Intricate roles of estrogen and estrogen receptors in digestive system cancers:a systematic review

Gender disparities are evident across different types of digestive system cancers,which are typically characterized by a lower incidence and mortality rate in females compared to males.This finding suggests a potential protective role of female steroid hormones,particularly estrogen,in the development of these cancers.Estrogen is a well-known sex hormone that not only regulates the reproductive system but also exerts diverse effects on non-reproductive organs mediated through interactions with estrogen receptors(ERs),including the classic(ERαand ERβ)and non-traditional ERs[G protein-coupled estrogen receptor(GPER)].Recent advances have contributed to our comprehension of the mechanisms underlying ERs in digestive system cancers.In this comprehensive review we summarize the current understanding of the intricate roles played by estrogen and ERs in the major types of digestive system cancers,including hepatocellular,pancreatic,esophageal,gastric,and colorectal carcinoma.Furthermore,we discuss the potential molecular mechanisms underlying ERα,ERβ,and GPER effects,and propose perspectives on innovative therapies and preventive measures targeting the pathways regulated by estrogen and ERs.The roles of estrogen and ERs in digestive system cancers are complicated and depend on the cell type and tissue involved.Additionally,deciphering the intricate roles of estrogen,ERs,and the associated signaling pathways may guide the discovery of novel and tailored therapeutic and preventive strategies for digestive system cancers,eventually improving the care and clinical outcomes for the substantial number of individuals worldwide affected by these malignancies.

Ulcerative colitis: From inflammation to cancer. Do estrogen receptors have a role?

Ulcerative colitis(UC) is a condition at increased risk for colorectal carcinoma(CRC) development. Nowadays, screening and follow-up programs are routinely performed worldwide to promote the early detection of CRCs in subjects with well known risk factors(extent, duration and severity of the disorder). The diffusion of these procedures is presumably the main reason for the marked reduction of cancer incidence and mortality in the course of UC. In addition, chemoprevention has been widely investigated and developed in many medical fields, and aspirin has shown a preventive effect against CRC, while mesalazine has been strongly invoked as a potential chemopreventive agent in UC. However, available studies show some limitations due to the obvious ethical implications of drug withdrawal in UC in order to design a control group. The estrogenreceptors(ER) alpha/beta balance seems to have a relevant influence on colorectal carcinogenesis and ER beta appears to parallel apoptosis, and hence an anticarcinogenic effect. Phytoestrogens are compounds acting as ER beta agonists and have shown a promising chemopreventive effect on sporadic as well as genetically inherited CRC. There is evidence suggesting a role for ERs in UC-related carcinogenesis. In this perspective, since these substances can be considered as dietary supplements and are completely free from side effects, phytoestrogens could be an interesting option for CRC prevention, even when the disease is a consequence of long-term chronic inflammation, as in the course of UC. Further studies of their effects are warranted in both the basic research and clinical fields.

Epithelial turnover in duodenal familial adenomatous polyposis: A possible role for estrogen receptors?

AIM: To investigate estrogen receptors expression in duodenal familial adenomatous polyposis (FAP) and any relationship with epithelial proliferation/apoptosis markers.METHODS: Twenty-two patients affected by FAP undergoing duodenal resection for malignancies were recruited. Controls were 15 healthy subjects undergoing endoscopy for dyspeptic symptoms. ER-α, ER-α, Ki-67, TUNEL and caspase 3 expression (labeling index: percentage of positive cells) were evaluated by immunohistochemistry or immunofluorescence and examined by light or confocal microscopy. Samples were assigned to four groups: normal tissue, low (LGD) and high-grade dysplasia (HGD), adenocarcinoma (AC). One-way analysis of variance, corrected by Bonferroni’s test, and Pearson’s correlation test were applied for statistical analysis.RESULTS: ER-beta showed a progressive decline: normal tissue (23.5 ± 4.9), LGD (21.1 ± 4.8), HGD (9.3 ± 3.5), AC (7.1 ± 3.1). The normal tissue of FAP subjects expressed ER-beta like the controls (23.9 ± 6.2). Conversely, ER-α showed a progressive increase from normal tissue (24.8 ± 5.6) to AC (52.0 ± 8.2); the expression in normal tissue was similar to controls (22.5 ± 5.3). Ki67 demonstrated a statistically significant progressive increase at each disease stage up to AC. TUNEL did not reveal differences between controls and normal tissue of FAP subjects, but progressive decreases were observed in LGD, through HGD to AC. Pearson’s correlation test showed a direct relationship between ER-β and TUNEL LI (r = 0.8088, P < 0.0001). Conversely, ER-α was inversely correlated with TUNEL LI (r = - 0.7257, P < 0.0001). The co-expression of ER-β and caspase 3 declined progressively from normal to neoplastic tissue.CONCLUSION: This study confirmed that ER-β is strongly decreased in duodenal FAP carcinomas, declining in a multiple step fashion, thereby suggesting a putative anti-carcinogenic effect. ER-α showed the opposite trend. ER-β/caspase 3 co-expression suggests this hormone’s possible involvement in apoptosis. Hormonal influences in FAP duodenal tumorigenesis, and modulation of these as a possible chemoprevention strategy, may be a promising approach.

