FoxM1 Directs STAT3 Expression Essential for Human Endometrial Stromal Decidualization

Exploring the role of endoplasmic reticulum stress in recurrent spontaneous abortion: Identification of diagnostic biomarkers and immune cell interactions

Dysregulated endoplasmic reticulum stress (ERS) is associated with recurrent spontaneous abortion (RSA) and is involved in the mechanisms that govern immune balance and vascular regulation at the maternal-fetal interface. The molecular intricacies of these mechanisms remain elusive. This study employed microarray and bioinformatics techniques to examine genetic abnormalities in endometrial tissues from RSA patients, with the objective of identifying potential ERS-related biomarkers. By integrating two publicly available microarray datasets, consisting of 88 RSA and 42 control samples, we conducted an extensive analysis, including differential expression, functional annotation, molecular interactions, and immune cell infiltration. Analysis of immune cell characteristics suggests an inflammatory immune imbalance as a potential contributor to RSA progression. Both innate and adaptive immunity were found to play roles in RSA development, with M1 macrophages constituting a significant proportion of immune infiltration. We identified five key ERS-associated genes (TMEM33, QRICH1, MBTPS2, ERN1, and BAK1) linked to immune-related mechanisms, with RT-qPCR results aligning with bioinformatics findings. Our research findings offer a fresh and comprehensive perspective on the ERS-related genes' pathways and interaction networks, offering significant insights for the advancement of innovative therapy techniques for RSA.

USP22 is required for human endometrial stromal cell proliferation and decidualization by deubiquitinating FoxM1

Despite significant advances in assisted reproductive technology (ART), recurrent implantation failure (RIF) still occurs in some patients. Poor endometrial receptivity and abnormal human endometrial stromal cell (HESC) proliferation and decidualization have been identified as the major causes. Ubiquitin-specific protease 22 (USP22) has been reported to participate in the decidualization of endometrial stromal cells in mice. However, the role of USP22 in HESC function and RIF development remains unknown. In this study, clinical endometrial tissue samples were gathered to investigate the involvement of USP22 in RIF, and HESCs were utilized to examine the molecular mechanisms of USP22 and Forkhead box M1 (FoxM1). The findings indicated a high expression of USP22 in the secretory phase of the endometrium. Knockdown of USP22 led to a notable reduction in the proliferation and decidualization of HESCs, along with a decrease in FoxM1 expression, while overexpression of USP22 yielded opposite results. Furthermore, USP22 was found to deubiquitinate FoxM1 in HESCs. Moreover, both USP22 and FoxM1 were downregulated in the endometria of patients with RIF. In conclusion, these results suggest that USP22 may have a significant impact on HESCs proliferation and decidualization through its interaction with FoxM1, potentially contributing to the underlying mechanisms of RIF pathogenesis.

Paradoxical role of phosphorylated STAT3 in normal fertility and the pathogenesis of adenomyosis and endometriosis†

Signal transducer and activator of transcription 3 (STAT3), when phosphorylated at tyrosine 705, plays an important role in endometrial stromal cell decidualization and the receptivity of the endometrial epithelium during embryo implantation. However, the function of phosphorylated STAT3 (p-STAT3) in normal uterine receptivity is distinct from that in adenomyosis and endometriosis. In normal pregnancy, STAT3 phosphorylation in the endometrial epithelium determines the success of embryo implantation by regulating uterine receptivity. Additionally, p-STAT3 promotes cellular proliferation and differentiation during endometrial decidualization, which is crucial for embryonic development. In contrast, excessive STAT3 phosphorylation occurs in adenomyosis and endometriosis, which may lead to disease progression. Therefore, achieving a delicate balance in STAT3 activation is crucial. This review aimed to focus on the current understanding and knowledge gaps regarding the control of p-STAT3 activity in normal and pathological endometrial processes. This topic is important because precise control of p-STAT3 production could alleviate the symptoms of adenomyosis and endometriosis, improve endometrial receptivity, and potentially mitigate infertility without compromising normal fertility processes.

O-Fucosylation of BMP1 promotes endometrial decidualization by activating BMP/Smad signaling pathway

Endometrial decidualization is critical to successful uterine receptivity and embryo implantation. Dysfunction of decidualization is associated with some pregnancy-related disorders, including miscarriage. Protein glycosylation is involved in many physiological and pathological processes. Protein O-fucosyltransferase 1 (poFUT1) is a key enzyme responsible for O-fucosylation biosynthesis on glycoproteins. Bone morphogenetic protein 1 (BMP1) is an essential glycoprotein in reproduction. However, the role and molecular mechanism of fucosylated BMP1 in endometrial stromal cell decidualization are still unknown. In the current study, we found that BMP1 contains a potential O-fucosylation site. Moreover, poFUT1 and BMP1 levels in the secretory phase are higher than those in the proliferative phase, and the highest level was observed in the human uterine tissues of early pregnancy, while a decrease of poFUT1 and BMP1 in the decidua was observed in miscarriage patients. Using human endometrial stromal cells (hESCs), we demonstrated that O-fucosylation of BMP1 was elevated after induced decidualization. Moreover, the increase of BMP1 O-fucosylation by poFUT1 promoted BMP1 secretion to the extracellular matrix, and more actively binds to CHRD. The binding of BMP1 and CHRD further released BMP4 originally bound to CHRD, and activated BMP/Smad signaling pathway, thereby accelerating the decidualization of human endometrial stromal cells. In summary, these results suggest that BMP1 O-fucosylation by poFUT1 could be a potential diagnostic and therapeutic target to predict miscarriage in early pregnancy examinations.

