Participation of WNT and β-Catenin in Physiological and Pathological Endometrial Changes: Association with Angiogenesis

Melatonin and resveratrol alleviate molecular and metabolic toxicity induced by Bisphenol A in endometrial organoids

Bisphenol A (BPA), a widespread environmental contaminant, poses concerns due to its disruptive effects on physiological functions of the uterine endometrium. In contrast, melatonin (MT) and Resveratrol (RSV) are under scrutiny for their potential protective roles against BPA-induced damage. For the efficacy and ethical concerns in the animal test, endometrial organoids, three-dimensional models mimicking endometrium, serve as crucial tools for unraveling the impact of environmental factors on reproductive health. This study aimed to comprehensively characterize the morphological, molecular and metabolic responses of porcine endometrial organoids to BPA and assess the potential protective effects of MT and RSV. Porcine uteri were prepared, digested with collagenase, mixed with Matrigel, and incubated at 38°C with 5 % CO2. Passaging involved dissociation through trypsin-EDTA treatment and subculturing. The culture medium was refreshed every 2-3 days. To investigate the environmental impact on reproductive health, endometrial organoids were treated with BPA (0.5 µM), MT (with/without BPA at 0.1 µM), and/or RSV (10 µM). Various molecular screening using gene expression, western blotting, immunofluorescence staining, and metabolites profiling were assessed the effects of BPA, MT, and RSV in terms of cell viability, morphology, reproductivity, and metabolism alteration in the endometrial organoids. As expected, BPA induced structural and molecular disruptions in organoids, affecting cytoskeletal proteins, Wnt/β-catenin signaling, and epithelial/mesenchymal markers. It triggered oxidative stress and apoptotic pathways, altered miRNA expression, and disrupted the endocannabinoid system. The level of glucose, galactose, and essential amino acids were increased or decreased by approximately 1.5-3 times in BPA-treated groups compared to the control groups (p-value < 0.05), indicating metabolic changes. Moreover, MT and RSV treated groups exhibited protective effects, mitigating BPA-induced disruptions across multiple pathways. For the first time, our study models endometrial organoids, advancing understanding of environmental impacts on reproductive health.

The Effect of Selenium on Endometrial Repair in Goats with Endometritis at High Cortisol Levels

Endometritis is a common postpartum disease of female animals that causes significant losses to the goat industry. High levels of cortisol induced by various stresses after delivery severely inhibit innate immunity and tissue repair. The repair ability of the endometrium is closely related to the reproductive performance of goats. Selenium (Se) is an essential trace element in animals that has powerful antioxidant and immunity-enhancing functions. In this study, we established a goat model of endometritis at high cortisol (Hydrocortisone) levels to investigate the effect of Se (supplement additive) on endometrial repair. The results showed that the clinical symptoms, %PMN in uterine secretions, morphological endometrial damage, and the gene expression of BAX were reduced in the goats with Se supplementation compared with those in the model group. Se increased the gene expression of BCL2, VEGFA, TGFB1, and PCNA and activated the PI3K/AKT and Wnt/β-catenin signaling pathways in goats with Se supplementation. In conclusion, Se reduced the inflammatory response, increased the proliferation, and decreased the apoptosis of endometrial cells to promote endometrial tissue repair in goats with endometritis at high cortisol levels. It probably achieved this effect of promoting repair by activating the Wnt/β-catenin and PI3K/AKT pathways and affecting the gene expression of VEGFA, TGFB1, PCNA, BCL2, and BAX.

Association of Membranous WNT-1 and Nuclear mTOR with Endometrial Cancer Grade

Endometrial cancer remains a common cancer affecting the female reproductive system. There is still a need for more efficient ways of determining the degree of malignancy and optimizing treatment. WNT and mTOR are components of signaling pathways within tumor cells, and dysfunction of either protein is associated with the pathogenesis of neoplasms. Therefore, the aim of our study was to assess the impact of subcellular WNT-1 and mTOR levels on the clinical course of endometrial cancer. WNT-1 and mTOR levels in the plasma membrane, nucleus, and cytoplasm were evaluated using immunohistochemical staining in a group of 64 patients with endometrial cancer of grades 1-3 and FIGO stages I-IV. We discovered that the levels of WNT-1 and mTOR expression in the cellular compartments were associated with tumor grade and staging. Membranous WNT-1 was negatively associated, whereas cytoplasmic WNT-1 and nuclear mTOR were positively associated with higher grading of endometrial cancer. Furthermore, nuclear mTOR was positively associated with FIGO stages IB-IV. To conclude, we found that the assessment of WNT-1 in the cell membrane may be useful for exclusion of grade 3 neoplasms, whereas cytoplasmic WNT-1 and nuclear mTOR may be used as indicators for confirmation of grade 3 neoplasms.