The Prognostic Significance of a Combined Determination of Cathepsin D and Estrogen Receptors in Breast Carcinomas with Positive Axillary Lymph Nodes

OBJECTIVE The aim of this study was to investigate the correlation between cathepsin D （Cath-D） and estrogen receptor （ER）expression in breast cancer tissue and to explore the prognostic significance of their combined determination in breast carcinoma patients with positive axillary lymph nodes. METHODS One hundred and thirty-eight cases of breast carcinoma were examined by immunohistochemistry （IHC） and the results relating to patient follow-up analyzed. RESULTS The overall 5-year disease-free survival rate （DFS） was 60.9% （84/138） in the series. The positive rate of Cath-D expression in the tumor cells was 55.07% and the positive ER staining was 51.4%. A definite significant negative correlation was found between the positive rates for Cath-D and ER （r=-0.294, P=0.001） The Cath-D expression for the cases in clinical Stage Ⅱ, ≥10 positive-node and recurrence or distant metastasis, was higher than that those cases in clinical Stage II with fewer node-metastasis and with 5 year DFS （X^2=13.926, P=0.000; X^2=13.070, P=0.001; X^2=10.545, P=0.001）. However, there was no significant difference of Cath-D expression between 2 groups of patients with different ages or among the different histopathologic types of the nonspecific invasive carcinoma. In the combined examination of Cath-D and ER, the cases that were ER （＋） and Cath-D （-） had the highest 5-year DFS compared to other situations. In contrast, the cases that were reversed in expression, ie, ER（-） and Cath-D（＋）, had a lower 5-year DFS. There was a significant difference between the 2 conditions （X2=18.675, P=0.000）. CONCLUSION A combined determination and analysis of Cath-D and ER expression may be more useful to establish a prognosis than the biological characteristics of carcinomas with positive lymph nodes.

The expression of estrogen receptors in thyroid cancer and its significance

Objective The study aimed to detect the expression of estrogen receptors(ERs) in thyroid cancer and investigate the correlation between their expression and clinical features and different pathological types.Methods The expression of ERs in 56 samples of thyroid cancer tissues was detected by an immunochemical approach. The expression of ERs in thyroid cancer tissues and different pathological types were analyzed using the χ~2 test. Results The number of cases with positive expression of ER in thyroid cancer tissues was 36. The number of papillary thyroid cancers(PTCs) was 48, with positive expression of ERs in 32 cases. The number of follicular thyroid cancers was 4, with positive expression of ERs in 2 cases. The number of medullary thyroid cancers was 4, with negative expression of ERs in all cases. The difference between the expression and different pathological types showed statistical significance. The expression of ERs showed no correlation with sex, age, or TNM stage, with no statistical significance. However, the expression of ERs was correlated with metastasis of lymph nodes, which had statistical significance. The expression of ERs was negatively correlated with pathological types and metastasis of lymph nodes. The correlated coefficient index was –0.313 and –0.334, respectively. Conclusion The expression of ERs showed no correlation with sex, age, or TNM stage, but was negatively correlated with pathological types and metastasis of lymph nodes.

