The prognostic values of estrogen receptor alpha and beta in patients with gastroesophageal cancer: A meta-analysis

Significance of dysregulated M2 macrophage and ESR2 in the ovarian metastasis of gastric cancer

Background

Prognosis of gastric cancer (GC) patients with ovarian metastasis (OM) remains poor. We hereby characterized the role of tumor immune microenvironment (TIME) and identified potential key regulators in the OM with the aim of understanding its molecular basis to develop novel therapeutic targets.

Methods

Transcriptomic analyses of paired primary and ovarian metastatic lesions of seven GC patients from Fudan University Shanghai Cancer Center uncovered and functionally annotated their differentially expressed genes (DEGs). CIBERSORT analysis revealed differential TIME between primary GCs and OMs, which was further validated by multiplex immunofluorescence (mIF). Unique overexpression of candidate regulator in OMs was validated by an immunohistochemical (IHC) staining-based cohort study and in vitro cell growth, migration and invasion assays were conducted to characterize its function in GC progression.

Results

Functional enrichment analyses of DEGs between GCs and matched OMs revealed multiple significantly dysregulated immune-related and cancer-related pathways. Distinctive subsets of immune cells, especially M2 macrophage, were selectively enriched in metastatic lesions. mIF-based quantification further validated the overexpression of CD68+CD206+ M2 macrophage in the OMs. Estrogen receptor 2 (ESR2), which encodes estrogen receptor β (ERβ), was not only potentially correlated with M2 macrophage but also overexpressed in the OM of GC. ESR2 was up-regulated in cancerous tissue and its high expression correlated with younger age, more advanced lymph node metastasis and pathological stage, as well as a worse patient survival. IHC staining of ERβ in the cohort of paired primary and metastatic GCs validated its selective overexpression in OMs. Small-interfering RNAs (siRNAs)-induced knockdown of ESR2 significantly inhibited the invasion and migration of both AGS and HGC-27 GC cell lines.

Conclusions

Comparative RNA-sequencing analysis revealed the dysregulated TIME, M2 macrophage in particular, between primary GC and OM. ESR2 potentially correlated with M2 macrophage and played pro-oncogenic roles in GC progression and metastasis.

Association between menopausal hormone therapy and the risk of gastric cancer: A Korean nationwide population-based cohort study

OBJECTIVE

Gastric cancer (GC) is more common in men than women, but also more common among postmenopausal than premenopausal women. The protective effect of reproductive hormones against GC remains unclear. Therefore, we evaluated the association between menopausal hormone therapy (MHT) and the risk of GC in women.

METHODS

We investigated the national cohort data of women aged over 40 years who underwent health checkups by the Korean National Health Insurance Service in 2009. After excluding individuals with missing data and those previously diagnosed with cancer, 1,354,621 postmenopausal women were included and divided into groups according to their MHT history. We followed the study population until 2018 and analyzed the hazard ratios (HR) with 95 % confidence intervals (CIs) for the incidence rate of GC in a multivariate adjusted model.

RESULTS

The number of women with and without a history of MHT was 214,723 (15.9 %) and 1,139,898 (84.1 %), respectively. During the mean 8.32 ± 0.8 years of follow-up, a total of 12,496 GC cases developed in the study population (10,962 MHT non-users; 1534 MHT users). In the adjusted model, MHT was associated with a 12 % decrease in the development of GC relative to non-use of MHT (HR 0.88; 95 % CI 0.83-0.93). Exposure to MHT for >2 years was linked to a reduction in GC risk, particularly when initiated before the age of 50, giving a 45 % risk reduction.

CONCLUSIONS

According to our large-scale prospective national cohort study, exogenous MHT is associated with a decreased risk of GC in postmenopausal women.

Late age at first birth is a protective factor for oesophageal cancer and gastro-oesophageal reflux: the evidence from the genetic study

Objective

The primary objective of this research endeavor was to examine the underlying genetic causality between the age at first birth (AFB) and four prevalent esophageal diseases, namely oesophageal obstruction (OO), oesophageal varices (OV), gastro-oesophageal reflux (GOR), and oesophageal cancer (OC).

Methods

We conducted a two-sample Mendelian randomization (MR) analysis to examine the causal association between AFB and four prevalent esophageal disorders. We employed eight distinct MR analysis techniques to evaluate causal relationships, encompassing random-effects inverse variance weighted (IVW), MR Egger, weighted median, simple mode, weighted mode, maximum likelihood, penalized weighted median, and fixed-effects IVW. The random-effects IVW method served as the primary approach for our analysis. Furthermore, we executed several sensitivity analyses to assess the robustness of the genetic causal inferences.

