Expression of Nodal, Cripto, SMAD3, phosphorylated SMAD3, and SMAD4 in the proliferative endometrium of women with endometriosis

Assessment of BMP7, SMAD4, and CDH1 Expression Profile and Regulatory miRNA-542-3p in Eutopic and Ectopic Endometrium of Women with Endometriosis

Alterations in the expression of numerous genes and the miRNAs that are recognized as their regulators in the endometrial cells of women with endometriosis may disrupt the intracellular signaling pathways associated with epithelial–mesenchymal transition (EMT). So far, the functional role of BMP7 in endometrial physiology has been confirmed, especially in the context of fertility, but the role of the activation of a specific mechanism operating through the BMP–SMAD–CDH1 axis in the formation of endometrial lesions remains unexplored. The aim of this study was to evaluate the expression profile of miR-542-3p and the EMT markers (BMP7, SMAD4, CDH1) in matched eutopic endometrium (EUE) and ectopic endometrium (ECE) samples from women with endometriosis in relation to healthy women. The levels of expression of the studied genes and miRNA in peripheral blood mononuclear cells (PBMCs) obtained from women diagnosed with endometriosis and those without the disease were also evaluated. Fifty-four patients (n = 54: with endometriosis—n = 29 and without endometriosis—n = 25) were included in the study. A comparative analysis of the relative mean expression values (RQ) of the studied mRNA and miRNA assessed by RT-qPCR demonstrated downregulation of BMP7, SMAD4, and CDH1 expression in ectopic lesions and upregulation in the eutopic endometrium compared with the control group. In the eutopic tissue of women with endometriosis, miR-542-3p expression was similar to that of the control but significantly lower than in endometrial lesions. We also confirmed a trend towards a negative correlation between miR-542-3p and BMP7 in ectopic tissue, and in PBMC, a significant negative correlation of miR-542-3p with further BMP signaling genes, i.e., SMAD4 and CDH1, was observed. These results indicate that the miRNA selected by us may be a potential negative regulator of BMP7-SMAD4-CDH1 signaling associated with EMT. The different patterns of BMP7, SMAD4, and CDH1 gene expression in ECE, EUE, and the control endometrium observed by us suggests the loss of the endometrial epithelium phenotype in women with endometriosis and demonstrates their involvement in the pathogenesis and pathomechanism of this disease.

The Expression of TGF-β1, SMAD3, ILK and miRNA-21 in the Ectopic and Eutopic Endometrium of Women with Endometriosis

The molecular pathogenesis of endometriosis has been associated with pathological alterations of protein expression via disturbances in homeostatic genes, miRNA expression profiles, and signaling pathways that play an essential role in the epithelial-mesenchymal transition (EMT) process. TGF-β1 has been hypothesized to play a key role in the development and progression of endometriosis, but the activation of a specific mechanism via the TGF-β-SMAD-ILK axis in the formation of endometriotic lesions is poorly understood. The aim of this study was to assess the expression of EMT markers (TGF-β1, SMAD3, ILK) and miR-21 in ectopic endometrium (ECE), in its eutopic (EUE) counterpart, and in the endometrium of healthy women. The expression level of the tested genes and miRNA was also evaluated in peripheral blood mononuclear cells (PBMC) in women with and without endometriosis. Fifty-four patients (n = 54; with endometriosis, n = 29, and without endometriosis, n = 25) were enrolled in the study. The expression levels (RQ) of the studied genes and miRNA were evaluated using qPCR. Endometriosis patients manifested higher TGF-β1, SMAD3, and ILK expression levels in the eutopic endometrium and a decreased expression level in the ectopic lesions in relation to control tissue. Compared to the endometrium of healthy participants, miR-21 expression levels did not change in the eutopic endometrium of women with endometriosis, but the RQ was higher in their endometrial implants. In PBMC, negative correlations were found between the expression level of miR-21 and the studied genes, with the strongest statistically significant correlation observed between miR-21 and TGF-β1. Our results suggest the loss of the endometrial epithelial phenotype defined by the differential expression of the TGF-β1, SMAD3 and ILK genes in the eutopic and ectopic endometrium. We concluded that the TGF-β1-SMAD3-ILK signaling pathway, probably via a mechanism related to the EMT, may be important in the pathogenesis of endometriosis. We also identified miR-21 as a possible inhibitor of this TGF-β1-SMAD3-ILK axis.

