Ca2+ channel subunit α 1D promotes proliferation and migration of endometrial cancer cells mediated by 17β-estradiol via the G protein-coupled estrogen receptor

Deciphering odontogenic myxoma: the role of copy number variations as diagnostic signatures

In light of the lack of reliable molecular markers for odontogenic myxoma (OM), the detection of copy number variation (CNV) may present a more objective method for assessing ambiguous cases. In this study, we employed multiregional microdissection sequencing to integrate morphological features with genomic profiling. This allowed us to reveal the CNV profiles of OM and compare them with dental papilla (DP), dental follicle (DF), and odontogenic fibroma (OF) tissues. We identified a distinct and robustly consistent CNV pattern in 93.75% (30/32) of OM cases, characterized by CNV gain events in chromosomes 4, 5, 8, 10, 12, 16, 17, 20, and 21. This pattern significantly differed from the CNV patterns observed in DP, DF, and OF. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated potential links between this CNV patterns and the calcium signaling pathway and salivary secretion, while Gene Ontology (GO) term analysis implicated CNV patterns in tumor adhesion, tooth development, and cell proliferation. Comprehensive CNV analysis accurately identified a case that was initially disputable between OF and OM as OM. Our findings provide a reliable diagnostic clue and fresh insights into the molecular biological mechanism underlying OM.

The L-type calcium channel CaV1.3: A potential target for cancer therapy

Cancer remains a prominent cause to life expectancy, and targeted cancer therapy stands as a pivotal approach in contemporary therapy. Calcium (Ca2+) signalling plays a multifaceted role in cancer progression, such as proliferation, invasion and distant metastasis. Otherwise, it also exerts an important influence on the efficacy of clinical treatment, including cancer therapy resistance. In this review we discuss the role of the L-type calcium channel CaV1.3 (calcium voltage-gated channel subunit alpha1 D) in different types of cancers, highlighting its potential as a therapeutic target for certain cancer types. The development of selective blockers of the CaV1.3 channel has been of great interest and is expected to be a new option for the treatment of cancers such as prostate cancer and endometrial cancer. We present the pharmacological properties of CaV1.3 and the current status of selective blocker development, and analyse the challenges and possible directions for breakthroughs in the development of tailored medicines.

Micro- and Macronutrients in Endometrial Cancer-From Metallomic Analysis to Improvements in Treatment Strategies

Endometrial cancer is reported to be one of the most prevalent cancers of the female reproductive organs worldwide, with increasing incidence and mortality rates over the past decade. Early diagnosis is critical for effective treatment. Recently, there has been a growing focus on the role of nutrition and micronutrient and macronutrient status in patients with gynecologic cancers, including endometrial cancer. In the following paper, we have conducted an in-depth narrative literature review with the aim of evaluating the results of metallomic studies specifically concerning the micro- and macronutrient status of patients with endometrial cancer. The main objective of the paper was to analyze the results regarding the nutritional status of endometrial cancer patients and describe the role of chosen elements in the onset and progression of endometrial carcinogenesis. Further, we have focused on the evaluation of the usage of the described elements in the potential treatment of the abovementioned cancer, as well as the possible prevention of cancer considering proper supplementation of chosen elements in healthy individuals. Calcium supplementation has been proposed to reduce the risk of endometrial cancer, although some studies offer conflicting evidence. Deficiencies in phosphorus, selenium, and zinc have been inversely associated with endometrial cancer risk, suggesting they may play a protective role, whereas excessive levels of iron, copper, and cadmium have been positively correlated with increased risk. However, the molecular mechanisms by which these elements affect endometrial carcinogenesis are not fully understood, and current findings are often contradictory. Further research is needed to clarify these relationships and to evaluate the potential of nutritional interventions for the prevention and treatment of endometrial cancer.

Ion Channels and Personalized Medicine in Gynecological Cancers

Targeted therapy against cancer plays a key role in delivering safer and more efficient treatments. In the last decades, ion channels have been studied for their participation in oncogenic processes because their aberrant expression and/or function have been associated with different types of malignancies, including ovarian, cervical, and endometrial cancer. The altered expression or function of several ion channels have been associated with tumor aggressiveness, increased proliferation, migration, invasion, and metastasis of cancer cells and with poor prognosis in gynecological cancer patients. Most ion channels are integral membrane proteins easily accessible by drugs. Interestingly, a plethora of ion channel blockers have demonstrated anticancer activity. Consequently, some ion channels have been proposed as oncogenes, cancer, and prognostic biomarkers, as well as therapeutic targets in gynecological cancers. Here, we review the association of ion channels with the properties of cancer cells in these tumors, which makes them very promising candidates to be exploited in personalized medicine. The detailed analysis of the expression pattern and function of ion channels could help to improve the clinical outcomes in gynecological cancer patients.

Effects of short-term exposure to volatile pesticide dichlorvos on the olfactory systems in Spodoptera litura: Calcium homeostasis, synaptic plasticity and apoptosis

Volatile pesticides are a growing environmental and public health concern. However, little attention has been paid to its olfactory neurotoxic effect on pests and non-target organisms. Dichlorvos is a widely used organophosphorus fumigant that is ubiquitous in the environment. This study aims to explore the mode of action of the volatile dichlorvos-mediated olfactory impairment using a lepidopteran insect Spodoptera litura as a model. It was indicated that electroantennogram amplitudes of the male moths' response to sex pheromones and phenylacetaldehyde were reduced by approximately 20 % after 12-h fumigation exposure. RNA-Sequencing analysis revealed that down-regulation of trypsin and CLIC2 might be responsible for inhibition of odor recognition in the antenna, the peripheral olfactory tissue. In the head, 822 (84.05 %) of the 978 differentially expressed genes (DEGs) were up-regulated, of which seven DEGs encoding transcription factors may mainly modulate the stress-regulatory networks. Combining transcriptome with brain calcium imaging and Annexin V-mCherry staining experiments showed that volatile dichlorvos mainly disrupts Ca²⁺ homeostasis and synaptic plasticity, induces apoptosis in the central nervous system, and further leads to olfactory dysfunction. Overall, this study highlighted a comprehensive work model for dichlorvos-induced olfactory impairment in S. litura and may provide insights into toxic effects of airborne organophosphates on non-target organisms.

Implications of estrogen and its receptors in colorectal carcinoma

Estrogens have been implicated in the pathogenesis of various cancer types, including colorectal carcinoma (CRC). Estrogen receptors such as ERα and ERβ activate intracellular signaling cascades followed by binding to estrogen, resulting in important changes in cellular behaviors. The nuclear estrogen receptors, i.e. ERβ and ERα are responsible for the genomic actions of estrogens, whereas the other receptor, such as G protein-coupled estrogen receptor (GPER) regulates rapid non-genomic actions, which lead to secondary gene expression changes in cells. ERβ, the predominant estrogen receptor expressed in both normal and non-malignant colonic epithelium, has protective roles in colon carcinogenesis. ERβ may exert the anti-tumor effect through selective activation of pro-apoptotic signaling, increasing DNA repair, inhibiting expression of oncogenes, regulating cell cycle progression, and also by changing the micro-RNA pool and DNA-methylation. Thus, a better understanding of the underlying mechanisms of estrogen and its receptors in CRC pathogenesis could provide a new horizon for effective therapeutic development. Furthermore, using synthetic or natural compounds as ER agonists may induce estrogen-mediated anti-cancer activities against colon cancer. In this study, we report the most recent pre-clinical and experimental evidences related to ERs in CRC development. Also, we reviewed the actions of naturally occurring and synthetic compounds, which have a protective role against CRC development by acting as ER agonist.

Metabolic disorders sensitise endometrial carcinoma through endoplasmic reticulum stress

BACKGROUND

Metabolic disorder is considered a well-established risk factor for endometrial carcinoma (EC). However, the mechanism remains unclear. Insulin resistance and excessive flux of free fatty acids serve as fundamental pathogenic factors in metabolic disorders, including obesity and type 2 diabetes. The aim of this study was to test the correlation between insulin resistance and dyslipidaemia in EC and to determine the effect of insulin and saturated fatty acids on EC cells.