Results

The random-effects IVW analysis revealed a significant negative genetic causal association between AFB and both GOR (P < 0.001, Odds Ratio [OR] 95% Confidence Interval [CI] = 0.882 [0.828-0.940]) and OC (P < 0.001, OR 95% CI = 0.998 [0.998-0.999]). Conversely, there was insufficient evidence support to substantiate a genetic causal link between AFB and OO (P = 0.399, OR 95% CI = 0.873 [0.637-1.197]) or OV (P = 0.881, OR 95% CI = 0.978 [0.727-1.314]). The results of sensitivity analyses underscore the robustness and reliability of our MR analysis.

Conclusion

The findings of this investigation substantiate the notion that elevated AFB confers a protective effect against GOR and OC. In addition, no causative association was discerned between AFB and OO or OV at the genetic level.

Different Expression Pattern of G Protein-Coupled Estrogen Receptor GPER1 in Esophageal Squamous Cell Carcinoma and Adenocarcinoma

Esophageal carcinoma is a male-dominant malignancy worldwide, and esophageal adenocarcinoma (EAC) shows more significant sex bias than esophageal squamous cell carcinoma (ESCC) in morbidity and mortality. The G protein-coupled estrogen receptor 1 (GPER1) is involved in several sex-related cancers; however, its expression level in esophageal carcinoma has been poorly investigated and its role is not precisely defined, depending on histological types. In the present study, the mRNA levels of GPER1 in esophageal carcinoma were collected from GEPIA and Oncomine databases for meta-analyses. The protein expression levels of GPER1 were detected by immunohistochemistry in the tissue microarray of EAC and ESCC. The GPER1 selective agonist G1, antagonist G15, and siRNA were applied in vitro to investigate their impacts on esophageal cell lines. Analysis of the RNA levels from the databases showed a decreased expression of GPER1 in overall esophageal carcinoma, and low expression levels of GPER1 were found to be associated with low survival of tumor patients. However, in the subgroup of EAC and its precancerous lesion, Barrett's esophagus, overexpression of GPER1 RNA was increased when compared with the normal tissues. The average staining scores of GPER1 protein in the tissue microarray of EAC were significantly higher than normal esophageal samples, and the rate of positive staining increased with the grade of poor tumor differentiation. The scores of GPER1 protein in ESCC tissues were lower than those in the normal tissues. The results from cell line experiments in vitro showed that the GPER1 agonist G1 inhibited proliferation and promoted apoptosis of ESCC cells EC109 with positive expression of GPER1. G1 had no obvious effect on normal esophageal NE2 cells with weak expression of GPER1. In addition, GPER1 RNA knockdown and application of antagonist G15 reversed the effects of G1 on EC109. The results of this study indicate that the expression levels of GPER1 are higher in EAC than in ESCC, which might be correlated with the dimorphic estrogen signaling pathway in different types of esophageal carcinoma.

Missing link between tissue specific expressing pattern of ERβ and the clinical manifestations in LGBLEL

Purpose

Lacrimal gland benign lymphoepithelial lesion (LGBLEL) is an IgG4-related disease of unknown etiology with a risk for malignant transformation. Estrogen is considered to be related to LGBLEL onset.

Methods

Seventy-eight LGBLEL and 13 control clinical samples were collected and studied to determine the relationship between estrogen and its receptors and LGBLEL development.

Results

The serological analysis revealed no significant differences in the levels of three estrogens be-tween the LGBLEL and control groups. However, immunohistochemical analyses indicated that the expression levels of ERβ and its downstream receptor RERG were relatively lower in LGBLEL samples than in control samples, with higher expression in the lacrimal gland and lower expression in the lymphocyte infiltration region. However, low expression of ERα was detected. The transcriptome sequence analysis revealed upregulated genes associated with LGBLEL enriched in lymphocyte proliferation and activation function; downregulated genes were enriched in epithelial and vascular proliferation functions. The key genes and gene networks were further analyzed. Interactions between B cells and epithelial cells were analyzed due to the identified involvement of leukocyte subsets and epithelial cells. B cell proliferation was found to potentially contribute to lacrimal gland apoptosis.

Conclusion

Therefore, the tissue-heterogeneous expression pattern of ERβ is potentially related to the clinical manifestations and progression of LGBLEL, although further investigations are required to confirm this finding.

GASTRIC CANCER WITH POSITIVE EXPRESSION OF ESTROGEN RECEPTOR ALPHA: A CASE SERIES FROM A SINGLE WESTERN CENTER

AIM

Despite advances in therapies, the prognosis of patients with advanced gastric cancer (GC) remains poor. Several studies have demonstrated the expression of estrogen receptor alpha (ERa); however, its significance in GC remains controversial. The present study aims to report a case series of GC with ERa-positive expression and describe their clinicopathological characteristics and prognosis.

METHODS

We retrospectively evaluated patients with GC who underwent gastrectomy with curative intent between 2009 and 2019. ERa expression was assessed by immunohistochemistry through tissue microarray construction. Patients with ERa-negative gastric adenocarcinoma served as a comparison group.

