Expression Of Estrogen Receptor Beta Research Articles

Estrogen receptors alpha and beta expression in different canine cancer types with an emphasis on hematopoietic malignancies.

Estrogen receptors (ERs) are located in both healthy and neoplastic tissues. The type of estrogen receptor expressed varies depending on its location, tumor type, and species. Estrogen action is mediated by binding to ER and activating the transcriptional and signaling processes that result in the control of gene expression. There are two main types of estrogen receptors: ER alpha (ERα) and ER beta (ERβ). Both receptors are functionally different, they may act antagonistically and are distributed in different tissues but their structure is similar - as they are composed of 5 different domains: A/B, C, D, E, and F. The signaling pathway and hence regulation of the gene expression by ERs is a complex and multifactorial process that involves both genomic and nongenomic actions. In the human reproductive tract, both ERα and β are present, with predominant expression of ERβ, while there are no satisfactory data distinguishing the type of ERs expressed in the canine reproductive tract. In mammary gland neoplasia, a decreased or lacking ERα expression in humans is associated with a poorer prognosis. This is similar to dogs, where higher ERα expression intensity was noted in benign tumors than in carcinomas. In human hematopoietic malignancies, ERβ is a predominant receptor. Selective and non-selective ERβ agonists have an antiproliferative and pro-apoptotic effect on human lymphoma cell lines and may be effective in the therapy of ERβ positive lymphomas and leukemias. In canine lymphoma tissues, none or only marginal expression of ERs was detected over the decades. Considering available data, we conducted preliminary studies proving that, in contrast to humans, the dominant ER expressed in canine hematopoietic tumors is ERα.

Estrogen receptor beta expression and role in cancers

Estrogen drives the growth of some cancers, such as breast cancer, via estrogen receptor alpha (ERβ). Estrogen also activates ERβ, but whether ERβ is expressed and has a role in different cancers is debated. The use of nonspecific antibodies has contributed to the confusion, and this review delves into ERβ's controversial role in cancer and focuses on tumor expression that can be supported by non-antibody-dependent assays. We discuss its expression at the transcript level and focus on its potential role in lymphoma, granulosa cell tumor, testicular, and adrenal cancers, emphasizing recent findings and the complexities that necessitate further research.

Shen Yuan extract exerts a hypnotic effect via the tryptophan/5-hydroxytryptamine/melatonin pathway in mice

Ethnopharmacological relevanceSleep plays a critical role in several physiologic processes, and sleep disorders increase the risk of depression, dementia, stroke, cancer, and other diseases. Stress is one of the main causes of sleep disorders. Ginseng Radix et Rhizoma and Polygalae Radix have been reported to have effects of calming the mind and intensifying intelligence in Chinese Pharmacopoeia. Traditional Chinese medicine prescriptions composed of Ginseng Radix et Rhizoma and Polygalae Radix (Shen Yuan, SY) are commonly used to treat insomnia, depression, and other psychiatric disorders in clinical practice. Unfortunately, the underlying mechanisms of the SY extract's effect on sleep are still unknown. Aim of the studyThis study aimed to investigate the hypnotic effect of the SY extract in normal mice and mice with chronic restraint stress (CRS)-induced sleep disorders and elucidate the underlying mechanisms. Materials and methodsThe SY extract (0.5 and 1.0 g/kg) was intragastrically administered to normal mice for 1, 14, and 28 days and to CRS-treated mice for 28 days. The open field test (OFT) and pentobarbital sodium-induced sleep test (PST) were used to evaluate the hypnotic effect of the SY extract. Liquid chromatography-tandem mass spectrometry and enzyme-linked immunosorbent assay were utilized to detect the levels of neurotransmitters and hormones. Molecular changes at the mRNA and protein levels were determined using real-time quantitative polymerase chain reaction and Western blot analysis to identify the mechanisms by which SY improves sleep disorders. ResultsThe SY extract decreased sleep latency and increased sleep duration in normal mice. Similarly, the sleep duration of mice subjected to CRS was increased by administering SY. The SY extract increased the levels of tryptophan (Trp) and 5-hydroxytryptamine (5-HT) and the expression of tryptophan hydroxylase 2 (TPH2) in the cortex of normal mice. The SY extract increased the Trp level, transcription and expression of estrogen receptor beta and TPH2 in the cortex in mice with sleep disorders by decreasing the serum corticosterone level, which promoted the synthesis of 5-HT. Additionally, the SY extract enhanced the expression of arylalkylamine N-acetyltransferase, which increased the melatonin level and upregulated the expressions of melatonin receptor-2 (MT2) and Cryptochrome 1 (Cry1) in the hypothalamus of mice with sleep disorders. ConclusionsThe SY extract exerted a hypnotic effect via the Trp/5-HT/melatonin pathway, which augmented the synthesis of 5-HT and melatonin and further increased the expressions of MT2 and Cry1.