Long Non-Coding RNA-GDA-1 Promotes Keratinocyte Proliferation and Psoriasis Inflammation by Regulating the STAT3/NF-κB Signaling Pathway via Forkhead Box M1

Psoriasis is a chronic inflammatory skin disease associated with multiple comorbidities and complex pathogenesis. Long non-coding RNAs (lncRNAs) play an important regulatory role in many diseases, including psoriasis. In this study, We aimed to investigate the role and mechanism of lncRNA GDA-1 (GDA) in M5-treated psoriatic keratinocytes. GDA expression was significantly upregulated in psoriatic tissues and M5-treated keratinocytes. By silencing and overexpressing GDA in NHEKs and Ker-CT cells, we showed that GDA regulated proliferation and cell cycle and increased secretion of interleukin-1β (IL-1β), IL-6, and chemokine ligands 2 and 20 (CCL2 and CCL20). RNA sequencing after GDA silencing led to the identification of a close regulatory relationship between GDA and Forkhead Box M1 (FOXM1). GDA significantly influenced FOXM1 expression at both mRNA and protein levels and activated STAT3/NF-κB signaling pathways. STAT3 and NF-κB inhibition abrogated GDA effects on keratinocyte proliferation and inflammation. In conclusion, our study is the first to report that Lnc-GDA-1 distinctly regulates FOXM1 expression and mediates proliferation and inflammation of psoriatic keratinocytes through the STAT3/NF-κB signaling pathway, which may be a potent target for psoriasis treatment.

DNA Methylation of Window of Implantation Genes in Cervical Secretions Predicts Ongoing Pregnancy in Infertility Treatment

Window of implantation (WOI) genes have been comprehensively identified at the single cell level. DNA methylation changes in cervical secretions are associated with in vitro fertilization embryo transfer (IVF-ET) outcomes. Using a machine learning (ML) approach, we aimed to determine which methylation changes in WOI genes from cervical secretions best predict ongoing pregnancy during embryo transfer. A total of 2708 promoter probes were extracted from mid-secretory phase cervical secretion methylomic profiles for 158 WOI genes, and 152 differentially methylated probes (DMPs) were selected. Fifteen DMPs in 14 genes (BMP2, CTSA, DEFB1, GRN, MTF1, SERPINE1, SERPINE2, SFRP1, STAT3, TAGLN2, TCF4, THBS1, ZBTB20, ZNF292) were identified as the most relevant to ongoing pregnancy status. These 15 DMPs yielded accuracy rates of 83.53%, 85.26%, 85.78%, and 76.44%, and areas under the receiver operating characteristic curves (AUCs) of 0.90, 0.91, 0.89, and 0.86 for prediction by random forest (RF), naïve Bayes (NB), support vector machine (SVM), and k-nearest neighbors (KNN), respectively. SERPINE1, SERPINE2, and TAGLN2 maintained their methylation difference trends in an independent set of cervical secretion samples, resulting in accuracy rates of 71.46%, 80.06%, 80.72%, and 80.68%, and AUCs of 0.79, 0.84, 0.83, and 0.82 for prediction by RF, NB, SVM, and KNN, respectively. Our findings demonstrate that methylation changes in WOI genes detected noninvasively from cervical secretions are potential markers for predicting IVF-ET outcomes. Further studies of cervical secretion of DNA methylation markers may provide a novel approach for precision embryo transfer.

Increased FOXM1 Expression was Associated with the Prognosis and the Recruitment of Neutrophils in Endometrial Cancer

Background

Although the biological functions of Forkhead box protein M1 (FOXM1) were explored in a variety of cancer, to date, however, little attention has been paid to the situation of FOXM1 in EC endometrial cancer (EC).

Method

Bioinformatics analysis, including GEPIA, TIMER, cBioPortal, LinkedOmics, and STRING were used to analyze the FOXM1 gene expression, genetic alteration, and immune cell infiltration in EC. IHC staining, qPCR, cell viability, and migration assay were applied to identify the functions of FOXM1 in EC.

Results

FOXM1 was highly expressed in EC tissues and closely correlated with the prognosis of EC patients. FOXM1 knockdown inhibited EC cell proliferation and invasion as well as migration. FOXM1 genetic alteration was verified in EC patients. Coexpression network of FOXM1 indicated that it had roles in the EC cell cycle and the infiltration of immune cells in EC. Furthermore, bioinformatic and immunohistochemical analysis indicated that FOXM1 induced the increased CD276 expression and also enhanced the neutrophil recruitment in EC.

Conclusion

Our present study discovered a novel role of FOXM1 in EC, suggesting FOXM1 could be treated as a potential prognostic biomarker and immunotherapeutic target in EC diagnosis and treatment.

STAT3 in porcine endometrium during early pregnancy induces changes in extracellular matrix components and promotes angiogenesis†

A molecular interaction between maternal endometrium and implanting conceptus can lead to activation of a variety of transcription factors that regulate expression of several genes necessary for the process of embryo implantation. While, signal transducer and activator of transcription 3 (STAT3) is responsible for decidualization and epithelial remodeling in humans and mice, its role in porcine endometrium has not been explored before. In the present study, we observed a pregnancy dependent increase in gene and protein expression of STAT3. Phosphorylated STAT3 was predominantly present in the endometrium of pregnant animals in luminal and glandular epithelium and in the endothelium of blood vessels with a weak staining in stromal cells. Interleukins, IL-1β and IL-6, and epidermal growth factor (EGF)-induced STAT3 expression and phosphorylation in endometrial explants collected on Day 13 of the estrous cycle. Biological significance of STAT3 was evaluated by blocking its phosphorylation with STAT3-specific inhibitor, Stattic. Using porcine extracellular matrix (ECM) and adhesion molecule array, EGF was shown to induce changes in gene expression of ECM components: MMP1, MMP3, MMP12, LAMA1, SELL, and ICAM1, which was abrogated in the presence of Stattic. Transcriptional activity of STAT3 was observed in promoter regions of MMP3 and MMP12. Additionally, IL-6-induced STAT3 phosphorylation upregulated VEGF and VCAM1 abundances in endometrial-endothelial cells (EEC). Moreover, IL-6 resulted in an increase in EEC proliferation and capillary formation which was reversed in the presence of Stattic. Results of present study reveal a role for STAT3 phosphorylation in regulating extracellular matrix remodeling and angiogenesis in porcine endometrium to facilitate embryo implantation.