PRODUCTION AND APPLICATION OF MOUSE ANTISERUM TO HUMAN ESTROGEN RECEPTORS

A polyclonal antibody to peptide containign 15 amino acids and corresponding to reion-D of human estrogen receptors(hERD)was obtained in mice by immunization with the coupler of peptide and KLH. Usuig this antiserum,the ER stathe of paraffin-embeded sections of 95 human breast carcinomas were studied. The corresponding rate for determination of ER status between immunohistochemical staining(IHC)and dextran coated charcoal(DCC)assay was 89. 5%. The concordance for semiquantitative grades was 69.3%. In addition, in situ hybridization(ISH)of 15 frozen sections of same sample using digoxigenin labeled dUTP to identify the expreesion of ER mRNA for confirming the 1HC also be used. This technique revealed more specific,sensitive and convenient than DCC.The results of ISH were fully consistent with IHC(100%). Above results show that the mouse antsierum hERD obtained in this study is specific and sensitive for IHC assay of ER and IHC is a valuable adjunct and/or alternative to the biochemical method for determination of the ER status of breast cancer.

Low-molecular-weight estrogenic phytoprotein suppresses osteoporosis development through positive modulation of skeletal estrogen receptors

Age-related osteoporosis is a metabolic skeletal disorder caused by estrogen deficiency in postmenopausal women.Prolonged use of anti-osteoporotic drugs such as bisphosphonates and FDA-approved anti-resorptive selective estrogen receptor modulators(SERMs)has been associated with various clinical drawbacks.We recently discovered a low-molecular-weight biocompatible and osteoanabolic phytoprotein,called HKUOT-S2 protein(32 kDa),from Dioscorea opposita Thunb that can accelerate bone defect healing.Here,we demonstrated that the HKUOT-S2 protein treatment can enhance osteoblasts-induced ossification and suppress osteoporosis development by upregulating skeletal estrogen receptors(ERs)ERα,ERβ,and GPR30 expressions in vivo.Also,HKUOT-S2 protein estrogenic activities promoted hMSCs-osteoblasts differentiation and functions by increasing osteogenic markers,ALP,and RUNX2 expressions,ALP activity,and osteoblast biomineralization in vitro.Fulvestrant treatment impaired the HKUOT-S2 protein-induced ERs expressions,osteoblasts differentiation,and functions.Finally,we demonstrated that the HKUOT-S2 protein could bind to ERs to exert osteogenic and osteoanabolic properties.Our results showed that the biocompatible HKUOT-S2 protein can exert estrogenic and osteoanabolic properties by positively modulating skeletal estrogen receptor signaling to promote ossification and suppress osteoporosis.Currently,there is no or limited data if any,on osteoanabolic SERMs.The HKUOT-S2 protein can be applied as a new osteoanabolic SERM for osteoporosis treatment.

Regulation of estrogen receptors α and β in human breast carcinoma by exogenous leptin in nude mouse xenograft model

Background It is essential to clarify the interactions of hormones during the progression of human breast cancer. This study examined the effects of exogenous human leptin on estrogen receptor （ER） α and β in human breast tumor tissue in a nude mouse xenograft model. Methods We created nude mice xenografts of MCF-7 human breast cancer cells, and randomly divided them into an experimental group and a control group. The mice in experimental group were injected subcutaneously around tumors with human leptin, while the control group were injected with the same dose of normal saline. A real-time RT-PCR assay was developed to quantify the mRNA of ERα, β in the tumor tissues. Western blotting analyses were used to assess the relative quantities of the ERα , β proteins. Results Leptin-treated xenografted nude mice were successfully established. The amount of ERa mRNA was significantly higher in the leptin group than in the control group （P 〈0.01）, while the amount of ERβ mRNA was significantly lower in the leptin group than in the control group （P 〈0.01）. Western blotting analyses revealed that the ERa protein level was significantly higher in the leptin group than in the control group （P 〈0.01）, while the ERβ protein level was significantly lower in the leptin group than in the control group （P 〈0.01）. Conclusions Nude mouse xenograft model can be safely and serviceably treated with human leptin by subcutaneous injections around tumor. ERα, β were both targets of leptin in breast cancer. Leptin can up-regulate the expression of ERa and down-regulate the expression of the ERβ in human breast tumor.