METHODS

A retrospective study on the medical records of patients with EC and RNA-seq from the TCGA database analysed with edgR and Gene Ontology (GO) were used to assess the correlation of dyslipidaemia and diabetes as well as obesity. Crystal violet assays and CCK-8 assays were used to detect the proliferation of EC cells, and Annexin V-PI was used to examine apoptosis. Transient changes in mitochondrial Ca²⁺ and reactive oxygen species (ROS) were monitored via confocal microscopy. DNA damage was assessed by comet assays. Changes in signalling pathways were detected via phospho-kinase array. western blotting was used to assess the molecular changes in endoplasmic reticulum (ER) stress and DNA damage.

RESULTS

We found that glucose metabolism disorders accompanied dyslipidaemia in patients with EC. As a key regulator of glucose metabolism disorders, insulin promoted DNA damage, ROS and Ca²⁺ homoeostasis imbalance in a panel of established EC cell lines. Interestingly, excessive insulin boosted saturated fatty acid-induced pro-apoptotic effects in EC cells. Furthermore, our data showed that insulin synergised with saturated fatty acids to activate the mechanistic target of rapamycin kinase/70 kDa ribosomal protein S6 kinase (mTOR/p70S6K) pathway and ER stress, resulting in Ca²⁺ release from ER and unfolded protein response (UPR) activation, which contributed to combined insulin and saturated fatty acid treatment-induced apoptosis and tumour progression.

CONCLUSIONS

Our data are the first to illustrate that impaired glucose metabolism accelerates dyslipidaemia-promoted EC progression, which is attributed to hyperinsulinaemia and saturated fatty acid-induced Ca²⁺ dyshomoeostasis and UPR activation in EC cells via ER stress.

The distinguishing electrical properties of cancer cells

In recent decades, medical research has been primarily focused on the inherited aspect of cancers, despite the reality that only 5-10% of tumours discovered are derived from genetic causes. Cancer is a broad term, and therefore it is inaccurate to address it as a purely genetic disease. Understanding cancer cells' behaviour is the first step in countering them. Behind the scenes, there is a complicated network of environmental factors, DNA errors, metabolic shifts, and electrostatic alterations that build over time and lead to the illness's development. This latter aspect has been analyzed in previous studies, but how the different electrical changes integrate and affect each other is rarely examined. Every cell in the human body possesses electrical properties that are essential for proper behaviour both within and outside of the cell itself. It is not yet clear whether these changes correlate with cell mutation in cancer cells, or only with their subsequent development. Either way, these aspects merit further investigation, especially with regards to their causes and consequences. Trying to block changes at various levels of occurrence or assisting in their prevention could be the key to stopping cells from becoming cancerous. Therefore, a comprehensive understanding of the current knowledge regarding the electrical landscape of cells is much needed. We review four essential electrical characteristics of cells, providing a deep understanding of the electrostatic changes in cancer cells compared to their normal counterparts. In particular, we provide an overview of intracellular and extracellular pH modifications, differences in ionic concentrations in the cytoplasm, transmembrane potential variations, and changes within mitochondria. New therapies targeting or exploiting the electrical properties of cells are developed and tested every year, such as pH-dependent carriers and tumour-treating fields. A brief section regarding the state-of-the-art of these therapies can be found at the end of this review. Finally, we highlight how these alterations integrate and potentially yield indications of cells' malignancy or metastatic index.

Intercommunication between Voltage-Gated Calcium Channels and Estrogen Receptor/Estrogen Signaling: Insights into Physiological and Pathological Conditions

Voltage-gated calcium channels (VGCCs) and estrogen receptors are important cellular proteins that have been shown to interact with each other across varied cells and tissues. Estrogen hormone, the ligand for estrogen receptors, can also exert its effects independent of estrogen receptors that collectively constitute non-genomic mechanisms. Here, we provide insights into the VGCC regulation by estrogen and the possible mechanisms involved therein across several cell types. Notably, most of the interaction is described in neuronal and cardiovascular tissues given the importance of VGCCs in these electrically excitable tissues. We describe the modulation of various VGCCs by estrogen known so far in physiological conditions and pathological conditions. We observed that in most in vitro studies higher concentrations of estrogen were used while a handful of in vivo studies used meager concentrations resulting in inhibition or upregulation of VGCCs, respectively. There is a need for more relevant physiological assays to study the regulation of VGCCs by estrogen. Additionally, other interacting receptors and partners need to be identified that may be involved in exerting estrogen receptor-independent effects of estrogen.

Ion Channels in Endometrial Cancer

Simple Summary

Uterine or endometrial cancer is one of the most common types of cancer among the female population. Different alterations of molecules are related to many types of cancer. Some molecules called ion channels have been described as involved in the development of cancer, including endometrial cancer. We review the scientific evidence about the involvement of the ion channels in endometrial cancer and how some treatments can be developed with these molecules as a target. Even though they are involved in the progression of endometrial cancer, since they are present throughout the whole body, some possible treatments based on these could be studied.

Abstract

Uterine or endometrial cancer (EC) is the sixth most common neoplasia among women worldwide. Cancer can originate from a myriad of causes, and increasing evidence suggests that ion channels (IC) play an important role in the process of carcinogenesis, taking part in many pathways such as self-sufficiency in growth signals, proliferation, evasion of programmed cell death (apoptosis), angiogenesis, cell differentiation, migration, adhesion, and metastasis. Hormones and growth factors are well-known to be involved in the development and/or progression of many cancers and can also regulate some ion channels and pumps. Since the endometrium is responsive and regulated by these factors, the ICs could make an important contribution to the development and progression of endometrial cancer. In this review, we explore what is beyond (ion) flow regulation by investigating the role of the main families of ICs in EC, including as possible targets for EC treatment.

Identification and Validation of an m7G-Related lncRNAs Signature for Prognostic Prediction and Immune Function Analysis in Endometrial Cancer

Background: N7-methylguanosine is a novel kind of internal modification that is widespread in human mRNA. The relationship between m7G-related lncRNAs (MRL) and endometrial cancer remains unknown. The aim of our study is to explore a predictive prognosis MRL signature in endometrial cancer and identify the underlying biological mechanism. Methods: We obtained RNA-seq profiles, clinical data, and information on somatic mutations from the TCGA database and obtained m7G-related genes from a previous study. MRLs were identified through a co-expression network. The prognostic model was constructed based on 10 m7G-related lncRNAs. Differentially expressed genes between low- and high-risk groups were identified for further analysis, consisting of functional enrichment analysis, immune function analysis, somatic mutation analysis, and potential drugs exploration. Results: We constructed a 10-MRLs signature. According to the risk score, the signature was classified into high- and low-risk groups. The signature had a reliable capacity for predicting the prognosis of endometrial cancer patients. The findings about differentially expressed genes were also of great significance for therapeutic treatments for endometrial cancer and gave novel insights into exploring the underlying molecular mechanism. Conclusion: The prognostic model based on 10 MRLs is a reliable and promising approach for predicting clinical outcomes and suggesting therapeutic methods for endometrial cancer patients.

Store-Operated Ca2+ Entry Contributes to Piezo1-Induced Ca2+ Increase in Human Endometrial Stem Cells

Endometrial mesenchymal stem cells (eMSCs) are a specific class of stromal cells which have the capability to migrate, develop and differentiate into different types of cells such as adipocytes, osteocytes or chondrocytes. It is this unique plasticity that makes the eMSCs significant for cellular therapy and regenerative medicine. Stem cells choose their way of development by analyzing the extracellular and intracellular signals generated by a mechanical force from the microenvironment. Mechanosensitive channels are part of the cellular toolkit that feels the mechanical environment and can transduce mechanical stimuli to intracellular signaling pathways. Here, we identify previously recorded, mechanosensitive (MS), stretch-activated channels as Piezo1 proteins in the plasma membrane of eMSCs. Piezo1 activity triggered by the channel agonist Yoda1 elicits influx of Ca²⁺, a known modulator of cytoskeleton reorganization and cell motility. We found that store-operated Ca²⁺ entry (SOCE) formed by Ca²⁺-selective channel ORAI1 and Ca²⁺ sensors STIM1/STIM2 contributes to Piezo1-induced Ca²⁺ influx in eMSCs. Particularly, the Yoda1-induced increase in intracellular Ca²⁺ ([Ca²⁺]_i) is partially abolished by 2-APB, a well-known inhibitor of SOCE. Flow cytometry analysis and wound healing assay showed that long-term activation of Piezo1 or SOCE does not have a cytotoxic effect on eMSCs but suppresses their migratory capacity and the rate of cell proliferation. We propose that the Piezo1 and SOCE are both important determinants in [Ca²⁺]_i regulation, which critically affects the migratory activity of eMSCs and, therefore, could influence the regenerative potential of these cells.

