Bidirectional signaling between the estrogen receptor and the epidermal growth factor receptor

Molecular Changes in Breast Cancer Induced by Radiation Therapy

PURPOSE

Breast cancer treatments are based on prognostic clinicopathologic features that form the basis for therapeutic guidelines. Although the utilization of these guidelines has decreased breast cancer-associated mortality rates over the past three decades, they are not adequate for individualized therapy. Radiation therapy (RT) is the backbone of breast cancer treatment. Although a highly successful therapeutic modality clinically, from a biological perspective, preclinical studies have shown RT to have the potential to alter tumor cell phenotype, immunogenicity, and the surrounding microenvironment, potentially changing the behavior of cancer cells and resulting in a significant variation in RT response. This review presents the recent advances in revealing the complex molecular changes induced by RT in the treatment of breast cancer and highlights the complexities of translating this information into clinically relevant tools for improved prognostic insights and the revelation of novel approaches for optimizing RT.

METHODS AND MATERIALS

Current literature was reviewed with a focus on recent advances made in the elucidation of tumor-associated radiation-induced molecular changes across molecular, genetic, and proteomic bases. This review was structured with the aim of providing an up-to-date overview over the very broad and complex subject matter of radiation-induced molecular changes and radioresistance, familiarizing the reader with the broader issue at hand.

RESULTS

The subject of radiation-induced molecular changes in breast cancer has been broached from various physiological focal points including that of the immune system, immunogenicity and the abscopal effect, tumor hypoxia, breast cancer classification and subtyping, molecular heterogeneity, and molecular plasticity. It is becoming increasingly apparent that breast cancer clinical subtyping alone does not adequately account for variation in RT response or radioresistance. Multiple components of the tumor microenvironment and immune system, delivered RT dose and fractionation schedules, radiation-induced bystander effects, and intrinsic tumor physiology and heterogeneity all contribute to the resultant RT outcome.

CONCLUSIONS

Despite recent advances and improvements in anticancer therapies, tumor resistance remains a significant challenge. As new analytical techniques and technologies continue to provide crucial insight into the complex molecular mechanisms of breast cancer and its treatment responses, it is becoming more evident that personalized anticancer treatment regimens may be vital in overcoming radioresistance.

Double Imprinted Nanoparticles for Sequential Membrane-to-Nuclear Drug Delivery

Efficient and site-specific delivery of therapeutics drugs remains a critical challenge in cancer treatment. Traditional drug nanocarriers such as antibody-drug conjugates are not generally accessible due to their high cost and can lead to serious side effects including life-threatening allergic reactions. Here, these problems are overcome via the engineering of supramolecular agents that are manufactured with an innovative double imprinting approach. The developed molecularly imprinted nanoparticles (nanoMIPs) are targeted toward a linear epitope of estrogen receptor alfa (ERα) and loaded with the chemotherapeutic drug doxorubicin. These nanoMIPs are cost-effective and rival the affinity of commercial antibodies for ERα. Upon specific binding of the materials to ERα, which is overexpressed in most breast cancers (BCs), nuclear drug delivery is achieved via receptor-mediated endocytosis. Consequentially, significantly enhanced cytotoxicity is elicited in BC cell lines overexpressing ERα, paving the way for precision treatment of BC. Proof-of-concept for the clinical use of the nanoMIPs is provided by evaluating their drug efficacy in sophisticated three-dimensional (3D) cancer models, which capture the complexity of the tumor microenvironment in vivo without requiring animal models. Thus, these findings highlight the potential of nanoMIPs as a promising class of novel drug compounds for use in cancer treatment.

Long Non-Coding RNAs, Nuclear Receptors and Their Cross-Talks in Cancer-Implications and Perspectives

Long non-coding RNAs (lncRNAs) play key roles in various epigenetic and post-transcriptional events in the cell, thereby significantly influencing cellular processes including gene expression, development and diseases such as cancer. Nuclear receptors (NRs) are a family of ligand-regulated transcription factors that typically regulate transcription of genes involved in a broad spectrum of cellular processes, immune responses and in many diseases including cancer. Owing to their many overlapping roles as modulators of gene expression, the paths traversed by lncRNA and NR-mediated signaling often cross each other; these lncRNA-NR cross-talks are being increasingly recognized as important players in many cellular processes and diseases such as cancer. Here, we review the individual roles of lncRNAs and NRs, especially growth factor modulated receptors such as androgen receptors (ARs), in various types of cancers and how the cross-talks between lncRNAs and NRs are involved in cancer progression and metastasis. We discuss the challenges involved in characterizing lncRNA-NR associations and how to overcome them. Furthering our understanding of the mechanisms of lncRNA-NR associations is crucial to realizing their potential as prognostic features, diagnostic biomarkers and therapeutic targets in cancer biology.

DNA Damage Responses in Tumors Are Not Proliferative Stimuli, but Rather They Are DNA Repair Actions Requiring Supportive Medical Care

BACKGROUND

In tumors, somatic mutagenesis presumably drives the DNA damage response (DDR) via altered regulatory pathways, increasing genomic instability and proliferative activity. These considerations led to the standard therapeutic strategy against cancer: the disruption of mutation-activated DNA repair pathways of tumors.

PURPOSE

Justifying that cancer cells are not enemies to be killed, but rather that they are ill human cells which have the remnants of physiologic regulatory pathways.

RESULTS

1. Genomic instability and cancer development may be originated from a flaw in estrogen signaling rather than excessive estrogen signaling; 2. Healthy cells with genomic instability exhibit somatic mutations, helping DNA restitution; 3. Somatic mutations in tumor cells aim for the restoration of DNA damage, rather than further genomic derangement; 4. In tumors, estrogen signaling drives the pathways of DNA stabilization, leading to apoptotic death; 5. In peritumoral cellular infiltration, the genomic damage of the tumor induces inflammatory cytokine secretion and increased estrogen synthesis. In the inflammatory cells, an increased growth factor receptor (GFR) signaling confers the unliganded activation of estrogen receptors (ERs); 6. In breast cancer cells responsive to genotoxic therapy, constitutive mutations help the upregulation of estrogen signaling and consequential apoptosis. In breast tumors non-responsive to genotoxic therapy, the possibilities for ER activation via either liganded or unliganded pathways are exhausted, leading to farther genomic instability and unrestrained proliferation.

CONCLUSIONS

Understanding the real character and behavior of human tumors at the molecular level suggests that we should learn the genome repairing methods of tumors and follow them by supportive therapy, rather than provoking additional genomic damages.

The Association Between Epidermal Growth Factor rs3756261 A/G Gene Polymorphism and the Risk of Ankylosing Spondylitis in a Chinese Han Population

Background

Epidermal growth factor (EGF) is a potent pro-angiogenic molecule promoting the angiogenic phenotype of ankylosing spondylitis (AS). Studies demonstrated that EGF rs3756261 polymorphism was associated with the risk of inflammatory diseases, but not including AS.

Methods

To investigate the association between EGF rs3756261 polymorphism and the risk of AS, we genotyped the EGF rs3756261 polymorphism in 208 patients with AS and 412 controls in a Chinese Han population using a custom-by-design 48-Plex SNP scanTM Kit. The serum EGF levels were measured using an enzyme-linked immunosorbent assay in 208 AS patients and 412 controls.

Results

Our data indicated that EGF rs3756261 polymorphism was associated with an increased risk of AS in the Chinese Han population. Stratified analyses indicated that the EGF rs3756261 polymorphism elevated the risk of AS among the males, smokers, drinkers and those aged <30 years. In addition, the EGF rs3756261 polymorphism was related to increased CRP and HLA-B27 levels in AS patients. Next, we found that the average serum levels of EGF were significantly higher in AS patients compared with controls. Meanwhile, EGF serum levels were significantly higher in AG genotype carriers when compared with AA genotype carriers in AS patients.

Conclusion

In conclusion, this study indicated that EGF rs3756261 polymorphism was associated with the risk of AS and EGF serum levels in a Chinese Han population.

Perinatal triphenyl phosphate exposure induces metabolic dysfunctions through the EGFR/ERK/AKT signaling pathway: Mechanistic in vitro and in vivo studies

Triphenyl phosphate (TPhP), a widely used organophosphate-flame retardant, is ubiquitously found in household environments and may adversely affect human health. Evidence indicates that TPhP exposure causes metabolic dysfunctions in vivo; however, the underlying mechanism of such adverse effects has not been comprehensively investigated. Herein, we utilized two in vitro models including mouse and human preadipocytes to delineate adipogenic mechanisms of TPhP. The results revealed that both mouse and human preadipocytes exposed to TPhP concentration-dependently accumulated more fat through a significant upregulation of epidermal growth factor receptor (EGFR). We demonstrated that TPhP significantly promoted adipogenesis through the activation of EGFR/ERK/AKT signaling pathway as evident by a drastic reduction in adipogenesis of preadipocytes cotreated with inhibitors of EGFR and its major effectors. Furthermore, we confirmed the mechanism of TPhP-induced metabolic dysfunctions in vivo. We observed that male mice perinatally exposed to TPhP had a significant increase in adiposity, hepatic triglycerides, insulin resistance, plasma insulin levels, hypotension, and phosphorylated EGFR in gonadal fat. Interestingly, an administration of a potent and selective EGFR inhibitor significantly ameliorated the adverse metabolic effects caused by TPhP. Our findings uncovered a potential mechanism of TPhP-induced metabolic dysfunctions and provided implications on toxic metabolic effects posed by environmental chemicals.

