Integration of the extranuclear and nuclear actions of estrogen

Association Between Female Sex and Better Survival in Gastroenteropancreatic Neuroendocrine Tumors

INTRODUCTION

Studies conflict on whether sex influences survival in gastroenteropancreatic neuroendocrine tumors (GEP-NETs). GEP-NETs express receptors and genes responsive to female hormones. We hypothesized that women would have improved survival and this difference would be greater in premenopausal age women compared to older women.

MATERIALS AND METHODS

The National Cancer Database from 2004 to 2016 was queried for patients with GEP-NETs based on histologic code. Demographic, tumor, treatment, and socioeconomic characteristics were compared between men and women and age ≤45 or >65 y using Fisher's exact and Wilcoxon tests as appropriate. The primary endpoint was overall survival (OS), assessed by Kaplan-Meier survival analysis.

RESULTS

Included in the study were 73,521 patients with small bowel neuroendocrine tumors (SBNETs), gastric neuroendocrine tumors (GNETs), or pancreas neuroendocrine tumors (36,197 female, 37,324 male). Women lived longer regardless of primary site, with the largest difference in GNETs (median OS 139 versus 85 mo) and smallest in SBNETs (121 versus 116, P < 0.001 for both). While male patients more often had high grade and metastatic disease, female sex remained independently associated with improved OS after adjusting for confounders (hazard ratio 0.84, P < 0.001). In GNETs and SBNETs, female sex had a larger beneficial effect on OS in premenopausal than postmenopausal patients.

CONCLUSIONS

Women with GEP-NETs have improved survival over men, especially in the premenopausal age group. This may be due to a protective effect of female hormones; however, further studies are necessary to uncover the biologic basis of this difference.

Design, synthesis, and cytotoxicity of ibuprofen-appended benzoxazole analogues against human breast adenocarcinoma

A library of novel ibuprofen-appended benzoxazole analogues (7a-l) was synthesized via a series of nitration, reduction, and condensation-cyclization reactions and screened for their in vitro anticancer activity against human breast cancer MCF-7 and MDA-MB-231 cell lines using doxorubicin as a standard reference. Compounds 7h and 7j displayed outstanding activity against the MCF-7 cell line with an IC50 value of 8.92 ± 0.91 μM and 9.14 ± 8.22 μM, respectively, compared to the doxorubicin IC50 value of 9.29 ± 1.02 μM. Compound 7h also exhibited outstanding activity against the MDA-MB-231 cell line with an IC50 value of 7.54 ± 0.95 μM compared to the doxorubicin IC50 value of 7.68 ± 5.36 μM. Compounds 7h, 7i, 7j, and 7g showed identical morphological changes to those showed by doxorubicin. The molecular docking study against ERα unveiled their best docking scores and binding interactions in agreement to experimental results. Pharmacokinetics prediction envisaged their drug-like properties suitable for therapeutic applications.

The Role of Estrogen and Estrogen Receptors in Head and Neck Tumors

Head and neck squamous cell carcinoma (HNSCC) is the most common histological form of head and neck tumors (HNTs), which originate from the epithelium of the lips and oral cavity, pharynx, larynx, salivary glands, nasal cavity, and sinuses. The main risk factors include consumption of tobacco in all forms and alcohol, as well as infections with high-risk human papillomaviruses or the Epstein-Barr virus. Regardless of the etiological agent, the risk of developing different types of HNTs is from two to more than six times higher in males than in females. The reason for such disparities probably lies in a combination of both biological and psychosocial factors. Therefore, it is hypothesized that exposure to female sex hormones, primarily estrogen, provides women with protection against the formation and metastasis of HNTs. In this review, we synthesized available knowledge on the role of estrogen and estrogen receptors (ERs) in the development and progression of HNTs, with special emphasis on membrane ERs, which are much less studied. We can summarize that in addition to epidemiologic studies unequivocally pointing to the protective effect of estrogen in women, an increased expression of both nuclear ERs, ERα, and ERβ, and membrane ERs, ERα36, GPER1, and NaV1.2, was present in different types of HNSCC, for which anti-estrogens could be used as an effective therapeutic approach.

Label-free visualization and quantification of the drug-type-dependent response of tumor spheroids by dynamic optical coherence tomography

We demonstrate label-free dynamic optical coherence tomography (D-OCT)-based visualization and quantitative assessment of patterns of tumor spheroid response to three anti-cancer drugs. The study involved treating human breast adenocarcinoma (MCF-7 cell-line) with paclitaxel (PTX), tamoxifen citrate (TAM), and doxorubicin (DOX) at concentrations of 0 (control), 0.1, 1, and 10 µM for 1, 3, and 6 days. In addition, fluorescence microscopy imaging was performed for reference. The D-OCT imaging was performed using a custom-built OCT device. Two algorithms, namely logarithmic intensity variance (LIV) and late OCT correlation decay speed (OCDS[Formula: see text]) were used to visualize the tissue dynamics. The spheroids treated with 0.1 and 1 µM TAM appeared similar to the control spheroid, whereas those treated with 10 µM TAM had significant structural corruption and decreasing LIV and OCDS[Formula: see text] over treatment time. The spheroids treated with PTX had decreasing volumes and decrease of LIV and OCDS[Formula: see text] signals over time at most PTX concentrations. The spheroids treated with DOX had decreasing and increasing volumes over time at DOX concentrations of 1 and 10 µM, respectively. Meanwhile, the LIV and OCDS[Formula: see text] signals decreased over treatment time at all DOX concentrations. The D-OCT, particularly OCDS[Formula: see text], patterns were consistent with the fluorescence microscopic patterns. The diversity in the structural and D-OCT results among the drug types and among the concentrations are explained by the mechanisms of the drugs. The presented results suggest that D-OCT is useful for evaluating the difference in the tumor spheroid response to different drugs and it can be a useful tool for anti-cancer drug testing.

Sex Differences in Colon Cancer: Genomic and Nongenomic Signalling of Oestrogen

Colon cancer (CRC) is a prevalent malignancy that exhibits distinct differences in incidence, prognosis, and treatment responses between males and females. These disparities have long been attributed to hormonal differences, particularly the influence of oestrogen signalling. This review aims to provide a comprehensive analysis of recent advances in our understanding of the molecular mechanisms underlying sex differences in colon cancer and the protective role of membrane and nuclear oestrogen signalling in CRC development, progression, and therapeutic interventions. We discuss the epidemiological and molecular evidence supporting sex differences in colon cancer, followed by an exploration of the impact of oestrogen in CRC through various genomic and nongenomic signalling pathways involving membrane and nuclear oestrogen receptors. Furthermore, we examine the interplay between oestrogen receptors and other signalling pathways, in particular the Wnt/β-catenin proliferative pathway and hypoxia in shaping biological sex differences and oestrogen protective actions in colon cancer. Lastly, we highlight the potential therapeutic implications of targeting oestrogen signalling in the management of colon cancer and propose future research directions to address the current gaps in our understanding of this complex phenomenon.

Regulation of mRNA translation by estrogen receptor in breast cancer

Breast cancer is one of the leading causes of cancer-related fatalities and the most often diagnosed malignancy in women globally. Dysregulation of sex hormone signaling pathways mediated by the estrogen receptor (ER) in breast cancer is well characterized. Although ER is known to promote cell growth and survival by altering gene transcription, recent research suggests that its effects in cancers are also mediated through dysregulation of protein synthesis. This implies that ER can coordinately affect gene expression through both translational and transcriptional pathways, leading to the development of malignancy. In this review, we will cover the current understanding of how the ER controls mRNA translation in breast cancer and discuss any potential clinical implications of this phenomenon.

