Loss of ERbeta expression as a common step in estrogen-dependent tumor progression

Targeting estrogen metabolism in high-grade serous ovarian cancer shows promise to overcome platinum resistance

The high mortality rate due to chemoresistance in patients with high-grade ovarian cancer (HGSOC) emphasizes the urgent need to determine optimal treatment strategies for advanced and recurrent cases. Our study investigates the interplay between estrogens and chemoresistance in HGSOC and shows clear differences between platinum-sensitive and -resistant tumors. Through comprehensive transcriptome analyzes, we uncover differences in the expression of genes of estrogen biosynthesis, metabolism, transport and action underlying platinum resistance in different tissues of HGSOC subtypes and in six HGSOC cell lines. Furthermore, we identify genes involved in estrogen biosynthesis and metabolism as prognostic biomarkers for HGSOC. Additionally, our study elucidates different patterns of estrogen formation/metabolism and their effects on cell proliferation between six HGSOC cell lines with different platinum sensitivity. These results emphasize the dynamic interplay between estrogens and HGSOC chemoresistance. In particular, targeting the activity of steroid sulfatase (STS) proves to be a promising therapeutic approach with potential efficacy in limiting estrogen-driven cell proliferation. Our study reveals potential prognostic markers as well as identifies novel therapeutic targets that show promise for overcoming resistance and improving treatment outcomes in HGSOC.

Anti-cancer mechanisms of natural isoflavones against melanoma

The incidence of skin-related neoplasms has generally increased in recent years. Melanoma arises from malignant mutations in melanocytes in the basal layer of the epidermis and is a fatal skin cancer that seriously threatens human health. Isoflavones are polyphenolic compounds widely present in legumes and have drawn scientists' attention, because they have good efficacy against a variety of cancers, including melanoma, without significant toxic side effects and resistance. In this review article, we summarize the research progress of isoflavones in melanoma, including anti-melanoma roles and mechanisms of isoflavones via inhibition of tyrosinase activity, melanogenesis, melanoma cell growth, invasion of melanoma cells, and induction of apoptosis in melanoma cells. This information is important for the prevention, clinical treatment, and prognosis and survival of melanoma.

Endometriosis-Associated Ovarian Cancer: From Molecular Pathologies to Clinical Relevance

Endometriosis is a chronic condition affecting reproductive-aged women, characterized by the growth of ectopic endometrial tissue. Despite being benign, endometriosis is associated with an increased risk of certain cancers, including endometriosis-associated ovarian cancer (EAOC). Ovarian cancer is rare, but more common in women with endometriosis, particularly endometrioid and clear-cell carcinomas. Factors such as hormonal imbalance, reproductive history, environmental exposures, and genetic predisposition contribute to the malignant transformation of endometriosis. Thus, understanding potential risk factors causing malignancy is crucial. Over the past few decades, various genetic mutations, microRNAs, as well as tumor microenvironmental factors have been identified, impacting pathways like PI3K/AKT/mTOR, DNA repair mechanisms, oxidative stress, and inflammation. Thus, this review aims to summarize molecular studies involved in EAOC pathogenesis as potential therapeutic targets. However, further research is needed to better understand the molecular and environmental factors driving EAOC development, to target the susceptibility of endometriotic lesions to malignant progression, and to identify effective therapeutic strategies.

Potent Estrogen Receptor β Agonists with Inhibitory Activity In Vitro , Fail to Suppress Xenografts of Endocrine-Resistant Cyclin-dependent Kinase 4/6 inhibitor-Resistant Breast Cancer Cells

Objective

Seventy percent of newly diagnosed breast cancers are estrogen receptor-α positive and HER2/neu negative [1]. First-line treatments incorporate endocrine therapy and cyclin-dependent kinase 4/6 inhibitors [2]. However, therapy resistance occurs in most patients [3-5]. Hence, there is an urgent need for effective second-line treatments. We previously showed that the potent estrogen receptor-β agonists, OSU-ERb-12 and LY500307, synergized with the selective estrogen receptor modulator, tamoxifen, in vitro. Furthermore, we showed that these compounds inhibited endocrine-resistant and cyclin-dependent kinase 4/6-inhibitor-resistant estrogen receptor α-positive cell lines in vitro [6]. Here, we used fulvestrant- and abemaciclib-resistant T47D-derived cell line xenografts to determine the efficacy of the combination of OSU-ERb-12 and LY500307 with tamoxifen in vivo.

Results

Despite efficacy in vitro, treatments failed to reduce xenograft tumor volumes. Hence, we conclude that this treatment strategy lacks direct cancer cell-intrinsic cytotoxic efficacy in vivo.

New mode of action of curcumin on prostate cancer cells: Modulation of endoplasmic reticulum-associated degradation mechanism and estrogenic signaling

Prostate cancer is leading to cancer-related mortality in numerous men each year worldwide. While there are several treatment options, acquired drug resistance mostly limits the success of treatments. Therefore, there is a need for the development of innovative treatments. Curcumin is one of the bioactive polyphenolic ingredients identified in turmeric and has numerous biological activities, such as anti-inflammatory and anticancer. In the present study, we investigated the effect of curcumin on the ER-associated degradation (ERAD) and estrogenic signaling in prostate cancer cells. The antiproliferative effect of curcumin on human androgen-dependent prostate cancer cell lines LNCaP and VCaP was estimated by WST-1 assay. Morphological alterations were investigated with an inverted microscope. We investigated the effect of curcumin on ERAD and estrogen signaling proteins by immunoblotting assay. To evaluate the impact of curcumin on endoplasmic reticulum (ER) protein quality-related, the expression level of 32 genes was analyzed by quantitative reverse transcription polymerase chain reaction. The nuclear translocation of estrogen receptor was examined by nuclear fractionation and immunofluorescence microscopy. We found that curcumin effectively reduced the proliferation rates of LNCaP and VCaP cells. ERAD proteins; Hrd1, gp78, p97/VCP, Ufd1 and Npl4 were strongly induced by curcumin. Also, the steady-state level of polyubiquitin was increased in a dose-dependent manner in both cell lines. Curcumin administration remarkably decreased the protein levels of estrogen receptor-alfa (Erα), whereas estrogen receptor-beta unaffected. Additionally, curcumin strongly restricted the nuclear translocation of Erα. Present data suggest that curcumin may be effectively used in therapeutic approaches associated with the targeting ER protein quality control mechanism and modulation of estrogen signaling in prostate cancer.

Anticancer and anti-metastasis activity of 1,25 dihydroxycholecalciferols and genistein in MCF-7 and MDA-MB-231 breast cancer cell lines

A powerful steroid hormone precursor, 1,25 dihydroxycholecalciferols (1,25(OH)2D3), and dietary phytoestrogen (genistein) are essential compounds that act by binding to nuclear receptors and altering gene expression. They have many biological benefits, some of which have anticancer properties. We studied the impact of 1,25(OH)2D3 and genistein on the proliferation, progression, and metastasis of MCF-7 and MDA-MB-231 cells when they were used alone or in combination and investigated whether there was a synergistic effect between genistein and 1,25(OH)2D3. To achieve these goals, a variety of assays, including flow cytometry, cell invasion assays, cell adhesion assays, Western blotting, and RT‒PCR, were used. Our findings showed that genistein, 1,25(OH)2D3, and the two combined all effectively declined the growth of MCF-7 and MDA-MB-231 cells by arresting the cells in the G0/G1 phase and inducing an apoptotic pathway. Stimulation of apoptosis was achieved by upregulating the expression of BAX and CASP3 genes and downregulating the expression levels of BCL-2 gene. Furthermore, both compounds suppress metastasis by reducing cell adhesion and cell migration/invasion by elevating the expression level of E-cadherin and reducing the expression level of P-cadherin and N-cadherin. Additionally, both genistein and 1,25(OH)2D3 increased the expression level of ERK1 and reduced the expression levels of JNK, p38, Ras, and MEK proteins, which reduced metastasis, enhanced the response to cancer treatment, and improved overall survival. Thus, genistein and 1,25(OH)2D3 can both be considered key candidates in the search for new breast cancer treatments.