STK4 protein expression pattern follows different trends in endometrioid and serous endometrial adenocarcinoma upon tumor progression

In a previous study, we showed that serine/threonine-protein kinase 4 (STK4) is involved in the control on proliferation and migration of endometrial cancer (EC) cells in vitro. In the present paper, we studied STK4 expression in EC tissues from a large cohort of patients to determine whether STK4 can serve as a marker for the aggressiveness and prognosis of EC. Tissue samples from patients with EC were examined for tumor type, grade, and stage. The STK4 protein expression in EC cells was assessed by immunohistochemistry and related to clinicopathological data of patients, such as progression and patient survival rate. The STK4 mRNA levels and its relation to the survival rate were analyzed also in publicly available databases. The STK4 gene expression was low at both, the mRNA and protein levels in EC, especially in serous tumors. Comparison of STK4 expression with the patient survival rate shows that the higher expression is associated with worse prognosis in serous EC, while no such dependence was found in endometrioid EC. Hence, the determination of the SKT4 expression pattern could be used as a putative prognostic marker for serous EC.

Single-cell transcriptomic analysis highlights origin and pathological process of human endometrioid endometrial carcinoma

Endometrial cancers are complex ecosystems composed of cells with distinct phenotypes, genotypes, and epigenetic states. Current models do not adequately reflect oncogenic origin and pathological progression in patients. Here we use single-cell RNA sequencing to profile cells from normal endometrium, atypical endometrial hyperplasia, and endometrioid endometrial cancer (EEC), which altogether represent the step-by-step development of endometrial cancer. We find that EEC originates from endometrial epithelial cells but not stromal cells, and unciliated glandular epithelium is the source of EEC. We also identify LCN2 + /SAA1/2 + cells as a featured subpopulation of endometrial tumorigenesis. Finally, the stromal niche and immune environment changes during EEC progression are described. This study elucidates the evolution of cell populations in EEC development at single-cell resolution, which would provide a direction to facilitate EEC research and diagnosis.

Transient and Prolonged Activation of Wnt Signaling Contribute Oppositely to the Pathogenesis of Asherman's Syndrome

Asherman’s Syndrome (AS) is caused by dysfunction of endometrial regenerative ability, which is controlled by adult stem cells and their niche. The Wnt signaling pathway has been demonstrated to be implicated in this process. This study aimed to clarify the relationship between the Wnt signaling pathway and the progression of AS after initial endometrial damage. Endometria with and without adhesion as well as from the intrauterine devices three months after the surgery were collected to compare the area of fibrosis. The area% of fibrosis did not vary significantly. Significantly higher expression of non-phosphorylated β-catenin, Wnt5a and Wnt7a was identified in the endometria with adhesion. The CD140b⁺CD146⁺ endometrial stem-like cells were present in the endometria with adhesion. Both Wnt5a and Wnt7a promoted stem cell proliferation. However, only Wnt7a preserved stem cell population by stimulating self-renewal. A rat endometrial injury model was established to investigate the effect of the activated Wnt/β-catenin signaling pathway on endometrial healing. We found that a transient activation of the Wnt/β-catenin signaling pathway promoted angiogenesis and increased the number of glands. In conclusion, transient activation of the Wnt/β-catenin signaling pathway during the acute endometrial damage may help the tissue regeneration, while prolonged activation may correlate to fibrosis formation.

Proteomic Analysis of Chicken Chorioallantoic Membrane (CAM) during Embryonic Development Provides Functional Insight

In oviparous animals, the egg contains all resources required for embryonic development. The chorioallantoic membrane (CAM) is a placenta-like structure produced by the embryo for acid-base balance, respiration, and calcium solubilization from the eggshell for bone mineralization. The CAM is a valuable in vivo model in cancer research for development of drug delivery systems and has been used to study tissue grafts, tumor metastasis, toxicology, angiogenesis, and assessment of bacterial invasion. However, the protein constituents involved in different CAM functions are poorly understood. Therefore, we have characterized the CAM proteome at two stages of development (ED12 and ED19) and assessed the contribution of the embryonic blood serum (EBS) proteome to identify CAM-unique proteins. LC/MS/MS-based proteomics allowed the identification of 1470, 1445, and 791 proteins in CAM (ED12), CAM (ED19), and EBS, respectively. In total, 1796 unique proteins were identified. Of these, 175 (ED12), 177 (ED19), and 105 (EBS) were specific to these stages/compartments. This study attributed specific CAM protein constituents to functions such as calcium ion transport, gas exchange, vasculature development, and chemical protection against invading pathogens. Defining the complex nature of the CAM proteome provides a crucial basis to expand its biomedical applications for pharmaceutical and cancer research.