Estrogen-Induced Extracellular Calcium Influx Promotes Endometrial Cancer Progress by Regulating Lysosomal Activity and Mitochondrial ROS

Objective

Calcium is present in serum mainly in filterable and bound forms, and Ca²⁺ is a major key to modulate signaling pathways that control oncogenesis and oncochannels associated with several types of cancer. However, the biological significance of serum calcium and its related mechanism with estrogen in endometrial cancer (EC) still remains elusive. This study aims to ascertain the relationship between serum calcium and clinicopathology in EC.

Methods

Retrospective assessment of a total of 502 patients diagnosed with EC after surgery in Peking University People's Hospital from 2010 to 2018. Preoperative serum ionized calcium and the albumin corrected calcium was calculated in quartiles for various postoperative clinicopathological characteristics, logistic regression adjusted for potential confounders. Intracellular calcium homeostasis change induced by estrogen was detected by confocal analysis. Downstream pathways were analyzed by transcriptome and proteomics. Mitochondrial Ca²⁺ and ROS (reactive oxygen species) level was detected by confocal and flow cytometry. Lysosomal morphological and membrane changes were verified by confocal or Western blot assays.

Results

High level of albumin-corrected serum calcium was significantly correlated with EC clinicopathological characteristics progression include lymph vascular space invasion, lymph nodes metastasis, myometrial invasion, and cervical invasion. Calcium homeostasis regulated by estrogen in EC cells derived from extracellular calcium influx but not the release of the endoplasmic reticulum. Proteomic and bioinformatic analysis revealed the calcium influx might be involved in the regulation of autophagy and mitochondrial-related pathways. Mechanistic investigation demonstrated that calcium influx acted on the function of mitochondrial ROS and lysosomal activity.

Conclusion

Our findings revealed that serum calcium level was significantly related to poor outcomes. The extracellular calcium influx induced by estrogen was targeted to mitochondrial ROS and lysosome activity, which should be oriented to improve EC therapeutic strategies.

Alterations in the Ca2+ toolkit in oesophageal adenocarcinoma

Aim:

To investigate alterations in transcription of genes, encoding Ca²⁺ toolkit proteins, in oesophageal adenocarcinoma (OAC) and to assess associations between gene expression, tumor grade, nodal-metastatic stage, and patient survival.

Methods:

The expression of 275 transcripts, encoding components of the Ca²⁺ toolkit, was analyzed in two OAC datasets: the Cancer Genome Atlas [via the University of Alabama Cancer (UALCAN) portal] and the oesophageal-cancer, clinical, and molecular stratification [Oesophageal Cancer Clinical and Molecular Stratification (OCCAMS)] dataset. Effects of differential expression of these genes on patient survival were determined using Kaplan-Meier log-rank tests. OAC grade- and metastatic-stage status was investigated for a subset of genes. Adjustment for the multiplicity of testing was made throughout.

Results:

Of the 275 Ca²⁺-toolkit genes analyzed, 75 displayed consistent changes in expression between OAC and normal tissue in both datasets. The channel-encoding genes, N-methyl-D-aspartate receptor 2D (GRIN2D), transient receptor potential (TRP) ion channel classical or canonical 4 (TRPC4), and TRP ion channel melastatin 2 (TRPM2) demonstrated the greatest increase in expression in OAC in both datasets. Nine genes were consistently upregulated in both datasets and were also associated with improved survival outcomes. The 6 top-ranking genes for the weighted significance of altered expression and survival outcomes were selected for further analysis: voltage-gated Ca²⁺ channel subunit α 1D (CACNA1D), voltage-gated Ca²⁺ channel auxiliary subunit α2 δ4 (CACNA2D4), junctophilin 1 (JPH1), acid-sensing ion channel 4 (ACCN4), TRPM5, and secretory pathway Ca²⁺ ATPase 2 (ATP2C2). CACNA1D, JPH1, and ATP2C2 were also upregulated in advanced OAC tumor grades and nodal-metastatic stages in both datasets.

Conclusions:

This study has unveiled alterations of the Ca²⁺ toolkit in OAC, compared to normal tissue. Such Ca²⁺ signalling findings are consistent with those from studies on other cancers. Genes that were consistently upregulated in both datasets might represent useful markers for patient diagnosis. Genes that were consistently upregulated, and which were associated with improved survival, might be useful markers for patient outcome. These survival-associated genes may also represent targets for the development of novel chemotherapeutic agents.

Environmental level bisphenol A accelerates alterations of the reno-cardiac axis by the MAPK cascades in male diabetic rats: An analysis based on transcriptomic profiling and bioinformatics

In humans and animal models, the kidneys and cardiovascular systems are negatively affected by BPA from the environment. It is considered that BPA have some potential estrogen-like and non-hormone-like properties. In this study, RNA-sequencing and its-related bioinformatics was used as the basic strategy to clarify the characteristic mechanisms of kidney-heart axis remodeling and dysfunction in diabetic male rats under BPA exposure. We found that continuous BPA exposure in diabetic rats aggravated renal impairment, and caused hemodynamic disorders and dysfunctions. There were 655 and 125 differentially expressed genes in the kidney and heart, respectively. For the kidneys, functional annotation and enrichment, and gene set enrichment analyses identified bile acid secretion related to lipid synthesis and transport, and MAPK cascade pathways. For the heart, these bioinformatics analyses clearly pointed to MAPKs pathways. A total of 12 genes and another total of 6 genes were identified from the kidney tissue and heart tissue, respectively. Western blotting showed that exposure to BPA activated MAPK cascades in both organs. In this study, the exacerbated remodeling of diabetic kidney-heart axis under BPA exposure and diabetes might occur through hemodynamics, metabolism disorders, and the immune-inflammatory response, as well as continuous estrogen-like stimulation, with focus on the MAPK cascades.

A "Janus" face of the RASSF4 signal in cell fate

RASSF4 (Ras-association domain family 4) is a protein-coding gene, regarded as a tumor suppressor regulated by DNA methylation. However, RASSF4 acts as a "Janus" in cell fate: death and survival. This review article focuses on the regulatory mechanisms of RASSF4 on cell death and cell survival and puts forward a comprehensive analysis of the relevant signaling pathways. The participation of RASSF4 in the regulation of intracellular store-operated Ca²⁺ entry also affects cell survival. Moreover, the mechanism of inducing abnormal expression of RASSF4 was summarized. We highlight recent advances in our knowledge of RASSF4 function in the development of cancer and other clinical diseases, which may provide insight into the controversial functions of RASSF4 and its potential application in disease therapy.

Advances in the study of cancer metastasis and calcium signaling as potential therapeutic targets

Metastasis is still the primary cause of cancer-related mortality. However, the underlying mechanisms of cancer metastasis are not yet fully understood. Currently, the epithelial-mesenchymal transition, metabolic remodeling, cancer cell intercommunication and the tumor microenvironment including diverse stromal cells, are reported to affect the metastatic process of cancer cells. Calcium ions (Ca²⁺) are ubiquitous second messengers that manipulate cancer metastasis by affecting signaling pathways. Diverse transporter/pump/channel-mediated Ca²⁺ currents form Ca²⁺ oscillations that can be decoded by Ca²⁺-binding proteins, which are promising prognostic biomarkers and therapeutic targets of cancer metastasis. This paper presents a review of the advances in research on the mechanisms underlying cancer metastasis and the roles of Ca²⁺-related signals in these events.