Causal effects of genetically predicted endometriosis on breast cancer: a two-sample Mendelian randomization study

This study used a Mendelian randomization (MR) approach to investigate the causal relationship between genetically predicted endometriosis (EMS) and breast cancer risk. A total of 122,977 cases and 105,974 controls were included in the analysis, with gene-level summary data obtained from the Breast Cancer Association Consortium (BCAC). An inverse variance-weighting approach was applied to assess the causal relationship between EMS and breast cancer risk, and weighted median and MR-Egger regression methods were used to evaluate pleiotropy. Results showed a causal relationship between EMS and a decreased risk of overall breast cancer (odds ratio [OR] 0.95; 95% CI 0.90-0.99, p = 0.02). Furthermore, EMS was associated with a lower risk for estrogen receptor (ER)-positive breast cancer in a subgroup analysis based on immunohistochemistry type (OR 0.91; 95% CI 0.86-0.97, p = 0.005). However, there was no causal association between ER-negative breast cancer and survival (OR 1.00; 95% CI 0.94-1.06, p = 0.89). Pleiotropy was not observed. These findings provide evidence of a relationship between EMS and reduced breast cancer risk in invasive breast cancer overall and specific tissue types, and support the results of a previous observational study. Further research is needed to elucidate the mechanisms underlying this association.

Trends in estrogen and progesterone receptors in prostate cancer: a bibliometric analysis

Introduction

The bibliometric analysis aims to identify research trends in estrogen receptor (ERs) and progesterone receptor (PRs) in prostate cancer (PCa), and also discuss the hotspots and directions of this field.

Methods

835 publications were sourced from the Web of Science database (WOS) from 2003 to 2022. Citespace, VOSviewer, and Bibliometrix were used for the bibliometric analysis.

Results

The number of published publications increased in early years, but declined in the last 5 years. The United States was the leading country in citations, publications, and top institutions. Prostate and Karolinska Institutet were the most publications of journal and institution, respectively. Jan-Ake Gustafsson was the most influential author based on the number of citations/publications. The most cited paper was "Estrogen receptors and human disease" by Deroo BJ, published in the Journal of Clinical Investigation. The most frequently used keywords were PCa (n = 499), gene-expression (n = 291), androgen receptor (AR) (n = 263), and ER (n = 341), while ERb (n = 219) and ERa (n = 215) further emphasized the importance of ER.

Conclusions

This study provides useful guidance that ERa antagonists, ERb agonists, and the combination of estrogen with androgen deprivation therapy (ADT) will potentially serve as a new treatment strategy for PCa. Another interesting topic is relationships between PCa and the function and mechanism of action of PRs subtypes. The outcome will assist scholars in gaining a comprehensive understanding of the current status and trends in the field, and provide inspiration for future research.

The Co-Expression of Estrogen Receptors ERα, ERβ, and GPER in Endometrial Cancer

Estrogens have important roles in endometrial cancer (EC) and exert biological effects through the classical estrogen receptors (ERs) ERα and ERβ, and the G-protein-coupled ER, GPER. So far, the co-expression of these three types of ERs has not been studied in EC. We investigated ERα, ERβ, GPER mRNA and protein levels, and their intracellular protein distributions in EC tissue and in adjacent control endometrial tissue. Compared to control endometrial tissue, immunoreactivity for ERα in EC tissue was weaker for nuclei with minor, but unchanged, cytoplasmic staining; mRNA and protein levels showed decreased patterns for ERα in EC tissue. For ERβ, across both tissue types, the immunoreactivity was unchanged for nuclei and cytoplasm, although EC tissues again showed lower mRNA and protein levels compared to adjacent control endometrial tissue. The immunoreactivity of GPER as well as mRNA levels of GPER were unchanged across cancer and control endometrial tissues, while protein levels were lower in EC tissue. Statistically significant correlations of estrogen receptor α (ESR1) versus estrogen receptor β (ESR2) and GPER variant 3,4 versus ESR1 and ESR2 was seen at the mRNA level. At the protein level studied with Western blotting, there was significant correlation of ERα versus GPER, and ERβ versus GPER. While in clinical practice the expression of ERα is routinely tested in EC tissue, ERβ and GPER need to be further studied to examine their potential as prognostic markers, provided that specific and validated antibodies are available.

Prostate Cancer Review: Genetics, Diagnosis, Treatment Options, and Alternative Approaches

Simple Summary

Prostate cancer affects men of all racial and ethnic groups and leads to higher rates of mortality in those belonging to a lower socioeconomic status due to late detection of the disease. There is growing evidence that suggests the contribution of an individual’s genetic profile to prostate cancer. Currently used prostate cancer treatments have serious adverse effects; therefore, new research is focusing on alternative treatment options such as the use of genetic biomarkers for targeted gene therapy, nanotechnology for controlled targeted treatment, and further exploring medicinal plants for new anticancer agents. In this review, we describe the recent advances in prostate cancer research.

Abstract

Prostate cancer is one of the malignancies that affects men and significantly contributes to increased mortality rates in men globally. Patients affected with prostate cancer present with either a localized or advanced disease. In this review, we aim to provide a holistic overview of prostate cancer, including the diagnosis of the disease, mutations leading to the onset and progression of the disease, and treatment options. Prostate cancer diagnoses include a digital rectal examination, prostate-specific antigen analysis, and prostate biopsies. Mutations in certain genes are linked to the onset, progression, and metastasis of the cancer. Treatment for localized prostate cancer encompasses active surveillance, ablative radiotherapy, and radical prostatectomy. Men who relapse or present metastatic prostate cancer receive androgen deprivation therapy (ADT), salvage radiotherapy, and chemotherapy. Currently, available treatment options are more effective when used as combination therapy; however, despite available treatment options, prostate cancer remains to be incurable. There has been ongoing research on finding and identifying other treatment approaches such as the use of traditional medicine, the application of nanotechnologies, and gene therapy to combat prostate cancer, drug resistance, as well as to reduce the adverse effects that come with current treatment options. In this article, we summarize the genes involved in prostate cancer, available treatment options, and current research on alternative treatment options.

Nutraceuticals: Focus on Anti-Inflammatory, Anti-Cancer, Antioxidant Properties in Gastrointestinal Tract

In recent years, nutraceuticals have gained great popularity, owing to their physiological and potential health effects, such as anti-inflammatory, anti-cancer, antioxidant, and prebiotic effects, and their regulation of lipid metabolism. Since the Mediterranean diet is a nutritionally recommended dietary pattern including high-level consumption of nutraceuticals, this review aimed to summarize the main results obtained by our in vitro and in vivo studies on the effects of the major constituents of the Mediterranean diet (i.e., extra virgin olive oil compounds, polyunsaturated fatty acids, and fruit components). Based on experimental studies, the therapeutic purpose of nutraceuticals depends on their bioavailability, solubility, toxicity, and delivery system. This review provides more in-depth knowledge on the effects linked to nutraceuticals administration on human health, focusing the gastrointestinal tract and suggesting specific dietary components for personalized adjuvant therapies.

Estradiol and Estrogen-like Alternative Therapies in Use: The Importance of the Selective and Non-Classical Actions

Estrogen is one of the most important female sex hormones, and is indispensable for reproduction. However, its role is much wider. Among others, due to its neuroprotective effects, estrogen protects the brain against dementia and complications of traumatic injury. Previously, it was used mainly as a therapeutic option for influencing the menstrual cycle and treating menopausal symptoms. Unfortunately, hormone replacement therapy might be associated with detrimental side effects, such as increased risk of stroke and breast cancer, raising concerns about its safety. Thus, tissue-selective and non-classical estrogen analogues have become the focus of interest. Here, we review the current knowledge about estrogen effects in a broader sense, and the possibility of using selective estrogen-receptor modulators (SERMs), selective estrogen-receptor downregulators (SERDs), phytoestrogens, and activators of non-genomic estrogen-like signaling (ANGELS) molecules as treatment.

Sleep disorders and prostate cancer prognosis: biology, epidemiology, and association with cancer development risk

Sleep is crucial for the maintenance of health and well-being. Sleep disorders can result in physiological consequences and are associated with several health issues, including cancer. Cancer is one of the most significant health problems in the world. In Western countries, prostate cancer is the most prevalent noncutaneous cancer among men. Epidemiological studies showed that one in nine men will have this disease during their life. Many factors influence prostate cancer and the tumor niche, including endogenous hormones, family history, diet, and gene mutations. Disruption of the circadian cycle by sleep disorders or other factors has been suggested as a novel and important risk factor for prostate cancer and its tumorigenesis. This review presents information regarding the epidemiological and biological aspects of prostate cancer, and discusses the impact of sleep physiology and sleep disorders on this type of cancer, highlighting possible associations with risk of cancer development.