The vaginal microbiome is associated with endometrial cancer grade and histology

The human microbiome has been strongly correlated with disease pathology and outcomes, yet remains relatively underexplored in patients with malignant endometrial disease. In this study, vaginal microbiome samples were prospectively collected at the time of hysterectomy from 61 racially and ethnically diverse patients from three disease conditions: 1) benign gynecologic disease (controls, n=11), 2) low-grade endometrial carcinoma (n=30), and 3) high-grade endometrial carcinoma (n=20). Extracted DNA underwent shotgun metagenomics sequencing, and microbial α and β diversities were calculated. Hierarchical clustering was used to describe community state types (CST), which were then compared by microbial diversity and grade. Differential abundance was calculated, and machine learning utilized to assess the predictive value of bacterial abundance to distinguish grade and histology. Both α- and β-diversity were associated with patient tumor grade. Four vaginal CST were identified that associated with grade of disease. Different histologies also demonstrated variation in CST within tumor grades. Using supervised clustering algorithms, critical microbiome markers at the species level were used to build models that predicted benign vs carcinoma, high-grade carcinoma versus benign, and high-grade versus low-grade carcinoma with high accuracy. These results confirm that the vaginal microbiome segregates not just benign disease from endometrial cancer, but is predictive of histology and grade. Further characterization of these findings in large, prospective studies is needed to elucidate their potential clinical applications.

High-Throughput In Vitro Screening Identified Nemadipine as a Novel Suppressor of Embryo Implantation

Current contraceptive methods interfere with folliculogenesis, fertilization, and embryo implantation by physical or hormonal approaches. Although hormonal contraceptive pills are effective in regulating egg formation, they are less effective in preventing embryo implantation. To explore the use of non-hormonal compounds that suppress embryo implantation, we established a high-throughput spheroid-endometrial epithelial cell co-culture assay to screen the Library of Pharmacologically Active Compounds (LOPAC) for compounds that affect trophoblastic spheroid (blastocyst surrogate) attachment onto endometrial epithelial Ishikawa cells. We identified 174 out of 1280 LOPAC that significantly suppressed BeWo spheroid attachment onto endometrial Ishikawa cells. Among the top 20 compounds, we found the one with the lowest cytotoxicity in Ishikawa cells, P11B5, which was later identified as Nemadipine-A. Nemadipine-A at 10 µM also suppressed BeWo spheroid attachment onto endometrial epithelial RL95-2 cells and primary human endometrial epithelial cells (hEECs) isolated from LH +7/8-day endometrial biopsies. Mice at 1.5 days post coitum (dpc) treated with a transcervical injection of 100 µg/kg Nemadipine-A or 500 µg/kg PRI-724 (control, Wnt-inhibitor), but not 10 µg/kg Nemadipine-A, suppressed embryo implantation compared with controls. The transcript expressions of endometrial receptivity markers, integrin αV (ITGAV) and mucin 1 (MUC1), but not β-catenin (CTNNB1), were significantly decreased at 2.5 dpc in the uterus of treated mice compared with controls. The reduction of embryo implantation by Nemadipine-A was likely mediated through suppressing endometrial receptivity molecules ITGAV and MUC1. Nemadipine-A is a potential novel non-hormonal compound for contraception.

Small Extracellular Vesicles Derived from Human Umbilical Cord Mesenchymal Stem Cells Enhanced Proangiogenic Potential of Cardiac Fibroblasts via Angiopoietin-Like 4

Background and Objectives. After myocardial hypoxic injury, it is important to enhance vascular formation and restore blood supply for injury repair. Previous studies have suggested that cardiac fibroblasts (CFs) play a crucial role in angiogenesis after myocardial injury. Small extracellular vesicles (sEVs) derived from human umbilical cord mesenchymal stem cells (hucMSCs) promote fibroblast-to-myofibroblast differentiation in inflammatory environment and have cardioprotective effects. It remains unknown whether sEVs regulate cardiac fibroblasts to promote angiogenesis after myocardial injury. Methods and Results. We isolated primary CFs from Sprague-Dawley rats (1–3 days old) and treated them with lipopolysaccharide (LPS) and LPS+sEVs. RNA sequencing analysis revealed that angiopoietin-like 4 (Angptl4) was increased in the LPS+sEVs group more than in the LPS group. After inhibition of Angptl4 expression in sEVs and CFs, cell proliferation, Transwell migration, and tube formation assays were used to detect the angiogenic activity of human umbilical vein endothelial cells. β-Catenin expression in CFs was detected by western blotting. The β-catenin inhibitor ICG001 was used to examine whether β-catenin was involved in the proangiogenic potential of CFs promoted by sEVs. sEVs enhanced the proangiogenic potential of CFs under inflammatory conditions, which was associated with β-catenin signaling. The proangiogenic potential of CFs was decreased when Angptl4 was knocked down in CFs and in hucMSCs. Conclusions. The sEVs regulated CFs to promote angiogenesis via Angptl4 in an inflammatory environment. This may provide a research basis for treating myocardial injury with sEVs.