Benzo[a]pyrene exposure affects colorectal cancer susceptibility by regulating ERβ-mediated LINC02977 transcription

Environmental pollutants known as polycyclic aromatic hydrocarbons (PAHs) are produced through the incomplete combustion of organic material. While PAHs have been investigated as genotoxicants, they can also operate through nongenotoxic pathways in estrogen-dependent malignancies, such as breast, cervical and ovarian cancer. However, whether PAHs induce colorectal cancer (CRC) risk through estrogenic effects is still illusive. Here, we systematically investigated the abnormal expression and activation of estrogen receptor beta (ERβ) regulated by PAHs in CRC as well as the underlying mechanisms of ERβ-mediated CRC risk. Based on the 300 plasma samples from CRC patients and healthy controls detected by GC–MS/MS, we found that the plasma concentrations of benzo[a]pyrene (BaP) were significantly higher in CRC cases than in healthy controls, with significant estrogenic effects. Moreover, histone deacetylase 2 (HDAC2)-induced deacetylation of the promoter decreases ERβ expression, which is associated with poor overall survival and advanced tumor stage. The study also revealed that BaP and estradiol (E2) had different carcinogenic effects, with BaP promoting cell proliferation and inhibiting apoptosis, while E2 had the opposite effects. Additionally, this study mapped ERβ genomic binding regions by performing ChIP-seq and ATAC-seq and identified genetic variants of rs1411680 and its high linkage disequilibrium SNP rs6477937, which were significantly associated with CRC risk through meta-analysis of two independent Chinese population genome-wide association studies comprising 2,248 cases and 3,173 controls and then validation in a large-scale European population. By integrating data from functional genomics, we validated the regulatory effect of rs6477937 as an ERβ binding-disrupting SNP that mediated allele-specific expression of LINC02977 in a long-range chromosomal interaction manner, which was found to be highly expressed in CRC tissues. Overall, this study suggests that the different active effects on ERβ by PAHs and endogenous E2 may play a crucial role in the development and progression of CRC and highlights the potential of targeting ERβ and its downstream targets for CRC prevention and treatment.

Effects of matcha tea extract on cell viability and estrogen receptor-β expression on MCF-7 breast cancer cells

PurposeIn the following work, we investigated the effect of matcha green tea extract (MTE) on MCF-7 breast cancer cell viability and estrogen receptor-beta expression (ERβ).MethodsMCF-7 cells were stimulated with MTE at concentrations of 5 and 10 µg/ml. Cell viability was assessed using a water-soluble tetrazolium assay (WST-1 assay) after an incubation time of 72 h. ERβ was quantified at gene level by real-time polymerase chain reaction (PCR). A western blot (WB) was carried out for the qualitative assessment of the expression behavior of on a protein level.ResultsThe WST-1 test showed a significant inhibition of viability in MFC-7 cells after 72 h at 10 µg/ml. The WB demonstrated a significant quantitative decrease of ERβ at protein level with MTE concentrations of 10 µg/ml. In contrast, the PCR did not result in significant downregulation of ERβ.ConclusionMTE decreases the cell viability of MCF-7 cells and furthermore leads to a decrease of ERβ at protein level.