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

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

New Perspectives on Sex Steroid Hormones Signaling in Cancer-Associated Fibroblasts of Non-Small Cell Lung Cancer

The importance of sex hormones, especially estrogen, in the pathogenesis of non-small-cell lung cancer (NSCLC) has attracted attention due to its high incidence among young adults and nonsmokers, especially those who are female. Cancer-associated fibroblasts (CAFs) reside in the cancer stroma and influence cancer growth, invasion, metastasis, and acquisition of drug resistance through interactions with cancer cells and other microenvironmental components. Hormone-mediated cell-cell interactions are classic cell-cell interactions and well-known phenomena in breast cancer and prostate cancer CAFs. In cancers of other organs, including NSCLC, the effects of CAFs on hormone-receptor expression and hormone production in cancer tissues have been reported; however, there are few such studies. Many more studies have been performed on breast and prostate cancers. Recent advances in technology, particularly single-cell analysis techniques, have led to significant advances in the classification and function of CAFs. However, the importance of sex hormones in cell-cell interactions of CAFs in NSCLC remains unclear. This review summarizes reports on CAFs in NSCLC and sex hormones in cancer and immune cells surrounding CAFs. Furthermore, we discuss the prospects of sex-hormone research involving CAFs in NSCLC.

Sexual dimorphism in reactive oxygen species production and a role for integrin α1β1 in estrogen receptor α and β expression in articular cartilage

BACKGROUND

Osteoarthritis (OA) is a debilitating disease involving cartilage degradation. A need remains for the discovery of new molecular targets in cartilage for pharmaceutical intervention of OA. One potential target is integrin α1β1 that protects against OA when it is upregulated by chondrocytes early in the disease process. Integrin α1β1 offers this protection by dampening epidermal growth factor receptor (EGFR) signaling, and its effects are more robust in females compared to males. The aim of this study, therefore, was to measure the impact of itga1 on chondrocyte EGFR activity and downstream reactive oxygen species (ROS) production in male and female mice. Furthermore, chondrocyte expression of estrogen receptor (ER) α and ERβ was measured to investigate the mechanism for sexual dimorphism in the EGFR/integrin α1β1 signaling axis. We hypothesized that integrin α1β1 would decrease ROS production and pEGFR and 3-nitrotyrosine expression, with this effect being greater in females. We further hypothesized that chondrocyte expression of ERα and ERβ would be greater in females compared to males, with a greater effect seen in itga1-null compared to wild-type mice.

MATERIALS AND METHODS

Femoral and tibial cartilage of male and female, wild-type and itga1-null mice were processed for ex vivo confocal imaging of ROS, immunohistochemical analysis of 3-nitrotyrosine, or immunofluorescence of pEGFR and ERα and ERβ.

RESULTS

We show that ROS-producing chondrocytes are more abundant in female itga1-null compared to wild-type mice ex vivo; however, itga1 had limited influence on the percent of chondrocytes stained positively for 3-nitrotyrosine or pEGFR in situ. In addition, we found that itga1 influenced ERα and ERβ expression in femoral cartilage from female mice, and that ERα and ERβ were coexpressed as well as colocalized in chondrocytes. Finally, we show sexual dimorphism in ROS and 3-nitrotyrosine production, but surprisingly not in pEGFR expression.

CONCLUSIONS

Together these data highlight sexual dimorphism in the EGFR/integrin α1β1 signaling axis and underline the need for further investigation into the role of ERs in this biological paradigm. Understanding the molecular mechanisms underlying the development of OA is essential for the development of individualized, sex-specific treatments in this age of personalized medicine.

Influence of location-dependent sex difference on PD-L1, MMR/MSI, and EGFR in colorectal carcinogenesis

BACKGROUND

The incidence and mortality rates of colorectal cancer (CRC) has been reported to be strongly associated to sex/gender difference. CRC shows sexual dimorphism, and sex hormones have been shown to affect the tumor immune microenvironment. This study aimed to investigate location-dependent sex differences in tumorigenic molecular characteristics in patients with colorectal tumors, including adenoma and CRC.

METHODS

A total of 231 participants, including 138 patients with CRC, 55 patients with colorectal adenoma, and 38 healthy controls, were recruited between 2015 and 2021 at Seoul National University Bundang Hospital. All patients underwent colonoscopy and acquired tumor lesion samples were further analyzed for programmed death-ligand 1 (PD-L1), epidermal growth factor receptor (EGFR) expression, deficient mismatch repair (dMMR), and microsatellite instability (MSI) status. This study was registered with ClinicalTrial.gov, number NCT05638542.

RESULTS

The average of combined positive score (CPS) was higher in serrated lesions and polyps (lesions/polyps) compared to conventional adenomas (5.73 and 1.41, respectively, P < 0.001). No significant correlation was found between sex and PD-L1 expression within the groups, regardless of histopathological diagnosis. In multivariate analysis where each sex was further stratified by tumor location due to their interaction in CRC, PD-L1 expression was inversely correlated with males having proximal CRC with a CPS cutoff of 1 (Odds ratio (OR) 0.28, P = 0.034). Females with proximal CRC showed a significant association with dMMR/MSI-high (OR 14.93, P = 0.032) and high EGFR expression (OR 4.17, P = 0.017).

CONCLUSION

Sex and tumor location influenced molecular features such as PD-L1, MMR/MSI status and EGFR expression in CRC, suggesting a possible underlying mechanism of sex-specific colorectal carcinogenesis.

Rosetta Stone for Cancer Cure: Comparison of the Anticancer Capacity of Endogenous Estrogens, Synthetic Estrogens and Antiestrogens

This work presents the history of the recognition of principal regulatory capacities of estrogen hormones having been mistakenly regarded as breast cancer promoting agents for more than 120 years. Comprehensive analysis of the results of clinical, epidemiological, immunological and molecular studies justified that endogenous estrogens are the principal regulators of embryonic development, survival and reproduction via orchestrating appropriate expression and even edition of all genes in mammalians. Medical use of chemically modified synthetic estrogens caused toxic complications; thromboembolic events and increased cancer risk in female organs as they proved to be endocrine disruptors deregulating estrogen receptors (ERs) rather than their activators. Synthetic estrogen treatment exhibits ambiguous correlations with cancer risk at different sites, which may be attributed to an inhibition of the unliganded activation of estrogen receptors (ERs) coupled with compensatory liganded activation. The principle of estrogen induced breast cancer led to the introduction of antiestrogen therapies against this tumor; inhibition of the liganded activation of estrogen receptors and aromatase enzyme activity. The initial enthusiasm turned into disappointment as the majority of breast cancers proved to be primarily resistant to antiestrogens. In addition, nearly all patients showing earlier good tumor responses to endocrine therapy, later experienced secondary resistance leading to metastatic disease and fatal outcome. Studying the molecular events in tumors responsive and unresponsive to antiestrogen therapy, it was illuminated that a complete inhibition of liganded ER activation stimulates the growth of cancers, while a successful compensatory upregulation of estrogen signal may achieve DNA restoration, tumor regression and patient's survival. Recognition of the principal role of endogenous estrogens in gene expression, gene edition and DNA repair, estrogen treatment and stimulation of ER expression in patients may bring about a great turn in medical practice.

BDE-47, -99, -209 and Their Ternary Mixture Disrupt Glucose and Lipid Metabolism of Hepg2 Cells at Dietary Relevant Concentrations: Mechanistic Insight through Integrated Transcriptomics and Proteomics Analysis

Polybrominated diphenyl ethers (PBDEs) are persistent organic chemicals implied as flame retardants. Humans are mainly exposed to BDE-47, -99, and -209 congeners by diet. PBDEs are metabolic disruptors with the liver as the main target organ. To investigate their mode of action at a human-relevant concentration, we exposed HepG2 cells to these congeners and their mixture at 1 nM, analyzing their transcriptomic and proteomic profiles. KEGG pathways and GSEA Hallmarks enrichment analyses evidenced that BDE-47 disrupted the glucose metabolism and hypoxia pathway; all the congeners and the MIX affected lipid metabolism and signaling Hallmarks regulating metabolism as mTORC1 and PI3K/AKT/MTOR. These results were confirmed by glucose secretion depletion and increased lipid accumulation, especially in BDE-47 and -209 treated cells. These congeners also affected the EGFR/MAPK signaling; further, BDE-47 enriched the estrogen pathway. Interestingly, BDE-209 and the MIX increased ERα gene expression, whereas all the congeners and the MIX induced ERβ and PPARα. We also found that PBDEs modulated several lncRNAs and that HNRNAP1 represented a central hub in all the four interaction networks. Overall, the PBDEs investigated affected glucose and lipid metabolism with different underlying modes of action, as highlighted by the integrated omics analysis, at a dietary relevant concentration. These results may support the mechanism-based risk assessment of these compounds in relation to liver metabolism disruption.

