Regulation of A Disintegrin And Metalloproteinase with ThromboSpondin repeats-1 expression in human endometrial stromal cells by gonadal steroids involves progestins, androgens, and estrogens

Proteome-defined changes in cellular pathways for decidua and trophoblast tissues associated with location and viability of early-stage pregnancy

BACKGROUND

In early pregnancy, differentiating between a normal intrauterine pregnancy (IUP) and abnormal gestations including early pregnancy loss (EPL) or ectopic pregnancy (EP) is a major clinical challenge when ultrasound is not yet diagnostic. Clinical treatments for these outcomes are drastically different making early, accurate diagnosis imperative. Hence, a greater understanding of the biological mechanisms involved in these early pregnancy complications could lead to new molecular diagnostics.

METHODS

Trophoblast and endometrial tissue was collected from consenting women having an IUP (n = 4), EPL (n = 4), or EP (n = 2). Samples were analyzed by LC-MS/MS followed by a label-free proteomics analysis in an exploratory study. For each tissue type, pairwise comparisons of different pregnancy outcomes (EPL vs. IUP and EP vs. IUP) were performed, and protein changes having a fold change ≥ 3 and a Student's t-test p-value ≤ 0.05 were defined as significant. Pathway and network classification tools were used to group significantly changing proteins based on their functional similarities.

RESULTS

A total of 4792 and 4757 proteins were identified in decidua and trophoblast proteomes. For decidua, 125 protein levels (2.6% of the proteome) were significantly different between EP and IUP, whereas EPL and IUP decidua were more similar with only 68 (1.4%) differences. For trophoblasts, there were 66 (1.4%) differences between EPL and IUP. However, the largest group of 344 differences (7.2%) was observed between EP and IUP trophoblasts. In both tissues, proteins associated with ECM remodeling, cell adhesion and metabolic pathways showed decreases in EP specimens compared with IUP and EPL. In trophoblasts, EP showed elevation of inflammatory and immune response pathways.

CONCLUSIONS

Overall, differences between an EP and IUP are greater than the changes observed when comparing ongoing IUP and nonviable intrauterine pregnancies (EPL) in both decidua and trophoblast proteomes. Furthermore, differences between EP and IUP were much higher in the trophoblast than in the decidua. This observation is true for the total number of protein changes as well as the extent of changes in upstream regulators and related pathways. This suggests that biomarkers and mechanisms of trophoblast function may be the best predictors of early pregnancy location and viability.

ADAMTS-1: a novel target gene of an estrogen-induced transcription factor, EGR1, critical for embryo implantation in the mouse uterus

BACKGROUND

Recently, we demonstrated that estrogen (E₂) induces early growth response 1 (Egr1) to mediate its actions on the uterine epithelium by controlling progesterone receptor signaling for successful embryo implantation. EGR1 is a transcription factor that regulates the spectrum of target genes in many different tissues, including the uterus. E₂-induced EGR1 regulates a set of genes involved in epithelial cell remodeling during embryo implantation in the uterus. However, only few target genes of EGR1 in the uterus have been identified.

RESULT

The expression of ADAM metallopeptidase with thrombospondin type 1 motif 1 (Adamts-1) was significantly downregulated in the uteri of E₂-treated ovariectomized (OVX) Egr1(-/-) mice. Immunostaining of ADAMTS-1 revealed its exclusive expression in the uterine epithelium of OVX wild-type but not Egr1(-/-) mice treated with E₂. The expression profiles of Adamts-1 and Egr1 were similar in the uteri of E₂-treated OVX mice at various time points tested. Pre-treatment with ICI 182, 780, a nuclear estrogen receptor (ER) antagonist, effectively inhibited the E₂-dependent induction of Egr1 and Adamts-1. Pharmacologic inhibition of E₂-induced ERK1/2 or p38 phosphorylation interfered with the induction of EGR1 and ADAMTS-1. Furthermore, ADAMTS-1, as well as EGR1, was induced in stroma cells surrounding the implanting blastocyst during embryo implantation. Transient transfection with EGR1 expression vectors significantly induced the expression of ADAMTS-1. Luciferase activity of the Adamts-1 promoter containing EGR1 binding sites (EBSs) was increased by EGR1 in a dose-dependent manner, suggesting functional regulation of Adamts-1 transcription by EGR1. Site-directed mutagenesis of EBS on the Adamts-1 promoter demonstrated that EGR1 directly binds to the EBS at -1151/-1134 among four putative EBSs.