Effects of bisphenol A on murine salivary glands and human tumor cell lines

Bisphenol A (BPA) is an endocrine-disrupting chemical with a potential role in endocrine cancers. However, the effects of BPA on the salivary glands have been barely explored. We investigated the impact of in vivo sub-chronic exposure to BPA and its in vitro effects on human salivary gland mucoepidermoid carcinoma cell lines. Male and female mice were exposed to BPA (30 mg/kg/day). Sublingual and submandibular salivary glands from an estrogen-deficiency model were also analyzed. BPA concentration in salivary glands was evaluated by gas chromatography coupled to ion trap mass spectrometry. Immunohistochemical analysis using anti-p63 and anti-α-SMA antibodies was performed on mouse salivary gland tissues. Gene expression of estrogen receptors alpha and beta, P63 and α-SMA was quantified in mouse salivary gland and/or mucoepidermoid (UM-HMC-1 and UM-HMC-3A) cell lines. Cell viability, p63 and Ki-67 immunostaining were evaluated in vitro. BPA disrupted the tissue architecture of the submandibular and sublingual glands, particularly in female mice, and increased the expression of estrogen receptors and p63, effects that were accompanied by significant BPA accumulation in these tissues. Conversely, ovariectomy slightly impacted BPA-induced morphological changes. In vitro, BPA did not affect the proliferation of neoplastic cells, but augmented the expression of p63 and estrogen receptors. The present data highlight a potential harmful effect of BPA on salivary gland tissues, particularly in female mice, and salivary gland tumor cells. Our findings suggest that estrogen-dependent pathways may orchestrate the effects of BPA in salivary glands.

Correlation between androgen and estrogen receptor expression and clinicopathologic features in carcinoma urinary bladder.

The molecular mapping of cancers by the Cancer Genome Atlas Project has accelerated the quest for new therapeutic targets for urinary bladder cancer, including sex steroid receptors. Previous studies have demonstrated conflicting results on their relationship with bladder cancer, and there is sparse data on their expression in the Indian population. The aim of our study is to examine the expression of androgen receptors (AR) and estrogen receptors (ERα and ERβ) in patients with bladder cancer and their correlation with clinicopathologic features. In this retrospective cohort study, a total of 132 patients, who were surgically managed for urinary bladder mass by transurethral resection or radical cystectomy in our institute, with transitional cell carcinoma on histopathology and with at least two years of follow-up were included. Their demographic and treatment details were obtained, histopathology blocks were retrieved and immunohistochemical staining for androgen and estrogen receptors was performed. Then, the relationship between their expression and clinicopathologic features was studied. A total of 3.79% of patients showed estrogen receptor alpha positivity, 51.52% estrogen receptor beta positivity and 63.64% androgen receptor positivity. No statistically significant correlation was found between age of patients (p = 0.75/0.52/0.87), tumour stage and grade (0.71/0.3/0.21), pathological variant (p = 1/0.58/0.38) and overall survival (p = 0.70/0.052/0.45 for NMIBC and p = 0.82/0.36/0.22) and estrogen receptor alpha, estrogen receptor beta and androgen receptor-positive status, respectively. Estrogen receptor beta positivity was significantly higher in patients with unifocal (p = 0.015) and small tumours (< 5cm) (p = 0.03), and its expression was associated with better disease-free survival (DFS) (p = 0.046) in patients of non-muscle invasive bladder cancer (NMIBC). Our study has the largest sample size conducted on Indian population with results differing from previous studies conducted on western population. Estrogen receptor beta expression was significantly associated with small unifocal tumours and better DFS. Estrogen receptor alpha and androgen receptor expression were not found to be associated with the clinicopathologic features of the study population.