In vitro breast cancer models for studying mechanisms of resistance to endocrine therapy

The development of endocrine resistance is a common reason for the failure of endocrine therapies in hormone receptor-positive breast cancer. This review provides an overview of the different types of in vitro models that have been developed as tools for studying endocrine resistance. In vitro models include cell lines that have been rendered endocrine-resistant by ex vivo treatment; cell lines with de novo resistance mechanisms, including genetic alterations; three-dimensional (3D) spheroid, co-culture, and mammosphere techniques; and patient-derived organoid models. In each case, the key discoveries, different analysis strategies that are suitable, and strengths and weaknesses are discussed. Certain recently developed methodologies that can be used to further characterize the biological changes involved in endocrine resistance are then emphasized, along with a commentary on the types of research outcomes that using these techniques can support. Finally, a discussion anticipates how these recent developments will shape future trends in the field. We hope this overview will serve as a useful resource for investigators that are interested in understanding and testing hypotheses related to mechanisms of endocrine therapy resistance.

Lysophospholipid Mediators in Health and Disease

Lysophospholipids, exemplified by lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P), are produced by the metabolism and perturbation of biological membranes. Both molecules are established extracellular lipid mediators that signal via specific G protein-coupled receptors in vertebrates. This widespread signaling axis regulates the development, physiological functions, and pathological processes of all organ systems. Indeed, recent research into LPA and S1P has revealed their important roles in cellular stress signaling, inflammation, resolution, and host defense responses. In this review, we focus on how LPA regulates fibrosis, neuropathic pain, abnormal angiogenesis, endometriosis, and disorders of neuroectodermal development such as hydrocephalus and alopecia. In addition, we discuss how S1P controls collective behavior, apoptotic cell clearance, and immunosurveillance of cancers. Advances in lysophospholipid research have led to new therapeutics in autoimmune diseases, with many more in earlier stages of development for a wide variety of diseases, such as fibrotic disorders, vascular diseases, and cancer.

A possible critical dosing period of p-cumylphenol for development of cystic kidneys in rat neonates

In accordance with a previous report on cystic kidneys induced in rat neonates when dosed with p-cumylphenol (PCP) for 18 days from postnatal day (PND) 4, 3 rat neonates were dosed with PCP once a day for 14 days, either from PND 14, 21, 28, 35, or 42 as W2, W3, W4, W5, and W6 groups, respectively, to investigate whether dosing periods in different PNDs influenced the development of cystic renal tubules. The lesion was striking in the W2 group and at a lesser magnitude in the W3 group, whereas either kidney was unaffected when dosing was initiated beyond PND 28. These findings, together with the results from the previous study, suggested that PND 14-28 is a critical dosing period for PCP to develop cystic kidneys in rat neonates. The lining epithelium of the cystic tubules was immunohistochemically positive for AQP2. This finding and the anatomical location indicated that the cystic tubules were of collecting duct origin. Either obstruction, fluid accumulation, or reparative hyperplasia of the lining epithelium was unlikely to be involved in the formation of cystic tubules lined with a monolayer of cuboidal or columnar epithelium with a high nuclear density. Thus, the follow-up investigation on PCP suggested a critical dosing period of PND 14-28 in rat neonates for the development of cystic dilation of renal collecting ducts. This study further supports that additive hyperplasia of the lining epithelium is a fundamental basis of this unique lesion.

Targeting Estrogens and Various Estrogen-Related Receptors against Non-Small Cell Lung Cancers: A Perspective

Non-small cell lung cancers (NSCLCs) account for ~85% of lung cancer cases worldwide. Mammalian lungs are exposed to both endogenous and exogenous estrogens. The expression of estrogen receptors (ERs) in lung cancer cells has evoked the necessity to evaluate the role of estrogens in the disease progression. Estrogens, specifically 17β-estradiol, promote maturation of several tissue types including lungs. Recent epidemiologic data indicate that women have a higher risk of lung adenocarcinoma, a type of NSCLC, when compared to men, independent of smoking status. Besides ERs, pulmonary tissues both in healthy physiology and in NSCLCs also express G-protein-coupled ERs (GPERs), epidermal growth factor receptor (EGFRs), estrogen-related receptors (ERRs) and orphan nuclear receptors. Premenopausal females between the ages of 15 and 50 years synthesize a large contingent of estrogens and are at a greater risk of developing NSCLCs. Estrogen-ER/GPER/EGFR/ERR-mediated activation of various cell signaling molecules regulates NSCLC cell proliferation, survival and apoptosis. This article sheds light on the most recent achievements in the elucidation of sequential biochemical events in estrogen-activated cell signaling pathways involved in NSCLC severity with insight into the mechanism of regulation by ERs/GPERs/EGFRs/ERRs. It further discusses the success of anti-estrogen therapies against NSCLCs.

Role of sex hormones in lung cancer

Lung cancer represents the world's leading cause of cancer deaths. Sex differences in the incidence and mortality rates for various types of lung cancers have been identified, but the biological and endocrine mechanisms implicated in these disparities have not yet been determined. While some cancers such as lung adenocarcinoma are more commonly found among women than men, others like squamous cell carcinoma display the opposite pattern or show no sex differences. Associations of tobacco product use rates, susceptibility to carcinogens, occupational exposures, and indoor and outdoor air pollution have also been linked to differential rates of lung cancer occurrence and mortality between sexes. While roles for sex hormones in other types of cancers affecting women or men have been identified and described, little is known about the influence of sex hormones in lung cancer. One potential mechanism identified to date is the synergism between estrogen and some tobacco compounds, and oncogene mutations, in inducing the expression of metabolic enzymes, leading to enhanced formation of reactive oxygen species and DNA adducts, and subsequent lung carcinogenesis. In this review, we present the literature available regarding sex differences in cancer rates, associations of male and female sex hormones with lung cancer, the influence of exogenous hormone therapy in women, and potential mechanisms mediated by male and female sex hormone receptors in lung carcinogenesis. The influence of biological sex on lung disease has recently been established, thus new research incorporating this variable will shed light on the mechanisms behind the observed disparities in lung cancer rates, and potentially lead to the development of new therapeutics to treat this devastating disease.

Seasonal expressions of ERα, ERβ, EGF, EGFR, PI3K and Akt in the scent glands of the muskrats (Ondatra zibethicus)

Epidermal growth factor (EGF) is an important autocrine and/or paracrine mediator of steroid hormones to stimulate growth and differentiation in mammals. The aim of this study is to investigate seasonal expressions of estrogen receptor α (ERα), estrogen receptor β (ERβ), EGF, epidermal growth factor receptor (EGFR), phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt) in the scent glands of the muskrats during the breeding and non-breeding seasons. Histologically, three types of cells including the glandular cells, interstitial cells and epithelial cells were identified in the scent glands in both seasons. Immunohistochemical results showed that ERα, ERβ, EGF, EGFR, PI3K and Akt were presented in the different types of cells of the scent glands during the breeding and non-breeding seasons. Transcriptome data of the scent glandular tissues from muskrats in the breeding and non-breeding seasons showed that differential seasonal changes might be related to the estrogen-EGFR signaling pathway. The gene expression levels of ERα, ERβ, EGF, EGFR, PI3K were increased, while the gene expression level of Akt were decreased in the breeding season than those in the non-breeding season. Besides, the concentrations of 17β-estradiol (E₂) in the serum and the scent glandular tissues were remarkably higher in the breeding season than those of the non-breeding season. Taken together, our results suggested that EGFR signaling pathway may coordinate with ERs signaling to regulate the seasonal changes of the scent glandular functions.

The Crossroads between Zinc and Steroidal Implant-Induced Growth of Beef Cattle

Growth-promoting technologies such as steroidal implants have been utilized in the beef industry for over 60 years and remain an indispensable tool for improving economic returns through consistently improved average daily gain via increased skeletal muscle hypertrophy. Zinc has been implicated in skeletal muscle growth through protein synthesis, satellite cell function, and many other growth processes. Therefore, the objective of this review was to present the available literature linking Zn to steroidal implant-induced protein synthesis and other metabolic processes. Herein, steroidal implants and their mode of action, the biological importance of Zn, and several connections between steroidal implants and Zn related to growth processes are discussed. These include the influence of Zn on hormone receptor signaling, circulating insulin-like growth factor-1 concentrations, glucose metabolism, protein synthesis via mTOR, and satellite cell proliferation and differentiation. Supplemental Zn has also been implicated in improved growth rates of cattle utilizing growth-promoting technologies, and steroidal implants appear to alter liver and circulating Zn concentrations. Therefore, this review provides evidence of the role of Zn in steroidal implant-induced growth yet reveals gaps in the current knowledge base related to optimizing Zn supplementation strategies to best capture growth performance improvements offered through steroidal implants.

Cytochrome P450: Implications for human breast cancer

The treatment options for breast cancer include endocrine therapy, targeted therapy and chemotherapy. However, some patients with triple-negative breast cancer cannot benefit from these methods. Therefore, novel therapeutic targets should be developed. The cytochrome P450 enzyme (CYP) is a crucial metabolic oxidase, which is involved in the metabolism of endogenous and exogenous substances in the human body. Some products undergoing the metabolic pathway of the CYP enzyme, such as hydroxylated polychlorinated biphenyls and 4-chlorobiphenyl, are toxic to humans and are considered to be potential carcinogens. As a class of multi-gene superfamily enzymes, the subtypes of CYPs are selectively expressed in breast cancer tissues, especially in the basal-like type. In addition, CYPs are essential for the activation or inactivation of anticancer drugs. The association between CYP expression and cancer risk, tumorigenesis, progression, metastasis and prognosis has been widely reported in basic and clinical studies. The present review describes the current findings regarding the importance of exploring metabolic pathways of CYPs and gene polymorphisms for the development of vital therapeutic targets for breast cancer.