Ovariectomy induces hyperalgesia accompanied by upregulated estrogen receptor α and protein kinase B in the rat spinal cord

Hormone supplementation is one of the common therapies for menopause-related disorders. Among different tools, the ovariectomy (OVX) rodents are widely accepted as an appropriate menopausal pain model. Our previous study has showed that OVX produces a significant pain facilitation in both acute pain and tonic pain, however, the underlying mechanisms remain unclear. In this study, we examined the effects of OVX treatment and estradiol (E2) supplementation on formalin-induced nociceptive responses, and explored the associated spinal mechanisms. Female Sprague-Dawley rats underwent bilateral OVX, and E2 supplementation was given subcutaneously from the 5th week after surgery (30 μg/day for 7 days). Our results showed that formalin-induced nociceptive behaviors did not differ between diestrus and proestrus stages of the estrous in intact rats. However, OVX exacerbated formalin-evoked inflammatory pain, especially in the late phase at 4-5 weeks but not 2 weeks post-surgery. E2 supplementation significantly reversed the OVX-triggered hyperalgesia. Double immunofluorescence staining revealed that both ERα and ERβ in the spinal dorsal horn were co-labeled with the neuronal markers, but not with markers of astrocytes or microglia. The spinal ERα (but not ERβ) expression significantly increased in the OVX group, which was reversed by E2 supplementation. Moreover, the OVX individuals showed an increased protein kinase B (AKT) level in lumbar spinal cord, and E2 supplementation diminished the AKT expression in OVX rats. Finally, intrathecal injection Wortmannin, an inhibitor for AKT signaling, effectively reduced the nociceptive behaviors in the late phase and the number of c-fos positive cells. Together, our findings indicate that E2 supplementation alleviates the OVX-induced hyperalgesia, which might be involved in spinal ERα and AKT mechanisms.

Oestrogen receptor-independent actions of oestrogen in cancer

Oestrogen, the primary female sex hormone, plays a significant role in tumourigenesis. The major pathway for oestrogen is via binding to its receptor [oestrogen receptor (ERα or β)], followed by nuclear translocation and transcriptional regulation of target genes. Almost 70% of breast tumours are ER + , and endocrine therapies with selective ER modulators (tamoxifen) have been successfully applied. As many as 25% of tamoxifen-treated patients experience disease relapse within 5 years upon completion of chemotherapy. In such cases, the ER-independent oestrogen actions provide a plausible explanation for the resistance, as well as expands the existing horizon of available drug targets. ER-independent oestrogen signalling occurs via one of the following pathways: signalling through membrane receptors, oxidative catabolism giving rise to genotoxic metabolites, effects on mitochondria and redox balance, and induction of inflammatory cytokines. The current review focuses on the non-classical oestrogen signalling, its role in cancer, and its clinical significance.

Endothelial ERα promotes glucose tolerance by enhancing endothelial insulin transport to skeletal muscle

The estrogen receptor (ER) designated ERα has actions in many cell and tissue types that impact glucose homeostasis. It is unknown if these include mechanisms in endothelial cells, which have the potential to influence relative obesity, and processes in adipose tissue and skeletal muscle that impact glucose control. Here we show that independent of impact on events in adipose tissue, endothelial ERα promotes glucose tolerance by enhancing endothelial insulin transport to skeletal muscle. Endothelial ERα-deficient male mice are glucose intolerant and insulin resistant, and in females the antidiabetogenic actions of estradiol (E2) are absent. The glucose dysregulation is due to impaired skeletal muscle glucose disposal that results from attenuated muscle insulin delivery. Endothelial ERα activation stimulates insulin transcytosis by skeletal muscle microvascular endothelial cells. Mechanistically this involves nuclear ERα-dependent upregulation of vesicular trafficking regulator sorting nexin 5 (SNX5) expression, and PI3 kinase activation that drives plasma membrane recruitment of SNX5. Thus, coupled nuclear and non-nuclear actions of ERα promote endothelial insulin transport to skeletal muscle to foster normal glucose homeostasis.

Membrane estrogen receptor α signaling modulates the sensitivity to estradiol treatment in a dose- and tissue- dependent manner

Estradiol (E2) affects both reproductive and non-reproductive tissues, and the sensitivity to different doses of E2 varies between tissues. Membrane estrogen receptor α (mERα)-initiated signaling plays a tissue-specific role in mediating E2 effects, however, it is unclear if mERα signaling modulates E2 sensitivity. To determine this, we treated ovariectomized C451A females, lacking mERα signaling, and wildtype (WT) littermates with physiological (0.05 μg/mouse/day (low); 0.6 μg/mouse/day (medium)) or supraphysiological (6 μg/mouse/day (high)) doses of E2 (17β-estradiol-3-benzoate) for three weeks. Low-dose treatment increased uterus weight in WT, but not C451A mice, while non-reproductive tissues (gonadal fat, thymus, trabecular and cortical bone) were unaffected in both genotypes. Medium-dose treatment increased uterus weight and bone mass and decreased thymus and gonadal fat weights in WT mice. Uterus weight was also increased in C451A mice, but the response was significantly attenuated (- 85%) compared to WT mice, and no effects were triggered in non-reproductive tissues. High-dose treatment effects in thymus and trabecular bone were significantly blunted (- 34% and - 64%, respectively) in C451A compared to WT mice, and responses in cortical bone and gonadal fat were similar between genotypes. Interestingly, the high dose effect in uterus was enhanced (+ 26%) in C451A compared to WT mice. In conclusion, loss of mERα signaling reduces the sensitivity to physiological E2 treatment in both non-reproductive tissues and uterus. Furthermore, the E2 effect after high-dose treatment in uterus is enhanced in the absence of mERα, suggesting a protective effect of mERα signaling in this tissue against supraphysiological E2 levels.

CRISPR-Cas9 screen reveals a role of purine synthesis for estrogen receptor α activity and tamoxifen resistance of breast cancer cells

In breast cancer, resistance to endocrine therapies that target estrogen receptor α (ERα), such as tamoxifen and fulvestrant, remains a major clinical problem. Whether and how ERα⁺ breast cancers switch from being estrogen-dependent to estrogen-independent remains unclear. With a genome-wide CRISPR-Cas9 knockout screen, we identified previously unknown biomarkers and potential therapeutic targets of endocrine resistance. We demonstrate that high levels of PAICS, an enzyme involved in the de novo biosynthesis of purines, can shift the balance of ERα activity to be more estrogen-independent and tamoxifen-resistant. We find that this may be due to elevated activities of cAMP-activated protein kinase A and mTOR, kinases known to phosphorylate ERα specifically and to stimulate its activity. Genetic or pharmacological targeting of PAICS sensitizes tamoxifen-resistant cells to tamoxifen. Addition of purines renders them more resistant. On the basis of these findings, we propose the combined targeting of PAICS and ERα as a new, effective, and potentially safe therapeutic regimen.

Role of Sex Hormones in Prevalent Kidney Diseases

Chronic kidney disease (CKD) is a constantly growing global health burden, with more than 840 million people affected worldwide. CKD presents sex disparities in the pathophysiology of the disease, as well as in the epidemiology, clinical manifestations, and disease progression. Overall, while CKD is more frequent in females, males have a higher risk to progress to end-stage kidney disease. In recent years, numerous studies have highlighted the role of sex hormones in the health and diseases of several organs, including the kidney. In this review, we present a clinical overview of the sex-differences in CKD and a selection of prominent kidney diseases causing CKD: lupus nephritis, diabetic kidney disease, IgA nephropathy, and autosomal dominant polycystic kidney disease. We report clinical and experimental findings on the role of sex hormones in the development of the disease and its progression to end-stage kidney disease.