A ten-gene methylation signature as a novel biomarker for improving prediction of prognosis and indicating gene targets in endometrial cancer

Endometrial cancer (EC) is a common female reproductive tumor worldwide. Nonetheless, the pathogenesis of EC still remains ambiguous and associated epigenetic mechanism still to be explored. The goal of this study is to investigate whether gene methylation signature is associated with overall survival (OS) for EC patients. In this study, a 10-gene methylation risk model was built and the OS in high- and low-risk groups was significant different. The area under the ROC curve (AUC) of this model was 0.856 at 5 years survival. The nomogram could accurately predict the OS in EC patients, with concordance index and AUC at 5 year survival reached 0.796 and 0.792, respectively. Furthermore, we verified the nomogram with 24 patients in our center and the Kaplan-Meier survival curve also proved to be significantly different (p < 0.01). WGCNA revealed a key gene group for the model and further bioinformatics analysis indicated 6 genes as the hub genes in the module. Knockdown of MMP12 inhibited the proliferation, invasion and metastasis of EC cells. After all, a methylation signature and a nomogram based on this signature were constructed, and they could both predict survival in patients with EC. Moreover, WGCNA model identified MMP12 as a potential target for the treatment of EC.

A Novel Transcription Factor-Based Prognostic Signature in Endometrial Cancer: Establishment and Validation

Background

Endometrial cancer (EC) is a common malignancy of the female reproductive system worldwide. Increasing evidence has suggested that many transcription factors are aberrantly expressed in various cancers. This study aimed to develop a transcription factor-based prognostic signature for EC.

Methods

Gene expression data and clinical data of EC patients were downloaded from The Cancer Genome Atlas (TCGA) database. Univariate Cox regression and Multivariate Cox regression analysis was used to construct a prognostic signature. Then, the efficacy of the prognostic signature was validated in a training cohort, testing cohort and then the entire cohort. Correlations between clinical features and the model were also analyzed, and a nomogram based on the multivariate Cox analysis was developed. Furthermore, we verified the effect of a key transcription factor, E2F1, on biological functions of EC in vitro.

Results

We developed a nine-transcription factor (MSX1, HOXB9, E2F1, DLX4, BNC2, DLX2, PDX1, POU3F2, and FOXP3) prognostic signature. Compared with those in the low-risk group, patients in the high-risk group had worse clinical outcomes. The area under the curve (AUC) of this prognostic signature for 5-year survival was 0.806 in the training cohort, 0.710 in the testing cohort and 0.761 in the entire cohort. Gene set enrichment analysis (GSEA) revealed a correlation between the prognostic signature and various cancer signaling pathways, and a hub transcription factor regulatory network was constructed. The prognostic signature was confirmed to have independent predictive value. Finally, a nomogram based on the prognostic signature and clinical independent prognostic factors was also established and performed well according to the calibration curves. Further, knockdown of E2F1 inhibited invasion and metastasis of EC cells.

Conclusion

Our study developed and validated a transcription factor-based prognostic signature that accurately predicts prognosis of EC patients. Moreover, E2F1 may represent a potential target for the treatment of EC.

Calcium and TRPV4 promote metastasis by regulating cytoskeleton through the RhoA/ROCK1 pathway in endometrial cancer

Transient receptor potential vanilloid 4 (TRPV4) is a calcium-permeable cation channel that has been associated with several types of cancer. However, its biological significance, as well as its related mechanism in endometrial cancer (EC) still remains elusive. In this study, we examined the function of calcium in EC, with a specific focus on TRPV4 and its downstream pathway. We reported here on the findings that a high level of serum ionized calcium was significantly correlated with advanced EC progression, and among all the calcium channels, TRPV4 played an essential role, with high levels of TRPV4 expression associated with cancer progression both in vitro and in vivo. Proteomic and bioinformatics analysis revealed that TRPV4 was involved in cytoskeleton regulation and Rho protein pathway, which regulated EC cell migration. Mechanistic investigation demonstrated that TRPV4 and calcium influx acted on the cytoskeleton via the RhoA/ROCK1 pathway, ending with LIMK/cofilin activation, which had an impact on F-actin and paxillin (PXN) levels. Overall, our findings indicated that ionized serum calcium level was significantly associated with poor outcomes and calcium channel TRPV4 should be targeted to improve therapeutic and preventive strategies in EC.

Increased Serum Calcium Level Promotes the Risk of Lymph Node Metastasis in Endometrial Cancer

Purpose

The early predictive values of diagnostic markers for lymph node metastasis (LNM) in endometrial cancer (EC) are still unclear at present. The purpose of this study is to explore the relationship between serum calcium and LNM in EC.

Methods

We identified all patients with EC who underwent surgery between January 2012 and December 2016. Patient characteristics and various preoperative clinicopathologic data were obtained from medical records and were reviewed retrospectively. These patients were divided into two groups according to the pathology of their lymph node. Logistic regression models analyzed the relationship between the ionized calcium and LNM of EC patients, while adjusting for the potential confounders.

Results

A total of 448 patients were assessed. Univariate analysis showed that ionized calcium, CA125 level, tumor grade, peritoneal cytology, FIGO stage, histological type, LVSI, and myometrial invasion were positively correlated with LNM (all P<0.05). The risk of LNM increased with the promotion of serum ionized calcium (P for trend <0.01). Ionized calcium level was significant before and after the adjustment of cofounders (unadjusted: OR=11.9, 95% CI: 4.8-29.6, P< 0.01; model I: OR=11.3, 95% CI: 4.5-28.8, P< 0.01; model II: OR=5.2, 95% CI: 1.6-17.2, P< 0.05). Additionally, the risk of ionized calcium was especially evident in patients whose age was older than 60, BMI<28 kg/m², grade 3, negative peritoneal cytology and endometrioid endometrial adenocarcinoma.

Conclusion

Ionized calcium level was highly associated with LNM in EC and acted as a potential biomarker in predicting the risk of LNM in EC.

Exploring the Therapeutic Potential of Membrane Transport Proteins: Focus on Cancer and Chemoresistance

Improving the therapeutic efficacy of conventional anticancer drugs represents the best hope for cancer treatment. However, the shortage of druggable targets and the increasing development of anticancer drug resistance remain significant problems. Recently, membrane transport proteins have emerged as novel therapeutic targets for cancer treatment. These proteins are essential for a plethora of cell functions ranging from cell homeostasis to clinical drug toxicity. Furthermore, their association with carcinogenesis and chemoresistance has opened new vistas for pharmacology-based cancer research. This review provides a comprehensive update of our current knowledge on the functional expression profile of membrane transport proteins in cancer and chemoresistant tumours that may form the basis for new cancer treatment strategies.

Mechanical tumor microenvironment and transduction: cytoskeleton mediates cancer cell invasion and metastasis

Metastasis is a complicated, multistep process that is responsible for over 90% of cancer-related death. Metastatic disease or the movement of cancer cells from one site to another requires dramatic remodeling of the cytoskeleton. The regulation of cancer cell migration is determined not only by biochemical factors in the microenvironment but also by the biomechanical contextual information provided by the extracellular matrix (ECM). The responses of the cytoskeleton to chemical signals are well characterized and understood. However, the mechanisms of response to mechanical signals in the form of externally applied force and forces generated by the ECM are still poorly understood. Furthermore, understanding the way cellular mechanosensors interact with the physical properties of the microenvironment and transmit the signals to activate the cytoskeletal movements may help identify an effective strategy for the treatment of cancer. Here, we will discuss the role of tumor microenvironment during cancer metastasis and how physical forces remodel the cytoskeleton through mechanosensing and transduction.