Effects of PAMK on lncRNA, miRNA, and mRNA expression profiles of thymic epithelial cells

Polysaccharides from Atractylodes macrocephala Koidz (PAMK) can promote the proliferation of thymocytes and improve the body's immunity. However, the effect of PAMK on thymic epithelial cells has not been reported. Studies have shown that miRNAs and lncRNAs are key factors in regulating cell proliferation. In this study, we found that PAMK could promote the proliferation of mouse medullary thymic epithelial cell line 1 (MTEC1) cells through CCK-8 and EdU experiments. To further explore its mechanism, we detected the effect of PAMK on the expression profiles of lncRNAs, miRNAs, and mRNAs in MTEC1 cells. The results showed that PAMK significantly affected the expression of 225 lncRNAs, 29 miRNAs, and 800 mRNAs. Functional analysis showed that these differentially expressed genes were significantly enriched in cell cycle, cell division, NF-kappaB signaling, apoptotic process, and MAPK signaling pathway. Finally, we used Cytoscape to visualize lncRNA-miRNA-mRNA(14 lncRNAs, 17 miRNAs, 171 mRNAs) networks based on ceRNA theory. These results suggest that lncRNAs and miRNAs may be involved in the effect of PAMK on the proliferation of MTEC1 cells, providing a new research direction for exploring the molecular mechanism of PAMK promoting the proliferation of thymic epithelial cells.

Maternal anxiety affects embryo implantation via impairing adrenergic receptor signaling in decidual cells

Recurrent implantation failure (RIF) is defined as the failed pregnancy after good embryo transfer over 3 cycles during in vitro fertilization (IVF).The human endometrium plays a vital role in providing the site for embryo implantation, with several factors implicated in unsatisfactory endometrial receptivity in RIF. Our present results revealed that women with pregnancy loss or infertility have a higher serum epinephrine level, indicating a potential correlation between psychological stress and pregnancy failure. RNA-sequencing of the tissues collected at the endometrial receptive phase in normal and RIF women showed that stress hormones could affect the functional status of endometrial receptivity. Subsequent analysis revealed that the epinephrine signaling acts as an important regulator of endometrial receptivity through the PI3K-AKT and FOXO1 signaling pathways. We also found that patients with RIF show attenuated expression of the alpha-2C-adrenergic receptor (ADRA2C) and that its down regulation induced by high level epinephrine could inhibit the decidualization. Early pregnant mice treated with stress showed high serum epinephrine levels, defective uterine adrenergic receptor expression, and low pregnancy rates. Altogether, our findings indicate that mental stress during early pregnancy can alter the functional status of endometrial receptivity.

SOX4 facilitates PGR protein stability and FOXO1 expression conducive for human endometrial decidualization

The establishment of pregnancy in human necessitates appropriate decidualization of stromal cells, which involves steroids regulated periodic transformation of endometrial stromal cells during the menstrual cycle. However, the potential molecular regulatory mechanism underlying the initiation and maintenance of decidualization in humans is yet to be fully elucidated. In this investigation, we document that SOX4 is a key regulator of human endometrial stromal cells decidualization by directly regulating FOXO1 expression as revealed by whole genomic binding of SOX4 assay and RNA sequencing. Besides, our immunoprecipitation and mass spectrometry results unravel that SOX4 modulates progesterone receptor (PGR) stability through repressing E3 ubiquitin ligase HERC4-mediated degradation. More importantly, we provide evidence that dysregulated SOX4–HERC4–PGR axis is a potential cause of defective decidualization and recurrent implantation failure in in-vitro fertilization (IVF) patients. In summary, this study evidences that SOX4 is a new and critical regulator for human endometrial decidualization, and provides insightful information for the pathology of decidualization-related infertility and will pave the way for pregnancy improvement.

Shp2 in uterine stromal cells critically regulates on time embryo implantation and stromal decidualization by multiple pathways during early pregnancy

Approximately 75% of failed pregnancies are considered to be due to embryo implantation failure or defects. Nevertheless, the explicit signaling mechanisms governing this process have not yet been elucidated. Here, we found that conditional deletion of the Shp2 gene in mouse uterine stromal cells deferred embryo implantation and inhibited the decidualization of stromal cells, which led to embryonic developmental delay and to the death of numerous embryos mid-gestation, ultimately reducing female fertility. The absence of Shp2 in stromal cells increased the proliferation of endometrial epithelial cells, thereby disturbing endometrial epithelial remodeling. However, Shp2 deletion impaired the proliferation and polyploidization of stromal cells, which are distinct characteristics of decidualization. In human endometrial stromal cells (hESCs), Shp2 expression gradually increased during the decidualization process. Knockout of Shp2 blocked the decidual differentiation of hESCs, while Shp2 overexpression had the opposite effect. Shp2 knockout inhibited the proliferation of hESCs during decidualization. Whole gene expression profiling analysis of hESCs during the decidualization process showed that Shp2 deficiency disrupted many signaling transduction pathways and gene expression. Analyses of hESCs and mouse uterine tissues confirmed that the signaling pathways extracellular regulated protein kinases (ERK), protein kinase B (AKT), signal transducer and activator of transcription 3 (STAT3) and their downstream transcription factors CCAAT/enhancer binding protein β (C/EBPβ) and Forkhead box transcription factor O1 (FOXO-1) were involved in the Shp2 regulation of decidualization. In summary, these results demonstrate that Shp2 plays a crucial role in stromal decidualization by mediating and coordinating multiple signaling pathways in uterine stromal cells. Our discovery possibly provides a novel key regulator of embryo implantation and novel therapeutic target for pregnancy failure.

Embryo implantation includes the establishment of uterine receptivity, blastocyst attachment, and endometrial decidualization. Disorders of this process usually induce pregnancy failure, resulting in women infertility. But the signaling mechanisms governing this process remain unclear. Here, using gene knockout mouse model and human endometrial stromal cells (hESCs), we identified a novel key regulator of embryo implantation, Shp2, which plays a crucial role in stromal decidualization by mediating and coordinating multiple signaling pathways in uterine stromal cells. Shp2 deficiency in mouse uterine stromal cells inhibited the uterine stromal decidualization, disturbing embryo implantation and embryonic development, ultimately reducing female fertility. The absence of Shp2 in hESCs also blocked the decidual differentiation. Our findings not only promote the understanding of peri-implantation biology, but may also provide a critical target for more effectively diagnose and/or treat women with recurrent implantation failure or early pregnancy loss.

Progesterone triggers Rho kinase-cofilin axis during in vitro and in vivo endometrial decidualization

STUDY QUESTION

Can a combination of the focussed protein kinase assays and a wide-scale proteomic screen pinpoint novel, clinically relevant players in decidualization in vitro and in vivo?