RESULTS

During the selected period, 6 (1.8%) ERa-positive GC were identified among the 345 GC patients analyzed. All ERa-positive patients were men, aged 34-78 years, and had Lauren diffuse GC and pN+ status. Compared with ERa-negative patients, ERa-positive patients had larger tumor size (p=0.031), total gastrectomy (p=0.012), diffuse/mixed Lauren type (p=0.012), presence of perineural invasion (p=0.030), and lymph node metastasis (p=0.215). The final stage was IIA in one case, IIIA in three cases, and IIIB in two cases. Among the six ERa-positive patients, three had disease recurrence (peritoneal) and died. There was no significant difference in survival between ERa-positive and ERa-negative groups.

CONCLUSIONS

ERa expression is less common in GC, is associated with diffuse histology and presence of lymph node metastasis, and may be a marker related to tumor progression and worse prognosis. Also, a high rate of peritoneal recurrence was observed in ERa-positive patients.

Role of estrogen receptors in health and disease

Estrogen receptors (ERs) regulate multiple complex physiological processes in humans. Abnormal ER signaling may result in various disorders, including reproductive system-related disorders (endometriosis, and breast, ovarian, and prostate cancer), bone-related abnormalities, lung cancer, cardiovascular disease, gastrointestinal disease, urogenital tract disease, neurodegenerative disorders, and cutaneous melanoma. ER alpha (ERα), ER beta (ERβ), and novel G-protein-coupled estrogen receptor 1 (GPER1) have been identified as the most prominent ERs. This review provides an overview of ERα, ERβ, and GPER1, as well as their functions in health and disease. Furthermore, the potential clinical applications and challenges are discussed.

Sex-dependent development of Kras-induced anal squamous cell carcinoma in mice

Anal squamous cell carcinoma (SCC) will be diagnosed in an estimated 9,080 adults in the United States this year, and rates have been rising over the last several decades. Most people that develop anal SCC have associated human papillomavirus (HPV) infection (~85-95%), with approximately 5-15% of anal SCC cases occurring in HPV-negative patients from unknown etiology. This study identified and characterized the Kras-driven, female sex hormone-dependent development of anal squamous cell carcinoma (SCC) in the LSL-KrasG12D; Pdx1-Cre (KC) mouse model that is not dependent on papillomavirus infection. One hundred percent of female KC mice develop anal SCC, while no male KC mice develop tumors. Both male and female KC anal tissue express Pdx1 and Cre-recombinase mRNA, and the activated mutant KrasG12D gene. Although the driver gene mutation KrasG12D is present in anus of both sexes, only female KC mice develop Kras-mutant induced anal SCC. To understand the sex-dependent differences, KC male mice were castrated and KC female mice were ovariectomized. Castrated KC males displayed an unchanged phenotype with no anal tumor formation. In contrast, ovariectomized KC females demonstrated a marked reduction in anal SCC development, with only 15% developing anal SCC. Finally, exogenous administration of estrogen rescued the tumor development in ovariectomized KC female mice and induced tumor development in castrated KC males. These results confirm that the anal SCC is estrogen mediated. The delineation of the role of female sex hormones in mediating mutant Kras to drive anal SCC pathogenesis highlights a subtype of anal SCC that is independent of papillomavirus infection. These findings may have clinical applicability for the papillomavirus-negative subset of anal SCC patients that typically respond poorly to standard of care chemoradiation.

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

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

Interaction of Estradiol and Endoplasmic Reticulum Stress in the Development of Esophageal Carcinoma

Gender differences in esophageal cancer patients indicate that estradiol may have antitumor effects on esophageal cancer. The initiation of endoplasmic reticulum stress (ERS) can induce apoptosis in esophageal cancer cells. However, it is still unknown whether estradiol inhibits the development of esophageal cancer by activating ERS pathway. In this study, the gender difference in the development of esophageal cancer was observed by analyzing clinical data and the experimental tumor xenografts in mice. Meanwhile, we investigated the mechanism of ERS in estradiol-mediated inhibition of esophageal cancer using esophageal squamous cell carcinoma cell line EC109. The proportion of male patients with esophageal cancer was significantly higher than female patients. Meanwhile, male patients were prone to have adventitial invasion. The weight of transplanted tumors in female mice was significantly smaller than that in male mice. In vitro experiments showed estradiol inhibits the viability and migration of EC109 cells by increasing the expression of ERS-related proteins, whereas ERS inhibitor 4-PBA abolished the effects of estradiol. In conclusion, our data demonstrate that sex difference exists in the occurrence of esophageal cancer. Estradiol can inhibit the viability and migration of esophageal cancer cells through the activation of ERS, providing a novel insight for esophageal cancer development, treatment, and prevention.