Effects of Pueraria lobata root and Glycine max (L.) Merrill extracts fermented with Lactiplantibacillus plantarum on the depressive-like behavior in ovariectomized mice via upregulation of hippocampal BDNF

Pueraria lobata roots and Glycine max (L.) Merrill are rich in isoflavones, which are phytoestrogens known to alleviate menopausal and some disease symptoms. However, the high molecular weight and poor bioavailability of isoflavones, owing to the glucose moieties attached to these glycosides, limit their practical use. Fermentation with lactic acid bacteria has been reported to convert glycosides into their aglycone forms. In this study, we investigated the health-promoting effects of fermented P. lobata root extract (FPE) and G. max (L.) Merrill extract (FGE) using ovariectomized mice. The extract was fermented with lactic acid bacteria. Lactiplantibacillus plantarum strains that convert glycosides to aglycones were selected, and in vitro and in vivo experiments were conducted to confirm various functionalities resulting from fermentation. FPE and FGE exhibited estrogen-like activities. In particular, fermentation increased the expression of estrogen receptor beta (ERβ), as a result of which the fermented extracts should probably not be associated with increasing the incidence of various female cancers—a common side effect of hormone replacement therapy. In addition, oral administration of FPE, FGE, or a mixture of the two extracts (FPE-FGE) to ovariectomized mice improved depressive symptoms by upregulating hippocampal brain-derived neurotrophic factor (BDNF). The expression of ERβ was the highest in the FPE-FGE group. These results indicate that FPE-FGE can be used as a raw material for the development of dietary supplements for menopausal women because it increases ERβ expression and alleviates the depressive-like behavior through the regulation of BDNF and neurotransmitters.

Association of the Estrogen Receptors Beta Expression with the Ki-67 Proliferative Index in Breast Cancer

Background. Estrogen receptors beta (ERβ) are an important biological regulator and target of antiestrogens, however, unlike estrogen receptors alpha (ERɑ), their significance in the prognosis and treatment of breast cancer remains unclear. Purpose. Evaluation of the ERβ prognostic value in the comparative assessment of frequency and level of the marker expression in groups with good and poor prognosis by Ki-67 proliferative index score in breast cancer. Methods. ERβ expression level (% of cells expressing the marker) in 68 breast tissue samples was quantified by immunofluorescence and flow cytometry. Primary antibodies to ERβ (clone 14C8, ab288) and secondary antibodies conjugated with DyLight650 (ab98729) were used. In the same samples, the Ki-67 expression level was assessed by the immunohistochemical method. Results. The ERβ and Ki-67 were detected in 100% breast tissue samples with high heterogeneity of the markers’ expression in different patients. Statistical analysis of good and poor prognosis in accordance with the Ki-67 proliferative index score (Ki-67≤20% and Ki-67&gt;20%) showed the prognostic value of the ERβ expression level of 50%. There was no association between the Ki-67 and ERβ expression levels in the same tumor sample (Spearman's rank correlation coefficient R=–0,16; P&gt;0,05). At the same time, high expression of ERβ≥50% was 2,3 times more frequently detected in the good vs poor prognostic group by Ki-67 — 41% vs 18%, P=0,02. Conclusion. The ERβ expression level ≥50% in the tumor can be considered as a factor of good prognosis of breast cancer.

Immunohistochemical Expression of Estrogen Receptor Beta in Urothelial Carcinoma of the Urinary Bladder

Immunohistochemical Expression of Estrogen Receptor Beta in Urothelial Carcinoma of the Urinary Bladder

Global Cerebral Ischemia Induces Short-Term Changes to Estrous Cycle Regularity and Alters Hypothalamic-Pituitary-Gonadal Axis Function

Global cerebral ischemia (GCI), which mimics cardiac arrest in humans, induces numerous functional alterations throughout the brain, but its impact on the hypothalamic-pituitary-gonadal (HPG) axis remains largely unknown. Importantly, the HPG axis modulates sex hormones and neuropeptides, such as estrogen and kisspeptin, as well as estrous cycle regularity. The goals of this study were to determine if estrous cycle regularity is affected by GCI and to characterize HPG axis functionality post-ischemia. Adult female Wistar rats underwent vaginal lavage for 2 weeks to confirm estrous cycle regularity before being subjected to GCI for 10 minutes or sham surgery. Estrous cycle regularity was monitored for 4 weeks following surgery, after which rats were euthanized. Immunofluorescence was used to detect kisspeptin receptors (Kiss1) and estrogen receptors alpha (ERα) and beta (ERβ) expression in the arcuate nucleus (ARC) of the hypothalamus, as well as the CA1 and dentate gyrus (DG) of the hippocampus. Following surgery, all sham subjects maintained a regular estrous cycle, whereas two thirds of ischemic rats presented a disrupted cycle following GCI (persistent diestrus, average length 13 days), before resuming regular cycling. T-test revealed a significant increase in Kiss1 receptors in the ARC of GCI rodents, as well as a trend for higher ERα expression in the CA1 of ischemic rats. Overall, our results highlight that while estrous cycle disruptions resolve within 2 weeks after the ischemic event, HPG axis dysregulation persists up to one month after GCI, hinting at possible long-term impacts on the reproductive axis.