Hormonal treatments for endometriosis: The endocrine background

Endometriosis is a benign uterine disorder characterized by menstrual pain and infertility, deeply affecting women's health. It is a chronic disease and requires a long term management. Hormonal drugs are currently the most used for the medical treatment and are based on the endocrine pathogenetic aspects. Estrogen-dependency and progesterone-resistance are the key events which cause the ectopic implantation of endometrial cells, decreasing apoptosis and increasing oxidative stress, inflammation and neuroangiogenesis. Endometriotic cells express AMH, TGF-related growth factors (inhibin, activin, follistatin) CRH and stress related peptides. Endocrine and inflammatory changes explain pain and infertility, and the systemic comorbidities described in these patients, such as autoimmune (thyroiditis, arthritis, allergies), inflammatory (gastrointestinal/urinary diseases) and mental health disorders.The hormonal treatment of endometriosis aims to block of menstruation through an inhibition of hypothalamus-pituitary-ovary axis or by causing a pseudodecidualization with consequent amenorrhea, impairing the progression of endometriotic implants. GnRH agonists and antagonists are effective on endometriosis by acting on pituitary-ovarian function. Progestins are mostly used for long term treatments (dienogest, NETA, MPA) and act on multiple sites of action. Combined oral contraceptives are also used for reducing endometriosis symptoms by inhibiting ovarian function. Clinical trials are currently going on selective progesterone receptor modulators, selective estrogen receptor modulators and aromatase inhibitors. Nowadays, all these hormonal drugs are considered the first-line treatment for women with endometriosis to improve their symptoms, to postpone surgery or to prevent post-surgical disease recurrence. This review aims to provide a comprehensive state-of-the-art on the current and future hormonal treatments for endometriosis, exploring the endocrine background of the disease.

Investigating the role of EGF-CFC gene family in recurrent pregnancy loss through bioinformatics and molecular approaches

Recurrent pregnancy loss (RPL) is the most common reproductive failure, reaching 1-5% of women throughout their lives, and having unknown etiology in 50% of the cases. In humans, EGF-CFC1 (Epidermal Growth Factors & Cripto/FRL-1/Cryptic) gene family is composed by TDGF1 and CFC1, two developmental genes. The aim of this study was to investigate the role of EGF-CFC on RPL. To this, multiple approaches were performed; we conducted an expression analysis of TDGF1 and CFC1 using publicly available data from Gene Omnibus Expression (GEO), systems biology analyses and functional prediction; and a molecular analysis carried out in a case-control study. Our GEO analysis showed a decrease in TDGF1 expression in the endometrium (p=0.049) and CFC1 expression in placenta (p=0.015) of women with RPL. Network analysis, gene ontology and literature pointed to a strong connection between EGF-CFC1 gene family to pathways that play key roles during pregnancy, including TGF-β, c-Src/MAPK/AKT, Notch, TNFα, IFNγ and IL-6. A pathogenicity score developed for this gene family showed that the c.-14+1429T>C (rs3806702) variant in the TDGF1 and the p.Arg47Gln (rs201431919) variant in CFC1 gene would be the ones with the highest deleterious effect for RPL. In the case-control study, which involved 149 women with RPL and 159 controls, no statistical difference was observed in the allele and genotype distributions of the variants studied in the two groups. In this study, we performed extensive bioinformatics analysis for biomarker prioritization followed by experimental validation of proposed selected markers. Although there is no statistical difference in the frequencies of these variants between RPL and controls, the expression analysis results suggest that TDGF1 and CFC1 genes might play a role in RPL. In addition, systems biology analyzes raise the hypothesis that genes in other signaling pathways that may be related to RPL as good candidates for future studies.Abbreviations RPL: recurrent pregnancy loss; EGF-CFC1: Epidermal Growth Factors - Cripto/FRL-1; GEO: Gene Omnibus Expression; KEGG: Kyoto Encyclopedia of Genes and Genomes.