CONCLUSIONS

Collectively, we have demonstrated that Adamts-1 is a novel target gene of E₂-ER-MAPK-EGR1, which is critical for embryo implantation in the mouse uterus during early pregnancy.

Molecular characterization of PRM-associated endometrial changes, PAEC, following mifepristone treatment

OBJECTIVE

The progesterone receptor modulator (PRM) mifepristone holds the potential to be developed for regular contraception. However, long-term treatment can cause thickening of the endometrium and PRM-associated endometrial changes (PAEC). The objective of this study was to explore the molecular expression of endometrium displaying PAEC after mifepristone treatment in order to understand the future implications of PAEC and safety of long-term use.

STUDY DESIGN

Endometrial biopsies were obtained from premenopausal women following 3 months of continuous mifepristone treatment. The biopsies were evaluated regarding occurrence of PAEC and followed up by a comparative analysis of gene expression in PAEC endometrium (n=7) with endometrium not displaying PAEC (n=4). Methods used included microarray analysis, Ingenuity Pathway Analysis (IPA) and real-time polymerase chain reaction.

RESULTS

Three genes relevant within endometrial function were up-regulated with PAEC: THY1 (p=.02), ADAM12 (p=.04) and TN-C (p=.04). The proliferation marker MKi67 was not altered (p=.31). None of the differentially regulated genes were involved in the endometrial cancer-signaling pathway (based on IPA knowledge database).

CONCLUSION

The genes altered in endometrium displaying PAEC after 3 months of mifepristone exposure are mainly involved in the structural architecture of tissue.

IMPLICATIONS

PAEC features may be explained by the altered genes and their networks affecting tissue architecture although not involved in endometrial cancer signaling pathways, and thus, treatment with mifepristone at this dosage does not show any adverse effect at endometrial level.

Adamts 1, 4, 5, 8, and 9 in Early Pregnancies

INTRODUCTION

The aim of this study was to immunohistochemically investigate the presence and localization of ADAMTS 1, 4, 5, 8 and 9 in decidual and chorionic tissues in first trimester pregnancy losses.

MATERIALS AND METHODS

This study was conducted with early pregnancy failure decidual and chorionic tissue samples from 36 pregnant women in the first trimester of pregnancy (ongoing pregnancies, missed miscarriages, anembryonic pregnancies) Results: It was observed that the decidual and chorionic tissue levels of ADAMTS 1, 4, 5, and 8 in ongoing pregnancies were more intensely expressed when compared with miscarriages. ADAMTS 1 expression was not observed in the anembryonic pregnancies, ADAMTS 4, 5, and 8 were less intensely expressed. ADAMTS 9 showed no staining in any group.

CONCLUSION

ADAMTS 1 may be necessary during the decidualization and implantation stages of early normal pregnancy.

ADAMTS-1 Is Found in the Nuclei of Normal and Tumoral Breast Cells

Proteins secreted in the extracellular matrix microenvironment (ECM) by tumor cells are involved in cell adhesion, motility, intercellular communication and invasion. The tumor microenvironment is expansively modified and remodeled by proteases, resulting in important changes in both cell-cell and cell-ECM interactions and in the generation of new signals from the cell surface. Metalloproteinases belonging to the ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs) family have been implicated in tissue remodeling events observed in cancer development, growth and progression. Here we investigated the subcellular localization of ADAMTS-1 in normal-like (MCF10-A) and tumoral (MCF7 and MDA-MB-231) human breast cells. ADAMTS-1 is a secreted protease found in the extracellular matrix. However, in this study we show for the first time that ADAMTS-1 is also present in the nuclei and nucleoli of the three mammary cell lines studied here. Our findings indicate that ADAMTS-1 has proteolytic functions in the nucleus through its interaction with aggrecan substrate.