Estrogen receptor beta expression in triple negative breast cancers is not associated with recurrence or survival

BackgroundTriple negative BCa (TNBC) is defined by a lack of expression of estrogen (ERα), progesterone (PgR) receptors and human epidermal growth factor receptor 2 (HER2) as assessed by protein expression and/or gene amplification. It makes up ~ 15% of all BCa and often has a poor prognosis. TNBC is not treated with endocrine therapies as ERα and PR negative tumors in general do not show benefit. However, a small fraction of the true TNBC tumors do show tamoxifen sensitivity, with those expressing the most common isoform of ERβ1 having the most benefit. Recently, the antibodies commonly used to assess ERβ1 in TNBC have been found to lack specificity, which calls into question available data regarding the proportion of TNBC that express ERβ1 and any relationship to clinical outcome.MethodsTo confirm the true frequency of ERβ1 in TNBC we performed robust ERβ1 immunohistochemistry using the specific antibody CWK-F12 ERβ1 on 156 primary TNBC cancers from patients with a median of 78 months (range 0.2–155 months) follow up.ResultsWe found that high expression of ERβ1 was not associated with increased recurrence or survival when assessed as percentage of ERβ1 positive tumor cells or as Allred > 5. In contrast, the non-specific PPG5-10 antibody did show an association with recurrence and survival.ConclusionsOur data indicate that ERβ1 expression in TNBC tumours does not associate with prognosis.

Abstract 3081: KDM1A/LSD1 inhibition enhances estrogen receptor beta mediated tumor suppression in ovarian cancer

Abstract Introduction: Ovarian cancer (OCa) is the deadliest of all gynecologic cancers. Recent studies suggest that OCa cells express estrogen receptor beta (ERb), which functions as a tumor suppressor. However, ERb expression decreases during tumor progression and under the selection pressure of chemotherapy; this decrease occurs via epigenetic mechanisms and is inversely correlated with OCa progression. Lysine-specific histone demethylase 1A (KDM1A/LSD1), an epigenetic modifier, is highly overexpressed in OCa. However, it is not known if KDM1A regulates ERb expression and its corresponding tumor suppressor functions. In this study, we explored the hypotheses that KDM1A inhibits ERb expression and function and that ERb-mediated tumor suppression in OCa is enhanced by KDM1A inhibition. Methods: Transduction of KDM1A-specific shRNA or gRNA was used to generate KDM1A knockdown (KD) or knockout (KO) cells, respectively. Cell viability, survival, apoptosis, and invasion assays were used to determine the impact of KDM1A knockdown or inhibitor therapy on ERb agonist response in established and patient-derived OCa cells. Mechanistic studies were conducted using RNA-seq, discovery proteomics, chromatin immunoprecipitation (ChIP), co-immunoprecipitation (co-IP), proximity ligation, ERE-Luc reporter, RT-qPCR, and western blot analysis. The efficacy of the combination of KDM1A inhibitor and ERb agonist therapy was investigated using patient-derived explant (PDeX) models. In vivo efficacy of KDM1A inhibitor and ERb agonist was determined using orthotopic OCa and patient-derived xenograft (PDX) murine models. Results: Analysis of TCGA datasets revealed a negative correlation between ERb and KDM1A expression in OCa patients. ChIP experiments showed that KDM1A is enriched at the ERb 0N promoter and that KDM1A KD, KO, or inhibition specifically upregulates the expression of ERb isoform 1. Co-IP and proximity ligation assays demonstrated that KDM1A interacts with ERb. Combining the ERb agonist LY500307 with KDM1A inhibitor NCD38 decreased the cell viability, survival, and invasion of both established and patient-derived primary OCa cells while increasing apoptosis. KDM1A KD- or inhibition potentiated the efficacy of ERb agonist in inducing ERb target gene expression via altered histone methylation marks. RNA-seq and proteomic analysis demonstrated that KDM1A KO and ERb agonist treatment increased the expression of apoptotic genes and downregulated cell cycle, EMT, and DNA repair genes. Importantly, combination therapy significantly reduced OCa cell proliferation in PDeX models and reduced in vivo tumor growth in orthotopic and PDX models. Conclusions: Our findings demonstrate that KDM1A inhibition enhances ERb expression and tumor suppressive functions, suggesting that combination therapy of a KDM1A inhibitor and ERb agonist may be a promising therapeutic option for treating OCa. Citation Format: Prabhakar P. Venkata, Sridharan Jayamohan, Yi He, Salvador Alejo, Jessica D. Johnson, Uday P. Pratap, Suryavathi Viswanadhapalli, Susan Weintraub, Rajeshwar R. Tekmal, Ratna K. Vadlamudi, Edward Kost, Gangadhara R. Sareddy. KDM1A/LSD1 inhibition enhances estrogen receptor beta mediated tumor suppression in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3081.