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.

Decreased Expression of Estrogen Receptors Is Associated with Tumorigenesis in Papillary Thyroid Carcinoma

Papillary thyroid carcinomas (PTC), which is derived from thyroid follicular cells, is the most commonly differentiated thyroid cancer with sex disparity. However, the role of estrogen receptors (ERs) in the pathogenesis of PTC remains unclear. The present study aimed to determine the association of ER mRNA expression levels with clinicopathologic features in PTC. To that aim, the mRNA levels of ESR1 (ERα66), ESR1 (ERα36), ESR2, and G-protein-coupled estrogen receptor 1 (GPER1) in snap-frozen tissue samples from PTCs and adjacent normal thyroid tissues were determined using quantitative reverse transcription polymerase chain reaction (RT-qPCR), and the correlation between ER mRNA expression levels and clinicopathologic features was analyzed. The expression of ERα66, ERα36, ERβ, and GPER1 was lower in PTC specimens than in adjacent normal thyroid tissues. Moreover, low GPER1 expression was associated with extrathyroidal extension. There was no obvious difference in expression of ERs between PTC specimens from male and female patients. In conclusion, our findings highlight the importance of ERs in PTC tumorigenesis.

Molecular Proof of a Clinical Concept: Expression of Estrogen Alpha-, Beta-Receptors and G Protein-Coupled Estrogen Receptor 1 (GPER) in Histologically Assessed Common Nevi, Dysplastic Nevi and Melanomas

Background and Objectives: Epidemiologic data show significant differences in melanoma incidence and outcomes between sexes. The role of hormonal receptors in the pathogenesis of melanocytic lesions remains unclear, thus we performed this study aiming to assess estrogen receptors expression in different melanocytic lesions. Materials and Methods: We performed a cross-sectional study that included 73 consecutively excised melanocytic lesions. Estrogen receptor alpha (ERα), beta (ERβ), and G-protein coupled estrogen receptor (GPER) expression was analyzed in melanocytes and keratinocytes of common nevi, dysplastic nevi, melanoma, healthy skin margin, and in sebaceous and sweat gland cells. Results: ERβ expression was higher in dysplastic nevi margin melanocytes compared to common nevi (p = 0.046) and in dysplastic nevi keratinocytes compared to melanoma keratinocytes (p = 0.021). ERβ expression was significantly higher in margin melanocytes compared to melanoma melanocytes (p = 0.009). No difference in ERβ expression was shown between melanocytes of three types of lesions. GPER expression was higher in nuclei and cytoplasm of dysplastic nevi (p = 0.02 and p = 0.036 respectively) and at the margin compared to melanoma. GPER expression was lower in sebaceous glands of tissue surrounding common nevi (p = 0.025) compared to dysplastic nevi. GPER expression was higher in skin margin tissue melanocytes (p = 0.016 nuclear, p = 0.029 cytoplasmic) compared to melanoma melanocytes. There were no differences in ERα expression between the melanocytic lesions. Conclusion: Further large-scale studies are warranted to investigate the potential role of ERβ and GPER in the pathogenesis of melanocytic lesions.

Improvement of Biophysical Skin Parameters of Topically Applied Fermented Soybean Extract-Loaded Niosomes with No Systemic Toxicity in Ovariectomized Rats

Despite the known beneficial impacts of estrogen used as hormone replacement therapy to ameliorate signs of skin aging in postmenopausal women, its compliance rates are low. A significant amount of estrogen may be absorbed into the blood circulation and can lead to systemic actions. Soy isoflavone exhibits biological activities similar to synthetic estrogen because it is a heterocyclic phenolic compound. The disadvantage of most topical ingredients based on isoflavone is that they contain biologically inactive glycoside forms, which must be converted to a readily absorbed aglycone for the topical application. The purposes of this study were to develop niosomes-loaded Aspergillus oryzae-fermented soybean extract (FSE) to enhance skin absorption with proven systemic side effect compared to estrogen application. Skin hydration and viscoelasticity of 75 days post-ovariectomized (OVX) Wistar rats following 84-day topical treatment with various tested gel formulations containing fermented soybean extract (FSE) were evaluated. The tested formulations were gel + FSE nanoniosomes, gel + FSE microniosomes, gel + FSE (200 µg FSE/9 cm²/rat), gel + blank nanoniosomes (a negative control), and gel + 17β-estradiol (E2) nanoniosomes (a positive control, 20 µg E2/9 cm²/rat). Changes in vaginal cornifications and weights of uteri, livers, and kidneys in the OVX rats and signs of primary skin irritation in the rabbits were evaluated for their toxicities. Results showed that FSE-loaded nanoniosomes improved the skin hydration and viscoelasticity better than gel + FSE microniosomes and gel + FSE, respectively, but lower than those of gel + E2 nanoniosomes (p < 0.05). Unlike all gel + E2 nanoniosomes, the FSE formulations showed no changes in vaginal cells and weights of uteri, livers, and kidneys and no signs of skin irritation. In conclusion, The FSE niosome-based gels should be promising candidates for delivering phytoestrogens against signs of skin aging with no systemic toxicities.

Association between the polygenic liabilities for prostate cancer and breast cancer with biochemical recurrence after radical prostatectomy for localized prostate cancer

Prostate and breast cancers are hormone-related malignancies and are characterized by a complex interplay of hundreds of susceptibility loci throughout the genome. Prostate cancer could be inhibited by eliminating androgens through castration or estrogen administration, thus facilitating long-term treatment of prostate cancer; however, the role of estrogen in prostate cancer remains unclear. This study aimed to determine whether polygenic risk scores (PRSs) comprising combinations of genome-wide susceptibility variants influence the clinical outcomes of prostate cancer patients. The study subjects were recruited from four medical centers in Taiwan, and genome-wide genotyping data were obtained from 643 prostate cancer patients. We derived the PRS for prostate cancer (PRS-PC) and for breast cancer (PRS-BC) for each patient. The association between the PRS-PC/PRS-BC at the age of prostate cancer onset and recurrence within seven years was evaluated using a regression model adjusted for population stratification components. A higher PRS-PC was associated with an earlier onset age for prostate cancer (beta in per SD increase in PRS = -0.89, P = 0.0008). In contrast, a higher PRS-BC was associated with an older onset age for prostate cancer (beta = 0.59, P = 0.02). PRS-PC was not associated with the risk of recurrence (hazard ratio = 1.03, P = 0.67), whereas a higher PRS-BC was associated with a low recurrence risk (hazard ratio = 0.86, P = 0.03). These results indicate that the genetic predisposition to breast cancer is associated with a low risk of prostate cancer recurrence. Further studies are warranted to explore the role of breast cancer susceptibility variants and estrogen signaling in prostate cancer progression.

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.

Raloxifene inhibits pancreatic adenocarcinoma growth by interfering with ERβ and IL-6/gp130/STAT3 signaling

PURPOSE

Currently, the exact role of estrogen receptor (ER) signaling in pancreatic cancer is unknown. Recently, we showed that expression of phosphorylated ERβ correlates with a poor prognosis in patients with pancreatic ductal adenocarcinoma (PDAC). Here, we hypothesized that raloxifene, a FDA-approved selective ER modulator (SERM), may suppress PDAC tumor growth by interfering with ERβ signaling. To test this hypothesis, we studied the impact of raloxifene on interleukin-6/glycoprotein-130/signal transducer and activator of transcription-3 (IL-6/gp130/STAT3) signaling.

METHODS

Human PDAC cell lines were exposed to raloxifene after which growth inhibition was assessed using a BrdU assay. ER knockdown was performed using siRNAs specific for ERα and ERβ. The effects of raloxifene on IL-6 expression and STAT3 phosphorylation in PDAC cells were assessed by ELISA and Western blotting, respectively. In addition, raloxifene was administered to an orthotopic PDAC tumor xenograft mouse model, after which tumor growth was monitored and immunohistochemistry was performed.

RESULTS

Raloxifene inhibited the in vitro growth of PDAC cells, and this effect was reversed by siRNA-mediated knockdown of ERβ, but not of ERα, indicating ER isotype-specific signaling. We also found that treatment with raloxifene inhibited the release of IL-6 and suppressed the phosphorylation of STAT3Y705 in PDAC cells. In vivo, we found that orthotopic PDAC tumor growth, lymph node and liver metastases as well as Ki-67 expression were reduced in mice treated with raloxifene.