SUMMARY ANSWER

Rho-dependent protein kinase (ROCK) activity is elevated in response to the combined treatment with progesterone and 8-Br-cAMP during in vitro decidualization, mirrored by increase of ROCK2 mRNA and protein levels and the phosphorylation levels of its downstream target Cofilin-1 (CFL1) in secretory versus proliferative endometrium.

WHAT IS KNOWN ALREADY

Decidualization is associated with extensive changes in gene expression profile, proliferation, metabolism and morphology of endometrium, yet only a few underlying molecular pathways have been systematically explored. In vitro decidualization of endometrial stromal cells (ESCs) can be reportedly induced using multiple protocols with variable physiological relevance. In our previous studies, cyclic AMP (cAMP)/cAMP-dependent protein kinase (PKA)/prolactin axis that is classically upregulated during decidualization showed dampened activation in ESCs isolated from polycystic ovary syndrome (PCOS) patients as compared to controls.

STUDY DESIGN, SIZE, DURATION

In vitro decidualization studies were carried out in passage 2 ESCs isolated from controls (N = 15) and PCOS patients (N = 9). In parallel, lysates of non-cultured ESCs isolated from proliferative (N = 4) or secretory (N = 4) endometrial tissue were explored. The observed trends were confirmed using cryo-cut samples of proliferative (N = 3) or secretory endometrium (N = 3), and in proliferative or secretory full tissue samples from controls (N = 8 and N = 9, respectively) or PCOS patients (N = 10 for both phases).

PARTICIPANTS/MATERIALS, SETTING, METHODS

The activities of four target kinases were explored using kinase-responsive probes and selective inhibitors in lysates of in vitro decidualized ESCs and non-cultured ESCs isolated from tissue at different phases of the menstrual cycle. In the latter lysates, wide-scale proteomic and phosphoproteomic studies were further carried out. ROCK2 mRNA expression was explored in full tissue samples from controls or PCOS patients. The immunofluorescent staining of phosphorylated CFL1 was performed in full endometrial tissue samples, and in the in vitro decidualized fixed ESCs from controls or PCOS patients. Finally, the cellular migration properties were explored in live in vitro decidualized ESCs.

MAIN RESULTS AND THE ROLE OF CHANCE

During in vitro decidualization, the activities of PKA, protein kinase B (Akt/PKB), and ROCK are increased while the activity of casein kinase 2 (CK2) is decreased; these initial trends are observable after 4-day treatment (P < 0.05) and are further augmented following the 9-day treatment (P < 0.001) with mixtures containing progesterone and 8-Br-cAMP or forskolin. The presence of progesterone is necessary for activation of ROCK, yet it is dispensable in the case of PKA and Akt/PKB; in comparison to controls, PCOS patient-derived ESCs feature dampened response to progesterone. In non-cultured ESCs isolated from secretory vs proliferative phase tissue, only activity of ROCK is increased (P < 0.01). ROCK2 protein levels are slightly elevated in secretory versus proliferative ESCs (relative mean standard deviation < 50%), and ROCK2 mRNA is elevated in mid-secretory versus proliferative full tissue samples (P < 0.05) obtained from controls but not PCOS patients. Activation of ROCK2 downstream signalling results in increase of phospho-S3 CFL1 in secretory endometrium (P < 0.001) as well as in vitro decidualized ESCs (P < 0.01) from controls but not PCOS patients. ROCK2-triggered alterations in the cytoskeleton are reflected by the significantly decreased motility of in vitro decidualized ESCs (P < 0.05).

LARGE SCALE DATA

Proteomic and phosphoproteomic data are available via ProteomeXchange with identifier PXD026243.

LIMITATIONS, REASONS FOR CAUTION

The number of biological samples was limited. The duration of protocol for isolation of non-cultured ESCs from tissue can potentially affect phosphorylation pathways in cells, yet the possible artefacts were minimized by the identical treatment of proliferative and secretory samples.

WIDER IMPLICATIONS OF THE FINDINGS

The study demonstrated the benefits of combining the focussed kinase activity assay with wide-scale phosphoproteomics and showed the need for detailed elaboration of the in vitro decidualization protocols. ROCK was identified as the novel target of interest in decidualization, which requires closer attention in further studies-including the context of decidualization-related subfertility and infertility.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Estonian Ministry of Education and Research, and the Estonian Research Council (PRG1076, PRG454, PSG230 and PSG608), Enterprise Estonia (EU48695), Horizon 2020 innovation grant (ERIN, Grant no. EU952516) of the European Commission, the COMBIVET ERA Chair, H2020-WIDESPREAD-2018-04 (Grant agreement no. 857418), the Academy of Finland (Project grants 315921 and 321763), the Finnish Medical Foundation and The Sigrid Juselius Foundation. The authors confirm that they have no conflict of interest with respect to the content of this article.

CXCL10 Produced by HPV-Positive Cervical Cancer Cells Stimulates Exosomal PDL1 Expression by Fibroblasts via CXCR3 and JAK-STAT Pathways

Persistent infection with human papillomavirus (HPV) and immune surveillance failure may be the initiating factors for the carcinogenesis of cervical squamous cell carcinoma (CSCC). HPV infection might affect the innate immune pathway of cervical epithelial cells that constitute the "microenvironment" for tumor cells. Programmed death-ligand 1 (PD-L1) has been reported to be an immunosuppressor that helps cancer cells escape the actions of T cells. In the present study, CXCL10 was substantially upregulated both in cervical tissues of HPV infected patients with cervical intraepithelial neoplasia (CIN) or CSCC, as well as in HPV16 E6/E7 transgenic murine cervix. The HPV-positive (HPV+) cervical cancer cell lines SiHa and Caski secreted increased levels of CXCL10 compared to human foreskin fibroblasts (HFF-1), and its receptor CXCR3 was overexpressed in HFF-1. After co-culture with SiHa or Caski, the JAK-STAT signaling pathway and exosomal PD-L1 expression were both upregulated in HFF-1. Recombinant human CXCL10 induced JAK-STAT and PD-L1, while the CXCL10-CXCR3 and JAK-STAT inhibitors AMG487 or ruxolitinib reduced the expression of PD-L1 in HFF-1 cells. Furthermore, the upregulated expression of PD-L1 was verified in HPV+ but not HPV-negative (HPV-) patients with cervical cancers by analysis of tissue microarray cores in 25 cervical lesion patients (P < 0.05). The results indicate that HPV infection can induce cervical cancer cells to secrete CXCL10, which binds to CXCR3 in the surrounding fibroblast cells,leading to JAK-STAT pathway activation and the subsequent upregulated expression of exosomal PD-L1. These mechanisms may help HPV to escape immune response attack, leading to carcinogenesis.