CTEN Inhibits Tumor Angiogenesis and Growth by Targeting VEGFA Through Down-Regulation of β-Catenin in Breast Cancer

C-terminal tensin-like (CTEN) belongs to the tensin gene family, which encodes proteins that localize to focal adhesions and modulate integrin function. Accumulating studies have reported that CTEN expression can be upregulated or downregulated in different types of cancers, suggesting that CTEN has both oncogenic and tumor suppressor functions. In this study, by analyzing the expression level of CTEN in the human breast cancer (BRCA) samples from the clinically annotated genomic database, The Cancer Genome Atlas, we found that CTEN was downregulated in different BRCA subclasses, including luminal, human epidermal growth factor receptor 2 positive and triple-negative BRCA. Consistently, the protein level of CTEN was also reduced in BRCA based on the Proteomic Tumor Analysis Consortium. In contrast, vascular endothelial growth factor A (VEGFA), a signal protein that stimulates the formation of blood vessels, was upregulated in BRCA. CTEN overexpression in human umbilical vein endothelial cells and MCF7 significantly suppressed the expression of VEGFA, inhibited cell proliferation, migration, and tube formation in vitro. Mechanistically, CTEN bind to casitas B-lineage lymphoma (c-Cbl), an E3 ubiquitin-protein ligase, and decreased the β-catenin expression. In turn, the downregulation of β-catenin reduced the expression of VEGFA. Rescuing β-catenin expression effectively ameliorated the effect of CTEN overexpression in cell proliferation, migration, and tube formation. In conclusion, CTEN inhibited tumor angiogenesis by targeting VEGFA through c-Cbl-mediated down-regulation of β-catenin and may serve as a tumor suppressor in BRCA.

Targeting Wnt Signaling in Endometrial Cancer

Simple Summary

Wnt has diverse regulatory roles at multiple cellular levels and numerous targeting points, and aberrant Wnt signaling has crucial roles in carcinogenesis, metastasis, cancer recurrence, and chemotherapy resistance; based on these facts, Wnt represents an appealing therapeutic target for cancer treatment. Although preclinical data supports a role for the Wnt signaling pathway in uterine carcinogenesis, this area remains understudied. In this review, we identify the functions of several oncogenes of the Wnt/β-catenin signaling pathway in tumorigenesis and address the translation approach with potent Wnt inhibitors that have already been established or are being investigated to target key components of the pathway. Further research is likely to expand the potential for both biomarker and cancer drug development. There is a scarcity of treatment choices for advanced and recurrent endometrial cancer; investigating the sophisticated connections of Wnt signaling networks in endometrial cancer could address the unmet need for new therapeutic targets.

Abstract

This review presents new findings on Wnt signaling in endometrial carcinoma and implications for possible future treatments. The Wnt proteins are essential mediators in cell signaling during vertebrate embryo development. Recent biochemical and genetic studies have provided significant insight into Wnt signaling, in particular in cell cycle regulation, inflammation, and cancer. The role of Wnt signaling is well established in gastrointestinal and breast cancers, but its function in gynecologic cancers, especially in endometrial cancers, has not been well elucidated. Development of a subset of endometrial carcinomas has been attributed to activation of the APC/β-catenin signaling pathway (due to β-catenin mutations) and downregulation of Wnt antagonists by epigenetic silencing. The Wnt pathway also appears to be linked to estrogen and progesterone, and new findings implicate it in mTOR and Hedgehog signaling. Therapeutic interference of Wnt signaling remains a significant challenge. Herein, we discuss the Wnt-activating mechanisms in endometrial cancer and review the current advances and challenges in drug discovery.

In Vivo Targets of Pasteurella Multocida Toxin

Many Pasteurella multocida strains are carried as commensals, while some cause disease in animals and humans. Some type D strains cause atrophic rhinitis in pigs, where the causative agent is known to be the Pasteurella multocida toxin (PMT). PMT activates three families of G-proteins—G_q/11, G_12/13, and G_i/o—leading to cellular mitogenesis and other sequelae. The effects of PMT on whole animals in vivo have been investigated previously, but only at the level of organ-specific pathogenesis. We report here the first study to screen all the organs targeted by the toxin by using the QE antibody that recognizes only PMT-modified G-proteins. Under our experimental conditions, short-term treatment of PMT is shown to have multiple in vivo targets, demonstrating G-alpha protein modification, stimulation of proliferation markers and expression of active β-catenin in a tissue- and cell-specific manner. This highlights the usefulness of PMT as an important tool for dissecting the specific roles of different G-alpha proteins in vivo.