CRISPR/Cas9 uPAR Gene Knockout Results in Tumor Growth Inhibition, EGFR Downregulation and Induction of Stemness Markers in Melanoma and Colon Carcinoma Cell Lines

uPAR is a globular protein, tethered to the cell membrane by a GPI-anchor involved in several cancer-related properties and its overexpression commonly correlates with poor prognosis and metastasis. We investigated the consequences of uPAR irreversible loss in human melanoma and colon cancer cell lines, knocking out its expression by CRISPR/Cas9. We analyzed through flow cytometry, western blotting and qPCR, the modulation of the most known cancer stem cells-associated genes and the EGFR while we observed the proliferation rate exploiting 2D and 3D cellular models. We also generated uPAR “rescue” expression cell lines as well as we promoted the expression of only its 3’UTR to demonstrate the involvement of uPAR mRNA in tumor progression. Knocking out PLAUR, uPAR-encoding gene, we observed an inhibited growth ratio unexpectedly coupled with a significant percentage of cells acquiring a stem-like phenotype. In vivo experiments demonstrated that uPAR loss completely abrogates tumorigenesis despite the gained stem-like profile. Nonetheless, we proved that the reintroduction of the 3’UTR of PLAUR gene was sufficient to restore the wild-type status validating the hypothesis that such a region may act as a “molecular sponge”. In particular miR146a, by binding PLAUR 3’ UTR region might be responsible for uPAR-dependent inhibition of EGFR expression.

Oestrogen actions contribute to female gender-specific risks in the development of lung carcinoma

Lung cancer is increasing in incidence particularly among women, associated with a global change in smoking habits. Steroid hormones, particularly oestrogen exert an influence on tumour progression in tissues where their target receptor is expressed. Oestrogen receptor, particularly ERβ is highly expressed in the lung and becomes more highly expressed in lung carcinogenesis. Genes involved in the process of lung carcinoma progression and signalling cascades linked to invasion and angiogenesis are modulated by oestrogen receptors. This review intends to collate recently published evidence identifying a role for oestrogen in the initiation and progression of lung carcinoma and how these two processes are differentially affected by circulating oestrogens both in women and in men. Circulating oestrogens may be a significant risk factor in women's susceptibility to lung carcinoma and also provide an additional approach for more targeted therapy.

Signalling mechanisms in the cardiovascular protective effects of estrogen: With a focus on rapid/membrane signalling

In modern society, cardiovascular disease remains the biggest single threat to life, being responsible for approximately one third of worldwide deaths. Male prevalence is significantly higher than that of women until after menopause, when the prevalence of CVD increases in females until it eventually exceeds that of men. Because of the coincidence of CVD prevalence increasing after menopause, the role of estrogen in the cardiovascular system has been intensively researched during the past two decades in vitro, in vivo and in observational studies. Most of these studies suggested that endogenous estrogen confers cardiovascular protective and anti-inflammatory effects. However, clinical studies of the cardioprotective effects of hormone replacement therapies (HRT) not only failed to produce proof of protective effects, but also revealed the potential harm estrogen could cause. The "critical window of hormone therapy" hypothesis affirms that the moment of its administration is essential for positive treatment outcomes, pre-menopause (3-5 years before menopause) and immediately post menopause being thought to be the most appropriate time for intervention. Since many of the cardioprotective effects of estrogen signaling are mediated by effects on the vasculature, this review aims to discuss the effects of estrogen on vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) with a focus on the role of estrogen receptors (ERα, ERβ and GPER) in triggering the more recently discovered rapid, or membrane delimited (non-genomic), signaling cascades that are vital for regulating vascular tone, preventing hypertension and other cardiovascular diseases.

Hormonal Carcinogenesis in Canine Mammary Cancer: Molecular Mechanisms of Estradiol Involved in Malignant Progression

Mammary cancer is a frequent neoplasia in female dogs, in which most important risk factors are hormonal. Sexual hormones as estradiol play an important role in mammary carcinogenesis, being able to induce carcinogenic initiation, promotion and progression. However, the molecular mechanisms involved are incompletely understood. Estradiol is synthesized mainly in the ovaries, nevertheless, high concentrations of estradiol and some of its hormonal precursors have also been described in malignant mammary tumor tissue. The mechanisms of action of estradiol include the classic genomic effects that modulate gene transcription, and non-genomic effects, which trigger quick effects after estradiol binds to its specific receptors. These responses modulate various intracellular signaling pathways, triggering post-translational modification of several proteins. This review will discuss the well-known underlying mechanisms associated with the action of estradiol in the malignant progression of canine mammary tumors.

Expression of Estrogen and Progesterone Receptors in Papillary Thyroid Carcinoma in Korea

Purpose

The aim of this study was to examine the rate of expression of estrogen receptor α (ERα) and β1 (ERβ1), progesterone receptor (PR), and rate of overexpression of epidermal growth factor receptor (EGFR) in a relatively large cohort of patients with papillary thyroid carcinoma (PTC). We also aimed to examine whether each receptor influenced clinicopathological characteristics and prognosis of PTC.

Materials and Methods

We made a microarray of paraffin-embedded PTC surgical tissues from 436 patients. We compared the results of the immunohistochemical staining for each hormone receptor with clinicopathological characteristics.

Results

The positive expression rate of hormonal receptors was 40.4% for ERα, 83.7% for ERβ1, and 71.3% for PR in patients with PTC. Overexpression of EGFR was shown in 19.3% of patients with PTC. The age was lower (44.6±12.1 years vs. 47.1±12.5 years, p=0.040) and tumor smaller (0.96±0.69 cm vs. 1.13±0.82 cm, p=0.020) in the ERα positive group, which also showed higher PR positivity (80.7% vs. 65.0%, p < 0.001) and overexpression of EGFR (27.3% vs. 13.8%, p < 0.001). However, neither the positivity of hormone receptors nor overexpression of EGFR affected the recurrence of PTC.

Conclusion

In conclusion, most (94.6%) patients with PTC were found to exhibit positive expression for ERs or PR. We also found that neither the positive expression of hormone receptors nor overexpression of EGFR were associated with the recurrence of PTC.

Sexual Dimorphism in Colon Cancer

A higher incidence of colorectal cancer (CRC) is found in males compared to females. Young women (18-44 years) with CRC have a better survival outcome compared to men of the same age or compared to older women (over 50 years), indicating a global incidence of sexual dimorphism in CRC rates and survival. This suggests a protective role for the sex steroid hormone estrogen in CRC development. Key proliferative pathways in CRC tumorigenesis exhibit sexual dimorphism, which confer better survival in females through estrogen regulated genes and cell signaling. Estrogen regulates the activity of a class of Kv channels (KCNQ1:KCNE3), which control fundamental ion transport functions of the colon and epithelial mesenchymal transition through bi-directional interactions with the Wnt/β-catenin signalling pathway. Estrogen also modulates CRC proliferative responses in hypoxia via the novel membrane estrogen receptor GPER and HIF1A and VEGF signaling. Here we critically review recent clinical and molecular insights into sexual dimorphism of CRC biology modulated by the tumor microenvironment, estrogen, Wnt/β-catenin signalling, ion channels, and X-linked genes.

Role of nuclear and membrane estrogen signaling pathways in the male and female reproductive tract

Estrogen signaling through the main estrogen receptor, estrogen receptor 1 (ESR1; also known as ERα), is essential for normal female and male reproductive function. Historically, studies of estrogen action have focused on the classical genomic pathway. Although this is clearly the major pathway for steroid hormone actions, these hormones also signal through rapid non-classical effects involving cell membrane actions. Reports of rapid effects of estrogens extend for more than half a century, but recent results have expanded understanding of the identity, structure, function and overall importance of membrane receptors in estrogen responses. Key findings in this field were the immunohistochemical detection of ESR1 in cell membranes and demonstration that a portion of newly synthesized ESR1 is routed to the membrane by palmitoylation. These receptors in the membrane can then signal through protein kinases and other mechanisms following ligand binding to alter cell function. Another crucial advance in the field was development of transgenic mice expressing normal amounts of functional nuclear ESR1 (nESR1) but lacking membrane ESR1 (mESR1). Both male and female transgenic mice lacking mESR1 were infertile as adults, and both sexes had extensive reproductive abnormalities. Transgenic mice lacking mESR1 were highly protected from deleterious effects of neonatal estrogen administration, and estrogen effects on the histone methyltransferase Enhancer of Zeste homolog 2 that are mediated through mESR1 could have significant effects on epigenetic imprinting. In summary, signaling through mESR1 is essential for normal male and female reproductive function and fertility, and is a critical enabler of normal estrogen responses in vivo. Although the precise role of mESR1 in estrogen responses remains to be established, future research in this area should clarify its mechanism of action and lead to a better understanding of how mESR1 signaling works with classical genomic signaling through nESR1 to promote full estrogenic responses.