Preimplantation factor modulates trophoblastic invasion throughout the decidualization of human endometrial stromal cells

BACKGROUND

Successful human embryo implantation requires the differentiation of endometrial stromal cells (ESCs) into decidual cells during a process called decidualization. ESCs express specific markers of decidualization, including prolactin, insulin-like growth factor-binding protein-1 (IGFBP-1), and connexin-43. Decidual cells also control of trophoblast invasion by secreting various factors, such as matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases. Preimplantation factor (PIF) is a recently identified, embryo-derived peptide with activities at the fetal-maternal interface. It creates a favorable pro-inflammatory environment in human endometrium and directly controls placental development by increasing the human trophoblastic cells' ability to invade the endometrium. We hypothesized that PIF's effects on the endometrium counteract its pro-invasive effects.

METHODS

We tested sPIF effect on the expression of three decidualization markers by RT-qPCR and/or immunochemiluminescence assay. We examined sPIF effect on human ESC migration by performing an in vitro wound healing assay. We analyzed sPIF effect on endometrial control of human trophoblast invasion by performing a zymography and an invasion assay.

RESULTS

Firstly, we found that a synthetic analog of PIF (sPIF) significantly upregulates the mRNA expression of IGFBP-1 and connexin-43, and prolactin secretion in ESCs - suggesting a pro-differentiation effect. Secondly, we showed that the HTR-8/SVneo trophoblastic cell line's invasive ability was low in the presence of conditioned media from ESCs cultured with sPIF. Thirdly, this PIF's anti-invasive action was associated with a specifically decrease in MMP-9 activity.

CONCLUSION

Taken as a whole, our results suggest that PIF accentuates the decidualization process and the production of endometrial factors that limit trophoblast invasion. By controlling both trophoblast and endometrial cells, PIF therefore appears to be a pivotal player in the human embryo implantation process.

Repression of FBXW7 by HES5 contributes to inactivation of the TGF-β signaling pathway and alleviation of endometriosis

Endometriosis (EMS) is a gynecologic disorder associated with infertility and characterized by the endometrial-type mucosa outside the uterine cavity. Currently available treatment modalities are limited to undesirable effects. Thus, in the present study, we sought to study the pathogenesis mechanism of EMS. For this purpose, the ectopic and eutopic endometrial tissues were resected from 86 patients with EMS and 54 infertile patients without EMS, respectively. The regulatory mechanism among HES family bHLH transcription factor 5 (HES5), transforming growth factor-beta (TGF-β)-induced factor 1 (TGIF1), F-box, and WD repeat domain containing 7 (FBXW7) was studied by performing co-immunoprecipitation, dual-luciferase reporter gene assay, and chromatin immunoprecipitation, respectively. A mouse model of EMS was established to verify the aforementioned regulatory mechanism in vivo. Upregulation of HES5 and TGIF1, as well as downregulation of FBXW7, was observed in EMS endometrial tissues and human endometrial stromal cells (hESCs), respectively. The overexpression of HES5 was found to suppress the FBXW7 transcription and TGIF1 degradation, resulting in the inactivation of the TGF-β signaling pathway, as well as inhibition of hESC proliferation and invasion, thereby enhancing apoptosis. Results from a mouse model of EMS showed that the presence of HES5 contributed to the alleviation of EMS. Collectively, we attempted to provide a mechanistic insight into the unrecognized roles of the HES5/FBXW7 in EMS progression.

The endometrial response to modulation of ligand-progesterone receptor pathways is reversible

OBJECTIVE

To study the impact of the progesterone receptor modulator (PRM), ulipristal acetate (UPA), on endometrial morphology and function.

DESIGN

Cross-sectional.

SETTING

University Research Institute.

PATIENT(S)

Endometrial biopsies from 16 patients with heavy menstrual bleeding with a structurally normal uterus or in association with structural abnormalities identified on radiological imaging (fibroids, adenomyosis or a combination of fibroids and adenomyosis).

INTERVENTION(S)

Participants received UPA (5 mg once daily) for three 12-week courses, each separated by 4 weeks without treatment.

MAIN OUTCOME MEASURE(S)

Gene expression by real-time quantitative reverse transcription polymerase chain reaction, immunohistochemistry, and digital image analysis were analyzed to investigate the endometrial impact of modulation of progesterone receptor pathways upon expression of steroid receptors, steroid metabolizing enzymes, cell proliferation, and progesterone-regulated genes in the same patients at 3 time points: before, during, and after discontinuation of PRM treatment.

RESULT(S)

Ulipristal acetate treatment resulted in increased messenger ribonucleic acid (mRNA) levels of steroid receptors compared with pretreatment secretory endometrium; decreased mRNA levels of 17- and 11-beta-hydroxysteroid dehydrogenases compared with pretreatment proliferative endometrium and pretreatment secretory endometrium; reduced cell proliferation compared with pretreatment proliferative endometrium; and altered mRNA levels of progesterone-regulated genes. A strong consistency between immunohistochemistry-digital image analysis and real-time quantitative reverse transcription polymerase chain reaction results was evident. Alterations in the mRNA levels and endometrial morphology returned to a pretreatment phenotype after the cessation of PRM exposure.

CONCLUSION(S)

The endometrial impact of the modulation of progesterone receptor pathways with PRM (UPA) treatment is reversible.

CLINICAL TRIAL REGISTRATION NUMBER

Ulipristal acetate versus conventional management of heavy menstrual bleeding (UCON) trial (EudraCT 2014-003408-65; REC14/LO/1602).