Both Nuclear and Membrane Estrogen Receptor Alpha Impact the Expression of Estrogen Receptors and Plasticity Markers in the Mouse Hypothalamus and Hippocampus

Estrogens via estrogen receptor alpha (ERα) genomic and nongenomic signaling can influence plasticity processes in numerous brain regions. Using mice that express nuclear only ERα (NOER) or membrane only ERα (MOER), this study examined the effect of receptor compartmentalization on the paraventricular nucleus of the hypothalamus (PVN) and the hippocampus. The absence of nuclear and membrane ERα expression impacted females but not males in these two brain areas. In the PVN, quantitative immunohistochemistry showed that the absence of nuclear ERα increased nuclear ERβ. Moreover, in the hippocampus CA1, immuno-electron microscopy revealed that the absence of either nuclear or membrane ERα decreased extranuclear ERα and pTrkB in synapses. In contrast, in the dentate gyrus, the absence of nuclear ERα increased pTrkB in synapses, whereas the absence of membrane ERα decreased pTrkB in axons. However, the absence of membrane only ERα decreased the sprouting of mossy fibers in CA3 as reflected by changes in zinc transporter immunolabeling. Altogether these findings support the idea that both membrane and nuclear ERα contribute overlapping and unique actions of estrogen that are tissue- and cellular-specific.

Network-informed discovery of multidrug combinations for ERα+/HER2-/PI3Kα-mutant breast cancer

Breast cancer is a persistent threat to women worldwide. A large proportion of breast cancers are dependent on the estrogen receptor α (ERα) for tumor progression. Therefore, targeting ERα with antagonists, such as tamoxifen, or estrogen deprivation by aromatase inhibitors remain standard therapies for ERα + breast cancer. The clinical benefits of monotherapy are often counterbalanced by off-target toxicity and development of resistance. Combinations of more than two drugs might be of great therapeutic value to prevent resistance, and to reduce doses, and hence, decrease toxicity. We mined data from the literature and public repositories to construct a network of potential drug targets for synergistic multidrug combinations. With 9 drugs, we performed a phenotypic combinatorial screen with ERα + breast cancer cell lines. We identified two optimized low-dose combinations of 3 and 4 drugs of high therapeutic relevance to the frequent ERα + /HER2-/PI3Kα-mutant subtype of breast cancer. The 3-drug combination targets ERα in combination with PI3Kα and cyclin-dependent kinase inhibitor 1 (p21). In addition, the 4-drug combination contains an inhibitor for poly (ADP-ribose) polymerase 1 (PARP1), which showed benefits in long-term treatments. Moreover, we validated the efficacy of the combinations in tamoxifen-resistant cell lines, patient-derived organoids, and xenograft experiments. Thus, we propose multidrug combinations that have the potential to overcome the standard issues of current monotherapies.

Correlations between single nucleotide polymorphisms in obsessive-compulsive disorder with the clinical features or response to therapy

Obsessive-compulsive disorder (OCD) is a debilitating neuropsychiatric disorder, in which the patient endures intrusive thoughts or is compelled to perform repetitive or ritualized actions. Many cases of OCD are considered to be familial or heritable in nature. It has been shown that a variety of internal and external risk factors are involved in the pathogenesis of OCD. Among the internal factors, genetic modifications play a critical role in the pathophysiological process. Despite many investigations performed to determine the candidate genes, the precise genetic factors involved in the disease remain largely undetermined. The present review summarizes the single nucleotide polymorphisms that have been proposed to be associated with OCD symptoms, early onset disease, neuroimaging results, and response to therapy. This information could help us to draw connections between genetics and OCD symptoms, better characterize OCD in individual patients, understand OCD prognosis, and design more targeted personalized treatment approaches.

Role of Estrogen Receptor-Positive/Negative Ratios in Regulating Breast Cancer

The alpha estrogen receptor (ERα) contributes to breast cancer progression and recent guidelines define ER positivity as ≥1% stained cells, and a few tumor tissues show no ERα expression at all or are at 100%. Although ER and aromatase inhibitors are widely used to treat hormone receptor-positive (HR+) breast cancer, their effect on tumor activity at different ERα levels remains unclear. Therefore, we investigated the role of ERα+/ERα− ratios in determining the ERα level. We used ERα stably transfected and wild-type MDA-MB-231 cells (MDA-MB-231^Trans−ER and MDA-MB-231^WT, respectively) as represented ER+ and ER− cells, respectively, and MCF-7 cells were the positive control. MDA-MB-231^Trans−ER and MDA-MB-231^WT cells were mixed and cocultured at a ratio of 0%, 20%, 40%, 70%, and 100%. Migration and invasion functions at different cell ratios were evaluated in vitro using the Transwell and scratch test. In a xenograft mouse model, the polarization of the tumor-associated (M2) macrophage and the expression of breast cancer gene 1 (BRCA1), human epidermal growth factor receptor 2 (HER2), vascular endothelial growth factor (VEGF), and tumor necrosis factor (TNF)-α were measured. The results showed that the cell invasion and migration were significantly higher at 40% and 70% than they were at other ratios. Additionally, in vivo, the 70% ERα+/ERα-ratio was a critical indicator of cell activity and cytokine expression. The highest M2 level and expression of VEGR, TNF-α, BRCA1, and HER2 were shown at a ratio of 70%. Moreover, the effects of ERα were not linear in breast cancer, indicating that the ERα status requires continuous monitoring during long-term endocrine treatment. These results indicate that during HR+ breast cancer treatment, the ERα+/ERα− ratio may be a useful predictor and should be evaluated further.

Estrogen Signaling Dictates Musculoskeletal Stem Cell Behavior: Sex Differences in Tissue Repair

Sexual dimorphisms in humans and other species exist in visually evident features such as body size and less apparent characteristics, including disease prevalence. Current research is adding to a growing understanding of sex differences in stem cell function and response to external stimuli, including sex hormones such as estrogens. These differences are proving significant and directly impact both the understanding of stem cell processes in tissue repair and the clinical implementation of stem cell therapies. Adult stem cells of the musculoskeletal system, including those used for development and repair of muscle, bone, cartilage, fibrocartilage, ligaments, and tendons, are no exception. Both in vitro and in vivo studies have found differences in stem cell number, proliferative and differentiation capabilities, and response to estrogen treatment between males and females of many species. Maintaining the stemness and reducing senescence of adult stem cells is an important topic with implications in regenerative therapy and aging. As such, this review discusses the effect of estrogens on musculoskeletal system stem cell response in multiple species and highlights the research gaps that still need to be addressed. The following evidence from investigations of sex-related phenotypes in adult progenitor and stem cells are pieces to the big puzzle of sex-related effects on aging and disease and critical information for both fundamental tissue repair and regeneration studies and safe and effective clinical use of stem cells. Impact Statement This review summarizes current knowledge of sex differences in and the effects of estrogen treatment on musculoskeletal stem cells in the context of tissue engineering. Specifically, it highlights the impact of sex on musculoskeletal stem cell function and ability to regenerate tissue. Furthermore, it discusses the varying effects of estrogen on stem cell properties, including proliferation and differentiation, important to tissue engineering. This review aims to highlight the potential impact of estrogens and the importance of performing sex comparative studies in the field of tissue engineering.

Estrogens revert neutrophil hyperplasia by inhibiting Hif1α-cMyb pathway in zebrafish myelodysplastic syndromes models

Myelodysplastic syndromes (MDS) are characterized by daunting genetic heterogeneity and a high risk of leukemic transformation, which presents great challenges for clinical treatment. To identify new chemicals for MDS, we screened a panel of FDA-approved drugs and verified the neutrophil hyperplasia inhibiting role of 17β-estradiol (E2, a natural estrogen) in several zebrafish MDS models (pu.1^G242D/G242D, irf8^Δ57Δ/57 and c-myb^hyper). However, the protective mechanism of estrogen in the development of hematological malignancies remains to be explored. Here, analyzing the role of E2 in the development of each hematopoietic lineage, we found that E2 exhibited a specific neutrophil inhibiting function. This neutrophil inhibitory function of E2 is attributed to its down-regulation of c-myb, which leads to accelerated apoptosis and decreased proliferation of neutrophils. We further showed that knockdown of hif1α could mimic the neutrophil inhibiting role of E2, and hif1α overexpression could reverse the protective function of E2. Collectively, our findings highlight the protective role of E2 on MDS by inhibiting hif1α-c-myb pathway, suggesting that E2 is a promising and effective drug for hematopoietic tumors associated with abnormal neutrophil hyperplasia.