Er-xian ameliorates myocardial ischemia-reperfusion injury in rats through RISK pathway involving estrogen receptors

Curculigo orchioides(CUR)and Epimedium(EPI)are traditional Chinese medicines with estrogen-like biological activity,called Xianmao and Xianlingpi(Er-xian)in Chinese.However,whether Er-xian exerts protective effects on myocardial ischemia-reperfusion injury(MIRI)is unknown.This study aimed to investigate the cardioprotective effects of Er-xian preconditioning against MIRI and the underlying mechanisms.CUR or EPI was administered intragastrically to aged female rats as a monotherapy or combination therapy.2 weeks later,a rat MIRI model was established.Myocardial infarction size,myocardial morphology,cTnT,cell apoptosis rate,intracellular calcium concentration,mitochondrial permeability transition pore(MPTP)opening and reperfusion injury salvage kinase(RISK)signaling pathway molecules were observed after the surgery.To evaluate the mechanisms of Er-xian,estrogen receptors antagonists ICI 182780 and G15 were used.In this study,Er-xian notably alleviated myocardial tissue damage,maintained mitochondrial morphology,reduced infarct size and cardiac markers,and increased sera levels of E2.Moreover,Er-xian inhibited calcium overload and mPTP opening,and decreased cardiomyocyte apoptosis.We found that the dual therapy of CUR and EPI elicited more noticeable results than CUR or EPI monotherapy.The significant protective effects of Er-xian on ischemia-reperfusion myocardium were attributed to the up-regulation of AKT,ERK1/2 and GSK-3βphosphorylation levels.The cardioprotective effects of Er-xian were significantly reduced after estrogen receptor blockade,especially GPER30.These results indicate that Er-xian attenuates MIRI through RISK signaling pathway and estrogen receptors are the critical mediators.

Unveiling the effect of estrogen receptors in alcoholic liver disease:A novel outlook

Alcoholic liver disease(ALD)has a multifaceted development,progressing from alcoholic steatosis to alcoholic hepatitis and ultimately to alcoholic cirrhosis,irreversible liver damage that can even result in hepatocellular carcinoma.The prevalence of ALD is increasing globally,particularly among middle-aged adults.Gender-based studies have revealed that ALD affects more men;however,disease progression differs between men and women.Despite this,the molecular understanding of alcohol-induced liver injury among genders and its association with changes in sex hormone metabolism,particularly with estrogen and estrogen receptors(ERs)in ALD,remains poor.This review focuses on experimental and human studies describing alcohol and its association with estrogen metabolism and signaling via ERs.Chronic alcohol consumption affects the immune response,and whether estrogen has any contributory effect remains inadequately studied.This review also discusses various therapeutic approaches currently in use and future approaches that can affect the response or progression via estrogen signaling.The role of gender on alcohol consumption and its association with steroid hormones must be elucidated for a better understanding of the pathogenesis of ALD,the development of effective therapeutic approaches,and better disease management in both men and women,as ALD remains a major public health concern.

Expression of Progesterone and Estrogen Receptors in Human Renal Cell Carcinoma

Progesterone receptor(PR) and estrogen receptor(ER) were investigated in 29 specimens of renal cell carcinoma (RCC) and its autologous kidneys, 12 samples of control kidnerys with high sensitive and specific enzymelabelled histochemical techniques. The positive expression rates of PR in RCC, its autologous kidneys and control kidneys were 31.0%, 82.8% and 83.3% respectively, while the positive expression rates of ER of those tissues were 58.6%, 79.3% and 83.3%, respectively. It showed that the positive rate and the value of PR and ER in RCC were significantly less than those determined in the autologous kidneys and normal tissues(P<0.05) and no significant differences of PR and ER were found between autologous and normal kidneys(P>0.05). The level and positive rate of PR in stage Ⅰ were higher than those in stage Ⅱ to Ⅳ of RCC tissues (P<0.05). There was no relationship between the status of PR, ER and patient sex(P>0.05). Expression of PR in RCC had correlation to Robson stage closely. The positive rate of PR may be treated as a prognostic factor because it decreased as the stage rose. Our result provided an experimental basis for the application of hormonal therapy in RCC and emphasized that patients who may be benefited from hormonal therapy must have sufficient hormone receptors.