Microenvironmental Determinants of Breast Cancer Metastasis: Focus on the Crucial Interplay Between Estrogen and Insulin/Insulin-Like Growth Factor Signaling

The development and progression of the great majority of breast cancers (BCs) are mainly dependent on the biological action elicited by estrogens through the classical estrogen receptor (ER), as well as the alternate receptor named G-protein–coupled estrogen receptor (GPER). In addition to estrogens, other hormones and growth factors, including the insulin and insulin-like growth factor system (IIGFs), play a role in BC. IIGFs cooperates with estrogen signaling to generate a multilevel cross-communication that ultimately facilitates the transition toward aggressive and life-threatening BC phenotypes. In this regard, the majority of BC deaths are correlated with the formation of metastatic lesions at distant sites. A thorough scrutiny of the biological and biochemical events orchestrating metastasis formation and dissemination has shown that virtually all cell types within the tumor microenvironment work closely with BC cells to seed cancerous units at distant sites. By establishing an intricate scheme of paracrine interactions that lead to the expression of genes involved in metastasis initiation, progression, and virulence, the cross-talk between BC cells and the surrounding microenvironmental components does dictate tumor fate and patients’ prognosis. Following (i) a description of the main microenvironmental events prompting BC metastases and (ii) a concise overview of estrogen and the IIGFs signaling and their major regulatory functions in BC, here we provide a comprehensive analysis of the most recent findings on the role of these transduction pathways toward metastatic dissemination. In particular, we focused our attention on the main microenvironmental targets of the estrogen-IIGFs interplay, and we recapitulated relevant molecular nodes that orientate shared biological responses fostering the metastatic program. On the basis of available studies, we propose that a functional cross-talk between estrogens and IIGFs, by affecting the BC microenvironment, may contribute to the metastatic process and may be regarded as a novel target for combination therapies aimed at preventing the metastatic evolution.

Mechanisms of Estradiol-induced EGF-like Factor Expression and Oocyte Maturation via G Protein-coupled Estrogen Receptor

Estrogen is an important modulator of reproductive activity through nuclear receptors and G protein-coupled estrogen receptor (GPER). Here, we observed that both estradiol and the GPER-specific agonist G1 rapidly induced cyclic adenosine monophosphate (cAMP) production in cumulus cells, leading to transient stimulation of phosphorylated cAMP response element binding protein (CREB), which was conducive to the transcription of epidermal growth factor (EGF)-like factors, amphiregulin, epiregulin, and betacellulin. Inhibition of GPER by G15 significantly reduced estradiol-induced CREB phosphorylation and EGF-like factor gene expression. Consistently, the silencing of GPER expression in cultured cumulus cells abrogated the estradiol-induced CREB phosphorylation and EGF-like factor transcription. In addition, the increase in EGF-like factor expression in the cumulus cells is associated with EGF receptor (EFGR) tyrosine kinase phosphorylation and extracellular signal-regulated kinase 1/2 (ERK1/2) activation. Furthermore, we demonstrated that GPER-mediated phosphorylation of EGFR and ERK1/2 was involved in reduced gap junction communication, cumulus expansion, increased oocyte mitochondrial activity and first polar body extrusion. Overall, our study identified a novel function for estrogen in regulating EGFR activation via GPER in cumulus cells during oocyte maturation.

Gender-specific aspects of epidemiology, molecular genetics and outcome: lung cancer

Lung cancer remains the leading cause of cancer-related deaths worldwide in women and men. In incidence, lung cancer ranks second, surpassed by breast cancer in women and prostate cancer in men. However, the historical differences in mortality and incidence rate between both sexes have changed in the last years. In the last decades, we have also witnessed an increased number of lung cancer in female never-smokers. These disparities have grown our interest in studying the impact of the gender and sex in the presentation of lung cancer. The aetiology is yet to be fully elucidated, but the data are clear so far: there is a growing divide between lung cancer presentation in women and men that will change our management and study of lung cancer. This article aims to review the sex and gender differences in lung cancer.

Compensatory Estrogen Signal Is Capable of DNA Repair in Antiestrogen-Responsive Cancer Cells via Activating Mutations

Cancer cells are embarrassed human cells exhibiting the remnants of same mechanisms for DNA stabilization like patients have in their healthy cells. Antiestrogens target the liganded activation of ERs, which is the principal means of genomic regulation in both patients and their tumors. The artificial blockade of liganded ER activation is an emergency situation promoting strong compensatory actions even in cancer cells. When tumor cells are capable of an appropriate upregulation of ER signaling resulting in DNA repair, a tumor response may be detected. In contrast, when ER signaling is completely inhibited, tumor cells show unrestrained proliferation, and tumor growth may be observed. The laboratory investigations of genomic mechanisms in antiestrogen-responsive and antiestrogen-unresponsive tumor cells have considerably enhanced our knowledge regarding the principal regulatory capacity of estrogen signaling. In antiestrogen-responsive tumor cells, a compensatory increased expression and liganded activation of estrogen receptors (ERs) result in an apoptotic death. Conversely, in antiestrogen resistant tumors exhibiting a complete blockade of liganded ER activation, a compensatory effort for unliganded ER activation is characteristic, conferred by the increased expression and activity of growth factor receptors. However, even extreme unliganded ER activation is incapable of DNA restoration when the liganded ER activation is completely blocked. Researchers mistakenly suspect even today that in tumors growing under antiestrogen treatment, the increased unliganded activation of estrogen receptor via activating mutations is an aggressive survival technique, whilst it is a compensatory effort against the blockade of liganded ER activation. The capacity of liganded ERs for genome modification in emergency states provides possibilities for estrogen/ER use in medical practice including cancer cure.

Mechanistic Models of Signaling Pathways Reveal the Drug Action Mechanisms behind Gender-Specific Gene Expression for Cancer Treatments

Despite the existence of differences in gene expression across numerous genes between males and females having been known for a long time, these have been mostly ignored in many studies, including drug development and its therapeutic use. In fact, the consequences of such differences over the disease mechanisms or the drug action mechanisms are completely unknown. Here we applied mechanistic mathematical models of signaling activity to reveal the ultimate functional consequences that gender-specific gene expression activities have over cell functionality and fate. Moreover, we also used the mechanistic modeling framework to simulate the drug interventions and unravel how drug action mechanisms are affected by gender-specific differential gene expression. Interestingly, some cancers have many biological processes significantly affected by these gender-specific differences (e.g., bladder or head and neck carcinomas), while others (e.g., glioblastoma or rectum cancer) are almost insensitive to them. We found that many of these gender-specific differences affect cancer-specific pathways or in physiological signaling pathways, also involved in cancer origin and development. Finally, mechanistic models have the potential to be used for finding alternative therapeutic interventions on the pathways targeted by the drug, which lead to similar results compensating the downstream consequences of gender-specific differences in gene expression.

Genome-wide identification of estrogen receptor binding sites reveals novel estrogen-responsive pathways in adult male germ cells

Spermatogenesis occurs in the seminiferous epithelium that shows the presence of estrogen receptors alpha (ERα) and beta (ERβ), both of which regulate gene transcription by binding to the DNA. Estrogen responsive phases of spermatogenesis are well documented; however, the genes regulated remain inexplicit. To study the regulation of genes by estrogen in male germ cells, we performed chromatin immunoprecipitation (ChIP) sequencing for ERα and ERβ under normal physiological conditions. A total of 27 221 DNA binding regions were enriched with ERα and 20 926 binding sites with ERβ. Majority of the peaks were present in the intronic regions and located 20 kb upstream or downstream from the transcription start site (TSS). Pathway analysis of the genes enriched by ChIP-Seq showed involvement in several biological pathways. Genes involved in pathways whose role in spermatogenesis is unexplored were validated; these included prolactin, GnRH, and oxytocin signaling. All the selected genes showed the presence of estrogen response elements (EREs) in their binding region and were also found to be significantly enriched by ChIP-qPCR. Functional validation using seminiferous tubule culture after treatment with estrogen receptor subtype-specific agonist and antagonist confirmed the regulation of these genes by estrogen through its receptors. The genes involved in these pathways were also found to be regulated by the respective receptor subtypes at the testicular level in our in vivo estrogen receptor agonist rat models. Our study provides a genome-wide map of ERα and ERβ binding sites and identifies the genes regulated by them in the male germ cells under normal physiological conditions.

Hormone receptor expression correlates with EGFR gene mutation in lung cancer in patients with simultaneous primary breast cancer

Background

The coexistence of double primaries of lung cancer (LC) and breast cancer (BC) are not uncommon in women, but there has been limited research conducted of their molecular association. To decipher the internal pathogenesis of LC in patients with concurrent BC and LC, this study explored the clinical factors and relationship between hormone receptor (HR) expression and epidermal growth factor receptor (EGFR) gene mutation.

Methods

The clinicopathological characteristics of 400 female patients clinically diagnosed with double primary LC and BC at Fudan University Shanghai Cancer Center were collected. Pathological discrimination was performed to further confirm the double primaries in patients with available tissues. LC samples were then examined to detect EGFR gene mutation status by PCR-based assays and HR expression by immunohistochemistry (IHC). As a control cohort, the characteristics of 114 consecutive patients with LC only were compared with the double-primary patient group.