Resveratrol alleviates zea-induced decidualization disturbance in human endometrial stromal cells

Decidualization, which endows the endometrium competency to adopt developing embryo and maintain appropriate milieu for following growth, is a pivotal process for human pregnancy. The delicate collaboration between ovarian steroid hormones estrogen and progesterone governs the process of decidualization and subsequent establishment of embryo implantation. Mycotoxin zearalenone (ZEA) is well known as endocrine disruptor due to its potent estrogenic activity. In this study, we investigated effects of ZEA on decidualization of human endometrial stromal cells. Results indicated that ZEA exhibited its inhibitory action through nuclear translocation of ERα. ZEA exposure led to dampened progress of decidualization, which could be attenuated by estrogen receptor antagonist. Notably, resveratrol (RSV) administration restored impaired decidualization process by induction of anti-oxidative gene glutathione peroxidase 3 (GPX3). This study provides novel insights into the mechanism underlying adverse effects of ZEA in human decidual stromal cells and suggests RSV a potential therapeutic candidate to alleviate ZEA-induced cytotoxicity during decidualization.

Periconceptional exposure to lopinavir, but not darunavir, impairs decidualization: a potential mechanism leading to poor birth outcomes in HIV-positive pregnancies

STUDY QUESTION

Does HIV protease inhibitor (PI)-based combination antiretroviral therapy (cART) initiated at periconception affect key events in early pregnancy, i.e. decidualization and spiral artery remodeling?

SUMMARY ANSWER

Two PIs, lopinavir and darunavir, currently offered as cART options in HIV-positive pregnancies were evaluated, and we found that lopinavir-based cART, but not darunavir-based cART, impaired uterine decidualization and spiral artery remodeling in both human ex vivo and mouse in vivo experimental models.

WHAT IS KNOWN ALREADY

Early initiation of cART is recommended for pregnant women living with HIV. However, poor birth outcomes are frequently observed in HIV-positive pregnancies exposed to PI-based cART, especially when it is initiated prior to conception. The correlation between early initiation of PI-cART and adverse birth outcomes is poorly understood, due to lack of data on the specific effects of PI-cART on the early stages of pregnancy involving uterine decidualization and spiral artery remodeling.

STUDY DESIGN, SIZE, DURATION

Lopinavir and darunavir were evaluated in clinically relevant combinations using an ex vivo human first-trimester placenta-decidua explant model, an in vitro human primary decidual cell culture system, and an in vivo mouse pregnancy model. The first-trimester (gestational age, 6–8 weeks) human placenta-decidua tissue was obtained from 11 to 15 healthy women undergoing elective termination of pregnancy. C57Bl/6 female mice (four/treatment group) were administered either lopinavir-cART, darunavir-cART or water by oral gavage once daily starting on the day of plug detection until sacrifice.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Human: Spiral artery remodeling was assessed by immunohistochemical analysis of first-trimester placenta-decidua explant co-culture system. Trophoblast migration was measured using a placental explant culture. A primary decidual cell culture was used to evaluate the viability of immune cell populations by flow cytometry. Soluble factors, including biomarkers of decidualization and angiogenesis, were quantified by ELISA and Luminex assay using decidua-conditioned media.

Mouse: In the mouse pregnancy model, gestational day 6.5 or 9.5 implantation sites were used to assess decidualization, spiral artery remodeling and uterine natural killer (uNK) cell numbers by immunohistochemistry. Transcription factor STAT3 was assayed by immunohistochemistry in both human decidua and mouse implantation sites.

MAIN RESULTS AND THE ROLE OF CHANCE

Lopinavir-cART, but not darunavir-cART, impaired uterine decidualization and spiral artery remodeling in both experimental models. Lopinavir-cART treatment was also associated with selective depletion of uNK cells, reduced trophoblast migration and defective placentation. The lopinavir-associated decidualization defects were attributed to a decrease in expression of transcription factor STAT3, known to regulate decidualization. Our results suggest that periconceptional initiation of lopinavir-cART, but not darunavir-cART, causes defective maturation of the uterine endometrium, leading to impairments in spiral artery remodeling and placentation, thus contributing to the poor birth outcomes.

LARGE SCALE DATA

N/A

LIMITATIONS, REASONS FOR CAUTION

The human first-trimester placenta/decidua samples could only be obtained from healthy females undergoing elective termination of pregnancy. As biopsy is the only way to obtain first-trimester decidua from pregnant women living with HIV on PI-cART, ethics approval and participant consent are difficult to obtain. Furthermore, our animal model is limited to the study of cART and does not include HIV. HIV infection is also associated with immune dysregulation, inflammation, alterations in angiogenic factors and complement activation, all of which could influence decidual and placental vascular remodeling and modify any cART effects.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings provide mechanistic insight with direct clinical implications, rationalizing why the highest adverse birth outcomes are reported in HIV-positive pregnancies exposed to lopinavir-cART from conception. We demonstrate that dysregulation of decidualization is the mechanism through which lopinavir-cART, but not darunavir-cART, use in early pregnancy leads to poor birth outcomes. Although lopinavir is no longer a first-line regimen in pregnancy, it remains an alternate regimen and is often the only PI available in low resource settings. Our results highlight the need for reconsidering current guidelines recommending lopinavir use in pregnancy and indicate that lopinavir should be avoided especially in the first trimester, whereas darunavir is safe to use and should be the preferred PI in pregnancy.

Further, in current times of the COVID-19 pandemic, lopinavir is among the top drug candidates which are being repurposed for inclusion in clinical trials world-over, to assess their therapeutic potential against the dangerous respiratory disease. Current trials are also testing the efficacy of lopinavir given prophylactically to protect health care workers and people with potential exposures. Given the current extraordinary numbers, these might include women with early pregnancies, who may or may not be cognizant of their gestational status. This is a matter of concern as it could mean that women with early pregnancies might be exposed to this drug, which can cause decidualization defects. Our findings provide evidence of safety concerns surrounding lopinavir use in pregnancy, that women of reproductive age considering participation in such trials should be made aware of, so they can make a fully informed decision.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by funding from the Canadian Institutes of Health Research (CIHR) (PJT-148684 and MOP-130398 to L.S.). C.D. received support from CIHR Foundation (FDN143262 to Stephen Lye). S.K. received a TGHRI postdoctoral fellowship. The authors declare that there are no conflicts of interest. L.S. reports personal fees from ViiV Healthcare for participation in a Women and Transgender Think Tank.