Ion Channel Regulation by Sex Steroid Hormones and Vitamin D in Cancer: A Potential Opportunity for Cancer Diagnosis and Therapy

Many ion channels are involved in tumor development, promoting cancer cell proliferation, migration, invasion, and survival. Accordingly, some of them have been suggested as tumor markers and novel targets for cancer therapy. Some sex steroid hormones (SSH), including estrogens and androgens, favor cancer progression. Meanwhile, other steroid hormones like vitamin D may have anticancer properties. SSH and vitamin D modulate the expression of a number of ion channels in cancer cells from hormone-sensitive tissues, including breast, ovary, prostate, and cervix. Moreover, rapid effects of SSH may be mediated by their direct action on membrane ion channels. Here, we reviewed the SSH and vitamin D regulation of ion channels involved in cancer, and analyzed the potential molecular pathways implicated. In addition, we described the potential clinical use of ion channels in cancer diagnosis and therapy, taking advantage of their regulation by SSH and vitamin D. Since SSH are considered risk factors for different types of cancer, and ion channels play important roles in tumor progression, the regulation of ion channels by SSH and vitamin D may represent a potential opportunity for early cancer diagnosis and therapeutic approaches in SSH and vitamin D sensitive tumors.

Expression and Role of the G Protein-Coupled Estrogen Receptor (GPR30/GPER) in the Development and Immune Response in Female Reproductive Cancers

Cancer is a major public health issue and represents the second leading cause of death in women worldwide, as female reproductive-related neoplasms are the main cause of incidence and mortality. Female reproductive cancers have a close relationship to estrogens, the principal female sex steroid hormones. Estrogens exert their actions by the nuclear estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). ERα, and ERβ act as transcription factors mediating genomic effects. Besides, the G protein-coupled estrogen receptor (GPER, formerly known as GPR30) was recently described as a seven-transmembrane receptor that mediates non-genomic estrogenic signaling, including calcium mobilization, cAMP synthesis, cleavage of matrix metalloproteinases, transactivation of epidermal growth factor receptor (EGFR), and the subsequent activation of PI3K and MAPK signaling pathways, which are the reasons why it is related to cellular processes, such as cell-cycle progression, cellular proliferation, differentiation, apoptosis, migration, and invasion. Since its discovery, selective agonists and antagonists have been found and developed. GPER has been implicated in a variety of hormone-responsiveness tumors, such as breast, endometrial, ovarian, cervical, prostate, and testicular cancer as well as lung, hepatic, thyroid, colorectal, and adrenocortical cancers. Nevertheless, GPER actions in cancer are still debatable due to the conflicting information that has been reported to date, since many reports indicate that activation of this receptor can modulate carcinogenesis. In contrast, many others show that its activation inhibits tumor activity. Besides, estrogens play an essential role in the regulation of the immune system, but little information exists about the role of GPER activation on its modulation within cancer context. This review focuses on the role that the stimulation of GPER plays in female reproductive neoplasms, specifically breast, endometrial, ovarian, and cervical cancers, in its tumor activity and immune response regulation.

The voltage-gated sodium channel Nav1.7 associated with endometrial cancer

Background: Endometrial cancer is the most common gynecologic malignancy in women in the developed countries. Despite recent progress in functional characterization of voltage-gated sodium channel (Na_v) in multiple cancers, very little was known about the expression of Na_v in human endometrial cancer. The present study sought to determine the role of Na_v and molecular nature of this channel in the endometrial cancer.

Methods: PCR approach was introduced to determine expression level of Na_v subunits in endometrial cancer specimens. Pharmacological agents were used to investigate Na_v function in endometrial cancer cells. Flow cytometry were used to test cancer apoptosis, and invasion assays were applied to test tumor metastasis.

Results: Transcriptional levels of the all Na_v α and β subunits were determined by real time-PCR in endometrial cancer with pair tissues of carcinoma and adjacent nonneoplastic tissue, Na_v1.7 was the most highly expressed Na_v subtype in endometrial cancer tissues. Na_v1.7 level was closely associated with tumor size, local lymph node metastasis, and 5-year and 10-year survival ratio. Inhibition of this channel by Na_v1.7 blocker PF-05089771, promoted cancer apoptosis and attenuated cancer cell invasion.

Conclusion: These results establish a relationship between voltage-gated sodium channel protein and endometrial cancer, and suggest that Na_v1.7 is a potential prognostic biomarker and could serve as a novel therapeutic target for endometrial cancer.

G protein-coupled estrogen receptor in colon function, immune regulation and carcinogenesis

Estrogens play important roles in the development and progression of multiple tumor types. Accumulating evidence points to the significance of estrogen action not only in tumors of hormonally regulated tissues such as the breast, endometrium and ovary, but also in the development of colorectal cancer (CRC). The effects of estrogens in physiological and pathophysiological conditions are mediated by the nuclear estrogen receptors α and β, as well as the membrane-bound G protein-coupled estrogen receptor (GPER). The roles of GPER in CRC development and progression, however, remain poorly understood. Studies on the functions of GPER in the colon have shown that this estrogen receptor regulates colonic motility as well as immune responses in CRC-associated diseases, such as Crohn’s disease and ulcerative colitis. GPER is also involved in cell cycle regulation, endoplasmic reticulum stress, proliferation, apoptosis, vascularization, cell migration, and the regulation of fatty acid and estrogen metabolism in CRC cells. Thus, multiple lines of evidence suggest that GPER may play an important role in colorectal carcinogenesis. In this review, we present the current state of knowledge regarding the contribution of GPER to colon function and CRC.

The Role of Metabolic Syndrome in Endometrial Cancer: A Review

Endometrial cancer is one of the most common cancers of the female reproductive system. Although surgery, radiotherapy, chemotherapy, and hormone therapy can significantly improve the survival of patients, the treatment of patients with very early lesions and a strong desire to retain reproductive function or late recurrence is still in the early stages. Metabolic syndrome (MS) is a clustering of at least three of the five following medical conditions: central obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL). Obesity, diabetes and hypertension often coexist in patients with endometrial cancer, which increases the risk of endometrial cancer, also known as the "triple syndrome of endometrial cancer." In recent years, epidemiological and clinical studies have found that MS associated with metabolic diseases is closely related to the incidence of endometrial cancer. However, the key molecular mechanisms underlying the induction of endometrial cancer by MS have not been elucidated to date. Characterizing the tumor metabolism microenvironment will be advantageous for achieving a comprehensive view of the molecular mechanism of metabolic syndrome associated with endometrial cancer and for providing a new target for the treatment of endometrial cancer. This review focuses on recent advances in determining the role of metabolic syndrome-related factors and mechanisms in the pathogenesis of endometrial cancer. We suggest that interfering with the tumor metabolic microenvironment-related molecular signals may inhibit the occurrence of endometrial cancer.

Alterations in intracellular Ca2+ levels in human endometrial stromal cells after decidualization

Calcium (Ca²⁺) is an important element for many physiological functions of the uterus, including embryo implantation. Here, we investigated the possible involvement of altered intracellular Ca²⁺ levels in decidualization in human endometrial stromal cells (hEMSCs). hEMSCs showed high levels of mesenchymal stem cell marker expression (CD73, CD90, and CD105) and did not express markers of hematopoietic progenitor cells (CD31, CD34, CD45, and HLA-DR). Decidualization is a process of ovarian steroid-induced endometrial stromal cell proliferation and differentiation. Several types of ion channels, which are regulated by the ovarian hormones progesterone and estradiol, as well as growth factors, are important for endometrial receptivity and embryo implantation. The combined application of progesterone (1 μM medroxyprogesterone acetate) and cyclic AMP (0.5 mM) for 6 days not only elevated inositol 1,4,5-triphosphate receptor (IP₃R)-mediated Ca²⁺ release and IP₃R expression, it also promoted ORAI and STIM expression as well as cyclopiazonic acid-induced Ca²⁺ release. Finally, intracellular Ca²⁺ levels and ion channel gene expression influenced hEMSC proliferation. These results suggest that cytosolic Ca²⁺ dynamics, mediated by specific ion channels, serve as an important step in the decidualization of hEMSCs.