Estrogeni e infiammazione

L’infiammazione è un processo essenziale per la vita, modulato da meccanismi immunoneuroendocrini. In questa Rassegna si analizza il ruolo degli estrogeni naturali umani (estradiolo, estrone, estriolo ed estetrolo) nella regolazione dell’infiammazione, facendo riferimento alla loro interazione con gli altri steroidi sessuali (progesterone e androgeni) nella modulazione di tale processo. L’infiammazione può essere fisiologica, quando è finalizzata (resolving), di breve durata, di intensità limitata e termina con restitutio ad integrum. È patologica quando perde tali caratteristiche diventando non finalizzata, non risolutiva (non resolving), di variabile intensità, con andamento cronico e progressiva distruzione tissutale. Durante la vita fertile della donna si manifestano tre eventi infiammatori fisiologici pertinenti alla sfera riproduttiva: l’ovulazione, la mestruazione e il parto. Tutti e tre sono strettamente correlati con le oscillazioni dei livelli di estrogeni, nonché del progesterone e degli androgeni. L’azione degli estrogeni nei confronti dell’infiammazione è molto articolata, in rapporto al tipo di estrogeno considerato, all’andamento dei suoi livelli plasmatici (fluttuante versus stabile) e al tipo di interazione con i recettori estrogenici, in particolare di tipo \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\alpha $\end{document}α e \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\beta $\end{document}β. Le fluttuazioni estrogeniche, in particolare dell’estradiolo, influiscono sulla presenza e l’attivazione delle varie classi di cellule immunitarie nell’endometrio e a livello sistemico. Accanto agli estrogeni, progesterone e androgeni rivestono un ruolo immunomodulatorio, con prevalenza anti-infiammatoria. La concisa descrizione delle complesse interazioni tra i diversi tipi di estrogeni e il sistema immunitario è stata fatta privilegiando gli aspetti più attinenti alla pratica clinica quotidiana dell’endocrinologo/a.

Sex Differences in Psychostimulant Abuse: Implications for Estrogen Receptors and Histone Deacetylases

Substance abuse is a chronic pathological disorder that negatively affects many health and neurological processes. A growing body of literature has revealed gender differences in substance use. Compared to men, women display distinct drug-use phenotypes accompanied by recovery and rehabilitation disparities. These observations have led to the notion that sex-dependent susceptibilities exist along the progression to addiction. Within this scope, neuroadaptations following psychostimulant exposure are thought to be distinct for each sex. This review summarizes clinical findings and animal research reporting sex differences in the subjective and behavioral responses to cocaine, methamphetamine, and nicotine. This discussion is followed by an examination of epigenetic and molecular alterations implicated in the addiction process. Special consideration is given to histone deacetylases and estrogen receptor-mediated gene expression.

The steroid hormone estriol (E3) regulates epigenetic programming of fetal mouse brain and reproductive tract

Background

Estriol (E3) is a steroid hormone formed only during pregnancy in primates including humans. Although E3 is synthesized at large amounts through a complex pathway involving the fetus and placenta, it is not required for the maintenance of pregnancy and has classically been considered virtually inactive due to associated very weak canonical estrogen signaling. However, estrogen exposure during pregnancy may have an effect on organs both within and outside the reproductive system, and compounds with binding affinity for estrogen receptors weaker than E3 have been found to impact reproductive organs and the brain. Here, we explore potential effects of E3 on fetal development using mouse as a model system.

Results

We administered E3 to pregnant mice, exposing the fetus to E3. Adult females exposed to E3 in utero (E3-mice) had increased fertility and superior pregnancy outcomes. Female and male E3-mice showed decreased anxiety and increased exploratory behavior. The expression levels and DNA methylation patterns of multiple genes in the uteri and brains of E3-mice were distinct from controls. E3 promoted complexing of estrogen receptors with several DNA/histone modifiers and their binding to target genes. E3 functions by driving epigenetic change, mediated through epigenetic modifier interactions with estrogen receptors rather than through canonical nuclear transcriptional activation.

Conclusions

We identify an unexpected functional role for E3 in fetal reproductive system and brain. We further identify a novel mechanism of estrogen action, through recruitment of epigenetic modifiers to estrogen receptors and their target genes, which is not correlated with the traditional view of estrogen potency.

2',3',4'-Trihydroxychalcone changes estrogen receptor α regulation of genes and breast cancer cell proliferation by a reprogramming mechanism

BACKGROUND

Menopausal hormone therapy (MHT) is recommended for only five years to treat vasomotor symptoms and vulvovaginal atrophy because of safety concerns with long-term treatment. We investigated the ability of 2',3',4'-trihydroxychalcone (2',3',4'-THC) to modulate estrogen receptor (ER)-mediated responses in order to find drug candidates that could potentially prevent the adverse effects of long-term MHT treatment.

METHODS

Transfection assays, real time-polymerase chain reaction, and microarrays were used to evaluate the effects of 2',3',4'-THC on gene regulation. Radioligand binding studies were used to determine if 2',3',4'-THC binds to ERα. Cell proliferation was examined in MCF-7 breast cancer cells by using growth curves and flow cytometry. Western blots were used to determine if 2',3',4'-THC alters the E2 activation of the MAPK pathway and degradation of ERα. Chromatin immunoprecipitation was used to measure ERα binding to genes.

RESULTS

The 2',3',4'-THC/E2 combination produced a synergistic activation with ERα on reporter and endogenous genes in human U2OS osteosarcoma cells. Microarrays identified 824 genes that we termed reprogrammed genes because they were not regulated in U2OS-ERα cells unless they were treated with 2',3',4'-THC and E2 at the same time. 2',3',4'-THC blocked the proliferation of MCF-7 cells by preventing the E2-induced activation of MAPK and c-MYC transcription. The antiproliferative mechanism of 2',3',4'-THC differs from selective estrogen receptor modulators (SERMs) because 2',3',4'-THC did not bind to the E2 binding site in ERα like SERMs.

CONCLUSION

Our study suggests that 2',3',4'-THC may represent a new class of ERα modulators that do not act as a direct agonists or antagonists. We consider 2',3',4'-THC to be a reprogramming compound, since it alters the activity of ERα on gene regulation and cell proliferation without competing with E2 for binding to ERα. The addition of a reprogramming drug to estrogens in MHT may offer a new strategy to overcome the adverse proliferative effects of estrogen in MHT by reprogramming ERα as opposed to an antagonist mechanism that involves blocking the binding of estrogen to ERα.

In Silico Screening of Marine Compounds as an Emerging and Promising Approach against Estrogen Receptor Alpha-Positive Breast Cancer

Presently, the majority of breast tumors are estrogen receptor (ER) positive. Breast cancer (BC) is defined by uncontrolled cell proliferation (CP) in breast tissue. BCs are caused by the overexpression of genes that promote CP in breast cells. The discovery of effective inhibitors is an excellent chemopreventive method. Our in silico approach analysis offers a pharmacoinformatics methodology for identifying lead molecules targeting cochaperone HSP90 and the epidermal growth factor receptors (EGFR) and human epidermal growth factor receptor 2 (HER2)/neu receptor. BC has been associated with the high expression of these targets. The use of drug-likeness filters aided in determining the therapeutic properties of possible lead compounds. In this study, docking-based virtual screening (VS) was performed. Database of about 450 cancer marine compounds was used. The X-ray-assisted structure of ERα with 4-OHT (PDB code: 3ERT) was chosen for 4-OHT. A docking-based virtual screening was performed on the dataset supplied using the molecular operating environment (MOE) dock application. The binding energy (BE) and explanation of the protein inhibitor interaction (PII) are crucial findings for future both in terms of dry or wet lab research. The GBVI/WAS binding-free energy assessment (in kcal/mol) scores were used to grade the compounds. Compounds with a BE of less than -9.500 kcal/mol were deemed to be the most effective inhibitors. For further analysis, the top seven structurally diverse scaffolds were selected. Seven marine compounds exhibited the best docking score, which validates them to be potent anti-BC compounds. These compounds' bioactive potential and prospective drug-likeness profile make them promising leads for further experimental research.