Results

A total of 169 patients were pathologically confirmed with simultaneous LC and BC between January 2010 and October 2018. The dominant LC subtype was adenocarcinoma (ADC) (95.1%), and invasive ductal carcinoma (IDC) was the main BC subtype (71.0%). Synchronous and metachronous double primary BC-LC cases accounted for 39.1% and 60.9% of the patients, respectively. The absence of family cancer history was associated with a shorter interval between the two primary cancer diagnoses. Among 64 patients with EGFR mutations, 34.4% had HR-positive LC tissue, compared with 0/24 (0%) of those with EGFR wild-type LC (P<0.001). All of the patients with positive HR expression harbored an activating EGFR mutation (n=22); however, no correlation was observed in the control cohort.

Conclusions

Double primary BC-LC patients have distinctive clinicopathological features compared to those with LC only. The expression of HRs is significantly correlated with EGFR mutation status of LC tissues.

CDK7 Inhibition is Effective in all the Subtypes of Breast Cancer: Determinants of Response and Synergy with EGFR Inhibition

CDK7, a transcriptional cyclin-dependent kinase, is emerging as a novel cancer target. Triple-negative breast cancers (TNBC) but not estrogen receptor-positive (ER+) breast cancers have been reported to be uniquely sensitive to the CDK7 inhibitor THZ1 due to the inhibition of a cluster of TNBC-specific genes. However, bioinformatic analysis indicates that CDK7 RNA expression is associated with negative prognosis in all the major subtypes of breast cancer. To further elucidate the effects of CDK7 inhibition in breast cancer, we profiled a panel of cell lines representing different breast cancer subtypes. THZ1 inhibited cell growth in all subtypes (TNBC, HER2+, ER+, and HER2+/ER+) with no apparent subtype selectivity. THZ1 inhibited CDK7 activity and induced G1 arrest and apoptosis in all the tested cell lines, but THZ1 sensitivity did not correlate with CDK7 inhibition or CDK7 expression levels. THZ1 sensitivity across the cell line panel did not correlate with TNBC-specific gene expression but it was found to correlate with the differential inhibition of three genes: CDKN1B, MYC and transcriptional coregulator CITED2. Response to THZ1 also correlated with basal CITED2 protein expression, a potential marker of CDK7 inhibitor sensitivity. Furthermore, all of the THZ1-inhibited genes examined were inducible by EGF but THZ1 prevented this induction. THZ1 had synergistic or additive effects when combined with the EGFR inhibitor erlotinib, with no outward selectivity for a particular subtype of breast cancer. These results suggest a potential broad utility for CDK7 inhibitors in breast cancer therapy and the potential for combining CDK7 and EGFR inhibitors.

The prognostic factors of recurrence and survival in female patients with lung adenocarcinoma and breast cancer

BACKGROUND

The aim of this study was to verify the predictors of recurrence and survival in lung adenocarcinoma patients with experiences of breast cancer therapies.

METHODS

We retrospectively reviewed consecutive patients who were treated at our hospital for lung adenocarcinoma from 2004/01 to 2014/03. The patients were divided into groups of those with lung adenocarcinoma alone and those with lung and breast cancer. Kaplan-Meier plots and log-rank tests were used to estimate outcomes.

RESULTS

54 patients with lung adenocarcinoma and breast cancer were compared with 457 patients with single primary lung adenocarcinomas. After propensity score matching with control of age, operation type, smoking status and pathologic stage, tumor differentiation, recurrence rate and tumor size were significantly different between two groups. The significant predictors for recurrence included undergone chemotherapy (HR = 25, p < 0.001), moderate/poor differentiation (HR = 8.125, p = 0.012), tumor size ≧ 2 cm (HR = 15, p < 0.001), LVSI (HR = 13.67, p = 0.031) and GGO ratio < 50% (HR = 14.667, p = 0.014). The significant prognostic factors for survival were accepted chemotherapy (HR = 6.182, p = 0.021), LVSI (HR = 22, p = 0.012) and GGO ratio < 50% (HR = 9.143, p = 0.045). Kaplan-Meier analysis revealed that patients with lung adenocarcinoma and breast cancer had a better 5-year disease-free survival (p = 0.009), while the Her2-negative patients obtained a better overall survival (p = 0.038).

CONCLUSIONS

In patients with breast cancer and lung adenocarcinoma, independent risk factors of recurrence were undergone chemotherapy, moderate/poor differentiation, tumor size ≧ 2 cm, LVSI and GGO ratio < 50%. Only undergone chemotherapy, LVSI and GGO ratio < 50% were significant poor predictors for survival. However, patients with metachronous lung adenocarcinoma and breast cancer had better disease-free survival and less tumor recurrence than patients with lung adenocarcinoma alone.

The complexity of interactions between female sex hormones and Chlamydia trachomatis infections

PURPOSE OF REVIEW

This review focuses specifically on the mechanisms by which female sex hormones, estrogen and progesterone, affect Chlamydia trachomatis infections in vivo and in vitro.

RECENT FINDINGS

Recent data support previous work indicating that estrogen enhances chlamydial development via multiple mechanisms. Progesterone negatively impacts Chlamydia infections also through multiple mechanisms, particularly by altering the immune response. Conflicting data exist regarding the effect of synthetic hormones, such as those found in hormonal contraceptives, on chlamydial infections.

SUMMARY

Numerous studies over the years have indicated that female sex hormones affect C. trachomatis infection. However, we still do not have a clear understanding of how these hormones alter Chlamydia disease transmission and progression. The studies reviewed here indicate that there are many variables that determine the outcome of Chlamydia/hormone interactions, including: 1) the specific hormone, 2) hormone concentration, 3) cell type or area of the genital tract, 4) hormone responsiveness of cell lines, and 5) animal models.

Mechanism of Rapid Nuclear Factor-E2-Related Factor 2 (Nrf2) Activation via Membrane-Associated Estrogen Receptors: Roles of NADPH Oxidase 1, Neutral Sphingomyelinase 2 and Epidermal Growth Factor Receptor (EGFR)

Membrane-associated estrogen receptors (ER)-α36 and G protein-coupled estrogen receptor (GPER) play important roles in the estrogen’s rapid non-genomic actions including stimulation of cell proliferation. Estrogen via these receptors induces rapid activation of transcription factor nuclear factor-E2-related factor 2 (Nrf2), a master regulator of detoxification and antioxidant systems, playing a key role in the metabolic reprogramming to support cell proliferation. This review highlights the possible mechanism underlying rapid Nrf2 activation via membrane-associated estrogen receptors by estrogen and phytoestrogens. Stimulation of ER-α36-GPER signaling complex rapidly induces Src-mediated transactivation of epidermal growth factor receptor (EGFR) leading to a kinase-mediated signaling cascade. We propose a novel hypothesis that ER-α36-GPER signaling initially induces rapid and temporal activation of NADPH oxidase 1 to generate superoxide, which subsequently activates redox-sensitive neutral sphingomyelinase 2 generating the lipid signaling mediator ceramide. Generation of ceramide is required for Ras activation and ceramide-protein kinase C ζ-casein kinase 2 (CK2) signaling. Notably, CK2 enhances chaperone activity of the Cdc37-Hsp90 complex supporting activation of various signaling kinases including Src, Raf and Akt (protein kinase B). Activation of Nrf2 may be induced by cooperation of two signaling pathways, (i) Nrf2 stabilization by direct phosphorylation by CK2 and (ii) EGFR-Ras-PI 3 kinase (PI3K)-Akt axis which inhibits glycogen synthase kinase 3β leading to enhanced nuclear transport and stability of Nrf2.

17α-Ethynylestradiol and 4-nonylphenol stimulate lung adenocarcinoma cell production in xenoestrogenic way

Lung cancer has been one of the major cancers leading to mortalities worldwide. In addition to smoking, estrogen is considered to play an important role in the lung cancer development because women have a higher proportion of adenocarcinoma than men. In the environment, there are many metabolites and waste products that mimic human estrogen structurally and functionally. 17α-Ethynylestradiol (EE2) which is used as an oral contraceptive is released into wastewater after being utilized. Moreover, 4-nonylphenol (NP) which is found in the petrochemical products and air pollutants reveals estrogenic activity. In the present study, 17β-estradiol (E2), EE2, and NP are administered to stimulate male lung adenocarcinoma cells (A549) and female lung adenocarcinoma cells (H1435). The results demonstrate that EE2 and NP stimulate A549 and H1435 cells proliferation in a dose- and time-dependent manner. Both estrogen receptors α and β are simultaneously activated. In response to estrogens, up-regulation of the epidermal growth factor receptor and extracellular signal-regulated kinase expression occurs. In conclusion, this is the first study to report that EE2 and NP exert a biotoxic effect to stimulate the proliferation of both male and female lung cancer cell in a dose- and time- dependent manner. The environmental hormones posing new challenges for lung cancer deserve further investigation.