Controlled Ovarian Stimulation Protocols Alter Endometrial Histomorphology and Gene Expression Profiles

Although it is well appreciated that ovarian stimulation protocols for in vitro fertilization (IVF) alter endometrial receptivity, the precise cellular mechanisms are not known. To gain insights into potential mechanisms by which different ovarian stimulation protocols alter the endometrium, we compared histologic and gene expression profiles of endometrium from women undergoing conventional ovarian stimulation for IVF (C-IVF) with those undergoing minimal stimulation with clomiphene citrate (MS-IVF). Sixteen women undergoing MS-IVF (n = 8) or C-IVF (n = 8) were recruited for endometrial biopsy at the time of oocyte retrieval. Endometrial glands were large, tortuous, and secretory with C-IVF but small and undifferentiated with MS-IVF. Whereas RNA sequencing did not reveal changes in estrogen receptor or its co-regulators or classic proliferation associated genes in MS-IVF, together with immunohistochemistry, Wnt signaling was disrupted in endometrium from MS-IVF cycles with significant upregulation of Wnt inhibitors. Secreted frizzled-related protein 1 (sFRP1) was increased fourfold (p < 0.01), and sFRP4 was upregulated sixfold (p < 0.01) relative to C-IVF. Further these proteins were localized to subepithelial endometrial stroma. These data indicate that MS-IVF protocols with CC do not seem to impact endometrial estrogen signaling as much as would be expected from the reported antiestrogenic properties of CC. Rather, the findings of this study highlight Wnt signaling as a major factor for endometrial development during IVF cycles.

Crosstalk of estrogen receptors and Wnt/β-catenin signaling in endometrial cancer

PURPOSE

To investigate the interaction between Wnt/β-catenin and estrogen signaling pathways in endometrial cancer (EC).

METHODS

119 women were involved in this study, including 65 women with histologically confirmed EC and 54 healthy women as a control group. Serum protein levels of Dkk1 were measured using ELISA. Protein expression levels of Dkk1, β-catenin, ER-β isoforms (β1, β2, β5), and ER-α were tested in paraffin-embedded tissues using IHC. Gene expression levels of Dkk1, CTNNB, ESR1, and ESR2 were tested in fresh tumorous and normal endometrium tissues using RT-PCR.

RESULTS

EC patients had significantly higher serum levels of Dkk1 protein compared with healthy women. Dkk1 and β-catenin showed different expression pattern in tumor cells compared to it in normal cells at the protein level but not at the gene level. Protein expression levels of ERβ2 and ERα were significantly lower in tumor cells compared with tumor-adjacent normal cells. Increased protein expression levels of ERα were associated with favorable clinicopathological features and better overall survival rate (OS). Protein expression levels of ERα were correlated with protein expression levels of Dkk1 and cytoplasmic β-catenin. The association between ERα expression levels and OS was no more significant when tested in regard to Dkk1- and cytoplasmic β-catenin expression levels.

CONCLUSIONS

Our data demonstrated that Wnt/β-catenin and estrogen signaling systems are dysregulated in EC showing; for the first time, a potential crosstalk between certain components of these two pathways, which in turn has affected the specificity of these molecules in disease characteristics. Understanding the signaling networks in EC is crucial in designing clinical trials to evaluate the efficacy of molecular-targeted agents and providing more successful therapies in the future.

Expression of β-catenin in human trophoblast and its role in placenta accreta and placenta previa

OBJECTIVES

To investigate the expression of β-catenin in chorionic villi, and to explore its roles in placenta accreta and placenta previa.

METHODS

We compared β-catenin expression in the control group, placenta accreta group (lesion area and normal zones), and placenta previa group (placental central and placental edge zones) by immunohistochemistry, Western blotting, and RT-PCR techniques.

RESULTS

Compared with the normal group, the placenta accreta group had a longer length of stay, greater bleeding volume, and lower newborn birth weight. Further, the expression of β-catenin was lower in both placenta previa and placenta accreta groups than in the control group, as measured by immunohistochemistry. Compared with the control group, expression of β-catenin was significantly lower in the placenta previa and placenta accreta groups by Western blotting and RT-PCR. Importantly, the level of placental β-catenin was significantly different when compared between the lesion and normal zones of placenta.

CONCLUSION

The expression of β-catenin in placenta accreta might play an important role in the regulation of placental cell invasion; low expression of β-catenin in placenta accreta might be responsible for excessive trophoblastic invasion.

Inside the Endometrial Cell Signaling Subway: Mind the Gap(s)

Endometrial cells perceive and respond to their microenvironment forming the basis of endometrial homeostasis. Errors in endometrial cell signaling are responsible for a wide spectrum of endometrial pathologies ranging from infertility to cancer. Intensive research over the years has been decoding the sophisticated molecular means by which endometrial cells communicate to each other and with the embryo. The objective of this review is to provide the scientific community with the first overview of key endometrial cell signaling pathways operating throughout the menstrual cycle. On this basis, a comprehensive and critical assessment of the literature was performed to provide the tools for the authorship of this narrative review summarizing the pivotal components and signaling cascades operating during seven endometrial cell fate “routes”: proliferation, decidualization, implantation, migration, breakdown, regeneration, and angiogenesis. Albeit schematically presented as separate transit routes in a subway network and narrated in a distinct fashion, the majority of the time these routes overlap or occur simultaneously within endometrial cells. This review facilitates identification of novel trajectories of research in endometrial cellular communication and signaling. The meticulous study of endometrial signaling pathways potentiates both the discovery of novel therapeutic targets to tackle disease and vanguard fertility approaches.