Estrogens and Androgens in Plants: The Last 20 Years of Studies

Although the only known steroid hormones in plants are brassinosteroids, interestingly, mammalian steroid hormones such as androgens or estrogens are also part of the plant metabolic profile. This presented review is focused on the progress that has been made in this matter during the last two decades. The presence of testosterone, 17β-estradiol, and other androgens/estrogens in plants (particularly those that can be measured using more advanced techniques) is described. The physiological activity of androgens and estrogens, especially in plants’ stress response, are discussed, together with some possible mechanisms of their action. The current knowledge indicates that although androgens and estrogens do not have the status of hormones in plants, they are physiologically active and can serve as regulators that support the activity of classic hormones in (1) regulating the various processes connected with plant growth and development and (2) the interaction of plants with their environment.

Estradiol promotes cell survival and induces Greb1 expression in granulosa cell tumors of the ovary through an ERα-dependent mechanism

Granulosa cell tumor (GCT) is a form of ovarian tumor characterized by its tendency to recur years after surgical ablation. Little is known on the mechanisms involved in GCT development and progression. GCTs can produce estradiol (E2), but whether this hormone could play a role in this cancer through its nuclear receptors, i.e., ERα and ERβ, remains unknown. Here, we addressed this issue by cell-based and molecular studies on human GCTs and GCT cell lines. Importantly, we observed that E2 significantly increased the growth of GCT cells by promoting cell survival. The use of selective agonists of each type of receptor, together with Esr1 (ERα) or Esr2 (ERβ)-deleted GCT cells revealed that E2 mediated its effects through ERα-dependent genomic mechanisms and ERβ/ERα-dependent extra-nuclear mechanisms. Notably, the expression of Greb1, a prototypical ER target gene, was dose-dependently up-regulated by E2 specifically through ERα in GCT cells. Accordingly, using GCTs from patients, we found that GREB1 mRNA abundance was positively correlated to intra-tumoral E2 concentrations. Tissue microarrays analyses showed that there were various combinations of ER expression in primary and recurrent GCTs, and that ERα expression persisted only in combination with ERβ in ~40% of recurrent tumors. Altogether, this study demonstrates that E2 can promote the progression of GCTs, with a clear dependence on ERα. In addition to demonstrating that GCTs can be classified as a hormone-related cancer, our results also highlight that the nature of ER forms present in recurrent GCTs could underlie the variable efficiency of endocrine therapies. This article is protected by copyright. All rights reserved.

The extra-nuclear interactome of the estrogen receptors: implications for physiological functions

Over the last decades, a great body of evidence has defined a novel view of the cellular mechanism of action of the steroid hormone 17β-estradiol (E2) through its estrogen receptors (i.e., ERα and ERβ). It is now clear that the E2-activated ERs work both as transcription factors and extra-nuclear plasma membrane-localized receptors. The activation of a plethora of signal transduction cascades follows the E2-dependent engagement of plasma membrane-localized ERs and is required for the coordination of gene expression, which ultimately controls the occurrence of the pleiotropic effects of E2. The definition of the molecular mechanisms by which the ERs locate at the cell surface (i.e., palmitoylation and protein association) determined the quest for understanding the specificity of the extra-nuclear E2 signaling. The use of mice models lacking the plasma membrane ERα localization unveiled that the extra-nuclear E2 signaling is operational in vivo but tissue-specific. However, the underlying molecular details for such ERs signaling diversity in the perspective of the E2 physiological functions in the different cellular contexts are still not understood. Therefore, to gain insights into the tissue specificity of the extra-nuclear E2 signaling to physiological functions, here we reviewed the known ERs extra-nuclear interactors and tried to extrapolate from available databases the ERα and ERβ extra-nuclear interactomes. Based on literature data, it is possible to conclude that by specifically binding to extra-nuclear localized proteins in different sub-cellular compartments, the ERs fine-tune their molecular activities. Moreover, we report that the context-dependent diversity of the ERs-mediated extra-nuclear E2 actions can be ascribed to the great flexibility of the physical structures of ERs and the spatial-temporal organization of the logistics of the cells (i.e., the endocytic compartments). Finally, we provide lists of proteins belonging to the potential ERα and ERβ extra-nuclear interactomes and propose that the systematic experimental definition of the ERs extra-nuclear interactomes in different tissues represents the next step for the research in the ERs field. Such characterization will be fundamental for the identification of novel druggable targets for the innovative treatment of ERs-related diseases.

Positive Regulation of Estrogen Receptor Alpha in Breast Tumorigenesis

Estrogen receptor alpha (ERα, NR3A1) contributes through its expression in different tissues to a spectrum of physiological processes, including reproductive system development and physiology, bone mass maintenance, as well as cardiovascular and central nervous system functions. It is also one of the main drivers of tumorigenesis in breast and uterine cancer and can be targeted by several types of hormonal therapies. ERα is expressed in a subset of luminal cells corresponding to less than 10% of normal mammary epithelial cells and in over 70% of breast tumors (ER+ tumors), but the basis for its selective expression in normal or cancer tissues remains incompletely understood. The mapping of alternative promoters and regulatory elements has delineated the complex genomic structure of the ESR1 gene and shed light on the mechanistic basis for the tissue-specific regulation of ESR1 expression. However, much remains to be uncovered to better understand how ESR1 expression is regulated in breast cancer. This review recapitulates the current body of knowledge on the structure of the ESR1 gene and the complex mechanisms controlling its expression in breast tumors. In particular, we discuss the impact of genetic alterations, chromatin modifications, and enhanced expression of other luminal transcription regulators on ESR1 expression in tumor cells.

Sex Differences and Regulatory Actions of Estrogen in Cardiovascular System

Great progress has been made in the understanding of the pathophysiology of cardiovascular diseases (CVDs), and this has improved the prevention and prognosis of CVDs. However, while sex differences in CVDs have been well documented and studied for decades, their full extent remains unclear. Results of the latest clinical studies provide strong evidence of sex differences in the efficacy of drug treatment for heart failure, thereby possibly providing new mechanistic insights into sex differences in CVDs. In this review, we discuss the significance of sex differences, as rediscovered by recent studies, in the pathogenesis of CVDs. First, we provide an overview of the results of clinical trials to date regarding sex differences and hormone replacement therapy. Then, we discuss the role of sex differences in the maintenance and disruption of cardiovascular tissue homeostasis.

Beyond the X Factor: Relevance of Sex Hormones in NAFLD Pathophysiology

Non-alcoholic fatty liver disease (NAFLD) is a major health issue worldwide, being frequently associated with obesity, unbalanced dietary regimens, and reduced physical activity. Despite their greater adiposity and reduced physical activity, women show a lower risk of developing NAFLD in comparison to men, likely a consequence of a sex-specific regulation of liver metabolism. In the liver, sex differences in the uptake, synthesis, oxidation, deposition, and mobilization of lipids, as well as in the regulation of inflammation, are associated with differences in NAFLD prevalence and progression between men and women. Given the major role of sex hormones in driving hepatic sexual dimorphism, this review will focus on the role of sex hormones and their signaling in the regulation of hepatic metabolism and in the molecular mechanisms triggering NAFLD development and progression.

Role of estrogen receptor coregulators in endocrine resistant breast cancer

Breast cancer (BC) is the most ubiquitous cancer in women. Approximately 70–80% of BC diagnoses are positive for estrogen receptor (ER) alpha (ERα). The steroid hormone estrogen [17β-estradiol (E2)] plays a vital role both in the initiation and progression of BC. The E2-ERα mediated actions involve genomic signaling and non-genomic signaling. The specificity and magnitude of ERα signaling are mediated by interactions between ERα and several coregulator proteins called coactivators or corepressors. Alterations in the levels of coregulators are common during BC progression and they enhance ligand-dependent and ligand-independent ERα signaling which drives BC growth, progression, and endocrine therapy resistance. Many ERα coregulator proteins function as scaffolding proteins and some have intrinsic or associated enzymatic activities, thus the targeting of coregulators for blocking BC progression is a challenging task. Emerging data from in vitro and in vivo studies suggest that targeting coregulators to inhibit BC progression to therapy resistance is feasible. This review explores the current state of ERα coregulator signaling and the utility of targeting the ERα coregulator axis in treating advanced BC.