G-Protein Coupled Estrogen Receptor in Breast Cancer

The G-protein coupled estrogen receptor (GPER), an alternate estrogen receptor (ER) with a structure distinct from the two canonical ERs, being ERα, and ERβ, is expressed in 50% to 60% of breast cancer tissues and has been presumed to be associated with the development of tamoxifen resistance in ERα positive breast cancer. On the other hand, triple-negative breast cancer (TNBC) constitutes 15% to 20% of breast cancers and frequently displays a more aggressive behavior. GPER is prevalent and involved in TNBC and can be a therapeutic target. However, contradictory results exist regarding the function of GPER in breast cancer, proliferative or pro-apoptotic. A better understanding of the GPER, its role in breast cancer, and the interactions with the ER and epidermal growth factor receptor will be beneficial for the disease management and prevention in the future.

Second Primary Lung Cancer After Breast Cancer: A Population-Based Study of 6,269 Women

Purpose: Breast cancer (BC) and lung cancer are the most two common cancers with highest morbidity and mortality for women. With prolonged survival, there comes the possibility that BC patients will develop second primary cancers. We evaluate the characteristics, incidence and survival of second primary non-small cell lung cancer (BC-NSCLC) and small cell lung cancer (BC-SCLC) after breast cancer. Patients and methods: Second primary lung cancer risks using standardized incidence ratios (SIRs) [95% confidence intervals (95% CIs)] were calculated among breast cancer patients in SEER-18 (2000-2014). Survival outcomes were also analyzed for both BC-NSCLC and BC-SCLC. Results: A total of 6,269 second lung cancer patients after a localized or regional BC were identified. The incidence rate was modestly higher compared to the general population (SIR = 1.03; 95%CI: 1.00-1.06). For ER-, PR- and HER2- groups, SIRs were 1.26, 1.16, 1.13, respectively (all p < 0.05). Triple negative breast cancer (TNBC) patients have an even higher incidence rate of lung cancer (SIR = 1.59, 95%CI: 1.29-1.94). Elevated SIRs were also observed among the following groups: within 1 year after BC diagnosed, a young age at BC diagnosed, black people, poorly or undifferentiated histological grade of breast cancer. Median survival (MST) after localized, regional and distant BC-NSCLC was 68.0, 26.0, and 6.0m. Five-year survival rates for BC-NSCLC were 53.9, 29.8 and 5.7% in each stage, which were significantly higher compared to first primary NSCLC (all p < 0.001). ER-/PR- or TNBC were unfavorable prognostic factors for BC-NSCLC. The survival rates of BC-SCLC were no significant different compared to first primary SCLC. Conclusion: BC patients, especially for TNBC, are at a high risk of developing second primary lung cancers. BC history may be a favorable prognostic factor for NSCLC (but not SCLC) patients. Clinicians should closely follow up BC patients with high-risk factors.

Cytoplasmic expression of estrogen receptor β may predict poor outcome of EGFR-TKI therapy in metastatic lung adenocarcinoma

There is growing evidence that estrogen receptors (ER) are expressed in lung cancer cells, and are able to interact with the epidermal growth factor receptor (EGFR) signaling pathway. However, data on the association between cytoplasmic ER expression and the response to EGFR-tyrosine kinase inhibitors (TKI) treatment are limited. The aim of the present study was to investigate the associations between ERα/ERβ expression and EGFR mutational status and response to TKI treatment in metastatic lung adenocarcinoma. A retrospective study of 126 consecutive patients with lung adenocarcinoma who were diagnosed with stage IV disease and had received EGFR-TKI treatment was conducted. ER expression was detected by immunohistochemistry. EGFR and GTPase KRas (KRAS) mutational statuses were evaluated by denaturing high performance liquid chromatography and PCR-restriction fragment length polymorphism, respectively. In the overall cohort of 126 lung adenocarcinoma samples analyzed, ERα expression in the nucleus of tumor cells was identified in 17 (18.9%) patients, whereas ERβ expression was identified in the nucleus (22/126, 17.5%) and cytoplasm (17/126, 13.5%). The nuclear expression of ERβ was positively associated with the degree of tumor differentiation (P=0.010). EGFR-sensitizing mutations were significantly associated with improved objective response rates (ORR), disease control rates (DCR), median progression-free survival (mPFS) and median overall survival (mOS) (P<0.001; P<0.001; P=0.003; and P=0.026, respectively). Patients with cytoplasmic ERβ expression exhibited non-significant poorer ORR, DCR, mPFS and mOS compared with patients without cytoplasmic ERβ expression (P=0.082; P=0.106; P=0.084; and P=0.119, respectively). However, the significant decrease of ORR, DCR and mPFS was observed in patients with coexisting cytoplasmic ERβ expression and EGFR-sensitizing mutations (P=0.030; P=0.009; and P=0.018, respectively) in comparison with the subgroup with EGFR sensitizing mutations but negative expression of cytoplasmic ERβ. A trend towards shorter mOS was also observed in patients with coexisting cytoplasmic ERβ expression and EGFR-sensitizing mutations (P=0.071). No KRAS mutations were identified in patients with cytoplasmic ERβ expression. Subsequent to adjusting for sex, smoking status and EGFR mutation status, the Cox repression analysis indicated that cytoplasmic expression of ERβ was a negative independent predictor for mPFS in the whole patient cohort (HR=1.870; 95% confidence interval 1.058–3.305; P=0.031). Cytoplasmic ERβ expression was negatively correlated with the efficacy of EGFR-TKI treatment for metastatic lung adenocarcinoma, particularly for patients with coexisting cytoplasmic ERβ expression and EGFR-sensitizing mutations. Cytoplasmic ERβ may be a promising marker to predict the outcome of EGFR-TKI treatment.

Membrane-bound estrogen receptor alpha initiated signaling is dynamin dependent in breast cancer cells

Background

Although membrane-associated estrogen receptors (mERs) have been known to play important role in steroid-induced signal transmission, we still know little about their function in the estrogen-induced proliferation of breast cancer cells.

Methods

In our current work we tried to separate membrane-initiated estrogen receptor signaling from the overall estrogenic effect in MCF-7 breast carcinoma cells. Re-analyzing expression data from multiple microarray experiments, we selected a set of key regulatory genes involved in proliferation regulation and estrogen signaling to monitor estrogen-induced transcription changes. We then compared these expression changes after 17β-estradiol and a membrane receptor selective estrogen–BSA treatment using quantitative real-time PCR. In order to follow receptor trafficking we used light and electron microscopy.

Results

Our quantitative real-time PCR results confirmed that the selective membrane receptor agonist, estrogen–BSA induces similarly pronounced expression changes regarding these genes as 17β-estradiol. Morphological study revealed that the membrane-bound form of classical estrogen receptor alpha is internalized after ligand binding via dynamin-dependent, caveola-mediated endocytosis. Inhibition of this internalization with dynamin inhibitor, dynasore practically abolished the regulatory effect of E2-BSA, suggesting that interaction and internalization with the scaffold protein is necessary for effective signaling.

Conclusions

The physiological role of plasma membrane estrogen receptor alpha is intensively studied, yet there are still several aspects of it to be resolved. The dynamin-dependent, ligand-mediated internalization of mERs seems to play an important role in estrogen signaling. Our results may serve as another example of how membrane initiated estrogen signaling and nuclear receptor initiated signaling overlap and form an intertwined system. 

Electronic supplementary material

The online version of this article (10.1186/s40001-018-0328-7) contains supplementary material, which is available to authorized users.

Genomic-Epidemiologic Evidence That Estrogens Promote Breast Cancer Development

Background: Estrogens are a prime risk factor for breast cancer, yet their causal relation to tumor formation remains uncertain. A recent study of 560 breast cancers identified 82 genes with 916 point mutations as drivers in the genesis of this malignancy. Because estrogens play a major role in breast cancer development and are also known to regulate the expression of numerous genes, we hypothesize that the 82 driver genes are likely to be influenced by estrogens, such as 17ß-estradiol (E2), and the estrogen receptor ESR1 (ERα). Because different types of tumors are characterized by unique sets of cancer driver genes, we also argue that the fraction of driver genes regulated by E2-ESR1 is lower in malignancies not associated with estrogens, e.g., acute myeloid leukemia (AML).Methods: We performed a literature search of each driver gene to determine its E2-ESR1 regulation.Results: Fifty-three of the 82 driver genes (64.6%) identified in breast cancers showed evidence of E2-ESR1 regulation. In contrast, only 19 of 54 mutated driver genes (35.2%) identified in AML were linked to E2-ESR1. Among the 916 driver mutations found in breast cancers, 813 (88.8%) were linked to E2-ESR1 compared with 2,046 of 3,833 in AML (53.4%).Conclusions: Risk assessment revealed that mutations in estrogen-regulated genes are much more likely to be associated with elevated breast cancer risk, while mutations in unregulated genes are more likely to be associated with AML.Impact: These results increase the plausibility that estrogens promote breast cancer development. Cancer Epidemiol Biomarkers Prev; 27(8); 899-907. ©2018 AACR.