Immunolocalization of stem/progenitor cell biomarkers Oct-4, C-kit and Musashi-1 in endometriotic lesions

BACKGROUND

Human endometrium harbors stem/progenitor cells (SPCs) that may contribute to the establishment of endometriosis when seeded outside the uterus. Oct-4, C-kit and Musashi-1 are some of the many proteins used to characterize SPCs, but their association with endometriosis is uncertain.

OBJECTIVE AND DESIGN

In this study, specimens of normal endometrium (n = 12), eutopic endometrium from women with endometriosis (n = 9), superficial peritoneal endometriosis (SUP, n = 12) and deep endometriosis (DE, n = 13) lesions were evaluated for localization and intensity of immunostaining for Oct-4, C-kit and Musashi-1.

RESULTS

The three markers were abundantly expressed in normal endometrium, eutopic endometrium from endometriosis patients, SUP and DE specimens. Oct-4 and C-kit expression did not vary across groups as regards intensity or frequency. C-kit staining signal was seldom detected in vascular endothelium of normal or eutopic endometrium from endometriosis patients; however, it was positive in 67% of the SUP lesions and in 25% of the DE lesions (p = 0.042). Musashi-1 was expressed in some endometriotic glands as cell clusters, but its signal was similar between the four types of tissue (p = 0.971) CONCLUSION: The wide distribution of Oct-4, C-kit and Musashi-1 in endometria of patients with and without endometriosis and in SUP and DE endometriotic lesions suggests that these markers are not suitable for the in situ characterization of endometrial SPCs and should not be taken as surrogates for the study of SPCs in the pathogenesis of endometriosis.

Genetic and in silico analysis show a role of SMAD3 on recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is one of the most common reproductive failures affecting 1-5% of couples. Smad3 is an effector of signalling of the Transforming Growth Factors-β superfamily (TGF-β), regulating the transcription of several target genes of these cytokines. The objective of this study was to evaluate the influence of a variant on SMAD3 (rs17293443) in RPL. A case-control study was carried out with 149 women who experienced RPL and 159 controls, as well as bioinformatics tools to determine the role of this variant in this condition. Our study showed an allelic (p = 0.023) and genotypic (p < 0.01) association of this variant with the RPL. Our functional in silico predictions suggest that this variant causes a change in SMAD3 expression levels. Alterations in the expression of this gene can directly compromise the Smad3-dependent signalling pathway that is fundamental for key processes for gestation such as steroid hormone regulation and implantation, as demonstrated by ontologies analyses performed and the literature. Our findings regarding the involvement of Smad3 on RPL are a novelty in this field, and they seem to be promising to the clinical management of this condition.

Maternal Cripto is critical for proper development of the mouse placenta and the placental vasculature

INTRODUCTION

The growth and survival of the mammalian fetus is highly dependent on the placenta. Several research groups have demonstrated the involvement of different transforming growth factor-beta (TGFβ) superfamily members and their related receptors in placentation. Cripto is a member of the epidermal growth factor-Cripto1/FRL1/Cryptic protein family and plays a critical role in embryonic development, stem cell maintenance and tumor progression through TGFβ-dependent and independent pathways. Several studies have suggested that Cripto may also have a role in female reproduction and pregnancy maintenance, but its specific role remains elusive.

METHODS

We used a conditional knockout mouse model in which Cripto is deleted from the uterus using a loxP-Cre system. Cripto cKO females were mated with wildtype males and dissections were performed at different timepoints during pregnancy for assessment of the number and size of the implantation sites, resorption sites, fetal weight and placental development. Histology, IF staining and quantitative PCR were employed to analyze the placentation process.