CONCLUSIONS

Inhibition of ERβ and the IL-6/gp130/STAT3 signaling pathway by raloxifene leads to potent reduction of PDAC growth in vitro and in vivo. Our results suggest that ERβ signaling and IL-6/gp130 interaction may serve as promising drug targets for pancreatic cancer and that raloxifene may serve as an attractive therapeutic option for PDAC patients expressing the ERβ isotype.

Endocrinology of the Aging Prostate: Current Concepts

Benign prostate hyperplasia (BPH), one of the most common diseases in older men, adversely affects quality-of-life due to the presence of low urinary tract symptoms (LUTS). Numerous data support the presence of an association between BPH-related LUTS (BPH-LUTS) and metabolic syndrome (MetS). Whether hormonal changes occurring in MetS play a role in the pathogenesis of BPH-LUTS is a debated issue. Therefore, this article aimed to systematically review the impact of hormonal changes that occur during aging on the prostate, including the role of sex hormones, insulin-like growth factor 1, thyroid hormones, and insulin. The possible explanatory mechanisms of the association between BPH-LUTS and MetS are also discussed. In particular, the presence of a male polycystic ovarian syndrome (PCOS)-equivalent may represent a possible hypothesis to support this link. Male PCOS-equivalent has been defined as an endocrine syndrome with a metabolic background, which predisposes to the development of type II diabetes mellitus, cardiovascular diseases, prostate cancer, BPH and prostatitis in old age. Its early identification would help prevent the onset of these long-term complications.

A methylation signature at the CpG island promoter of estrogen receptor beta (ER-β) in breasts of women may be an early footmark of lack of breastfeeding and nulliparity

Although little is known regarding the mechanisms behind the onset of breast cancer (BC) through reproductive risk factors, new researches have highlighted some early tumor-related methylation footmarks in the breast tissue of apparently clinically healthy women as their potential epigenetic mechanism. Previous evidence supports that the estrogen receptor beta (ER-β), whose anti-cancer roles had already been revealed in BC, is downregulated in the breasts of healthy nulliparous women. Nevertheless, data on such a link about its methylation alterations have not been reported. The goal of current study was to determine possible methylation alterations at CpG island promoter of the ER-β gene, including promoter 0 N and exon 0 N, in relation to aspects of reproductive history in the healthy breasts. The DNA was extracted from the breasts of 120 subjects undergoing cosmetic mammoplasty. Thereafter, the methylation levels of targeted regions in ER-β gene were determined by using MeDIP-qPCR assay. The results revealed that ER-β exon 0 N had no methylation in 84.2 % of the women, whereas the rest, comprising 2.5 % and 13.3 % of the samples, showed a lower and higher of its methylation, respectively. Interestingly, nulliparous women were found to have an elevated methylation level of the ER-β exon 0 N than parous women (P = 0.036). Moreover, we observed a high methylation of the ER-β exon 0 N in the breasts of non-breastfeeding women compared to breastfeeding subgroup (P = 0.048). Likewise, the non-breastfeeding subgroup showed exon 0N high methylation in comparison to women with breastfeeding >24 months (P = 0.023). Finally, although we found that 6.67 % of the samples had a high methylation level at the promoter 0N, no any relationship was found between its methylation and reproductive history. These results may provide key clues to revealing the epigenetic mechanism through which the nulliparity and lack of breastfeeding influencing the risk factor of BC as well as introducing the potential new early prediction and prevention strategies. Although further investigations need to be done in order to gain a better understanding the roles of these epigenetic signatures.

Scientific Evidence Supporting the Beneficial Effects of Isoflavones on Human Health

Isoflavones are phenolic compounds with a chemical structure similar to that of estradiol. They are present in several vegetables, mainly in legumes such as soy, white and red clover, alfalfa and beans. The most significant food source of isoflavones in humans is soy-derived products. Isoflavones could be used as an alternative therapy for pathologies dependent on hormonal disorders such as breast and prostate cancer, cardiovascular diseases, as well as to minimize menopausal symptoms. According to the results gathered in the present review, it can be stated that there is scientific evidence showing the beneficial effect of isoflavones on bone health and thus in the prevention and treatment of osteoporosis on postmenopausal women, although the results do not seem entirely conclusive as there are discrepancies among the studies, probably related to their experimental designs. For this reason, the results should be interpreted with caution, and more randomized clinical trials are required. By contrast, it seems that soy isoflavones do not lead to a meaningful protective effect on cardiovascular risk. Regarding cancer, scientific evidence suggests that isoflavones could be useful in reducing the risk of suffering some types of cancer, such as breast and endometrial cancer, but further studies are needed to confirm these results. Finally, isoflavones could be useful in reducing hot flushes associated with menopause. However, a limitation in this field is that there is still a great heterogeneity among studies. Lastly, with regard to isoflavone consumption safety, it seems that they are safe and that the most common adverse effect is mild and occurs at the gastrointestinal level.

Indole Derivative Interacts with Estrogen Receptor Beta and Inhibits Human Ovarian Cancer Cell Growth

Ovarian cancer remains the leading cause of mortality among gynecological tumors. Estrogen receptor beta (ERβ) expression has been suggested to act as a tumor suppressor in epithelial ovarian cancer by reducing both tumor growth and metastasis. ERβ expression abnormalities represent a critical step in the development and progression of ovarian cancer: for these reasons, its re-expression by genetic engineering, as well as the use of targeted ERβ therapies, still constitute an important therapeutic approach. 3-{[2-chloro-1-(4-chlorobenzyl)-5-methoxy-6-methyl-1H-indol-3-yl]methylene}-5-hydroxy-6-methyl-1,3-dihydro-2H-indol-2-one, referred to here as compound 3, has been shown to have cytostatic as well cytotoxic effects on various hormone-dependent cancer cell lines. However, the mechanism of its anti-carcinogenic activity is not well understood. Here, we offer a possible explanation of such an effect in the human ovarian cancer cell line IGROV1. Chromatin binding protein assay and liquid chromatography mass spectrometry were exploited to localize and quantify compound 3 in cells. Molecular docking was used to prove compound 3 binding to ERβ. Mass spectrometry-based approaches were used to analyze histone post-translational modifications. Finally, gene expression analyses revealed a set of genes regulated by the ERβ/3 complex, namely CCND1, MYC, CDKN2A, and ESR2, providing possible molecular mechanisms that underline the observed antiproliferative effects.

Acrylamide impairs ovarian function by promoting apoptosis and affecting reproductive hormone release, steroidogenesis and autophagy-related genes: An in vivo study

Acrylamide (ACR) toxicity is quite common due to its widespread use in industry and due to the Maillard browning reaction that occurs in foods containing high concentrations of hydrocarbons subjected to high temperatures. This study aimed to elucidate the female reproductive toxicity of ACR in vivo. Fifty-day-old Wistar-Albino female rats were treated with different dosages of ACR (2.5, 10, and 50 mg/kg/day). After treatment, the animals were sacrificed, and serum and ovary samples were collected for histological examination, hormone analysis, TUNEL analysis, and RT-PCR studies. We found that ACR acts by significantly reducing ovarian weight and serum progesterone and estradiol concentrations. In addition, ACR treatment led to pyknotic, heterochromatic characteristics and nuclear fragmentation, as evidenced by hematoxylin staining. The TUNEL assay revealed that granulosa cells were affected after the oral administration of ACR, leading to the apoptosis of follicles at different stages of growth. Compared with the control condition, high doses of ACR (50 mg/kg/day) significantly induced the overexpression of INSL3, CYP17a, IGF1, ESR1, ESR2, ATG5, ATG12 and LC3 in the ovary. Moreover, LC3 mRNA levels significantly increased with increasing doses of ACR (2.5, 10 and 50 mg/kg/day), suggesting that ACR treatment induced autophagy. In conclusion, ACR induced ovarian dysfunction by affecting steroid hormone release, increasing apoptosis and mRNA levels of autophagy-related genes. The eventual correlation between apoptotic granulosa cell death and autophagy needs to be further explored.