Identification of differentially expressed placental transcripts during multiple gestations in the Eurasian beaver (Castor fiber L.)

The Eurasian beaver is one of the largest rodents that, despite its high impact on the environment, is a non-model species that lacks a reference genome. Characterising genes critical for pregnancy outcome can serve as a basis for identifying mechanisms underlying effective reproduction, which is required for the success of endangered species conservation programs. In the present study, high-throughput RNA sequencing (RNA-seq) was used to analyse global changes in the Castor fiber subplacenta transcriptome during multiple pregnancy. De novo reconstruction of the C. fiber subplacenta transcriptome was used to identify genes that were differentially expressed in placentas (n=5) from two females (in advanced twin and triple pregnancy). Analyses of the expression values revealed 124 contigs with significantly different expression; of these, 55 genes were identified using MegaBLAST. Within this group of differentially expressed genes (DEGs), 18 were upregulated and 37 were downregulated in twins. Most DEGs were associated with the following gene ontology terms: cellular process, single organism process, response to stimulus, metabolic process and biological regulation. Some genes were also assigned to the developmental process, the reproductive process or reproduction. Among this group, four genes (namely keratin 19 (Krt19) and wingless-type MMTV integration site family - member 2 (Wnt2), which were downregulated in twins, and Nik-related kinase (Nrk) and gap junction protein β2 (Gjb2), which were upregulated in twins) were assigned to placental development and nine (Krt19, Wnt2 and integrin α₇ (Itga7), downregulated in twins, and Nrk, gap junction protein β6 (Gjb6), GATA binding protein 6 (Gata6), apolipoprotein A-I (ApoA1), apolipoprotein B (ApoB) and haemoglobin subunit α₁ (HbA1), upregulated in twins) were assigned to embryo development. The results of the present study indicate that the number of fetuses affects the expression profile in the C. fiber subplacental transcriptome. Enhancement of transcriptomic resources for C. fiber will improve understanding of the pathways relevant to proper placental development and successful reproduction.

Oestrogen, progesterone and stem cells: the discordant trio in endometriosis?

Oestrogen–progesterone signalling is highly versatile and critical for the maintenance of healthy endometrium in humans. The genomic and nongenomic signalling cascades initiated by these hormones in differentiated cells of endometrium have been the primary focus of research since 1920s. However, last decade of research has shown a significant role of stem cells in the maintenance of a healthy endometrium and the modulatory effects of hormones on these cells. Endometriosis, the growth of endometrium outside the uterus, is very common in infertile patients and the elusiveness in understanding of disease pathology causes hindrance in selection of treatment approaches to enhance fertility. In endometriosis, the stem cells are dysfunctional as it can confer progesterone resistance to their progenies resulting in disharmony of hormonal orchestration of endometrial homeostasis. The bidirectional communication between stem cell signalling pathways and oestrogen–progesterone signalling is found to be disrupted in endometriosis though it is not clear which precedes the other. In this paper, we review the intricate connection between hormones, stem cells and the cross-talks in their signalling cascades in normal endometrium and discuss how this is deregulated in endometriosis. Re-examination of the oestrogen–progesterone dependency of endometrium with a focus on stem cells is imperative to delineate infertility associated with endometriosis and thereby aid in designing better treatment modalities.

Construction of a vascularized hydrogel for cardiac tissue formation in a porcine model