Anti-Cancer Agents in Proliferation and Cell Death: The Calcium Connection

Calcium (Ca2+) signaling and the modulation of intracellular calcium ([Ca2+]i) levels play critical roles in several key processes that regulate cellular survival, growth, differentiation, metabolism, and death in normal cells. On the other hand, aberrant Ca2+-signaling and loss of [Ca2+]i homeostasis contributes to tumor initiation proliferation, angiogenesis, and other key processes that support tumor progression in several different cancers. Currently, chemically and functionally distinct drugs are used as chemotherapeutic agents in the treatment and management of cancer among which certain anti-cancer drugs reportedly suppress pro-survival signals and activate pro-apoptotic signaling through modulation of Ca2+-signaling-dependent mechanisms. Most importantly, the modulation of [Ca2+]i levels via the endoplasmic reticulum-mitochondrial axis and corresponding action of channels and pumps within the plasma membrane play an important role in the survival and death of cancer cells. The endoplasmic reticulum-mitochondrial axis is of prime importance when considering Ca2+-signaling-dependent anti-cancer drug targets. This review discusses how calcium signaling is targeted by anti-cancer drugs and highlights the role of calcium signaling in epigenetic modification and the Warburg effect in tumorigenesis.

Clinical value screening, prognostic significance and key pathway identification of miR-204-5p in endometrial carcinoma: A study based on the Cancer Genome Atlas (TCGA), and bioinformatics analysis

BACKGROUND

Endometrial carcinoma is one of the common carcinomas in the female reproductive system. It is reported that miR-204-5p is down-regulated in endometrial carcinoma. However, the mechanism and key pathways of miR-204-5p in endometrial carcinoma have not been clarified.

MATERIAL/METHODS

We evaluated the expression profiles and prognostic value of miR-204-5p expression in endometrial carcinoma by using bioinformatics analysis of a public dataset from TCGA. Drug of endometrial carcinoma from DrugBank, GO analysis, KEGG analysis, PPI network, mutation, as well as assessment of the prognostic significance were performed to the overlapping target genes of miR-204-5p in endometrial carcinoma. The relative expression levels of miR-204-5p target genes in endometrial carcinoma, including SF3B1, FBXW7, SPOP, and BRD4, were assessed by real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

First, through DrugBank website, we obtained target drugs for endometrial carcinoma. MiR-204-5p expression was found to be lower in the endometrial carcinoma tissues than in adjacent normal tissues from TCGA. Next, we identified 143 genes as potential targets of miR-204-5p. Then, through GO enrichment analysis, KEGG signaling pathway and PPI analysis, we revealed the key networks in endometrial carcinoma. Next, mutation and assessment of the prognostic significance of endometrial carcinoma were obtained. At last, in endometrial carcinoma, the relative expression of SF3B1 and BRD4 increased, and the relative expression of FBXW7 decreased.

CONCLUSIONS

MiR-204-5p is down-regulated in endometrial carcinoma and affects the prognostic significance of endometrial carcinoma, which might play an important role in the tumorigenesis of endometrial carcinoma.

Estrogen Enhances Endometrial Cancer Cells Proliferation by Upregulation of Prohibitin

Estrogen plays an essential role in type I endometrial cancer cell proliferation. Despite great progresses in the etiology has been obtained in the past, however, the molecular mechanisms remain to be fully clarified. Prohibitin has been demonstrated involvement in multiple cancers' development. If it also contributes to estrogen-driven endometrial cancer proliferation is not clear. IHC assay result display that prohibitin overexpressed in endometrial cancer tissue and associated with the poor prognosis; Western blot assay detect that upregulated prohibitin expression with dose- and time-dependent manners. The cellular growth was monitored with SRB assay which demonstrate that knockdown prohibitin attenuated estrogen-induced proliferation. Ubiquitination assay finds estrogen increased prohibitin level through stabilizing prohibitin protein via inhibition of ubiquitination, while estrogen-induced protein expression was mediated by estrogen receptor. Our findings provide a new insight on the mechanism of estrogen-induced proliferation, implying the possibility of using prohibitin as a potential therapeutic target for the treatment of endometrial cancer.

An elevated preoperative serum calcium level is a significant predictor for positive peritoneal cytology in endometrial carcinoma

Objective

To evaluate preoperative serum calcium concentration and investigate the association between calcium level and positive peritoneal cytology in endometrial carcinoma (EC).

Methods

A total of 510 patients who were diagnosed with EC and had surgery were initially enrolled in this study at Peking University People’s Hospital between January 2012 and December 2016. Clinical characteristics and preoperative serum calcium, albumin, carbohydrate antigen (CA)125, CA19-9, carcinoembryonic antigen (CEA) were extracted from patient records and evaluated according to postoperative peritoneal cytology. Predictive factors were assessed with Cox univariate and multivariate analyses. Factors selected from multivariate analysis results were used to build a predictive model.

Results

A total of 510 patients are identified in our database and 444 patients who fulfilled inclusion and exclusion criteria are included in this study. Univariate analysis revealed that ionized calcium concentration was closely related to positive peritoneal cytology, tumor grade and lymph-vascular space invasion (LVSI). Moreover, peritoneal cytology was significantly associated with hypertension, tubal ligation, serum CA125, CA19-9, CEA and ionized calcium level. Multivariate analysis revealed that albumin-adjusted calcium level, CA125 and tubal ligation were independent predictive factors of positive peritoneal cytology (P<0.05). A combination of ionized calcium level with the other two indexes yielded significantly great area under the curve (AUC=0.824).

Conclusions

This study enhanced the value of preoperative ionized calcium level. We also identified several potential biomarkers to predict positive peritoneal cytology in EC patients before surgery.

Serum calcium is a novel parameter to assess metabolic syndrome in endometrial carcinoma

OBJECTIVES

To investigate the distribution of serum calcium and the relationship between serum calcium and serum metabolic parameters in endometrial carcinoma (EC) patients.

METHODS

Retrospective assessment of patients diagnosed with endometrial cancer from Peking University People's Hospital from 2004 to 2009. Clinical characteristics as well as pretreatment serum calcium, albumin, fasting plasma glucose (FPG), serum triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol (TC) value were extracted from patient records. Serum calcium was corrected for albumin. Unpaired t test and analysis of covariance were used to compare serum calcium among categorical variables. Simple correlation analyses and partial correlation analyses were used to assess the associations between serum calcium and continuous variables.

RESULTS

Two-hundred twenty patients were included in this study. After adjusting for confounders, postmenopausal patients had higher total serum calcium (p=0.002) and albumin-corrected serum calcium (p=0.012) than premenopausal patients, endometrioid endometrial carcinoma (EEC) patients had higher total serum calcium than non-endometrioid endometrial carcinoma (NEEC) patients (p=0.037). Significant positive correlations were found between total serum calcium and FPG (p=0.017), TG (p=0.043), HDL (p=0.042), LDL (p<0.001), and TC (p<0.001) after adjusting for multiple variables, and the corrected serum calcium showed no significant correlation with metabolic parameters.

CONCLUSION

Total serum calcium might be a more sensitive parameter for metabolic syndrome in endometrioid endometrial cancer patients than lipids.

Communication between genomic and non-genomic signaling events coordinate steroid hormone actions

Steroid hormones are lipophilic molecules produced in one cell that can travel great distances within the body to elicit biological effects in another cell. In the canonical pathway, steroid hormone binding to a nuclear receptor (NR), often in the cytoplasm, causes the receptor to undergo a conformational change and translocate to the nucleus, where it interacts with specific sequences of DNA to regulate transcription. In addition to the classical genomic mechanism of action, alternate mechanisms of steroid activity have emerged that involve rapid, non-genomic signaling. The distinction between these two major mechanisms of action lies in the subcellular location of the initiating steroid hormone action. Importantly, the mechanisms of action are not exclusive, in that each can affect the activity of the other. Here, we describe the different types of genomic and non-genomic steroid hormone signaling mechanisms and how they can influence one another to ultimately regulate biology. Further, we discuss the approaches being used to study the non-genomic signaling events and address important caveats to be considered when designing new experiments. Thus, this minireview can serve as an introduction to the diverse signaling mechanisms of steroid hormones and offers initial, experimental guidance to those entering the field.