The effect of dehydroepiandrosterone (DHEA) supplementation on estradiol levels in women: A dose-response and meta-analysis of randomized clinical trials

Estradiol, an estrogen steroid hormone, serves as the dominant female hormone and its levels fluctuate during lifetime. In women, after the menopause, all estrogens and almost all androgens are locally developed in the peripheral tissues from dehydroepiandrosterone (DHEA). However, the effect of DHEA supplementation on estradiol levels in women is unclear as previously published data has resulted in conflicting findings. Thus, we conducted the present dose-response meta-analysis of randomized controlled trials (RCTs) evaluating the influence of DHEA on estradiol concentrations in women. The PubMed/Medline, Embase, Web of Science and Scopus databases were systematically searched for articles published on this topic until May 10, 2021. No time or language restrictions were applied. The data were expressed as weighted mean differences (WMDs) and 95% confidence intervals (CI), and a P-value of less than 0.05 was considered to be statistically significant. The pooled results were obtained using the generic inverse of variance method with a random effects model. A total of 21 arms, including 1223 participants (case = 610, and control = 613), reported estradiol concentrations as an outcome measure. The overall results demonstrated that estradiol significantly increased following the administration of DHEA (WMD: 7.02 pg/mL, 95% CI: 5.43, 8.62, P = 0.000). The stratified analyses revealed that the elevation of estradiol concentrations was more pronounced in subjects aged ≥60 years old (WMD: 8.56 pg/mL, 95% CI: 6.97, 10.16, I² = 94%) and in those receiving DHEA supplements for ≥26 weeks (WMD: 7.30 pg/mL, 95% CI: 6.28, 8.32, I² = 61%). Moreover, estradiol levels increased significantly with DHEA dosages of 50 mg/day (WMD: 7.75 pg/mL, 95% CI: 9.12, 9.39, I² = 94%) and when DHEA was prescribed to postmenopausal women (WMD: 7.61 pg/mL, 95% CI: 5.97, 9.24, I² = 93%). This meta-analysis has provided a comprehensive overview of the effects of DHEA administration on circulating estradiol levels, far beyond the available evidence from different RCTs. Subsequent subgroup analyses revealed that postmenopausal women, females aged 60 years and above, those on DHEA dosages of 50 mg/day and those receiving DHEA for ≥26 weeks registered a more pronounced elevation of the circulating estradiol levels.

Age and/or postmenopausal status as risk factors for pelvic organ prolapse development: systematic review with meta-analysis

INTRODUCTION AND HYPOTHESIS

Age is named as a risk factor for pelvic organ prolapse (POP), despite not being the primary outcome for many observational studies. Postmenopausal status is another associated factor but has many confounders. We aimed to systematically review the role of age and/or postmenopausal status in POP development.

METHODS

Systematic review addressing age and hormones, more specifically by postmenopausal status, from inception to March 2020 in four databases (PubMed, Embase, WOS, Cochrane Library). Quality of evidence was classified by the ROBINS-I classification for non-randomized studies. Experimental studies, animal studies, studies linking age with recurrent POP and case series were excluded. Effect estimates were collected from adjusted odds ratio plus 95% confidence intervals. Significance level was 5%. A discussion exploring mechanistic factors was also included.

RESULTS

Nineteen studies (11 cross sectional, 6 cohort and 2 case control) were included for quantitative analysis. Only two studies presented a low overall risk of bias for age; most of the domains were of moderate risk. Every additional year was responsible for a 10% increase in the risk to develop POP (OR = 1.102 [1.021-1.190]; i² = 80%, random analysis, p = 0.012). This trend was confirmed when age was dichotomized into a cutoff of 35 (p = 0.035) and 50 (p < 0.001) years. Although an increase in the risk for POP was noted in postmenopausal women, this did not reach statistical significance (OR = 2.080 [0.927-4.668], i² = 0%, p = 0.076).

CONCLUSION

Age is a risk factor for POP; postmenopausal status was not statistically associated with POP, prompting the need for further studies addressing this factor.

Estradiol-induced inhibition of endoplasmic reticulum stress normalizes splenic CD4 + T lymphocytes following hemorrhagic shock

The aim is to investigate that 17β-estradiol (E2)/estrogen receptors (ERs) activation normalizes splenic CD4 + T lymphocytes proliferation and cytokine production through inhibition of endoplasmic reticulum stress (ERS) following hemorrhage. The results showed that hemorrhagic shock (hemorrhage through femoral artery, 38–42 mmHg for 90 min followed by resuscitation of 30 min and subsequent observation period of 180 min) decreased the CD4⁺ T lymphocytes proliferation and cytokine production after isolation and incubation with Concanavalin A (5 μg/mL) for 48 h, induced the splenic injury with evidences of missed contours of the white pulp, irregular cellular structure, and typical inflammatory cell infiltration, upregulated the expressions of ERS biomarkers 78 kDa glucose-regulated protein (GRP78) and activating transcription factor 6 (ATF6). Either E2, ER-α agonist propyl pyrazole triol (PPT) or ERS inhibitor 4-Phenylbutyric acid administration normalized these parameters, while ER-β agonist diarylpropionitrile administration had no effect. In contrast, administrations of either ERs antagonist ICI 182,780 or G15 abolished the salutary effects of E2. Likewise, ERS inducer tunicamycin induced an adverse effect similarly to that of hemorrhagic shock in sham rats, and aggravated shock-induced effects, also abolished the beneficial effects of E2 and PPT, respectively. Together, the data suggest that E2 produces salutary effects on CD4⁺ T lymphocytes function, and these effects are mediated by ER-α and GPR30, but not ER-β, and associated with the attenuation of hemorrhagic shock-induced ERS.

CNS genomic profiling in the mouse chronic social stress model implicates a novel category of candidate genes integrating affective pathogenesis

Despite high prevalence, medical impact and societal burden, anxiety, depression and other affective disorders remain poorly understood and treated. Clinical complexity and polygenic nature complicate their analyses, often revealing genetic overlap and cross-disorder heritability. However, the interplay or overlaps between disordered phenotypes can also be based on shared molecular pathways and 'crosstalk' mechanisms, which themselves may be genetically determined. We have earlier predicted (Kalueff et al., 2014) a new class of 'interlinking' brain genes that do not affect the disordered phenotypes per se, but can instead specifically determine their interrelatedness. To test this hypothesis experimentally, here we applied a well-established rodent chronic social defeat stress model, known to progress in C57BL/6J mice from the Anxiety-like stage on Day 10 to Depression-like stage on Day 20. The present study analyzed mouse whole-genome expression in the prefrontal cortex and hippocampus during the Day 10, the Transitional (Day 15) and Day 20 stages in this model. Our main question here was whether a putative the Transitional stage (Day 15) would reveal distinct characteristic genomic responses from Days 10 and 20 of the model, thus reflecting unique molecular events underlining the transformation or switch from anxiety to depression pathogenesis. Overall, while in the Day 10 (Anxiety) group both brain regions showed major genomic alterations in various neurotransmitter signaling pathways, the Day 15 (Transitional) group revealed uniquely downregulated astrocyte-related genes, and the Day 20 (Depression) group demonstrated multiple downregulated genes of cell adhesion, inflammation and ion transport pathways. Together, these results reveal a complex temporal dynamics of mouse affective phenotypes as they develop. Our genomic profiling findings provide first experimental support to the idea that novel brain genes (activated here only during the Transitional stage) may uniquely integrate anxiety and depression pathogenesis and, hence, determine the progression from one pathological state to another. This concept can potentially be extended to other brain conditions as well. This preclinical study also further implicates cilial and astrocytal mechanisms in the pathogenesis of affective disorders.