Immunohistochemical Expression (IE) of Oestrogen Receptors in the Intestines of Prepubertal Gilts Exposed to Zearalenone.

This study was conducted to determine if a low monotonic dose of zearalenone (ZEN) affects the immunohistochemical expression (IE) of oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERβ) in the intestines of sexually immature gilts. Group C (control group; n = 18) gilts were given a placebo. Group E (experimental group; n = 18) gilts were dosed orally with 40 μg ZEN /kg body weight (BW), each day before morning feeding. Samples of intestinal tissue were collected post-mortem six times. The samples were stained to analyse the IE of ERα and Erβ in the scanned slides. The strongest response was observed in ERα in the duodenum (90.387-average % of cells with ERα expression) and in ERβ in the descending colon (84.329-average % of cells with ERβ expression); the opposite response was recorded in the caecum (2.484-average % of cells with ERα expression) and the ascending colon (2.448-average % of cells with ERα expression); on the first two dates of exposure, the digestive tract had to adapt to ZEN in feed. The results of this study, supported by a mechanistic interpretation of previous research findings, suggest that ZEN performs numerous functions in the digestive tract.

Estrogen receptor beta expression in colitis-associated carcinoma in comparison with sporadic colonic tumor: An immunohistochemical study.

The rate of ulcerative colitis (UC)-related colorectal cancer (colitis-associated carcinoma) is increasing. Estrogen receptor (ER) beta expression has been studied separately in patients with sporadic colorectal cancer and those with colitis-associated carcinoma. However, no study has compared the expression in both of these cancer types. The present study aimed to evaluate the relationship between colitis-associated carcinoma and ERs and assess whether the expression of ER beta influences cell proliferation. This study included 45 surgically operated colitis-associated carcinomas, 43 high-grade dysplasias, 34 low-grade dysplasias, 36 sporadic colorectal cancers, 44 high-grade adenomas, and 34 low-grade adenomas. ER beta expression was evaluated with immunohistochemistry. Colitis-associated carcinoma showed significantly lower ER beta immunoexpression than sporadic colorectal lesions and high- and low-grade dysplasia. In seven colitis-associated carcinoma harboring both intensity score 3 (strong immunoexpression) and score 1 (weak immunoexpression) areas, the correlation among ER beta intensity, Ki-67, and p21 labeling index was assessed; an area with an ER beta intensity score of 3 showed a higher Ki-67 labeling index than that with score 1. In four out of the seven lesions, p21 labeling index was higher in the area of ER beta score 1 than in that of ER beta score 3. The data suggest that ER beta expression is an accelerating factor in colorectal tumors. This association may be lower in colitis-associated carcinoma than in sporadic colorectal cancer.

