfaction was higher in the T-group (p = 0.04) and 85.7% (36/42) of women who had received both treatments preferred the transdermal over the vaginal route. Live birth rates were comparable between the two groups (18% vs 19%, p = 0.1). Transdermal estrogen in artificial FET cycles was associated with higher ET, shorter treatment duration and better tolerance.