Expression and clinical implications of estrogen receptors in thoracic malignancies: a narrative review

Thoracic malignancies represent a significant global health burden with incidence and mortality increasing year by year. Thoracic cancer prognosis and treatment options depend on several factors, including the type and size of the tumor, its location, and the overall health status of patients. Gender represents an important prognostic variable in thoracic malignancies. One of the greatest biological differences between women and men is the presence of female sex hormones, and an increasing number of studies suggest that estrogens may play either a causative or a protective role in thoracic malignancies. Over the past 60 years since the discovery of the first nuclear estrogen receptor (ER) isoform α and the almost 20 years since the discovery of the second estrogen receptor, ERβ, different mechanisms governing estrogen action have been identified and characterized. This literature review reports the published data regarding the expression and function of ERs in different thoracic malignancies and discuss sex disparity in clinical outcomes. From this analysis emerges that further efforts are warranted to better elucidate the role of sex hormones in thoracic malignancies, and to reduce disparities in care between genders. Understanding the mechanisms by which gender-related differences can affect and interfere with the onset and evolution of thoracic malignancies and impact on response to therapies could help to improve the knowledge needed to develop increasingly personalized and targeted treatments.

Relevance of the Isoflavone Absorption and Testicular Function: A Systematic Review of Preclinical Evidence

Isoflavone is a phytoestrogen found in different types of food that can act as endocrine disrupters leading to testicular dysfunction. Currently, fragmented data on the action of this compound in the testicles make it difficult to assess its effects to define a safe dose. Thus, we systematically reviewed the preclinical evidence of the impact of isoflavone on testicular function. We also determined which form (aglycones or glycosylated) was the most used, which allowed us to understand the main biological processes involved in testicular function after isoflavone exposure. This systematic review was carried out according to the PRISMA guidelines using a structured search on the biomedical databases MEDLINE (PubMed), Scopus, and Web of Science, recovering and analyzing 22 original studies. The bias analysis and the quality of the studies were assessed by the criteria described in the risk of bias tool developed by SYRCLE (Systematic Review Centre for Laboratory Animal Experimentation). The aglycones and glycosylated isoflavones proved to be harmful to the reproductive health, and the glycosylates at doses of 50, 100, 146, 200, 300, 500, and 600 mg/kg, in addition to 190 and 1000 mg/L, appear to be even more harmful. The main testicular pathologies resulting from the use of isoflavones are associated with Leydig cells resulting from changes in molecular functions and cellular components. The most used isoflavone to evaluate testicular changes was the genistein/daidzein conjugate. The consumption of high doses of isoflavones promotes changes in the functioning of Leydig cells, inducing testicular changes and leading to infertility in murine models.

Estrogen Receptor Beta: The Promising Biomarker and Potential Target in Metastases

The discovery of the Estrogen Receptor Beta (ERβ) in 1996 opened new perspectives in the diagnostics and therapy of different types of cancer. Here, we present a review of the present research knowledge about its role in endocrine-related cancers: breast, prostate, and thyroid, and colorectal cancers. We also discuss the reasons for the controversy of its role in carcinogenesis and why it is still not in use as a biomarker in clinical practice. Given that the diagnostics and therapy would benefit from the introduction of new biomarkers, we suggest ways to overcome the contradictions in elucidating the role of ERβ.

Sex Hormones in Lymphedema

Simple Summary

Lymphedema is a life-long disease that affects a large number of patients treated for breast-, gynecological-, and urologic cancers in Western countries. Given that hormone levels are strongly modified in these conditions, and that patients widely undergo through hormone therapy, it is tempting to speculate that hormones might be key regulators in the maintenance of lymphedema. Despite an obvious prevalence for women, the role of sex hormones and gender has been poorly investigated in this pathology. This review aims to decipher how sex hormones interact with lymphatic vessels and whether hormone therapy could participate in lymphedema development.

Abstract

Lymphedema is a disorder of the lymphatic vascular system characterized by impaired lymphatic return resulting in swelling of the extremities and accumulation of undrained interstitial fluid/lymph that results in fibrosis and adipose tissue deposition in the limb. Whereas it is clearly established that primary lymphedema is sex-linked with an average ratio of one male for three females, the role of female hormones, in particular estrogens, has been poorly explored. In addition, secondary lymphedema in Western countries affects mainly women who developed the pathology after breast cancer and undergo through hormone therapy up to five years after cancer surgery. Although lymphadenectomy is identified as a trigger factor, the effect of co-morbidities associated to lymphedema remains elusive, in particular, estrogen receptor antagonists or aromatase inhibitors. In addition, the role of sex hormones and gender has been poorly investigated in the etiology of the pathology. Therefore, this review aims to recapitulate the effect of sex hormones on the physiology of the lymphatic system and to investigate whetherhormone therapy could promote a lymphatic dysfunction leading to lymphedema.

The role of Gα protein signaling in the membrane estrogen receptor-mediated signaling

Estrogens exert rapid, extranuclear effects by their action on the plasma membrane estrogen receptors (mERs). Gα protein associated with the cell membrane is involved in many important processes regulated by estrogens. However, the Gα's role in the mER-mediated signaling and the signaling pathways involved are poorly understood. This review aims to outline the Gα's role in the mER-mediated signaling. Immunoblotting, immunofluorescence, co-immunoprecipitation, and RNA interference were carried out using vascular endothelial cells (ECs) and human breast carcinoma cell lines as experimental models. Electrophysiology and immunocytochemistry were carried out using guinea pigs as animal models. Recent advances suggest that the signaling of mERα through Gα is required for vascular EC migration or endothelial H₂S release, while Gα₁₃ is involved in estrogen-induced breast cancer cell invasion. Besides, the Gα_q-coupled PLC-PKC-PKA pathway is critical for the neural regulation of energy homeostasis. This review summarizes the contributions of Gα to mER-mediated signaling, including cardiovascular protection, breast cancer metastasis, neural regulation of homeostatic functions, and osteogenesis.

Arginine site 264 in murine estrogen receptor-α is dispensable for the regulation of the skeleton

Mutation of arginine 264 in ERα has been shown to abrogate rapid membrane ERα-mediated endothelial effects. Our novel finding that mutation of R264 is dispensable for ERα-mediated skeletal effects supports the concept that R264 determines tissue specificity of ERα. Estrogen protects against bone loss but is not a suitable treatment due to adverse effects in other tissues. Therefore, increased knowledge regarding estrogen signaling in estrogen-responsive tissues is warranted to aid the development of bone-specific estrogen treatments. Estrogen receptor-α (ERα), the main mediator of estrogenic effects in bone, is widely subjected to posttranslational modifications (PTMs). In vitro studies have shown that methylation at site R260 in the human ERα affects receptor localization and intracellular signaling. The corresponding amino acid R264 in murine ERα has been shown to have a functional role in endothelium in vivo, although the methylation of R264 in the murine gene is yet to be empirically demonstrated. The aim of this study was to investigate whether R264 in ERα is involved in the regulation of the skeleton in vivo. Dual-energy X-ray absorptiometry (DEXA) analysis at 3, 6, 9, and 12 mo of age showed no differences in total body areal bone mineral density (BMD) between R264A and wild type (WT) in either female or male mice. Furthermore, analyses using computed tomography (CT) demonstrated that trabecular bone mass in tibia and vertebra and cortical thickness in tibia were similar between R264A and WT mice. In addition, R264A females displayed a normal estrogen treatment response in trabecular bone mass as well as in cortical thickness. Furthermore, uterus, thymus, and adipose tissue responded similarly in R264A and WT female mice after estrogen treatment. In conclusion, our novel finding that mutation of R264 in ERα does not affect the regulation of the skeleton, together with the known role of R264 for ERα-mediated endothelial effects, supports the concept that R264 determines tissue specificity of ERα.NEW & NOTEWORTHY Mutation of arginine 264 in ERα has been shown to abrogate rapid membrane ERα-mediated endothelial effects. Our novel finding that mutation of R264 is dispensable for ERα-mediated skeletal effects supports the concept that R264 determines tissue specificity of ERα.