Evaluation of tooth eruption rate of incisor teeth in rats with estrogen deficiency.

To assess the influence of estrogen deficiency on tooth eruption rate (TER) and gene expression of estrogen receptor alpha and beta (ERα and ERβ) in the odontogenic region of teeth with continuous formation in a rat model. Ovariectomies (OVX; n = 25) and sham surgeries (SHAM; n = 25) were performed in female Wistar rats when animals were 25days old. The TER of the lower incisors, both in impeded (hyperfunction condition) and unimpeded (trimmed incisal edge-hypofunction condition) conditions, was evaluated using standardized digital photographs acquired every 48-72h for 3weeks (35th-53rd day of life), using a camera coupled to a stereomicroscope. Quantitative real-time PCR was performed to evaluate the relative gene expression of ERα and ERβ in the odontogenic region. The OVX group showed a significant reduction in TER when compared to the SHAM group, only in the impeded condition (p = 0.03). There was no statistically significant difference between the groups in ERα gene expression (p = 0.33). ERβ showed a significantly higher gene expression in the OVX group (p ≤ 0.05). Estrogen deficiency decreases TER in teeth under impeded condition. Estrogen deficiency also increases ERβ gene expression in the odontogenic region of teeth with continuous formation. Hormonal disturbances affecting estrogen levels can cause alterations in dental formation and teeth eruption.

Longitudinal effects of estrogen on mandibular growth and changes in cartilage during the growth period in rats

Estrogen is a steroid hormone that induces skeletal growth and affects endochondral ossification of the long tubular bone growth plate during the growth period. However, the effects of estrogen on endochondral ossification of the mandibular condylar cartilage are unclear. In this study, ovariectomized Wistar/ST rats were used to investigate the longitudinal effects of estrogen on mandibular growth. The rats were administered different doses of estrogen. Longitudinal micro-computed tomographic scanning, histological staining and ELISA on plasma growth hormone were performed to examine the effects of estrogen on mandibular growth. The results showed that mandibular growth was suppressed throughout the growth period by estrogen in a dose-dependent manner. In addition, long-term administration of a high dose of estrogen to the rats resulted in significant increase in growth hormone throughout the growth period, significant circularization of cell nuclei in the proliferative layer, intensely staining cartilage matrix in the subchondral bone, and significant suppression of estrogen receptor (ER) alpha and beta expression in the mandibular cartilage. However, regardless of estrogen concentration, in the posterior part of the mandibular cartilage, ER expression extended to both the hypertrophic and proliferative layers. These results indicate that estrogen suppresses mandibular growth throughout the growth period. Additionally, it influences endochondral ossification via its effect on ERs.

Estradiol and zinc-doped nano hydroxyapatite as therapeutic agents in the prevention of osteoporosis; oxidative stress status, inflammation, bone turnover, bone mineral density, and histological alterations in ovariectomized rats.

Osteoporosis (OP) is a serious health problem, and the most popular therapeutic strategy for OP is hormone replacement (estrogen); however, it increases the risk of reproductive cancers. Hydroxyapatite (HA) nanoparticles have a similar chemical structure to the bone mineral component and can be used as a new remedy for OP. This study was designed to investigate the osteoporosis-protective potential of nano zinc hydroxyapatite (ZnHA-NPs) and/or estradiol (E2) combined therapy. A total of 35 adult female rats were assigned into five groups (n = 7): 1) control group; 2) ovariectomized group (OVX); 3) OVX received oral estradiol replacement therapy (OVX/E2); 4) OVX received ZnHA replacement therapy (OVX/ZnHA); and 5) OVX received both estradiol and ZnHA-NPs combined therapy (OVX/E2+ZnHA). After 3 months of treatment, serum bone markers and estrogen level, oxidative/antioxidant, and inflammatory cytokines were determined. Additionally, femoral expression of estrogen receptors alpha and beta (ESR1; ESR2), receptor activator of nuclear factor-kappa B (RANKL) ligand, osteoprotegerin (OPG), bone mineral density (BMD), histological alterations, and immunohistochemical expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) were assessed. ALP, PINP, Ca, and P concentrations improved significantly (p < 0.05) in all treatment groups, especially in the OVX/E + ZnHA group. MDA and NO were higher in OVX rats, while SOD activity and GSH were lower (p < 0.05). E2 alone or with ZnHA-NPs restored the estimated antioxidant molecules and cytokines toward normal levels in OVX rats (p < 0.05). On the other hand, E2 and ZnHA increased OPG and OC expression in femurs while decreasing ESR1, ESR2, and NF-kB expression (p < 0.05). The combination treatment was superior in the restoration of normal femoral histoarchitecture and both cortical and trabecular BMD (p < 0.05). Overall, the combined therapy of OVX/E2+ZnHA was more effective than the individual treatments in attenuating excessive bone turnover and preventing osteoporosis.