Insights into the Role of Estrogen Receptor β in Triple-Negative Breast Cancer

Estrogen receptors (ERα and ERβ) are ligand-activated transcription factors that play different roles in gene regulation and show both overlapping and specific tissue distribution patterns. ERβ, contrary to the oncogenic ERα, has been shown to act as an oncosuppressor in several instances. However, while the tumor-promoting actions of ERα are well-known, the exact role of ERβ in carcinogenesis and tumor progression is not yet fully understood. Indeed, to date, highly variable and even opposite effects have been ascribed to ERβ in cancer, including for example both proliferative and growth-inhibitory actions. Recently ERβ has been proposed as a potential target for cancer therapy, since it is expressed in a variety of breast cancers (BCs), including triple-negative ones (TNBCs). Because of the dependence of TNBCs on active cellular signaling, numerous studies have attempted to unravel the mechanism(s) behind ERβ-regulated gene expression programs but the scenario has not been fully revealed. We comprehensively reviewed the current state of knowledge concerning ERβ role in TNBC biology, focusing on the different signaling pathways and cellular processes regulated by this transcription factor, as they could be useful in identifying new diagnostic and therapeutic approaches for TNBC.

Association of finasteride with prostate cancer: A systematic review and meta-analysis

BACKGROUND

The Prostate Cancer Prevention Trial has shown a protective effect of finasteride on prostate cancer, but it also showed that finasteride can increase the risk of high-grade prostate cancer. Several studies have investigated the relationship between finasteride and prostate cancer, but these studies have shown inconsistent results.

ETHICS

The protocol was approved by the institutional review board of each study center. Written informed consent will be obtained from all patients before registration, in accordance with the Declaration of Helsinki.

METHODS

We performed a systematic literature review and meta-analysis to assess the association between finasteride and prostate cancer. Systematic literature searches were conducted using PubMed, EMBASE, Science Direct/Elsevier, MEDLINE, CNKI, and the Cochrane Library up to October 2018 to identify studies that involved the relationship between finasteride and prostate cancer. Meta-analysis was performed using Review Manager and Stata software. Combined ORs were identified with 95% confidence intervals (95% CI) in a random or fixed effects model.

RESULTS

Eight studies were identified, including 54,335 cases of patients that used finasteride and 9197 patients who served as placebo controls. Our results illustrate that there is a significant correlation between finasteride use and prostate cancer with combined ORs of 0.70 [0.51, 0.96]. A significant correlation between finasteride use and high-grade prostate cancer was also observed with combined ORs of 2.10 [1.85, 2.38].

CONCLUSIONS

This study confirms that finasteride significantly reduced the risk of prostate cancer; however, the malignant degree of prostate cancer was increased. Studies with larger sample sizes are needed to better clarify the correlation between finasteride use and prostate cancer.

Environmental toxin exposure in polycystic ovary syndrome women and possible ovarian neoplastic repercussion

Purpose: Over the last two decades, increasing attention has been paid to environmental toxins and their effects on the female reproductive system. Endocrine disrupting chemicals (EDCs) are exogenous substances or mixtures that can mimic the action of steroid hormones and interfere with their metabolism. Advanced glycation end products (AGEs) are proinflammatory molecules that can interact with cell surface receptors and mediate the triggering of proinflammatory pathways and oxidative stress. The purpose of this review is to explore the effects of environmental toxin exposure in the pathogenesis of both polycystic ovary syndrome (PCOS) and OC (ovarian cancer), considered separately, and also to evaluate possible neoplastic ovarian repercussion after exposure in patients diagnosed with PCOS.Materials and methods: We searched PubMed for articles published in the English language with the use of the following MeSH search terms: "polycystic ovary syndrome" and "ovarian cancer" combined with "endocrine disruptors". Titles and abstracts were examined and full articles that met the selection criteria were retrieved. A manual search of review articles and cross-references completed the search.Results: Extensive data from different studies collected in recent years concerning the effects of EDC/AGE exposure have confirmed their role in the pathophysiology of both PCOS and OC. They favor PCOS/OC development through different mechanisms that finally lead to hormonal and metabolic disruption and epigenetic modifications.Conclusions: Environmental toxin exposure in PCOS women could favor neoplastic transformation by exacerbating and potentiating some PCOS features. Further research, although difficult, is needed in order to prevent further diffusion of these substances in the environment, or at least to provide adequate information to the population considered at risk.

Risk of endometrial cancer among women with benign ovarian tumors - A Danish nationwide cohort study

OBJECTIVE

The few studies on the association between benign ovarian tumors and endometrial cancer have been inconclusive. Using data from a large Danish register-based cohort study, we assessed the overall and type-specific risk of endometrial cancer among women with a benign ovarian tumor.

METHODS

We identified all Danish women diagnosed with a benign ovarian tumor during 1978-2016 in the Danish National Patient Register (n = 149,807). The study population was followed for subsequent development of endometrial cancer by linkage to the Danish Cancer Register and standardized incidence ratios (SIRs) with corresponding 95% confidence intervals (CIs) were calculated after correction for hysterectomy.

RESULTS

After a one-year delayed study entry, women with benign ovarian tumors had a decreased incidence of endometrial cancer (SIR = 0.74, 95% CI: 0.68-0.81) compared with women in the general Danish population. Both solid benign ovarian tumors (SIR = 0.79, 95% CI 0.70-0.88) and cystic benign ovarian tumors (SIR = 0.68, 95% CI 0.58-0.78) were associated with decreased incidences of endometrial cancer. Likewise, women with benign ovarian tumors had decreased incidences of both type I and type II endometrial cancer. The incidence of endometrial cancer was decreased to virtually the same magnitude irrespective of the age at diagnosis of a benign ovarian tumor and the reduction persisted throughout the follow-up period.

CONCLUSIONS

The risk of endometrial cancer was decreased beyond the first year after a benign ovarian tumor and the decrease persisted for 20 or more years. The possible underlying mechanisms are not known and should be investigated further.

Outcomes of ovarian stimulation and fertility preservation in breast cancer patients with different hormonal receptor profiles

PURPOSE

To evaluate fertility preservation outcomes in breast cancer women with different hormonal receptor profiles before oncological treatment.

METHODS

The study population included women with a diagnosis of breast cancer who underwent fertility preservation from 2009 until 2018 at a university-affiliated tertiary hospital. Stimulation parameters and fertility preservation outcomes were compared among the following receptor-specific profile groups: (1) estrogen receptor positive (ER+) versus estrogen receptor negative (ER-), (2) triple-negative breast cancer (TNBC) versus estrogen and progesterone receptor positive (ER+/PR+), and (3) TNBC versus non-TNBC. Primary outcome was the total number of mature oocytes. Secondary outcomes included the number of retrieved oocytes, the peak estradiol level, and the number of follicles > 14 mm on the final oocyte maturation trigger day.

RESULTS

A total of 155 cycles were included in the final analysis. These were divided into the exposure groups of ER+ (n = 97), ER- (n = 58), ER+/PR+ (n = 85), TNBC (n = 57), and non-TNBC (n = 98). Cycle outcomes revealed similar number of retrieved oocytes and follicles > 14 mm on the trigger day. Women with TNBC had significantly lower number of mature oocytes compared with those with ER + PR+ (7 (5-11) versus 9 (7-15); p = 0.02) and non-TNBC (7 (5-11) versus 9 (7-16); p = 0.01) status. Triple-negative breast cancer profile was associated with a significant reduction in the chance of developing over 10 mature oocytes (OR 0.41; 95% CI 0.19-0.92).

CONCLUSION

Among the different hormonal receptor profiles in breast cancer, the TNBC subtype has a negative effect on fertility preservation outcomes.

Ventral prostate and mammary gland phenotype in mice with complete deletion of the ERβ gene

Disagreements about the phenotype of estrogen receptor β (ERβ) knockout mouse, created by removing the DNA-binding domain of the ERβ gene or interruption of the gene with a neocassette (Oliver Smithies ERβ knockout mice [ERβ^OS-/-]), prompted us to create an ERβ knockout mouse by deleting the ERβ gene with the use of CRISPR/Cas9 technology. We confirmed that the ERβ gene was eliminated from the mouse genome and that no ERβ mRNA or protein was detectable in tissues of this mouse. Overall the phenotype of the ventral prostate (VP) and mammary gland (MG) in ERβ^crispr-/- mice was similar to, but more severe than, that in the ERβ^OS-/-mice. In the VP of 6-mo-old ERβ^crispr-/- mice there was epithelial hyperplasia, fibroplasia, inflammation, stromal overgrowth, and intraductal cancer-like lesions. This was accompanied by an increase in Ki67 and P63 and loss in DACH1 and PURα, two androgen receptor (AR) repressors. In the MG there was overexpression of estrogen receptor α and progesterone receptor, loss of collagen, increase in proliferation and expression of metalloproteases, and invasive epithelium. Surprisingly, by 18 mo of age, the number of hyperplastic foci was reduced, the ducts of the VP and MG became atrophic, and, in the VP, there was massive immune infiltration and massive desquamation of the luminal epithelial cells. These changes were coincident with reduced levels of androgens in males and estrogens in females. We conclude that ERβ is a tumor suppressor gene in the VP and MG where its loss increases the activity AR and ERα, respectively.