LINC01016 promotes the malignant phenotype of endometrial cancer cells by regulating the miR-302a-3p/miR-3130-3p/NFYA/SATB1 axis

Long noncoding RNAs (lncRNAs) have been implicated in tumorigenesis and cancer progression and are tightly associated with the phenotypes of numerous cancers. However, the functional roles underlying these effects are unknown. The expression levels of LINC01016, miR-302a-3p, miR-3130-3p, NFYA, and SATB1 were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) in 33 endometrial cancer tissues and 20 normal tissues. Bioinformatics analyses, luciferase reporter analyses, chromatin immunoprecipitation (ChIP) assays, and qRT-PCR assays were performed to verify potential binding sites. The qRT-PCR and western blot were used to identify the regulatory mechanisms of LINC01016 in cell biological behavior, which were also examined by cell counting kit -8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EdU) assays, flow cytometry, wound healing assays, and transwell assays. LINC01016 was substantially upregulated in endometrial cancer tissues, and LINC01016 silencing abolished the malignant behavior of endometrial cancer cells. LINC01016 positively rescued the downstream gene nuclear factor YA (NFYA) by competitively “sponging” miR-302a-3p and miR-3130-3p. In turn, these two miRNAs could inhibit LINC01016 transcription, thus forming two reciprocal repression cycles, which influenced the biological behavior of endometrial cancer cells. MiR-302a-3p and miR-3130-3p could specifically bind with the 3′-UTR regions of NFYA, and NFYA could upregulate the expression of special AT-rich sequence-binding protein 1 (SATB1) as a transcriptional factor. This study was the first to show that the LINC01016–miR-302a-3p/miR-3130-3p/NFYA/SATB1 axis played a crucial role in the occurrence of endometrial cancer. These findings may provide relevant insights into the diagnosis and therapy of endometrial cancer.

NHERF1, a novel GPER associated protein, increases stability and activation of GPER in ER-positive breast cancer

G protein-coupled estrogen receptor (GPER) plays an important role in mediating the effects of estradiol. High levels of GPER have been implicated to associate with the malignant progress of invasive breast cancer (IBC). However, the mechanisms by which GPER protein levels were regulated remain unclear. In this study, PDZ protein Na+/H+ exchanger regulatory factor (NHERF1) was found to interact with GPER in breast cancer cells. This interaction was mediated by the PDZ2 domain of NHERF1 and the carboxyl terminal PDZ binding motif of GPER. NHERF1 was demonstrated to facilitate GPER expression at post-transcriptional level and improve GPER protein stability by inhibiting the receptor degradation via ubiquitin-proteasome pathway in a GPER/NHERF1 interaction-dependent manner. In addition, GPER protein levels are positively associated with NHERF1 protein levels in a panel of estrogen receptor (ER)-positive breast cancer cells. Furthermore, analysis of clinical IBC data from The Cancer Genome Atlas (TCGA) showed no significant difference in GPER mRNA levels between ER-positive IBC and normal breast tissues. However, gene set enrichment analysis (GSEA) showed that GPER signaling is ultra-activated in ER-positive IBC when compared with normal and its activation is positively associated with NHERF1 mRNA levels. Taken together, our findings identify NHERF1 as a new binding partner for GPER and its overexpression promotes protein stability and activation of GPER in ER-positive IBC. Our data indicate that regulation of GPER stability by NHERF1 may contribute to GPER-mediated carcinogenesis in ER-positive IBC.

Estrogen Activation by Steroid Sulfatase Increases Colorectal Cancer Proliferation via GPER

CONTEXT

Estrogens affect the incidence and progression of colorectal cancer (CRC), although the precise molecular mechanisms remain ill-defined.

OBJECTIVE

The present study investigated prereceptor estrogen metabolism through steroid sulphatase (STS) and 17β-hydroxysteroid dehydrogenase activity and subsequent nongenomic estrogen signaling in human CRC tissue, in The Cancer Genome Atlas colon adenocarcinoma data set, and in in vitro and in vivo CRC models. We aimed to define and therapeutically target pathways through which estrogens alter CRC proliferation and progression.

DESIGN, SETTING, PATIENTS, AND INTERVENTIONS

Human CRC samples with normal tissue-matched controls were collected from postmenopausal female and age-matched male patients. Estrogen metabolism enzymes and nongenomic downstream signaling pathways were determined. CRC cell lines were transfected with STS and cultured for in vitro and in vivo analysis. Estrogen metabolism was determined using an ultra-performance liquid chromatography-tandem mass spectrometry method.

PRIMARY OUTCOME MEASURE

The proliferative effects of estrogen metabolism were evaluated using 5-bromo-2'-deoxyuridine assays and CRC mouse xenograft studies.

RESULTS

Human CRC exhibits dysregulated estrogen metabolism, favoring estradiol synthesis. The activity of STS, the fundamental enzyme that activates conjugated estrogens, is significantly (P < 0.001) elevated in human CRC compared with matched controls. STS overexpression accelerates CRC proliferation in in vitro and in vivo models, with STS inhibition an effective treatment. We defined a G-protein-coupled estrogen receptor (GPER) proproliferative pathway potentially through increased expression of connective tissue growth factor in CRC.

CONCLUSION

Human CRC favors estradiol synthesis to augment proliferation via GPER stimulation. Further research is required regarding whether estrogen replacement therapy should be used with caution in patients at high risk of developing CRC.

Ca2+ protein alpha 1D of CaV1.3 regulates intracellular calcium concentration and migration of colon cancer cells through a non-canonical activity

It is generally accepted that voltage-gated Ca²⁺ channels, CaV, regulate Ca²⁺ homeostasis in excitable cells following plasma membrane depolarization. Here, we show that the Ca²⁺ protein α1D of CaV1.3 channel is overexpressed in colorectal cancer biopsies compared to normal tissues. Gene silencing experiments targeting α1D reduced the migration and the basal cytosolic Ca²⁺ concentration of HCT116 colon cancer cell line and modified the cytosolic Ca²⁺ oscillations induced by the sodium/calcium exchanger NCX1/3 working in its reverse mode. Interestingly, NCX1/3 regulated membrane potential of HCT116 cells only when α1D was silenced, and blocking NCX1/3 increased cytosolic Ca²⁺ concentration and cell migration. However, membrane depolarization did not induce an increase in intracellular Ca²⁺. Patch-clamp experiments clearly showed that the inward Ca²⁺ current was absent. Finally, flow cytometry and immunofluorescence studies showed that α1D protein was localized at the plasma membrane, in cytosol and cell nuclei. Altogether, we uncover a novel signaling pathway showing that α1D is involved in the regulation of Ca²⁺ homeostasis and cell migration by a mechanism independent of its plasma membrane canonical function but that involved plasma membrane Na⁺/Ca²⁺ exchanger.

Molecular mechanisms of tumour invasion: regulation by calcium signals

Intracellular calcium (Ca²⁺ ) signals are key regulators of multiple cellular functions, both healthy and physiopathological. It is therefore unsurprising that several cancers present a strong Ca²⁺ homeostasis deregulation. Among the various hallmarks of cancer disease, a particular role is played by metastasis, which has a critical impact on cancer patients' outcome. Importantly, Ca²⁺ signalling has been reported to control multiple aspects of the adaptive metastatic cancer cell behaviour, including epithelial-mesenchymal transition, cell migration, local invasion and induction of angiogenesis (see Abstract Figure). In this context Ca²⁺ signalling is considered to be a substantial intracellular tool that regulates the dynamicity and complexity of the metastatic cascade. In the present study we review the spatial and temporal organization of Ca²⁺ fluxes, as well as the molecular mechanisms involved in metastasis, analysing the key steps which regulate initial tumour spread.