Regulation of Androgen Receptor Expression Alters AMPK Phosphorylation in the Endometrium: In Vivo and In Vitro Studies in Women with Polycystic Ovary Syndrome

The failure of reproductive success in polycystic ovary syndrome (PCOS) patients could be in part due to endometrial dysfunction. However, no studies have investigated any causality between androgen, androgen receptor (AR) expression, and adenosine monophosphate activated protein kinase (AMPK) activation in the endometrium under physiological and pathological conditions. In the present study, we show that 1) endometrial AR expression levels fluctuate in non-PCOS and PCOS patients during the menstrual cycle; 2) the menstrual phase-dependent alteration of p-AMPKα expression occurs in non-PCOS patients but not in PCOS patients; 3) AR expression is higher in PCOS patients than non-PCOS patients during hyperplasia while AMPKα activation (indicated by the ratio of p-AMPKα to AMPKα); and 4) co-localization of AR and Ki-67 in epithelial cell nuclei is observed in endometrial hyperplasia. Importantly, using in vitro human tissue culture and an in vivo 5α-dihydrotestosterone-treated rat model, we show that the action of androgen on AMPKα activation is likely mediated through nuclear AR, especially in epithelial cells. Collectively, we present evidence that AR expression and AMPKα activation depend on menstrual cycle phase and the presence of PCOS, and the data suggest that AR-mediated regulation of AMPKα activation might play a role in the development of endometrial hyperplasia.

ADAMTS proteases in fertility

The reproductive organs are unique among adult organs in that they must undergo continual tissue remodelling as a key aspect of their normal function. The processes for persistent maturation and release of new gametes, as well as fertilisation, implantation, placentation, gestation and parturition involve cyclic development and regression of tissues that must continually regenerate to support fertility. The ADAMTS family of proteases has been shown to contribute to many aspects of the tissue morphogenesis required for development and function of each of the reproductive organs. Dysregulation or functional changes in ADAMTS family proteases have been associated with reproductive disorders such as polycystic ovarian syndrome (PCOS) and premature ovarian failure (POF). Likewise, proteolytic substrates of ADAMTS enzymes have also been linked to reproductive function. New insight into the roles of ADAMTS proteases has yielded a deeper understanding of the molecular mechanisms behind fertility with clinical potential to generate therapeutic targets to resolve infertility, develop biomarkers that predict dysfunction of the reproductive organs and potentially offer targets for development of non-hormonal male and female contraceptives.

A new biological marker candidate in female reproductive system diseases: Matrix metalloproteinase with thrombospondin motifs (ADAMTS)

Playing a key role in the pathophysiology of many diseases, A Disintegrin-like and Metalloproteinase with Thrombospondin type-1 motif (ADAMTS) proteinases have been attracted more attention in obstetrics and gynecology. First discovered in 1997, this zinc-dependent proteinase family has 19 members today. These enzymes, which are located in the extracellular matrix (ECM), have a lot of very important functions, like matrix formation and resorption, angiogenesis, ovulation, and coagulation. In addition, in the pathogenesis of cancer, inflammation, arthritis, and connective tissue diseases, ADAMTS proteinases have crucial roles. The purpose of this review is to collect previous studies about obstetrics and gynecology that are related to ADAMTS enzymes and discuss the subject in many aspects to give an idea to the investigators who are interested in the subject.

Gonadal steroids regulate the expression of aggrecanases in human endometrial stromal cells in vitro

The human endometrium undergoes cyclic change during each menstrual cycle in response to gonadal steroids. Proteolysis of endometrial extracellular matrix (ECM) is necessary to prepare this dynamic tissue for pregnancy. Proteolytic enzymes such as matrix metalloproteinase (MMP) and closely related a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been assigned key roles in the highly regulated cyclic remodelling of the endometrial ECM. We have previously shown that ADAMTS-1 undergoes spatiotemporal changes in human endometrial stromal cells under the regulation of gonadal steroids. This suggests that other ADAMTS subtypes, known as aggrecanases, may contribute to the ECM remodelling events that occur in female physiological cycles and in preparation for pregnancy. To determine whether progesterone (P4), 17β-estradiol (E2), or dihydrotestosterone (DHT), alone or in combination, are capable of regulating ADAMTS-4, -5, -8 or -9 expression in human endometrial stromal cells in vitro. Real-time quantitative PCR and Western blot analysis were used to measure ADAMTSs mRNA and protein levels in primary cultures of human endometrial stromal cells (n = 12). P4, DHT but not E2 have regulatory effects on ADAMTS-8, -9 and -5 expression. Combined treatment with gonadal steroids did not show any synergistic or antagonistic effects. However, the synthetic steroid antagonists RU486 and hydroxyflutamide specifically inhibited the P4- or DHT-mediated regulatory effects on ADAMTS expression. These studies provide evidence that the regulation of aggrecanases by gonadal steroids in human endometrial stromal cells may play an important role during decidualization.