A Review on Sex Steroid Hormone Estrogen Receptors in Mammals and Fish

Steroid hormones play essential roles in the reproductive biology of vertebrates. Estrogen exercises its effect through estrogen receptors and is not only a female reproductive hormone but acts virtually in all vertebrates, including fish, and is involved in the physiological and pathological states in all males and females. Estrogen has been implicated in mandible conservation and circulatory and central nervous systems as well as the reproductive system. This review intended to understand the structure, function, binding affinities, and activations of estrogens and estrogen receptors and to discuss the understanding of the role of sex steroid hormone estrogen receptors in mammals and fish.

Optimized immunohistochemical detection of estrogen receptor beta using two validated monoclonal antibodies confirms its expression in normal and malignant breast tissues

PURPOSE

Significant controversy exists regarding the expression patterns of estrogen receptor beta (ERβ) in normal and diseased breast tissue. To address this issue, we have validated two ERβ antibodies, optimized the IHC protocols for both antibodies and now report the expression patterns of ERβ in normal and malignant breast tissues.

METHODS

ERβ antibody specificity was determined using western blot and IHC analysis. ERβ protein expression patterns were assessed via IHC in normal breast tissue and invasive breast carcinoma. Further, we report the detailed protocol of the ERβ IHC assay developed in our CAP/CLIA certified laboratory to provide a standardized method for future studies.

RESULTS

We have confirmed the specificity of two independent ERβ monoclonal antibodies, one that detects total (i.e., full length plus splice variants 2-5, which do not include the ligand binding domain) ERβ protein (PPZ0506) and one that detects only the full-length form, which includes the ligand binding domain, of ERβ (PPG5/10). Using these two antibodies, we demonstrate that ERβ is highly expressed in normal human breast tissue as well as in 20-30% of invasive breast cancers. Further, these two antibodies exhibited similar staining patterns across multiple different tissues and were highly concordant with regard to determining ERβ positivity in breast cancers.

CONCLUSIONS

ERβ protein was shown to be abundant in the majority of normal breast epithelial cells and is present in 20-30% of breast cancers. Use of these two antibodies, along with their standardized IHC protocols, provide a reference for future studies aimed at determining the utility of ERβ as a prognostic and/or predictive biomarker in various tissues of benign or malignant states.

Promyelocytic Leukemia (PML) gene regulation: implication towards curbing oncogenesis

Dysregulation of PML, a significant tumor suppressor is linked with cancers of different histological origins, with a decreased expression observed with a higher tumor grade. This necessitates studying the mechanisms to maintain a stable expression of PML. However much less is known about the transcriptional regulation of PML, more so in the context of breast carcinoma. ERβ has emerged as a critical factor in understanding breast cancer, especially since a huge proportion of breast cancers are ERα⁻ and thus insensitive to tamoxifen therapy. This study aims to uncover an unidentified mechanism of PML gene regulation and its stabilization in breast cancer via ERβ signalling and the impact on cellular apoptosis. We found that clinical expression of PML positively correlates with that of ERβ both in normal and breast carcinoma samples and inversely correlates with markers of cellular proliferation, hinting towards a possible mechanistic interdependence. Both mRNA and protein expression of PML were increased in response to ERβ overexpression on multiple human breast cancer cell lines. Mechanistically, luciferase reporter assays and chromatin-immunoprecipitation assays demonstrated that ERβ can interact with the PML promoter via ERE and AP1 sites to enhance its transcription. ERβ induced stable PML expression causes a decline of its target protein Survivin and simultaneously provides a stable docking platform leading to stabilisation of its target Foxo3a, further causing transcriptional upregulation of pro-apoptotic factors p21 and p27. Immunohistochemical analyses of cancer and normal breast tissues and functional assays conducted corroborated the findings. Collectively, our study identifies ERβ signalling as a novel mechanism for PML gene regulation in ERα⁻ breast cancer. It also reveals bi-directional downstream effect in which ‘ERβ-PML-(Foxo3a/Survivin)’ network acts as a therapeutic axis by suppressing cellular survival and promoting cellular apoptosis in breast carcinoma.

Epigenetic Dysregulation at the Crossroad of Women's Cancer

An increasingly number of women of all age groups are affected by cancer, despite substantial progress in our understanding of cancer pathobiology, the underlying genomic alterations and signaling cascades, and cellular-environmental interactions. Though our understanding of women’s cancer is far more complete than ever before, there is no comprehensive model to explain the reasons behind the increased incidents of certain reproductive cancer among older as well as younger women. It is generally suspected that environmental and life-style factors affecting hormonal and growth control pathways might help account for the rise of women’s cancers in younger age, as well, via epigenetic mechanisms. Epigenetic regulators play an important role in orchestrating an orderly coordination of cellular signals in gene activity in response to upstream signaling and/or epigenetic modifiers present in a dynamic extracellular milieu. Here we will discuss the broad principles of epigenetic regulation of DNA methylation and demethylation, histone acetylation and deacetylation, and RNA methylation in women’s cancers in the context of gene expression, hormonal action, and the EGFR family of cell surface receptor tyrosine kinases. We anticipate that a better understanding of the epigenetics of women’s cancers may provide new regulatory leads and further fuel the development of new epigenetic biomarkers and therapeutic approaches.

Phytoestrogens: Dietary Intake, Bioavailability, and Protective Mechanisms against Colorectal Neoproliferative Lesions

Phytoestrogens are natural substances that have been extensively studied for their beneficial effect on human health. Herein, we analyzed the data of the literature on the role of phytoestrogens in the prevention of colorectal neoproliferative lesions (CNL). Both in vitro and in vivo studies suggest that the beneficial effects of phytoestrogens on CNL mainly depend on their ability to bind estrogen receptor beta (ERβ) in the intestinal mucosa and counter ER-alpha (ERα) activity. Epidemiological data demonstrate a correlation between the low prevalence of CNL in Eastern populations and the consumption of soy products (phytoestrogen-enriched diet). However, both observational and interventional studies have produced inconclusive results. In our opinion, these discrepancies depend on an inadequate evaluation of phytoestrogen intake (dietary questionnaires were not aimed at establishing phytoestrogen intake) and absorption (depending mainly on the intestinal microbiota of the analyzed subjects). For this reason, in the present review, we performed an overview of phytoestrogen dietary intake and metabolism to offer the reader the opportunity for a better interpretation of the literature. Future prospective trials focusing on the protective effect of phytoestrogens against CNL should take into account both their dietary intake and absorption, considering the effective role of the intestinal microbiota.

Biochemistry and use of soybean isoflavones in functional food development

Soybeans and their food products exist in the market in various forms, ranging from crude oils and bean meals to nutritious products (e.g. soy milk powers). With the availability of technologies for mass production of soy products and for enrichment of soy components (e.g. phospholipids, saponins, isoflavones, oligosaccharides and edible fiber), the nutritional values of soy products have been enhanced remarkably, offering the potential for functional food development. Among different bioactive components in soybeans, one important component is isoflavones, which have been widely exploited for health implications. While there are studies supporting the health benefits of isoflavones, concerns on adverse effects have been raised in the literature. The objective of this article is to review the recent understanding of the biological activities, adverse effects, and use of isoflavones in functional food development.

Evaluation of the epidemiological and prognosis significance of ESR2 rs3020450 polymorphism in ovarian cancer

AIM

To investigate the correlation between the polymorphism of estrogen receptor β gene (ESR2) rs3020450 and cancer susceptibility, and explore the epidemiological significance and the effect of ESR2 expression levels on the prognosis of ovarian cancer.

METHODS

Based on meta-analysis the association between ESR2 rs3020450 polymorphism and cancer susceptibility was estimated and a case-control design was used to verify this result in ovarian cancer. The epidemiological effect of ESR2 rs3020450 polymorphism was assessed by attributable risk percentage (ARP) and population attributable risk percentage (PARP). Kaplan Meier plotters were used to evaluate overall survival (OS) and progression-free survival (PFS) in ovarian cancer patients and GEPIA for the differential expression of ESR2 levels in ovarian cancer and adjacent normal tissues.