ASIC1a mediates the drug resistance of human hepatocellular carcinoma via the Ca2+/PI3-kinase/AKT signaling pathway

Chemotherapy is the main treatment method of patients with advanced liver cancer. However, drug resistance is a serious problem in the treatment of hepatocellular carcinoma (HCC). Acid sensing ion channel 1a (ASIC1a) is a H⁺-gated cation channel; it mediates tumor cell migration and invasion, which suggests that it is involved in the development of malignant tumors. Therefore, we studied the relationship between ASIC1a and drug resistance in human hepatocellular carcinoma. In our study, we found that ASIC1a is highly expressed in human HCC tissue, and that its levels were significantly increased in resistant HCC cells Bel7402/FU and HepG2/ADM. Inhibiting the activity of ASIC1a enhances the chemosensitivity of Bel7402/FU and HepG2/ADM cells. The overexpression of ASIC1a contributed to drug resistance in Bel7402 and HepG2 cells, whereas knockdown of ASIC1a overcame drug resistance in Bel7402/FU and HepG2/ADM cells. We further demonstrated that ASIC1a mediated calcium influx, which resulted in the activation of PI3K/AKT signaling and increased drug resistance. These data suggest that ASIC1a/Ca²⁺/PI3K/AKT signaling represents a novel pathway that regulates drug resistance, thus offering a potential target for chemotherapy of HCC.

In vitro profiling of toxicity and endocrine disrupting effects of bisphenol analogues by employing MCF-7 cells and two-hybrid yeast bioassay

The potentially adverse health implications of bisphenol A (BPA) have led to increasing use of alternative bisphenols (BPs). However, little is known about the toxicity of alternative BPs. In this study, the cytotoxicity, genotoxicity, intracellular ROS formation, and Ca²⁺ fluctuation effects of BPs on MCF-7 cells were evaluated. At the same time, the estrogenic and thyroidal hormone effect potentials of six BPs were also evaluated using two-hybrid yeast bioassay. The results showed that most BPs at 0.01-1 μM significantly increased cell viability in MCF-7 cells and at higher exposure concentrations of 25-100 μM, they caused a significant decrease of cell viability. At the same time, these BPs also at 25-100 μM significantly increased LDH release of MCF-7 cells. In addition, several BPs at 10-50 μM resulted in a significantly concentration-depended increase in DNA-damaging effect on MCF-7 cells and elevated ROS production. Most BPs at 0.0001-10 μM significantly increased intracellular Ca²⁺ level. These results showed that bisphenol AF (BPAF) and thiodiphenol (TDP) exerted cell biological effect, estrogenic, and thyroidal effect potentials greater than those of BPA. The cytotoxicity and endocrine disrupting effects of other BPs are similar to or slightly lower than those of BPA. Therefore, as potential alternatives to BPA, endocrine disrupting effects and potential health harm of alternative BPs to human can also not be ignored. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 278-289, 2017.

L-type calcium channels regulate filopodia stability and cancer cell invasion downstream of integrin signalling

Mounting in vitro, in vivo and clinical evidence suggest an important role for filopodia in driving cancer cell invasion. Using a high-throughput microscopic-based drug screen, we identify FDA-approved calcium channel blockers (CCBs) as potent inhibitors of filopodia formation in cancer cells. Unexpectedly, we discover that L-type calcium channels are functional and frequently expressed in cancer cells suggesting a previously unappreciated role for these channels during tumorigenesis. We further demonstrate that, at filopodia, L-type calcium channels are activated by integrin inside-out signalling, integrin activation and Src. Moreover, L-type calcium channels promote filopodia stability and maturation into talin-rich adhesions through the spatially restricted regulation of calcium entry and subsequent activation of the protease calpain-1. Altogether we uncover a novel and clinically relevant signalling pathway that regulates filopodia formation in cancer cells and propose that cycles of filopodia stabilization, followed by maturation into focal adhesions, directs cancer cell migration and invasion.

Filopodia have a prominent role in driving cancer cell invasion. Here, the authors show that L-type calcium channels are a druggable target regulating filopodia stability and maturation into focal adhesions in metastatic breast cancer cells.

Plasma membrane ion channels and epithelial to mesenchymal transition in cancer cells

A variety of studies have suggested that epithelial to mesenchymal transition (EMT) may be important in the progression of cancer in patients through metastasis and/or therapeutic resistance. A number of pathways have been investigated in EMT in cancer cells. Recently, changes in plasma membrane ion channel expression as a consequence of EMT have been reported. Other studies have identified specific ion channels able to regulate aspects of EMT induction. The utility of plasma membrane ion channels as targets for pharmacological modulation make them attractive for therapeutic approaches to target EMT. In this review, we provide an overview of some of the key plasma membrane ion channel types and highlight some of the studies that are beginning to define changes in plasma membrane ion channels as a consequence of EMT and also their possible roles in EMT induction.

Genetics of primary hyperaldosteronism

Hypertension is a common medical condition and affects approximately 20% of the population in developed countries. Primary aldosteronism is the most common form of secondary hypertension and affects 8-13% of patients with hypertension. The two most common causes of primary aldosteronism are aldosterone-producing adenoma and bilateral adrenal hyperplasia. Familial hyperaldosteronism types I, II and III are the known genetic syndromes, in which both adrenal glands produce excessive amounts of aldosterone. However, only a minority of patients with primary aldosteronism have one of these syndromes. Several novel susceptibility genes have been found to be mutated in aldosterone-producing adenomas: KCNJ5, ATP1A1, ATP2B3, CTNNB1, CACNA1D, CACNA1H and ARMC5 This review describes the genes currently known to be responsible for primary aldosteronism, discusses the origin of aldosterone-producing adenomas and considers the future clinical implications based on these novel insights.

Ultrasound-targeted microbubble destruction of calcium channel subunit α 1D siRNA inhibits breast cancer via G protein-coupled receptor 30

Estrogen has been closely associated with breast cancer. Several studies reported that Ca²⁺ signal and Ca²⁺ channels act in estrogen-modulated non-genomic pathway of breast cancer, however little was revealed on the function of L-type Ca²⁺ channels. The L-type Ca²⁺ channel subunit α 1D, named Cav1.3 was found in breast cancer cells. We aimed to investigate the expression and activity of Cav1.3 in human breast cancer, and reveal the effect of estrogen in regulating the expression of Cav1.3. The qRT-PCR and western blotting were employed to show that Cav1.3 was highly expressed in breast cancer tissues. E2 exposure rapidly upregulated the expression of Cav1.3 in dosage- and time-dependent manner, and promoted Ca²⁺ influx. The silencing of G protein-coupled estrogen receptor 30 (GPER1/GPR30) using siRNA transfection inhibited the upregulation of Cav1.3 and Ca²⁺ influx induced by E2. Moreover, the inhibition of Cav1.3 by siRNA transfection suppressed E2-induced second peak of Ca²⁺ signal, the expression of p-ERK1/2, and the cell proliferation. Ultrasound-targeted microbubble destruction (UTMD) of Cav1.3 siRNA was used in MCF-7 cells in vitro and in the tumor xenografts mice in vivo. The application of UTMD significantly suppressed the tumor growth and promoted the survival rate. In conclusion, E2 upregulated the expression of Cav1.3 for Ca²⁺ influx to promote the expression of p-ERK1/2 for cell proliferation. The study confirmed that the mechanism of E2 inducing the expression of Cav1.3 through a non-genomic pathway, and highlighted that UTMD of Cav1.3 siRNA is a powerful promising technology for breast cancer gene therapy.

Rapid estrogen actions on ion channels: A survey in search for mechanisms

A survey of nearly two hundred reports shows that rapid estrogenic actions can be detected across a range of kinds of estrogens, a range of doses, on a wide range of tissue, cell and ion channel types. Striking is the fact that preparations of estrogenic agents that do not permeate the cell membrane almost always mimic the actions of the estrogenic agents that do permeate the membrane. All kinds of estrogens, ranging from natural ones, through receptor modulators, endocrine disruptors, phytoestrogens, agonists, and antagonists to novel G-1 and STX, have been reported to be effective. For actions on specific types of ion channels, the possibility of opposing actions, in different cases, is the rule, not the exception. With this variety there is no single, specific action mechanism for estrogens per se, although in some cases estrogens can act directly or via some signaling pathways to affect ion channels. We infer that estrogens can bind a large number of substrates/receptors at the membrane surface. As against the variety of subsequent routes of action, this initial step of the estrogen's binding action is the key.