RESULTS

We found that loss of maternal Cripto results in defective placentation, decreased vascularization within the placental labyrinth and leads to intrauterine growth restriction and fetal death. We further demonstrated that components of the VEGF and Notch signaling pathways are downregulated in Cripto cKO decidua and placenta potentially contributing to defects in the development of the vasculature at maternal-fetal interface.

DISCUSSION

These findings demonstrate that maternal Cripto is involved in the maternal-fetal communications required for proper development of the placenta and placental vasculature.

Maternal Cripto is required for proper uterine decidualization and peri-implantation uterine remodeling

Cripto encodes for a cell surface receptor whose role in embryonic development and stem cell maintenance has been studied. Cripto mRNA and protein have been detected in the human uterus at all stages of the menstrual cycle. To date, there is not much known about Cripto's role in female reproduction. As Cripto null Knockout (KO) is embryonic lethal, we created a conditional KO (cKO) mouse model in which Cripto is deleted only in the reproductive tissues using a Cre-loxP system. Pregnancy rate and number of pups per litter were evaluated as general fertility indices. We observed a significant decrease in pregnancy rate and litter size with loss of uterine Cripto indicating that Cripto cKO females are subfertile. We showed that although the preimplantation period is normal in Cripto cKO females, 20% of cKO females fail to establish pregnancy and an additional 20% of females undergo full litter loss after implantation between day 5.5 postcoitum (d5.5pc) and d8.5pc. We showed that subfertility caused by loss of uterine Cripto is due to defects in uterine decidualization, remodeling, and luminal closure and is accompanied by significant downregulation of Bmp2, Wnt4 and several components of Notch signaling pathway which all are known to be important factors in uterine remodeling and decidualization. Our study demonstrates that Cripto is expressed in the uterus during critical stages of early pregnancy and its deletion results in subfertility due to implantation failure, impaired peri-implantation uterine remodeling and impaired uterine decidualization.

Sphingosine 1-phosphate receptors are dysregulated in endometriosis: possible implication in transforming growth factor β-induced fibrosis

OBJECTIVE

To study the molecular mechanisms involved in the appearance of the fibrotic trait in endometriosis by investigating whether the signaling pathway of the bioactive sphingolipid sphingosine 1-phosphate (S1P) was altered in endometriotic lesions.

DESIGN

Case-control laboratory study.

SETTING

University research institute and university hospital.

PATIENT(S)

A total of 75 women, with and without endometriosis, were included in the study.

INTERVENTIONS(S)

Endometrial samples were obtained from women affected (n = 15 endometrioma [OMA]; n = 30 deep infiltrating endometriosis [DIE]) and not (n = 30) by endometriosis by means of laparoscopic surgery, followed by clinical and imaging investigation and checking for the expression of fibrosis markers and genes implicated in S1P metabolism and signaling by means of real-time polymerase chain reaction.

MAIN OUTCOME MEASURE(S)

The role of the S1P signaling axis in endometriosis-associated fibrosis was studied in vitro, where RNA interference approaches were used to investigate if S1P synthesis by sphingosine kinases (SKs) and specific S1P receptors (S1PRs) are implicated in the profibrotic effect of the cytokine transforming growth factor (TGF) β1.

RESULT(S)

mRNA expression analysis of S1PR demonstrated a deep dysregulation of S1P signaling in endometriosis, characterized by increased expression of fibrosis markers: S1P₁ was transcriptionally more expressed in OMA, and S1P₃ and S1P₅ mRNA levels were significantly augmented in both OMA and DIE. SK1 and its activating protein calcium- and integrin-binding protein 1 (CIB1) were significantly up-regulated in OMA and DIE. A crucial role for the SK/S1PR axis in the profibrotic effect elicited by TGFβ1 was highlighted in vitro.

CONCLUSION(S)

The S1P signaling axis may represent a useful biomarker or innovative pharmacologic target for endometriosis.