Replacing cardiac tissues lost to myocardial infarction remains a therapeutic goal for regenerative therapy in recovering cardiac function. We assessed the feasibility of constructing a macrosized human cardiac tissue construct using pluripotent stem cell-derived cardiomyocytes or control fibroblasts infused fibrin/collagen hydrogel and performed ectopic implantation in peripheral vascular system of a porcine model for 3 weeks. Finally, an optimized vascularized cardiac construct was explanted and grafted onto porcine myocardium for 2 weeks. Myocardial-grafted human cardiac constructs showed a nascent tissue-like organization with aligned cardiomyocytes within the remodelled collagen matrix. Nevertheless, no significant changes in intraconstruct density of cardiomyocytes were observed in the myocardial-grafted constructs (human embryonic stem cell [hESC]-derived cardiomyocyte [n = 4]: 70.5 ± 22.8 troponin I⁺ cardiomyocytes/high power field [HPF]) as compared to peripherally implanted constructs (hESC-derived cardiomyocyte [n = 4]: 59.0 ± 19.6 troponin I⁺ cardiomyocytes/HPF; human induced pluripotent stem cell-derived cardiomyocyte [n = 3]: 50.9 ± 8.5 troponin I⁺ cardiomyocytes/HPF, p = ns). However, the myocardial-grafted constructs showed an increased in neovascularization (194.4 ± 24.7 microvessels/mm² tissue, p < .05), microvascular maturation (82.8 ± 24.7 mature microvessels/mm² , p < .05), and tissue-like formation whereas the peripherally implanted constructs of hESC-derived cardiomyocyte (168.3 ± 98.2 microvessels/mm² tissue and 68.1 ± 33.4 mature microvessels/mm² ) and human induced pluripotent stem cell-derived cardiomyocyte (86.8 ± 57.4 microvessels/mm² tissue and 22.0 ± 32.7 mature microvessels/mm² ) were not significantly different in vascularized response when compared to the control human fibroblasts (n = 3) constructs (65.6 ± 34.1 microvessels/mm² tissue and 30.7 ± 20.7 mature microvessels/mm² ). We presented results on technical feasibility and challenges of grafting vascularized centimetre-sized human cardiac construct that may spur novel approaches in cardiac tissue replacement strategy.

IL-3R-alpha blockade inhibits tumor endothelial cell-derived extracellular vesicle (EV)-mediated vessel formation by targeting the β-catenin pathway

The proangiogenic cytokine Interleukin-3 (IL-3) is released by inflammatory cells in breast and ovarian cancer tissue microenvironments and also acts as an autocrine factor for human breast and kidney tumor-derived endothelial cells (TECs). We have previously shown that IL-3-treated endothelial cells (ECs) release extracellular vesicles (EVs), which serve as a paracrine mechanism for neighboring ECs, by transferring active molecules. The impact of an anti-IL-3R-alpha blocking antibody on the proangiogenic effect of EVs released from TECs (anti-IL-3R-EVs) has therefore been investigated in this study. We have found that anti-IL-3R-EV treatment prevented neovessel formation and, more importantly, also induced the regression of in vivo TEC-derived neovessels. Two miRs that target the canonical wingless (Wnt)/β-catenin pathway, at different levels, were found to be differentially regulated when comparing the miR-cargo of naive TEC-derived EVs (EVs) and anti-IL-3R-EVs. miR-214-3p, which directly targets β-catenin, was found to be upregulated, whereas miR-24-3p, which targets adenomatous polyposis coli (APC) and glycogen synthase kinase-3β (GSK3β), was found to be downregulated. In fact, upon their transfer into the cell, low β-catenin content and high levels of the two members of the “β-catenin destruction complex” were detected. Moreover, c-myc downregulation was found in TECs treated with anti-IL-3R-EVs, pre-miR-214-3p-EVs and antago-miR-24-3p-EVs, which is consistent with network analyses of miR-214-3p and miR-24-3p gene targeting. Finally, in vivo studies have demonstrated the impaired growth of vessels in pre-miR-214-3p-EV- and antago-miR-24-3p-EV-treated animals. These effects became much more evident when combo treatment was applied. The results of the present study identify the canonical Wnt/β-catenin pathway as a relevant mechanism of TEC-derived EV proangiogenic action. Furthermore, we herein provide evidence that IL-3R blockade may yield some significant advantages, than miR targeting, in inhibiting the proangiogenic effects of naive TEC-derived EVs by changing TEC-EV-miR cargo.

Mitochondrial ribosomal protein S18-2 is highly expressed in endometrial cancers along with free E2F1

Endometrial cancer (EC) is one of the most frequent causes of cancer death among women in developed countries. Histopathological diagnosis and imaging techniques for EC are limited, thus new prognostic markers are needed to offer patients the best treatment and follow-up.In the present paper we showed that the level of mitochondrial ribosomal protein MRPS18-2 (S18-2) increased in EC compared with the normal endometrium and hyperplasia, based on a study of 42 patient biopsies. Importantly, high expression of free E2F1 in EC correlates well with high S18-2 expression. The EC cell line HEC-1-A, which overexpresses S18-2 constitutively, showed an increased proliferation capacity in vitro and in vivo (in SCID mice). Moreover, pan-keratin, beta-catenin and E-cadherin signals are diminished in these cells, compared to the parental HEC-1-A line, in contrast to vimentin signal that is increased. This may be associated with epithelial-mesenchymal cell transition (EMT).We conclude that high expression of S18-2 and free E2F1, and low pan-keratin, beta-catenin, and E-cadherin signals might be a good set of prognostic markers for EC.

Analysis of differential genetic expression in endometrial polyps of postmenopausal women

OBJECTIVES

To evaluate the expression of four genetic markers (PTEN, BCL2, MLH1, and CTNNB1), linked to endometrial carcinogenesis, in endometrial polyps of patients with and without postmenopausal bleeding in order to determine whether symptomatic endometrial polyps have a genetic phenotype similar to that of endometrial cancer.