RESULTS

The pooled analysis indicated no significant correlation between the ESR2 rs3020450 polymorphism and the cancer susceptibility. In the stratified analysis by cancer types, significantly decreased risk was found in ovarian cancer (AG vs GG: OR = 0.73, 95%CI: 0.53-0.97, P = 0.03). Unconditional logistic regression results of case-control study in ovarian cancer observed significant differences in all comparisons (AG vs GG: OR = 0.81, 95%CI: 0.62-0.98, P = 0.04; AA vs GG: OR = 0.63, 95%CI: 0.42-0.92, P = 0.01 and AG + AA vs GG: OR = 0.73, 95%CI: 0.53-0.96, P < 0.001). Based on meta-analysis and case-control pooled results, ARP and PARP were evaluated respectively in allele (21.95% and7.97%), heterozygote (36.99% and 12.11%) and dominant model (36.84% and 12.97%) of rs3020450 polymorphism in ovarian cancer. The expression levels of ESR2 in normal tissues was significantly higher than that in cancer tissues (OV, Median, 4.7:0.21), and significant correlations were observed between high ESR2 expression levels and long OS (HR = 0.80, 95%CI: 0.70-0.92, P = 0.002) and PFS (HR = 0.767, 95%Cl: 0.67-0.88, P < 0.001).

CONCLUSION

Our results indicated that ESR2 rs3020450 polymorphism was associated with ovarian cancer risk from epidemiological perspective, and high ESR2 expression levels was associated with long survival in patients with ovarian cancer.

The effect of individual and mixtures of mycotoxins and persistent organochloride pesticides on oestrogen receptor transcriptional activation using in vitro reporter gene assays

The mycotoxins zearalenone (ZEN) and alpha-zearalenone (α-ZOL), which are common contaminants of agri-food products, are known for their oestrogenic potential. In addition to mycotoxins, food may also contain pesticides with oestrogenic properties such as 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (p,p'-DDT) and 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE), raising the question on the potential effects of individual and combinations of these xeno-oestrogens on the action of natural oestrogens. The present study employed a mammalian reporter gene assay to assess the effects individual and binary combinations of these environmental and food-borne contaminants on oestrogen nuclear receptor (ER) transactivation. As expected, α-ZOL and ZEN exhibited the strongest oestrogenic potency (EC₅₀: 0.27 ± 0.121 nM and 1.32 ± 0.0956 nM, respectively) whereas p,p'-DDT and p,p'-DDE had weak ER agonistic activity with the maximal response of 28.70 ± 2.97% and 18.65 ± 1.77%, respectively. Concurrent treatment of the mycotoxins and/or pesticides, individually or in binary combination, with 17β-oestradiol (E₂) showed either additive, synergistic or antagonistic interactive effects on E₂-mediated ER response, depending on the combination ratios, the concentration range of xeno-oestrogens, and the concentration of E₂. This study highlights the importance of assessing the mixture effects of chemical contaminants in risk assessment, especially in the area of reproductive and developmental toxicity.

Isoflavones

Phytoestrogens are naturally occurring nonsteroidal phenolic plant compounds that, due to their molecular structure and size, resemble vertebrate steroids estrogens. This review is focused on plant flavonoids isoflavones, which are ranked among the most estrogenic compounds. The main dietary sources of isoflavones for humans are soybean and soybean products, which contain mainly daidzein and genistein. When they are consumed, they exert estrogenic and/or antiestrogenic effects. Isoflavones are considered chemoprotective and can be used as an alternative therapy for a wide range of hormonal disorders, including several cancer types, namely breast cancer and prostate cancer, cardiovascular diseases, osteoporosis, or menopausal symptoms. On the other hand, isoflavones may also be considered endocrine disruptors with possible negative influences on the state of health in a certain part of the population or on the environment. This review deals with isoflavone classification, structure, and occurrence, with their metabolism, biological, and health effects in humans and animals, and with their utilization and potential risks.

Female Sex Hormone Receptor Profiling in Uterine Adenosarcomas

OBJECTIVE

This study aimed to identify the hormonal receptor status in uterine adenosarcoma (AS) and uterine AS with sarcomatous overgrowth (AS + SO), including those with high-grade histologic features (nuclear pleomorphism, atypical mitoses, necrosis), with or without heterologous elements. Estrogen receptor (ER) status, including estrogen receptor α (ERα), estrogen receptor β (ERβ), and G protein-coupled estrogen receptor (GPER), and progesterone receptor (PgR) status were examined.

METHODS

From August 2001 to November 2013, 11 patients with histologic diagnosis of uterine AS were identified. Tumor tissue sections were stained for ERα, ERβ, GPER, and PgR and examined both for percentage of overall cells stained and for intensity of staining. Descriptive statistics were calculated using clinicopathologic data abstracted from the medical record.

RESULTS

Eight cases of AS and 3 cases of AS with high-grade features were identified. Seven of 8 tumor samples of AS showed strong or moderate intensity immunostaining for ERα; all AS + SO tumor samples showed minimal to no immunoreactivity for ERα. There was a significant decrease in ERα H scores in high-grade tumors when compared with AS (P = 0.01). Lower PgR H scores were observed in high-grade tumors compared with those in AS (P = 0.04). Estrogen receptor β immunostaining was variable, and GPER immunostaining was absent in the majority of tumor samples.

CONCLUSIONS

Higher expression of ERα and PgR was observed in AS when compared with those with AS + SO and high-grade features. Both tumor subtypes showed similar levels of ERβ and GPER expression, although significant differences in ERβ and GPER expression were not detected. In contrast to our previous findings in uterine carcinosarcoma, ERs ERβ and GPER do not seem to play a significant role in AS in this study.

Soy supplementation: Impact on gene expression in different tissues of ovariectomized rats and evaluation of the rat model to predict (post)menopausal health effect

•

The usefulness of PBMC gene expressions as a surrogate tissue for risk assessment is questionable.

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SIF in a dose of 2 mg/kg b.w/day is not able to influence ERGs in target tissues such as breast and uterus.

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Plasma concentrations of SIF after 8 weeks oral exposure similar as the recommended dose for humans do not proliferate cells in in vitro cellular models.

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The ovariectomized rat is probably not a good model to predict human risk or benefit assessment of SIF in human.

This toxicogenomic study was conducted to predict (post)menopausal human health effects of commercial soy supplementation using ovariectomized rats as a model. Different target tissues (i.e. breast, uterus and sternum) and non-target tissues (i.e. peripheral blood mononuclear cells (PBMC), adipose and liver) of ovariectomized F344 rats exposed to a commercially available soy supplement for eight weeks, were investigated. Changes in gene expression in these tissues were analysed using whole-genome microarray analysis. No correlation in changes in gene expression were observed among different tissues, indicating tissue specific effects of soy isoflavone supplementation. Out of 87 well-established estrogen responsive genes (ERGs), only 19 were found to be significantly regulated (p < 0.05) in different tissues, particularly in liver, adipose and uterus tissues. Surprisingly, no ERGs were significantly regulated in estrogen sensitive breast and sternum tissues. The changes in gene expression in PBMC and adipose tissue in rats were compared with those in (post)menopausal female volunteers who received the same supplement in a similar oral dose and exposure duration in human intervention studies. No correlation in changes in gene expression between rats and humans was observed. Although receiving a similar dose, in humans the plasma levels expressed as total free aglycones were several folds higher than in the rat. Therefore, the overall results in young ovariectomized female F344 rats indicated that using rat transcriptomic data does not provide a suitable model for human risk or benefit analysis of soy isoflavone supplementation.