Correlations between Expression of Estrogen and Androgen Receptors and the Clinical Characteristics of Prolactinoma~*

Objective： To study the correlations between estrogen receptor （ER） and androgen receptor （AR） and the clinical presentations of prolactinoma and investigate the effect of ER and AR expression on the pathogenesis of prolactinoma in sexual difference. Methods： The clinical data of 30 patients who had undergone transsphenoidal operations in Tongji Hospital from December 2000 to December 2001 were reviewed retrospectively. The clinical information included sex, age, serum-prolactin, size, tumor invasiveness, history of use of bromocriptine and frequency of recurrence. In 20 out of the 30 patients, the ER and AR expression was detected by using immunohistochemistry method. With help of Chi-square test, the relationship between ER, AR and the clinical presentations was analyzed. Results： The statistical values revealed that there was no significant correlation between the ER and AR expression levels with the clinical presentations such as sex, age, tumor size or tumor invasiveness among the 20 patients studied （P〉0.05）. Conclusion： The expression of ER or AR is not influenced by the clinical data of prolactinoma such as sex, age, tumor diameter or extent of tumor invasiveness. The tumor is more aggressive in males than in females. In maroadenoma or tumor with hyperprolactineamia （〉200 ng/mL） simple surgical treatment can＇t successfully cure the prolactinoma. Post-operative bromocriptine therapy can＇t be determined by the sex of the patients, but is greatly related to the tumor size and serum-prolactin level before operation.

Effects of estrogen and tibolone on bladder histology and estrogen receptors in rats

Background Estrogen deficiency causes atrophic changes within the urogenital tract, and is associated with urinary symptoms. The purpose of this study was to investigate the effects of estrogen and tibolone on bladder histology, and the changes of estrogen receptor a and β （ERα and β） protein expression in the detrusor muscle.Methods Forty female rats were separated into four groups of ten each. They received a sham operation （Sham）, ovariectomy （Ovx）, ovariectomy plus estrogen replacement （Ovx＋E）, or ovariectomy plus tibolone treatment （Ovx＋T）. After 12 weeks each rat was anesthetized and the bladders were removed. The bladders＇ ultra structure, collagen fiber （CF） to smooth muscle（SM） ratio and ER subtypes were studied. Statistical analyses were performed using the one-way analysis of variance test. Results Ovx resulted in significant degeneration in bladder ultra structure; however, estrogen and tibolone reversed those changes. Ovx increased the CF/SM ratio, estrogen and tibolone resulted in an increase. Two estrogen receptors （ERs） were expressed in the bladder detrusor, with ERβ the main subtype. Ovx resulted in up-regulation of ERα and down-regulation of ERβ. With estrogen and tibolone treatment, ERβ showed a significant increase but ERα showed no significant difference compared with Ovx. Conclusions Estrogen deficiency deteriorates bladder ultra structure and histology. Supplementary estrogen can improve bladder function which may be due to inhibition of collagen hyperplasia and increased SM density. ERβ has an important role in mediating estrogen function in the bladder. Tibolone has a mild estrogenic action and has an effect on bladder function and structure to some degree.

Effects of Transdermal Estrogen Therapy on Expressions of Estrogen Receptors and T-lymphocyte Apoptosis in Surgically Menopausal Women

Studies have demonstrated estrogen replacement therapy can improve the life quality of surgically menopausal women. However, the mechanisms in this process remain poorly defined. Here we show the effect of transdermal estrogen therapy on expressions of estrogen receptors and T-lymphocyte apoptosis in surgically postmenopausal women. Fifteen surgically menopausal women, 15 naturally menopausal women and 15 young women were chosen in our studies. Peripheral vein blood was collected and serum E2 and FSH levels were assessed using ACCESS. T-lymphocyte apoptosis and the expressions of Fas, FasL and ER subtypes α and β were determined. The serum E2 levels of surgically menopausal woman were significantly higher, and the ＂Improved Kupperman Index＂ and the scores of ＂Menopause Specific Quality of Life Questionnaire＂ in surgically menopausal women were significantly low after ERT. The rates of T-lymphocyte apoptosis and FasL expression in surgically menopausal women were decreased after ERT, but the difference was not significant. The expressions of ERa and ERβ in two menopausal groups were significantly lower than those of the young group. They were both significantly up-regulated after 3 months of ERT. Transdermal ERT could significantly upregulate the serum E2 level, could improve menopausal symptoms and life quality of surgically menopausal women and upregulate ERa and ERβ expressions on T lymphocytes, especially ERp. Thus, the low dose of transdermal ERT may have a protective effect on menopausal women＇s immune function and aging.