METHODS

Samples were obtained hysteroscopically from endometrial polyps of postmenopausal patients, and the expression of genetic markers involved in the pathogenesis of endometrial cancer (PTEN, BCL2, MLH1, and CTNNB1) was analyzed. The expression of these markers was then compared between patients with and without symptoms, which was characterized as postmenopausal bleeding. Other clinical characteristics of the patients, such as duration of menopause, polyp size, presence of systemic hypertension, diabetes mellitus, and smoking habits were also analyzed.

RESULTS

Samples from a total of 60 patients were obtained, as calculated for a test power of 0.80. No statistical differences (p > 0.05) were observed between the two groups concerning the expression of the studied endometrial cancer risk factor genes, or with regard to the clinical aspects evaluated.

CONCLUSION

The study found no evidence that symptomatic endometrial polyps have a similar phenotype to type 1 endometrial cancer; further studies are needed in order to establish whether endometrial polyps are in fact true cancer precursors, or simply raise cancer incidence due to a detection bias.

DHX32 Promotes Angiogenesis in Colorectal Cancer Through Augmenting β-catenin Signaling to Induce Expression of VEGFA

We previously reported that overexpression of DHX32 contributes to the growth and metastasis of colorectal cancer (CRC). However, the underlying mechanism is not largely characterized. Herein, we reported that DHX32 in CRC cells upregulated expression of vascular endothelial growth factor A (VEGFA) at the transcription level through interacting with and stabilizing β-catenin. This promoted the recruitment of host endothelial cells to the tumor, and therefore, formation of microvessel in the tumor. Xenograft model revealed that depletion of DHX32 in CRC cells significantly reduced the microvessel density in the grafts and suppressed the growth of grafts. Furthermore, the expression level of DHX32 was positively associated with microvessel density in human CRC and poor outcome of CRC patients. Therefore, the report demonstrates that DHX32 is a pro-angiogenic factor, that inhibition of DHX32-β-catenin pathway can provide a strategy for CRC treatment, and that the expression level of DHX32 has the potential to serve as a biomarker for CRC diagnosis and prognosis.

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DHX32 upregulates VEGFA expression through interacting with and stabilizing β-catenin.

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DHX32 promotes colorectal cancer cells to recruit endothelial cells and induces angiogenesis.

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DHX32 is associated with tumor angiogenesis and poor prognosis of colorectal cancer patients.

Tumor angiogenesis is required for cancer growth and metastasis. Understanding the molecular mechanism by which cancer cells promote angiogenesis is required to develop effective cancer treatment. In this study, we reported that DHX32 is a pro-angiogenic factor in colorectal cancer. Aberrantly expressed DHX32 promoted tumor angiogenesis by stabilizing β-catenin and increasing the expression of vascular endothelial growth factor. The results suggested that suppression of DHX32 can be of therapeutic value for colorectal cancer and that expression level of DHX32 has the potential to serve as a biomarker for colorectal cancer diagnosis and prognosis.

Epigenetic Alterations Affecting Transcription Factors and Signaling Pathways in Stromal Cells of Endometriosis

Endometriosis is characterized by growth of endometrial-like tissue outside the uterine cavity. Since its pathogenesis may involve epigenetic changes, we used Illumina 450K Methylation Beadchips to profile CpG methylation in endometriosis stromal cells compared to stromal cells from normal endometrium. We validated and extended the Beadchip data using bisulfite sequencing (bis-seq), and analyzed differential methylation (DM) at the CpG-level and by an element-level classification for groups of CpGs in chromatin domains. Genes found to have DM included examples encoding transporters (SLC22A23), signaling components (BDNF, DAPK1, ROR1, and WNT5A) and transcription factors (GATA family, HAND2, HOXA cluster, NR5A1, OSR2, TBX3). Intriguingly, among the TF genes with DM we also found JAZF1, a proto-oncogene affected by chromosomal translocations in endometrial stromal tumors. Using RNA-Seq we identified a subset of the DM genes showing differential expression (DE), with the likelihood of DE increasing with the extent of the DM and its location in enhancer elements. Supporting functional relevance, treatment of stromal cells with the hypomethylating drug 5aza-dC led to activation of DAPK1 and SLC22A23 and repression of HAND2, JAZF1, OSR2, and ROR1 mRNA expression. We found that global 5hmC is decreased in endometriotic versus normal epithelial but not stroma cells, and for JAZF1 and BDNF examined by oxidative bis-seq, found that when 5hmC is detected, patterns of 5hmC paralleled those of 5mC. Together with prior studies, these results define a consistent epigenetic signature in endometriosis stromal cells and nominate specific transcriptional and signaling pathways as therapeutic targets.