Chemoprevention of inflammation-related colorectal cancer by silymarin-, acetyl-11-keto-beta-boswellic acid-, curcumin- and maltodextrin-enriched dietetic formulation in animal model

On the basis of preliminary in vitro experience, we assessed whether an enriched nutritional formulation with estrogen receptor (ER)-beta agonist and anti-inflammatory properties may prevent inflammation-associated colorectal cancer (CRC) in an animal model. Study sample enclosed 110 C57BL/6J male mice. Forty underwent dietary supplement safety assessment (20 standard diet and 20 enriched formulation). Seventy were treated with azoxymethane (AOM)/dextran sulfate sodium and divided into two groups: 35 received standard diet and 35 enriched formulation (curcumin, boswellic acids, silymarin and maltodextrins). Miniature colonoscopy demonstrated colitis and solid lesion development in five mice/group 100 days after first AOM injection. Mice were killed after 10 days. In each group, four subgroups received intraperitoneal bromodeoxyuridine (BrdU) injection at 24th/48th/72nd/96th hour before killing. Anti-inflammatory effect and chemoprevention were evaluated by lesion number/size, histological inflammation/dysplasia/neoplasia assessment, pro-inflammatory cytokine messenger RNA (mRNA), ER-beta/ER-alpha/BrdU immunohistochemistry and TUNEL immunofluorescence. Standard formulation assumption was associated with colon shortening compared with enriched one (P = 0.04), which reduced solid lesion number and size (P < 0.001 for both), histological inflammation score (P = 0.04), pro-inflammatory cytokine mRNA expression (P < 0.001), number of low-grade dysplasia (LGD; P = 0.03) and high-grade dysplasia (P < 0.001) areas. CRC was observed in 69.6% in standard and 23.5% in enriched formulation assuming animals (P < 0.001). Enriched formulation induced lower ER-alpha expression in CRC (P < 0.001) and higher ER-beta expression in LGD (P < 0.001) being associated to higher epithelial turnover (BrdU; P<0.001) in normal mucosa and increased apoptosis in LGD and CRC (P < 0.001 for both). Our results are promising for a successful anti-inflammatory and chemopreventive effect of enriched formulation in CRC arising from inflamed tissue.

Potential Mechanisms of Age Acceleration Caused by Estrogen Deprivation: Do Endocrine Therapies Carry the Same Risks?

Longer duration of endocrine therapy decreases breast cancer recurrence and mortality, but these benefits need to be weighed against potential risks to overall health. Notable side effects of endocrine therapy include cataracts, uterine cancer, thromboembolic events, osteoporosis and fracture risk, chronic musculoskeletal complaints, as well as vaginal dryness and discharge, and vasomotor symptoms. Estrogen deprivation in healthy women younger than 50 years undergoing bilateral oophorectomy has been shown to accelerate the development of diseases related to aging, including coronary artery disease, cardiac arrhythmias, stroke, dementia, and osteoporosis, raising concern that even less dramatic modulation of estrogen homeostasis may adversely affect health outcomes. Diminished available estrogen at the cellular and molecular level may facilitate mechanisms that underlie the aging process, often termed the hallmarks of aging. In this review, we describe estrogen's role in normal physiology across tissues, review the effects of estrogen deprivation on health outcomes in the setting of both surgical and natural menopause, and examine the hallmarks of aging with attention to the effects of estrogen and estrogen blockade on each molecular mechanism underlying the aging process.

Estrogens and prostate cancer

BACKGROUND

Hormonal influences such as androgens and estrogens are known contributors in the development and progression of prostate cancer (CaP). While much of the research to the hormonal nature of CaP has focused on androgens, estrogens also have critical roles in CaP development, physiology as well as a potential therapeutic intervention.

METHODS

In this review, we provide a critical literature review of the current basic science and clinical evidence for the interaction between estrogens and CaP.

RESULTS

Estrogenic influences in CaP include synthetic, endogenous, fungi and plant-derived compounds, and represent a family of sex hormones, which cross hydrophobic cell membranes and bind to membrane-associated receptors and estrogen receptors that localize to the nucleus triggering changes in gene expression in various organ systems.

CONCLUSIONS

Estrogens represent a under-recognized contributor in CaP development and progression. Further research in this topic may provide opportunities for identification of environmental influencers as well as providing novel therapeutic targets in the treatment of CaP.

Polyfluorinated iodine alkanes regulated distinct breast cancer cell progression through binding with estrogen receptor alpha or beta isoforms

Polyfluorinated iodine alkanes (PFIs) are a kind of emerging chemicals with endocrine disrupting effects. Based on the different binding preferences of PFIs to estrogen receptor alpha and beta isoforms (ERα and β), two representative PFIs, dodecafluoro-1,6-diiodohexane (PFHxDI) and tridecafluorohexyl iodide (PFHxI), were selected to evaluate their effects on the proliferation of two kinds of breast cancer cells with different ERα/β expression levels, MCF-7 and T47D. The cell viability assay showed PFHxDI could cause higher cellular toxicity than did PFHxI in both MCF-7 and T47D. MCF-7 with relatively higher ERα/β expression ratio was more vulnerable to the cytotoxic treatments of PFHxI and PFHxDI when compared with T47D cells with relatively lower ERα/β expression ratio. EdU incorporation and cell cycle analysis revealed that, similar to 17β-estrodiol (E₂), non-cytotoxic levels of PFHxDI could significantly promote the proliferation of MCF-7 by increasing cell population at S phase (p < 0.01), while T47D proliferation was not influenced by PFHxI exposure due to cell cycle arrest at G2/M phase. The cellular responses caused by estrogenic PFIs were dominantly mediated by their preferential binding affinities for ER isoforms, which would be helpful in the accurate assessment for their potential influences on the breast cancer progression.

In Vivo Study of the Effects of ERβ on Apoptosis and Proliferation of Hormone-Independent Prostate Cancer Cell Lines PC-3M

OBJECTIVE

To evaluate the in vivo therapeutic effects of attenuated Salmonella carrying PCDNA3.1-ERβ plasmid in hormone-independent prostatic cancer in nude mice and to clarify the mechanism by which estrogen receptor β (ERβ) induces apoptosis and proliferation in prostatic cancer cells in mice.

METHODS

The orthotopic prostatic cancer models of mice were randomly divided as follows: MOCK group, treated with PBS, PQ group, treated with attenuated Salmonella alone, PQ-PCDNA3.1 group, treated with attenuated Salmonella carrying PCDNA3.1 plasmid, and PQ-PCDNA3.1-ERβ group, treated with the attenuated Salmonella carrying PCDNA3.1-ERβ plasmid. Then, 10 μl of the plasmid-containing solution, comprising 1 × 107 cfu of the bacteria, was administered via intranasal delivery to each group except the MOCK group. The experimental methods included flow cytometry and terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) assay, immunohistochemistry, and western blotting.

RESULTS

Compared with the MOCK, PQ, and PQ-PCDNA3.1 groups, the weights of tumors in the PQ-PCDNA3.1-ERβ group were significantly reduced. The results of flow cytometry and TUNEL assay revealed that the number of apoptotic cells in the PQ-PCDNA3.1-ERβ group significantly increased. Compared with PQ-PCDNA3.1 group, the protein expression levels of ERβ, Bad, p-caspase 9, p-caspase 3, and cleaved PARP in the PQ-PCDNA3.1-ERβ group were significantly increased, while the expression levels of Akt, p-Akt, and Bcl-xl were decreased (P < 0.05).

CONCLUSION

The attenuated Salmonella carrying PCDNA3.1-ERβ plasmid could inhibit the growth of orthotopic prostatic cancer in mice by increasing the expression of ERβ.

Bisphenol AF as an Inducer of Estrogen Receptor β (ERβ): Evidence for Anti-estrogenic Effects at Higher Concentrations in Human Breast Cancer Cells

Bisphenols are endocrine disruptors that are widely found in the environment. Accumulating experimental evidence suggests an adverse interaction between bisphenols and estrogen signaling. Most studies have performed experiments that focused on estrogen receptor (ER) engagement by bisphenols. Therefore, the effects of bisphenols on the expression of ERα (ESR1) and ERβ (ESR2) remain largely unknown. In the present study, we examined the effects of four bisphenols: bisphenol A (BPA), bisphenol B (BPB), bisphenol S (BPS), and bisphenol AF (BPAF), on estrogen signaling in two human breast cancer cell lines (MCF-7 and SK-BR-3). Among these bisphenols, BPAF up-regulated the expression of ERβ, and this was coupled with the abrogation of estrogen response element (ERE)-mediated transcriptional activities as well as the down-regulation of Cdc2 expression in MCF-7 cells, without influencing the expression of ERα. BPAF functioned as an agonist of ERα at lower concentrations (nanomolar order), but did not exhibit any modulatory action on ERα transiently expressed in SK-BR-3 cells in the presence or absence of 17β-estradiol (E2) at higher concentrations (micromolar order). The introduction of ERβ cDNA resulted in greater reductions in MCF-7 cell viability than with BPAF alone. Since ERβ is a suppressive molecule of ERα function, these results provide rational evidence for BPAF functioning as an anti-estrogenic compound via the induction of ERβ at higher concentrations.