Hormone Receptor Loss in Breast Cancer: Molecular Mechanisms, Clinical Settings, and Therapeutic Implications

Hormone receptor-positive breast cancer (HR+ BC) accounts for approximately 75% of new BC diagnoses. Despite the undisputable progresses obtained in the treatment of HR+ BC in recent years, primary or acquired resistance to endocrine therapies still represents a clinically relevant issue, and is largely responsible for disease recurrence after curative surgery, as well as for disease progression in the metastatic setting. Among the mechanisms causing primary or acquired resistance to endocrine therapies is the loss of estrogen/progesterone receptor expression, which could make BC cells independent of estrogen stimulation and, consequently, resistant to estrogen deprivation or the pharmacological inhibition of estrogen receptors. This review aims at discussing the molecular mechanisms and the clinical implications of HR loss as a result of the therapies used in the neoadjuvant setting or for the treatment of advanced disease in HR+ BC patients.

Role of hormone receptors and HER2 as prospective molecular markers for breast cancer: An update

This review provides an updated account on the current methods, principles and mechanism of action of therapies for the detection of molecular markers of therapeutic importance in the prognosis of breast cancer progression and recurrence, which includes estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor2 (HER2). Indeed, hormone-receptors namely, ER, PR, proto-oncogene HER2 are the basic molecular markers that are recognized and established prognostic factors and predictors of response, for therapeutic practice. These markers can be detected by using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), which are established, faster and cost effective detection methods. These molecular markers along with clinicopathological prognostic parameters give the best prediction of the prognosis of cancer recurrence and progress. Finally, hormone receptors and HER2 as molecular markers are of prime therapeutic importance and have the capability to take part in future drug development techniques.

17β-estradiol binding to ERα promotes the progression of prolactinoma through estrogen-response element-induced CaBP-9k up-regulation

17β-estradiol (E2) is considered to be an important instigator of prolactinoma, and can positively regulate the expression of calbindin-D9k (CaBP-9k) which contains an estrogen responsive element (ERE) via estrogen receptors (ERs). However, the detailed mechanism of E2 in promoting CaBP-9k expression and their roles in prolactinoma progression remain unclear. Here, we aimed to characterize it. The luciferase gene reporter assay with luc-ERE transfection showed that E2 treatment significantly enhanced the transcriptional level of CaBP-9k, whereas CaBP-9k activity was reduced when GH3 and MMQ cells were treated with AZD9496, an antagonist of ERα. E2 treatment increased the protein expressions of CaBP-9k and ERα but not ERβ, whereas this effect was also abolished when cells were treated with AZD9496. Besides, immunoprecipitation (IP) and immunofluorescence assays demonstrated that CaBP-9k could directly interact with ERα not ERβ, and Chromatin IP (ChIP) assay showed that ERα could bind to ERE of the CaBP-9k promoter. Moreover, cell counting kit-8 (CCK-8) and flow cytometry assays showed that E2 treatment significantly enhanced cell viability and inhibited cell apoptosis, but these effects were all abolished when ERα was down-regulated by short hairpin RNA (shRNA) or inhibited by AZD9496, as well as CaBP-9K suppression in both GH3 and MMQ cell lines. Taken together, these findings indicated that E2 stimulation promoted prolactin cell proliferation and inhibited cell apoptosis through ERα-induced CaBP-9k up-regulation, which then accelerated the advanced progression of prolactinoma.

Transportin-2 plays a critical role in nucleocytoplasmic shuttling of oestrogen receptor-α

Oestrogen receptor-α (ERα) shuttles continuously between the nucleus and the cytoplasm, and functions as an oestrogen-dependent transcription factor in the nucleus and as an active mediator of signalling pathways, such as phosphatidylinositol 3-kinase (PI3K)/AKT, in the cytoplasm. However, little is known regarding the mechanism of ERα nucleocytoplasmic shuttling. In this study, we found that ERα is transported into the nucleus by importin-α/β1. Furthermore, we found that Transportin-2 (TNPO2) is involved in 17β-oestradiol (E2)-dependent cytoplasmic localisation of ERα. Interestingly, it was found that TNPO2 does not mediate nuclear export, but rather is involved in the cytoplasmic retention of ERα via the proline/tyrosine (PY) motifs. Moreover, we found that TNPO2 competitively binds to the basic nuclear localisation signal (NLS) of ERα with importin-α to inhibit importin-α/β-dependent ERα nuclear import. Finally, we confirmed that TNPO2 knockdown enhances the nuclear localisation of wild-type ERα and reduces PI3K/AKT phosphorylation in the presence of E2. These results reveal that TNPO2 regulates nucleocytoplasmic shuttling and cytoplasmic retention of ERα, so that ERα has precise functions depending on the stimulation.

Synthesis and evaluation of 17α-triazolyl and 9α-cyano derivatives of estradiol

A variety of 17α-triazolyl and 9α-cyano derivatives of estradiol were prepared and evaluated for binding to human ERβ in both a TR-FRET assay, as well as ERβ and ERα agonism in cell-based functional assays. 9α-Cyanoestradiol (5) was nearly equipotent as estradiol as an agonist for both ERβ and ERα. The potency of the 17α-triazolylestradiol analogs is considerably more variable and depends on the nature of the 4-substituent of the triazole ring. While rigid protein docking simulations exhibited significant steric clashing, induced fit docking providing more protein flexibility revealed that the triazole linker of analogs 2d and 2e extends outside of the traditional ligand binding domain with the benzene ring located in the loop connecting helix 11 to helix 12.

Perspectives on the Role of Non-Coding RNAs in the Regulation of Expression and Function of the Estrogen Receptor

Estrogen receptors (ERs) comprise several nuclear and membrane-bound receptors with different tissue-specific functions. ERα and ERβ are two nuclear members of this family, whereas G protein-coupled estrogen receptor (GPER), ER-X, and Gq-coupled membrane estrogen receptor (Gq-mER) are membrane-bound G protein-coupled proteins. ERα participates in the development and function of several body organs such as the reproductive system, brain, heart and musculoskeletal systems. ERβ has a highly tissue-specific expression pattern, particularly in the female reproductive system, and exerts tumor-suppressive roles in some tissues. Recent studies have revealed functional links between both nuclear and membrane-bound ERs and non-coding RNAs. Several oncogenic lncRNAs and miRNAs have been shown to exert their effects through the modulation of the expression of ERs. Moreover, treatment with estradiol has been shown to alter the malignant behavior of cancer cells through functional axes composed of non-coding RNAs and ERs. The interaction between ERs and non-coding RNAs has functional relevance in several human pathologies associated with estrogen regulation, such as cancers, intervertebral disc degeneration, coronary heart disease and diabetes. In the current review, we summarize scientific literature on the role of miRNAs and lncRNAs on ER-associated signaling and related disorders.

Transforming growth factor-β1 in intrauterine adhesion

Intrauterine adhesion (IUA), led by trauma to the basal layer, can prevent the endometrium from growing, resulting in complications in females, such as infertility and amenorrhea. Transforming growth factor-β1 (TGF-β1) plays a crucial role in inducing and promoting the differentiation and proliferation of mesenchymal cells, in the secretion of extracellular matrix-associated components, and is a major cytokine in initiating and terminating tissue repair downstream of the TGF-β/Smad signaling pathway. Some evidence supports that TGF-β1 is closely associated with the occurrence and development of IUA, and is regarded as an early risk factor of disease recurrence. Furthermore, the role of TGF-β1 has been demonstrated to be potentially regulated by a variety of cytokines, hormones, enzymes, and microRNAs. This review provides an overview of the expression, function, and regulation of TGF-β1 in IUA, with a brief discussion and perspectives on its future clinical implications on the diagnosis and treatment of IUA.