Expression of ADAMTS1 mRNA in bovine endometrium and placenta during gestation

A disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS1) is a secreted protease. Through the regulation of extracellular matrix remodeling or developmental processes or both, ADAMTS1 is involved in several biological functions, including ovulation and embryo receptivity. However, the expression and possible role of ADAMTS1 in bovine endometrium is unknown. In this study, we analyzed ADAMTS1 mRNA expression in bovine endometrium during the estrous cycle, peri-implantation period, and at different stages of gestation by using quantitative real-time RT-PCR (qPCR) and in situ hybridization. The qPCR results indicated that the expression of ADAMTS1 mRNA was not affected by the day of the estrous cycle and was similar to cyclic levels on day 35 of gestation; however, the expression was more abundant in cotyledonary tissues of the placenta during late gestation. The in situ hybridization study showed that ADAMTS1 mRNA was detected mainly in uterine luminal epithelia and stromal cells during the estrous cycle and peri-implantation period. A disintegrin and metalloproteinase with thrombospondin motifs 1 mRNA was also expressed in the peri-implantation conceptus as well as in trophoblast cells, which include binucleate cells, and increased during late gestation. Furthermore, treatment of stromal cell with progesterone (300 nM) stimulated the expression of ADAMTS1 mRNA. This study indicates that ADAMTS1 participates in bovine endometrial remodeling, which is required for implantation and placental development in coordination with ovarian steroids.

Progesterone interactions with the cervix: translational implications for term and preterm birth

The uterine cervix plays a vital role in maintaining pregnancy and an equally important role in allowing parturition to occur. Progesterone, either endogenously produced or supplied exogenously, supports the function of the cervix in sustaining intrauterine pregnancy, and the withdrawal of progesterone, either through natural processes or pharmacologic intervention, leads to delivery which underscores the importance of the progesterone's biological activities manifest in normal gestation and pregnancy that ends prematurely. Research crossing many scientific disciplines has demonstrated that progesterone is a pleotropic compound that affects the cervix through cytoplasmic and membrane receptors with profound effects on cellular and molecular functions that influence inflammatory cascades and extracellular matrix, both of which have consequences for parturition. Beyond the local cell and molecular biology of progesterone, it has systemic effects of relevance to pregnancy as well. This paper examines the biology of the cervix from its gross to cellular structure and biological activities of its cell and molecular processes that may be affected by progesterone. The implications of these processes for preterm birth are explored, and direction of current research is in relation to translational medicine implications for diagnostic, prognostic, and therapeutic approaches to threatened preterm birth.

Altered expression of genes regulating angiogenesis in experimental androgen-independent prostate cancer

BACKGROUND

The aim of this study was to investigate how the expression of genes regulating angiogenesis is altered when prostate cancer cells progress into androgen-independency.

METHODS

A gene array specific for angiogenesis was used to compare the human prostate cancer cell line LNCaP (androgen-dependent) with its more angiogenic and tumorigenic subline LNCaP-19 (androgen-independent). Results were verified with real-time RT-PCR, and further investigations were focused on the angiogenesis inhibitor a disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS1). Expression of ADAMTS1 was investigated in vitro as well as in subcutaneous tumors with real-time RT-PCR and Western blotting. Microvessel density (MVD), versican proteolysis and protein levels of TIMP-2 and TIMP-3, known as ADAMTS1 inhibitors, were also analyzed in tumor xenografts.

RESULTS

The gene array revealed decreased expression of ADAMTS1, ephrin-A5, fibronectin 1, and neuropilin 1 in LNCaP-19 compared to LNCaP, while expression of midkine and VEGF were increased. Further studies showed that mRNA and protein levels of ADAMTS1 were significantly lower in LNCaP-19 compared to LNCaP, both in vitro and in subcutaneous tumors. The amount of ADAMTS1 correlated negatively with MVD, but no relation was found between ADAMTS1 and versican proteolysis.

CONCLUSIONS

Expression of several genes associated with angiogenesis was altered during transition into androgen-independency. Among these, a significant decrease was found for ADAMTS1, whose expression inversely correlated with MVD. Its role in progression of prostate cancer needs further investigation, but this inhibitor of angiogenesis could be an interesting candidate for future anti-angiogenic therapy.