Silencing of FoxM1 blocks growth, migration and invasion of papillary thyroid carcinoma cells

The aim of the present study was to investigate the effect of Forkhead box transcription factor M1 (FoxM1)-silencing on the growth, migration and invasion of K1 human papillary thyroid carcinoma (PTC) cells. The effect of FoxM1-small interfering RNA (siRNA) in K1 cells was detected by western blot analysis. FoxM1-siRNA and control siRNA were transfected into K1 cells using Lipofectamine^® 2000 (transfection group, T) and the non-meaning sequence group (NM). K1 cells exposed to PBS solution comprised the blank control group (CON). Cell proliferation ability was detected using an MTT assay. Cell migration and invasion was detected by the single cell scratch test and Transwell invasion assay, respectively. Western blot analysis indicated that FoxM1 siRNA downregulated the expression of FoxM1 protein. Cell proliferation, migration and invasion were significantly lower in the T group compared with the NM and CON groups (P<0.05). These results indicated that silencing of FoxM1 expression could block growth, invasion and migration of K1 cells. This study may provide a novel target gene for targeted therapy of PTC.

Decreased Endometrial IL-10 Impairs Endometrial Receptivity by Downregulating HOXA10 Expression in Women with Adenomyosis

Objective

The aim of this study was to investigate the potential role of IL-10 in regulating the receptivity marker HOXA10 in the endometrium of women with adenomyosis.

Methods

The expression levels of IL-10, HOXA-10, STAT3, and p-STAT3 in the endometrium of women with adenomyosis and controls were examined by means of western blotting and immunohistochemistry. The expression of the HOXA10 protein in Ishikawa cells treated with rIL-10 was examined by western blotting. The attachment rate of BeWo cell spheroids to Ishikawa cells treated with rIL-10 was expressed as a percentage of the total number of spheroids.

Results

The expression levels of HOXA10 and IL-10 in the adenomyosis group were significantly lower than those in the control group, and there was a positive correlation between HOXA10 and IL-10 protein levels in all the women examined. rIL-10 increased HOXA10 expression in a concentration- and time-dependent manner by inducing the phosphorylation of STAT3 in Ishikawa cells. Treatment with rIL-10 promoted the attachment of BeWo spheroids to Ishikawa cells, which was reversed by the inhibition of STAT3 phosphorylation. The expression of p-STAT3 in the adenomyosis group was significantly lower than that in the control group, and there was a positive correlation between IL-10 and p-STAT3 protein levels in all the women examined.

Conclusions

Both IL-10 and HOXA10 levels in the endometrium are significantly reduced in women with adenomyosis compared with those in control women. The phosphorylation of STAT3 has been proven to be a critical mediator between IL-10 and HOXA10, which may play critical roles in embryo implantation.

Circ-8073 regulates CEP55 by sponging miR-449a to promote caprine endometrial epithelial cells proliferation via the PI3K/AKT/mTOR pathway

Circular RNAs (circRNAs) are a large class of endogenous non-coding RNAs that function as regulators in various cells and tissues. Here, the function and mechanism of circRNA8073 (Circ-8073) on endometrial epithelial cells (EECs) and the development of endometrial receptivity were investigated in dairy goats. Circ-8073 could bind to and inhibit miR-449a activity. Circ-8073 binding to the target site of miR-449a had a negative feedback relationship. Centrosomal protein55 (CEP55) was a direct target gene of miR-449a, and Circ-8073 could increase the expression levels of CEP55 by sponging miR-449a in EECs in vitro. Circ-8073/miR-449a/CEP55 could promote EECs proliferation via the PI3K/AKT/mTOR pathway. In addition, CEP55 could regulate the expression levels of vascular endothelial growth factor (VEGF) and forkhead box M1 (FOXM1) in EECs, which contributed to the development of endometrial receptivity. These findings showed that Circ-8073 regulated CEP55 by sponging miR-449a to promote EEC proliferation via the PI3K/AKT/mTOR pathway, suggesting that it could function as a regulator in the development of endometrial receptivity in dairy goats.

Analysis of chromatin accessibility in decidualizing human endometrial stromal cells

Spontaneous decidualization of the endometrium in response to progesterone signaling is confined to menstruating species, including humans and other higher primates. During this process, endometrial stromal cells (EnSCs) differentiate into specialized decidual cells that control embryo implantation. We subjected undifferentiated and decidualizing human EnSCs to an assay for transposase accessible chromatin with sequencing (ATAC-seq) to map the underlying chromatin changes. A total of 185,084 open DNA loci were mapped accurately in EnSCs. Altered chromatin accessibility upon decidualization was strongly associated with differential gene expression. Analysis of 1533 opening and closing chromatin regions revealed over-representation of DNA binding motifs for known decidual transcription factors (TFs) and identified putative new regulators. ATAC-seq footprint analysis provided evidence of TF binding at specific motifs. One of the largest footprints involved the most enriched motif-basic leucine zipper-as part of a triple motif that also comprised the estrogen receptor and Pax domain binding sites. Without exception, triple motifs were located within Alu elements, which suggests a role for this primate-specific transposable element (TE) in the evolution of decidual genes. Although other TEs were generally under-represented in open chromatin of undifferentiated EnSCs, several classes contributed to the regulatory DNA landscape that underpins decidual gene expression.-Vrljicak, P., Lucas, E. S., Lansdowne, L., Lucciola, R., Muter, J., Dyer, N. P., Brosens, J. J., Ott, S. Analysis of chromatin accessibility in decidualizing human endometrial stromal cells.

Mycobacterial heat shock protein 65 mediated metabolic shift in decidualization of human endometrial stromal cells

Successful implantation is dependent on the appropriate decidualization of endometrial stromal cells for the establishment of pregnancy in women. Mycobacterial heat shock protein 65 (HSP65) is involved in pathogenesis of the genital tuberculosis (GTB), one of the common causes of infertility in emerging countries. Though implantation failure appears to be the major cause, understanding the status of decidualizaiton process in women diagnosed with GTB has not been thoroughly addressed. We, therefore, explored the effect of HSP65 protein on the endometrial cell metabolism during in vitro decidualization. In order to identify the cellular metabolism of decidual cells with and without HSP65 treatment, proton NMR based characterization of metabolites extracted from cells and culture media were performed. In presence of HSP65, significant reduction in the decidual phenotype of endometrial stromal cells and prolactin expression is suggestive of impairment in decidualization. The intracellular and extracellular metabolic changes in HSP65 treated endometrial stromal cells produced a distinct pattern, reflecting the interaction between the protein and cellular metabolism. HSP65 mediated dysregulation in cellular metabolism is associated with poor decidualization. Besides enriching the present knowledge on metabolic changes underlying stromal cells decidualization, these findings assist in identifying potential molecular causes for decidualization failure in GTB women.