Genistein reduces the activation of AKT and EGFR, and the production of IL6 in cholangiocarcinoma cells involving estrogen and estrogen receptors

Cholangiocarcinoma (CCA) is a malignant tumor of the biliary epithelium associated with Opisthorchis viverrini, primary sclerosing cholangitis and hepatitis viral infection. In the global population, men have higher incidence rates for CCA than women; thus, a gender disparity in the progression of chronic inflammation of the biliary duct leading to malignancy may involve the effects of estrogen (E2). Genistein (GE), a prominent phytoestrogen found in soy products, is an estrogen receptor β (ERβ) agonist and a tyrosine kinase inhibitor. The present study investigated the effects of GE on the growth of CCA cells by cell viability assay. The effects on signaling proteins were detected by western blot analysis and ELISA. Gene expression was examined by RT-qPCR. Two human intrahepatic CCA cell lines, HuCCA‑1 and RMCCA‑1, were utilized. GE (50‑200 µM) reduced the viability of the two cell lines, and also inhibited the activation of epidermal growth factor receptor (EGFR) and AKT, as evidenced by decreasing protein levels of phosphorylated (p)-EGFR (Tyr1173) and p‑AKT (Ser473), respectively. GE altered the mitogen‑activated protein kinase signaling cascade by mediating decreased protein levels of p‑p38 and increased protein levels of p‑ERK1/2. GE significantly decreased the levels of interleukin 6 (IL6) and induced the expression of inducible nitric oxide synthase (iNOS). GE also downregulated the expression of p‑ERα (Ser118) protein and ERα mRNA levels. Finally, GE induced the downregulation of the protein levels of ERβ. Of note, E2 deprivation potentiated the GE-induced reduction of p‑EGFR (Tyr1173) and total AKT proteins and production of IL6, and mediated the downregulation of GE-induced iNOS protein. In conclusion, GE inhibited the growth of human CCA cell lines by reducing the activation of EGFR and AKT, and by attenuating the production of IL6. E2 and ER were also involved in the growth-inhibitory effect of GE in CCA cells.

Expansion of Sphingosine Kinase and Sphingosine-1-Phosphate Receptor Function in Normal and Cancer Cells: From Membrane Restructuring to Mediation of Estrogen Signaling and Stem Cell Programming

Sphingolipids, sphingolipid metabolizing enzymes, and their receptors network are being recognized as part of the signaling mechanisms, which govern breast cancer cell growth, migration, and survival during chemotherapy treatment. Approximately 70% of breast cancers are estrogen receptor (ER) positive and, thus, rely on estrogen signaling. Estrogen activates an intracellular network composed of many cytoplasmic and nuclear mediators. Some estrogen effects can be mediated by sphingolipids. Estrogen activates sphingosine kinase 1 (SphK1) and amplifies the intracellular concentration of sphingosine-1-phosphate (S1P) in breast cancer cells during stimulation of proliferation and survival. Specifically, Estrogen activates S1P receptors (S1PR) and induces growth factor receptor transactivation. SphK, S1P, and S1PR expression are causally associated with endocrine resistance and progression to advanced tumor stages in ER-positive breast cancers in vivo. Recently, the network of SphK/S1PR was shown to promote the development of ER-negative cancers and breast cancer stem cells, as well as stimulating angiogenesis. Novel findings confirm and broaden our knowledge about the cross-talk between sphingolipids and estrogen network in normal and malignant cells. Current S1PRs therapeutic inhibition was indicated as a promising chemotherapy approach in non-responsive and advanced malignancies. Considering that sphingolipid signaling has a prominent role in terminally differentiated cells, the impact should be considered when designing specific SphK/S1PR inhibitors. This study analyzes the dynamic of the transformation of sphingolipid axis during a transition from normal to pathological condition on the level of the whole organism. The sphingolipid-based mediation and facilitation of global effects of estrogen were critically accented as a bridging mechanism that should be explored in cancer prevention.

Influence of estrogen in non-small cell lung cancer and its clinical implications

Lung cancer (LC) is the leading cause of cancer death in men worldwide and has significantly increased in women. Differences in non-small cell lung cancer (NSCLC) behavior, prognosis, and response to treatment have been reported by sex and hormonal status, with premenopausal women presenting the worst prognosis compared to postmenopausal women and men. Additionally, the use of hormonal replacement therapy significantly increases NSCLC mortality; supporting the role of estrogen signaling in the pathogenesis of LC. The mechanisms by which estrogen promotes lung carcinogenesis have not been fully elucidated. Estrogen, through its receptor, can stimulate LC cell proliferation, death resistance, angiogenesis, migration and metastasis. Estrogen also induces expression of pro-inflammatory proteins and ligands that promote tumor evasion, suggesting that estrogen might modify the microenvironment and anti-tumor immune response. Recent reports have shown an interaction between the epidermal growth factor receptor (EGFR) pathway and estrogen signaling in lung adenocarcinoma, whence, combined treatment based on tyrosine kinase inhibitors (TKIs) and antiestrogen therapy is beginning to be evaluated. This review focuses on the differences in NSCLC behavior by sex and hormonal status, highlighting the role of estrogen and its receptors in lung carcinogenesis and LC prognosis. Due to the importance of estrogen in NSCLC development and progression we finally discuss the potential of antiestrogen therapy in LC treatment and show the results from preclinical and clinical trials.

Erbin and ErbB2 play roles in the sexual differentiation of the song system nucleus HVC in bengalese finches (Lonchura Striata var. domestica)

Song control nuclei have distinct sexual differences in songbirds. However, the mechanism that underlies the sexual differentiation of song nuclei is still not well understood. Using a combination of anatomical, pharmacological, genetic, and behavioral approaches, the present study investigated the role of erbb2 (a homolog of the avian erythroblastic leukemia viral oncogene homolog 2) and the erbb2-interacting gene, erbin, in the sexual differentiation of the song nucleus HVC in the Bengalese finch. We first found that both erbin and erbb2 were expressed in the developing HVC at posthatch day (PHD) 15 in a male-biased fashion using qRT-PCR and in situ hybridization. Following the addition of a pharmaceutical inhibitor of the ErbB2 signaling pathway to the culture medium, cell proliferation in the cultured ventricle zone (VZ) that overlies the developing HVC decreased significantly. After the injection of erbin- or erbb2-interfering lentiviruses into the HVC and its overlying VZ at PHD 15, the cell proliferation in the VZ at PHD 24, the number of the differentiated neurons (Hu⁺ /BrdU⁺ or NeuN⁺ /BrdU⁺ ) in the HVC at PHD 31 or PHD 130, and the number of RA-projecting cells at PHD 130 all decreased significantly. Additionally, the adult songs displayed serious abnormalities. Finally, 173 male-biased genes were expressed in the developing HVC at PHD 15 using cDNA microarrays, of which 27.2% were Z-linked genes and approximately 20 genes were involved in the Erbin- or ErbB2-related signaling pathways. Our results provide some specific genetic factors that contribute to neurogenesis and sex differentiation in a song nucleus of songbirds. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 15-38, 2018.

Estrogen and cigarette sidestream smoke particulate matter exhibit ERα-dependent tumor-promoting effects in lung adenocarcinoma cells

Estrogen and secondhand smoke are key risk factors for nonsmoking female lung cancer patients who frequently have lung adenocarcinoma and show tumor estrogen receptor α (ERα) expression. We speculated that estrogen and secondhand smoke might cause harmful effects via ERα signaling. Our results showed that 17β-estradiol (E2), the primary form of endogenous estrogen, exacerbated proliferation, migration, and granzyme B resistance of lung adenocarcinoma cells in an ERα-dependent manner. Cigarette sidestream smoke particulate matter (CSSP), the major component of secondhand smoke, could activate ERα activity dose dependently in human lung adenocarcinoma cells. The estrogenic activity of CSSP was abolished by an ERα-selective antagonist. CSSP regulated the nuclear entry, phosphorylation, and turnover of ERα similarly to E2. Furthermore, CSSP enhanced E2-stimulated ERα activity and Ser118 phosphorylation even when ERα became saturated with E2. Activation of ERα by CSSP required GSK3β activity, but not involving polycyclic aromatic hydrocarbons, reactive oxygen species, calcium, epidermal growth factor receptor, and PI3K/Akt. Although CSSP possessed cytotoxicity, ERα-expressing cells grew and migrated faster than nonexpressing cells on recovery from CSSP exposure as observed in E2-pretreated cells. Knockdown of ERα by siRNA diminished E2- and CSSP-stimulated cell migration. Twenty-one genes, including SERPINB9, were identified to be upregulated by both E2 and CSSP via ERα. Increased SERPINB9 expression was accompanied with increased resistance to granzyme B-mediated apoptosis. This study demonstrates that estrogen has ERα-dependent tumor-promoting activity. CSSP acts like estrogen and shows a potential to enhance estrogen-induced ERα action.

Estrogen, Estrogen Receptor and Lung Cancer

Estrogen has been postulated as a contributor for lung cancer development and progression. We reviewed the current knowledge about the expression and prognostic implications of the estrogen receptors (ER) in lung cancer, the effect and signaling pathway of estrogen on lung cancer, the hormone replacement therapy and lung cancer risk and survival, the mechanistic relationship between the ER and the epidermal growth factor receptor (EGFR), and the relevant clinical trials combining the ER antagonist and the EGFR antagonist, to investigate the role of estrogen in lung cancer. Estrogen and its receptor have the potential to become a prognosticator and a therapeutic target in lung cancer. On the other hand, tobacco smoking aggravates the effect of estrogen and endocrine disruptive chemicals from the environment targeting ER may well contribute to the lung carcinogenesis. They have gradually become important issues in the course of preventive medicine.