Effects of Mifepristone Compound on the Receptors of Estrogen and Progesterone in Early Pregnancy Deciduas

To examine the effect of mifepristone compound (mifepristone + anor- drin) on estrogen receptor (ER) and progesterone receptor (PR) in early pregnancy decidua. Materials & Methods A Controlled study was carried out among 60 normal early pregnant volunteers (≤49d) in the department of obstetric and gynecology of Peking Union Medical Hospital. The concentrations of ER and PR were measured by radio- ligand and were compared with the control subjects after oral administration of mifepristone or mifepristone compound in different doses. Results The concentration of PR decreased while that of ER increased significantly in the decidua from all subjects administrated with mifepristone compound. We also found the concentration of EcR in Group 5 (mifepristone 30 mg + AF-53 5 mg) was the highest among 6 groups. The compound may be in favor of estrogen's action on endometrium. Conclusion The results indicate that mifepristone compound with AF- 53 has a coordi- nated function and can change the proportion of PR and ER. Hence, it can facilitate abortion. The compound dose of mifepristone 30 mg + AF-53 5mg is in favor of the endometrium recovering.

Clinical Significance of Estrogen and Progesterone Receptors Assays in Pancreatic Carcinoma

Cyochemical methods for demonstrating estrogen receptor (ER) and progesterone receptor (PgR)within pancreas-cancer cells showed positive reation of ER or/and PgR in 4 out of 8 pancreatic carcinomas.This result suggested that sex hormone might be closely linked to pancreatic cancer.Pancreatic carcinoma could be considered a hormoneresponsive-neoplasm. The hormone migh be a cause influencing the growth of pancreatic carcinoma in association with receptors described. Endocrine therapy would be a treatment of choice for pancreatic carcinoma.

17β-Estradiol,through activating the G protein-coupled estrogen receptor,exacerbates the complication of benign prostatic hyperplasia in type 2 diabetes mellitus patients by inducing prostate proliferation

Benign prostatic hyperplasia(BPH)is one of the major chronic complications of type 2 diabetes mellitus(T2DM),and sex steroid hormones are common risk factors for the occurrence of T2DM and BPH.The profiles of sex steroid hormones are simultaneously quantified by LC-MS/MS in the clinical serum of patients,including simple BPH patients,newly diagnosed T2DM patients,T2DM complicated with BPH patients and matched healthy individuals.The G protein-coupled estrogen receptor(GPER)inhibitor G15,GPER knockdown lentivirus,the YAP1 inhibitor verteporfin,YAP1 knockdown/overexpression lentivirus,targeted metabolomics analysis,and Co-IP assays are used to investigate the molecular mechanisms of the disrupted sex steroid hormones homeostasis in the pathological process of T2DM complicated with BPH.The homeostasis of sex steroid hormone is disrupted in the serum of patients,accompanying with the proliferated prostatic epithelial cells(PECs).The sex steroid hormone metabolic profiles of T2DM patients complicated with BPH have the greatest degrees of separation from those of healthy individuals.Elevated 17β-estradiol(E2)is the key contributor to the disrupted sex steroid hormone homeostasis,and is significantly positively related to the clinical characteristics of T2DM patients complicated with BPH.Activating GPER by E2 via Hippo-YAP1 signaling exacerbates high glucose(HG)-induced PECs proliferation through the formation of the YAP1-TEAD4 heterodimer.Knockdown or inhibition of GPER-mediated Hippo-YAP1 signaling suppresses PECs proliferation in HG and E2 co-treated BPH-1 cells.The anti-proliferative effects of verteporfin,an inhibitor of YAP1,are blocked by YAP1 overexpression in HG and E2 co-treated BPH-1 cells.Inactivating E2/GPER/Hippo/YAP1 signaling may be effective at delaying the progression of T2DM complicated with BPH by inhibiting PECs proliferation.