Roles of FoxM1 in cell regulation and breast cancer targeting therapy

Forkhead box M1 (FoxM1) is an oncogenic transcription factor involved in a wide variety of cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism and DNA damage response. It is overexpressed in many human cancers, especially in breast cancers. Posttranslational modifications are known to play an important role in regulating the expression and transcriptional activity of FoxM1. In this review, we characterize the posttranslational modifications of FoxM1, summarize modifications of FoxM1 by different kinases, explore the relationship between the different sites of modifications and comprehensively describe how posttranslational modifications to regulate the function of FoxM1 by changing protein stability, nucleus localization and transcriptional activity. Additionally, we systematically summarize the roles of FoxM1 in breast cancer occurrence, therapy and drug resistance. The purpose of this paper tries to give a better understanding of the regulatory mechanisms of FoxM1 in cell regulation and highlights potential of a new method for breast cancer therapy by targeting FoxM1.

Dysregulation of In Vitro Decidualization of Human Endometrial Stromal Cells by Insulin via Transcriptional Inhibition of Forkhead Box Protein O1

Insulin resistance and compensatory hyperinsulinemia are characteristic features of obesity and polycystic ovary syndrome, and both are associated with reduced fertility and implantation. There is little knowledge about the effect of insulin on the decidualization process and previous findings are contradictory. We investigated the effect of insulin on the regulation of forkhead box protein O1 (FOXO1), one of the most important transcription factors during decidualization. Endometrial stromal cells were isolated from six healthy, regularly menstruating women and decidualized in vitro. Gene expression levels of six putative FOXO1 target genes (including insulin-like growth factor binding protein-1 (IGFBP1) and prolactin (PRL)) were measured with Real-Time PCR following FOXO1 inhibition or insulin treatment. PI3K inhibition was used to identify the possible mechanism behind regulation. Subcellular localization of FOXO1 was analyzed with immunofluorescence. All the genes (IGFBP1, CTGF, INSR, DCN, LEFTY2), except prolactin, were evaluated as FOXO1 target genes in decidualizing stromal cells. Insulin caused a significant dose-dependent inhibition of the verified FOXO1 target genes. It was also demonstrated that insulin regulated FOXO1 target genes by transcriptional inactivation and nuclear export of FOXO1 via PI3K pathway. However, insulin did not inhibit the morphological transformation of endometrial stromal cells via transcriptional inactivation of FOXO1. This study provides new insights on the action of insulin on the endometrium via regulation of FOXO1. It is suggested that hyperinsulinemia results in dysregulation of a high number of FOXO1 controlled genes that may contribute to endometrial dysfunction and reproductive failure. Our findings may illuminate possible reasons for unexplained infertility.

The Transcriptomic Evolution of Mammalian Pregnancy: Gene Expression Innovations in Endometrial Stromal Fibroblasts

The endometrial stromal fibroblast (ESF) is a cell type present in the uterine lining of therian mammals. In the stem lineage of eutherian mammals, ESF acquired the ability to differentiate into decidual cells in order to allow embryo implantation. We call the latter cell type "neo-ESF" in contrast to "paleo-ESF" which is homologous to eutherian ESF but is not able to decidualize. In this study, we compare the transcriptomes of ESF from six therian species: Opossum (Monodelphis domestica; paleo-ESF), mink, rat, rabbit, human (all neo-ESF), and cow (secondarily nondecidualizing neo-ESF). We find evidence for strong stabilizing selection on transcriptome composition suggesting that the expression of approximately 5,600 genes is maintained by natural selection. The evolution of neo-ESF from paleo-ESF involved the following gene expression changes: Loss of expression of genes related to inflammation and immune response, lower expression of genes opposing tissue invasion, increased markers for proliferation as well as the recruitment of FOXM1, a key gene transiently expressed during decidualization. Signaling pathways also evolve rapidly and continue to evolve within eutherian lineages. In the bovine lineage, where invasiveness and decidualization were secondarily lost, we see a re-expression of genes found in opossum, most prominently WISP2, and a loss of gene expression related to angiogenesis. The data from this and previous studies support a scenario, where the proinflammatory paleo-ESF was reprogrammed to express anti-inflammatory genes in response to the inflammatory stimulus coming from the implanting conceptus and thus paving the way for extended, trans-cyclic gestation.

Human Decidual Stromal Cells as a Component of the Implantation Niche and a Modulator of Maternal Immunity

The human decidua is a specialized tissue characterized by embryo-receptive properties. It is formed during the secretory phase of menstrual cycle from uterine mucosa termed endometrium. The decidua is composed of glands, immune cells, blood and lymph vessels, and decidual stromal cells (DSCs). In the process of decidualization, which is controlled by oestrogen and progesterone, DSCs acquire specific functions related to recognition, selection, and acceptance of the allogeneic embryo, as well as to development of maternal immune tolerance. In this review we discuss the relationship between the decidualization of DSCs and pathological obstetrical and gynaecological conditions. Moreover, the critical influence of DSCs on local immune cells populations as well as their relationship to the onset and maintenance of immune tolerance is described.

Progesterone-Regulated Endometrial Factors Controlling Implantation

The steroid hormone progesterone (P), acting via the progesterone receptor (PR) isoforms, PR-A and PR-B, exerts a profound influence on uterine functions during early gestation. In recent years, chromatin immunoprecipitation-sequencing in combination with microarray-based gene expression profiling analyses have revealed that the PR isoforms control a substantially large cistrome and transcriptome during endometrial differentiation in the human and the mouse. Genetically engineered mouse models have established that several PR-regulated genes, such as Ihh, Bmp2, Hoxa10, and Hand2, are essential for implantation and decidualization. PR-A and PR-B also collaborate with other transcription factors, such as FOS, JUN, C/EBPβ and STAT3, to regulate the expression of many target genes that functions in concert to properly control uterine epithelial proliferation, stromal differentiation, angiogenesis, and local immune response to render the uterus 'receptive' and allow embryo implantation. This review article highlights recent work describing the key PR-regulated pathways that govern critical uterine functions during establishment of pregnancy.