A Multidisciplinary Review of the Roles of Cripto in the Scientific Literature Through a Bibliometric Analysis of its Biological Roles

Cripto is a small glycosylphosphatidylinisitol (GPI)-anchored and secreted oncofetal protein that plays important roles in regulating normal physiological processes, including stem cell differentiation, embryonal development, and tissue growth and remodeling, as well as pathological processes such as tumor initiation and progression. Cripto functions as a co-receptor for TGF-β ligands such as Nodal, GDF1, and GDF3. Soluble and secreted forms of Cripto also exhibit growth factor-like activity and activate SRC/MAPK/PI3K/AKT pathways. Glucose-Regulated Protein 78 kDa (GRP78) binds Cripto at the cell surface and has been shown to be required for Cripto signaling via both TGF-β and SRC/MAPK/PI3K/AKT pathways. To provide a comprehensive overview of the scientific literature related to Cripto, we performed, for the first time, a bibliometric analysis of the biological roles of Cripto as reported in the scientific literature covering the last 10 years. We present different fields of knowledge in comprehensive areas of research on Cripto, ranging from basic to translational research, using a keyword-driven approach. Our ultimate aim is to aid the scientific community in conducting targeted research by identifying areas where research has been conducted so far and, perhaps more importantly, where critical knowledge is still missing.

Different macrophages equally induce EMT in endometria of adenomyosis and normal

Endometrial cells and microenvironment are two important factors in the pathogenesis of adenomyosis. Our previous study demonstrated that macrophages can induce eutopic epithelial cells of adenomyosis to suffer from epithelial–mesenchymal transition (EMT). The aim of this study is to detect whether macrophages interacting with epithelial cells equally induce the EMT process in normal and eutopic endometria of healthy and adenomyotic patients; and whether macrophages parallelly polarize to M2. We investigated the expression levels of epithelial cadherin (E-cadherin), neural cadherin (N-cadherin), cytokeratin7 (CK7), vimentin, transforming growth factor-β1 (TGFB1), SMAD3 and pSMAD3 using immunohistochemistry and western blot, and then estimated the genetic levels of CD163, IL10 and MMP12 using real-time quantitative polymerase chain reaction (RT-PCR) in macrophages. Eutopic and normal endometrial tissues were obtained from 20 patients with adenomyosis and 11 control patients without adenomyosis, respectively. The immunohistochemical analysis shows distinct EMT in eutopic endometria in secretory phase; the expression levels of TGFB1, SMAD3 and pSMAD3 that indicate signal pathway of EMT were also higher in secretory phase. Macrophages can induce EMT process in primary endometrial epithelial cells derived from normal and eutopic endometria. After co-culturing, THP-1-derived macrophages polarized to M2. Compared with the eutopic endometrium group, further polarization to M2 was observed in the normal endometrium group. These results indicate that adenomyosis may be promoted by the pathologic EMT of epithelial cells, which is induced by macrophages that incapably polarize to M2.

Urocortin and corticotrophin-releasing hormone receptor type 2 mRNA are highly expressed in deep infiltrating endometriotic lesions

Ovarian endometrioma (OMA) and deep infiltrating endometriosis (DIE) are the most severe forms of endometriosis, but different pathogenetic mechanisms and clinical symptoms distinguish these two forms. Corticotrophin-releasing hormone (CRH) and urocortin (Ucn) are endometrial neuropeptides involved in tissue differentiation and inflammation. The expression of CRH, Ucn, Ucn2, CRH-receptors (type-1 and type-2) and inflammatory enzymes phospholipase-A2 group IIA (PLA2G2A) and cycloxygenase-2 (COX2) were evaluated in OMA (n = 22) and DIE (n = 26). The effect of CRH or Ucn on COX2 mRNA expression was evaluated in cultured human endometrial stromal cells. In DIE lesions, CRH, Ucn and CRH-R2 mRNA levels were significantly higher than in OMA (P < 0.01, P < 0.001 and P < 0.05, respectively); DIE lesions showed a higher expression of COX2 (P < 0.01) and PLA2G2A (P < 0.05) mRNA than OMA, which was positively correlated with CRH-R2 mRNA expression (P < 0.05). Intense immunostaining for CRH and Ucn was shown in DIE. Treatment of cultured endometrial stromal cells with Ucn significantly increased COX2 mRNA expression (P < 0.01); this effect was reversed by the CRH-R2 antagonist astressin-2B. In DIE, DIE lesions highly express neuropeptide and enzyme mRNAs, supporting a strong activation of inflammatory pathways.