Expression of Estrogen Receptor Beta 2 in Laryngeal Cancer and Its Relationship with Lymph Node Metastasis

Expression of Estrogen Receptor Beta 2 in Laryngeal Cancer and Its Relationship with Lymph Node Metastasis

Abstract 891: Therapeutic targeting of ovarian cancer stem cells using estrogen receptor beta agonist

Abstract Background: Ovarian cancer (OCa) is the deadliest gynecologic cancer. Emerging studies suggest that ovarian cancer stem cells (OCSCs) contribute to tumor relapse and chemotherapy resistance. Recent studies demonstrate that OCa cells express estrogen receptor beta (ERβ), which functions as a tumor suppressor. However, the status of ERβ expression in OCSCs and the therapeutic utility of ERβ agonist LY500307 for targeting OCSCs remain unknown. In this study, we tested the hypothesis that OCSCs express ERβ and that treatment with ERβ agonist reduces stemness and promotes apoptosis of OCSCs. Methods: We isolated subpopulations of OCSCs from SKOV3, A2780, and patient-derived ascites cells using ALDEFLUOR kit and examined the expression of ERβ in OCSCs using RT-qPCR. The effect of ERβ agonist LY500307 on OCSCs was examined utilizing cell viability, cell cycle, sphere formation, self-renewal, and apoptosis assays. Mechanistic studies were conducted using RNA-seq, RT-qPCR, and Western blot analysis. The efficacy of LY500307 on the tumor-initiating capacity of OCSCs was determined via in vivo limiting dilution assay studies using orthotopic intrabursal xenograft murine models. Results: RT-qPCR assay showed that ERβ, particularly ERβ isoform 1, is highly expressed in OCSCs compared to non-OCSCs. ERβ agonist LY500307 significantly reduced the viability of OCSCs compared to non-OCSCs. Treatment of OCSCs with LY500307 significantly reduced the sphere formation and self-renewal of OCSCs. Further, LY500307 treatment resulted in G2/M cell cycle arrest and promoted the apoptosis of OCSCs. Mechanistic studies using RNA-seq analysis demonstrated that ERβ agonist treatment resulted in the modulation of pathways related to cell cycle and apoptosis. Western blots and RT-qPCR assays confirmed the upregulation of genes involved in apoptosis and cell cycle arrest, such as FDXR and CDKN1A. Importantly, treatment of LY500307 significantly attenuated the tumor-initiating capacity of OCSCs in orthotopically implanted OCa murine models. Conclusions: Our results demonstrate that ERβ agonist LY500307 is highly efficacious in reducing the stemness and promoting apoptosis of OCSCs and may serve as a novel therapeutic agent in treating OCa Citation Format: Yi He, Salvador Alejo, Prabhakar P. Venkata, Jessica D. Johnson, Ilanna Loeffel, Julie Ann Martel, Uday P. Pratap, Suryavathi Viswanadhapalli, Rajeshwar R. Tekmal, Ratna K. Vadlamudi, Edward Kost, Gangadhara R. Sareddy. Therapeutic targeting of ovarian cancer stem cells using estrogen receptor beta agonist [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 891.