Comprehensive Analysis of Estrogen Receptor 1 Dysregulation in Liver Hepatocellular Carcinoma: Implications for Prognosis and Therapeutic Targeting - A Secondary Publication

The study investigates the expression pattern and regulatory mechanisms of estrogen receptor 1 (ESR1) in liver hepatocellular carcinoma (LIHC) through comprehensive bioinformatics analysis. Utilizing UALCAN and GEPIA2 databases, significant down-regulation of ESR1 expression is observed in LIHC samples compared to normal controls, indicating its potential role in tumor progression. Further analysis reveals consistent down-regulation across different clinical variables including patient age, gender, race, and various stages of LIHC, affirming the regulatory role of ESR1 in tumor development and progression. Additionally, promoter methylation analysis demonstrates hypermethylation of ESR1 in LIHC samples, negatively correlating with its expression. This association persists across different clinical parameters, emphasizing the inverse relationship between ESR1 methylation and expression levels. Survival analysis indicates that up- regulation of ESR1 is associated with better overall survival, suggesting its potential as a prognostic biomarker in LIHC. Furthermore, genetic mutation analysis using cBioPortal reveals a spectrum of alterations in ESR1, including amplification, missense mutation, deep deletion, splice mutation, and truncating mutation, highlighting the genetic complexity of ESR1 in LIHC. These findings collectively contribute to a deeper understanding of ESR1 dysregulation in LIHC and its clinical implications as a potential therapeutic target and prognostic marker.

Changes of Estrogen in Serum and Estrogen Receptor β in the Relevant Brain Regions Following Mating Behavior of the Male Mandarin Vole Microtus mandarinus

In order to investigate the estrogen and estrogen receptor β changes after mating behavior of male mandarin vole （Microtus mandarinus）, the radioimmunoassay （RIA） and immunohistochemistry methods were used to investigate changes of the serum estrogen （E） concentrations, estrogen immunoreactive neurons （E-IRs） and estrogen receptor β immunoreactive neurons （ERβ-IRs） in the relevant brain regions following mating behavior. Fifteen sexually matured male voles were randomly divided into three groups and treated differently： （1） control group： voles were exposed to clean hard-wood shavings （n=5）, （2） exposure group： voles were exposed to the soiled bedding for more than 24h on which estrous females had been placed （n=5）, and （3） mating group： voles were placed with an estrous female for more than 24h （n=5）. The results showed circulating serum E concentrations were significantly higher in the mating group than in the exposure group and the control group, and there were no significant difference between the exposure group and the control group. E-IRs and ERβ-IRs were detected in the following brain regions related to mating behavior： the arcuate nucleus （ARC）, bed nucleus of the stria terminalis （BST）, lateral septal nucleus （LS）, medial amygdaloid nucleus （ME）, medial preoptic area （MPO） and ventromedial hypothalamic nucleus （VMH）. The results showed that there were significantly more E-IRs in the six brain regions in the mating group than in the control group and the exposure group, and there were no significant difference between the exposure group and the control group except for LS. There was no significant difference in ERβ-IRs in the six brain regions among the three groups, and there were some lighter -stained ERβ-IRs in these brain regions. The results suggested that estrogen affect mating activity of male mandarin voles, but ERβ might not play an important role in mating behavior of male mandarin voles. Instead, it might be through other receptors.

Estrogen,male dominance and esophageal adenocarcinoma:Is there a link?

Esophageal adenocarcinoma is a cancer with poor prognosis, and its incidence has risen sharply over recent decades. Obesity is a major risk factor for developing this cancer and there is a clear male gender bias in the incidence that cannot be fully explained by known risk factors. It is possible that a difference in the expression of estrogen, or its signaling axes, may contribute to this gender bias. We undertook a com- prehensive literature search and analyzed the available data regarding estrogen and estrogen receptor expres- sion, and the possible sex-specific links with esopha- geal adenocarcinoma development. Potentially relevant associations between visceral vs subcutaneous fat deposition and estrogen expression, and the effect of crosstalk between estrogen and leptin signaling were identified. We also found limited studies suggesting a role for estrogen receptor 13 expression in esophageal adenocarcinoma development. The current literature supports speculation on an etiological role for estrogen in the male gender bias in esophageal adenocarcino- ma, but further studies are required.