Elevated expression of Nodal and YAP1 is associated with poor prognosis of gastric adenocarcinoma

PURPOSE

To investigate the correlation between Nodal and YAP1 expression and the clinicopathological characteristics of gastric adenocarcinoma (GAC).

METHODS

Quantitative real-time RT-PCR, Western blot, and immunohistochemistry were performed to measure Nodal and YAP1 mRNA and protein in 20 fresh frozen samples and 220 paraffin-embedded GAC tissues with their paired non-tumor mucosa (PNTM). The prognostic values of Nodal and YAP1 were evaluated in 161 GAC patients using univariate and multivariate analyses.

RESULTS

Both mRNA and protein expression of Nodal and YAP1 were significantly increased in GAC compared to PNTM (P < 0.05). Immunohistochemistry showed that Nodal was more highly expressed in 56.4 % GAC samples compared to PNTM; additionally, Nodal expression correlated with depth of tumor invasion, lymph node metastasis, and distant metastasis (all P < 0.05). There was no association between Nodal and YAP1 in GAC (P = 0.171). Kaplan-Meier analysis showed that the outcome of Nodal-high patients was significantly worse than those with low Nodal expression (χ (2) = 30.452, P < 0.001). Cox multivariate regression showed that high Nodal expression was an independent risk factor affecting the prognosis of GAC patients (P = 0.000, RR = 2.976). Furthermore, patients with tumors in which both Nodal and YAP1 were expressed at high levels had the worst prognosis.

CONCLUSIONS

Elevated Nodal expression is a marker of poor prognosis in gastric cancer. Patient outcome is further worsened if Nodal and YAP1 are both expressed in the same tumor. The datas we present here suggest that the inhibition of Nodal signaling may represent a new therapeutic strategy for the treatment of gastric adenocarcinoma.

Endometriosis Located Proximal to or Remote From the Uterus Differentially Affects Uterine Gene Expression

The mechanisms that lead to the altered uterine gene expression in women with endometriosis are poorly understood. Are these changes in gene expression mediated by proximity to endometriotic lesions or is endometriosis a systemic disease where the effect is independent of proximity to the uterus? To answer this question, we created endometriosis in a murine model either in the peritoneal cavity (proximal) or at a subcutaneous remote site (distal). The expression of several genes that are involved in endometrial receptivity (homeobox A10 [Hoxa10], homeobox A11 [Hoxa11], insulin-like growth factor binding protein 1 [Igfbp1], Kruppel-like factor 9 [Klf9], and progesterone receptor [Pgr]) was measured in the eutopic endometrium of mice transplanted with either proximal or distal endometriosis lesions. Decreased expression of Hoxa10, Igfbp1, Klf9, and total Pgr genes was observed in the eutopic endometrium of mice with peritoneal endometriosis. In the mice with distal lesions, overall expression of these genes was not as severely affected, however, Igfbp1 expression was similarly decreased and the effect on Pgr was more pronounced. Endometriosis does have a systemic effect that varies with distance to the end organ. However, even remote disease selectively and profoundly alters the expression of genes such as Pgr. This is the first controlled experiment demonstrating that endometriosis is not simply a local peritoneal disease. Selective alteration of genes critical for endometrial receptivity and endometriosis propagation may be systemic. Similarly, systemic effects of endometriosis on other organs may also be responsible for the widespread manifestations of the disease.