N-cadherin knockdown leads to disruption of trophoblastic and endothelial cell interaction in a 3D cell culture model - New insights in trophoblast invasion failure

Regulators involved in trophoblast syncytialization in the placenta of intrauterine growth restriction

Placental dysfunction refers to the insufficiency of placental perfusion and chronic hypoxia during early pregnancy, which impairs placental function and causes inadequate supply of oxygen and nutrients to the fetus, affecting fetal development and health. Fetal intrauterine growth restriction, one of the most common outcomes of pregnancy-induced hypertensions, can be caused by placental dysfunction, resulting from deficient trophoblast syncytialization, inadequate trophoblast invasion and impaired vascular remodeling. During placental development, cytotrophoblasts fuse to form a multinucleated syncytia barrier, which supplies oxygen and nutrients to meet the metabolic demands for fetal growth. A reduction in the cell fusion index and the number of nuclei in the syncytiotrophoblast are found in the placentas of pregnancies complicated by IUGR, suggesting that the occurrence of IUGR may be related to inadequate trophoblast syncytialization. During the multiple processes of trophoblasts syncytialization, specific proteins and several signaling pathways are involved in coordinating these events and regulating placental function. In addition, epigenetic modifications, cell metabolism, senescence, and autophagy are also involved. Study findings have indicated several abnormally expressed syncytialization-related proteins and signaling pathways in the placentas of pregnancies complicated by IUGR, suggesting that these elements may play a crucial role in the occurrence of IUGR. In this review, we discuss the regulators of trophoblast syncytialization and their abnormal expression in the placentas of pregnancies complicated by IUGR.

Leveraging bioengineering to assess cellular functions and communication within human fetal membranes

The fetal membranes enclose the growing fetus and amniotic fluid. Preterm prelabor rupture of fetal membranes is a leading cause of preterm birth. Fetal membranes are composed of many different cell types, both structural and immune. These cells must coordinate functions for tensile strength and membrane integrity to contain the growing fetus and amniotic fluid. They must also balance immune responses to pathogens with maintaining maternal-fetal tolerance. Perturbation of this equilibrium can lead to preterm premature rupture of membranes without labor. In this review, we describe the formation of the fetal membranes to orient the reader, discuss some of the common forms of communication between the cell types of the fetal membranes, and delve into the methods used to tease apart this paracrine signaling within the membranes, including emerging technologies such as organ-on-chip models of membrane immunobiology.

PETN-Induced Antioxidative Properties in Endothelial Cells as a Target for Secondary Prevention of Endothelial Dysfunction in Pregnancy

The NO-donor Pentaerytrithyltetranitrate (PETN) has vasodilatative properties and direct protective effects on endothelial cells. We formerly demonstrated that PETN, given to pregnant women during the second and third trimester, influences endothelial dysfunction related pregnancy complications like preeclampsia (PE) and fetal growth restriction (FGR). PETN treatment showed to delay PE to late pregnancy and achieved a profound risk reduction for FGR and/or perinatal death of 40%. The aim of this study was to confirm the effect of PETN on endothelial cell dysfunction at molecular level in an experimental approach. To induce endothelial dysfunction HUVEC were treated with 10 U/l of thrombin in the presence or absence of PETN. qRT-PCR analysis showed that PETN induced the expression of heme-oxygenase-1 and superoxide dismutase two but not endothelial NO-synthase under basal conditions. The induction of antioxidant proteins did not change basal reactive oxygen species (ROS) levels as measured by MitoSOX™ staining. PETN treatment significantly delayed the thrombin-induced disruption of the endothelial monolayer, determined using the xCELLigence^® and attenuated the disrupting effect of thrombin on tubular junctions as seen in a tube-forming assay on Matrigel™. In western-blot-analysis we could show that PETN significantly reduced thrombin-induced extracellular signal-regulated kinase activation which correlates with reduction of thrombin-induced ROS. These experimental results establish the concept of how PETN treatment could stabilize endothelial resistance and angiogenic properties in pregnancy-induced stress. Thus, our results underscore the assumption, that the shown clinical effects of PETN are associated to its endothelial cell protection.

The role of junctional adhesion molecule-C in trophoblast differentiation and function during normal pregnancy and preeclampsia

INTRODUCTION

Junctional adhesion molecule-C (JAM-C) is an important regulator of many physiological processes, ranging from maintenance of tight junction integrity of epithelia to regulation of cell migration, homing and proliferation. Preeclampsia (PE) is a trophoblast-related syndrome with abnormal placentation and insufficient trophoblast invasion. However, the role of JAM-C in normal pregnancy and PE pathogenesis is unknown.

METHODS

The expression and location of JAM-C in placentas were determined by quantitative real-time PCR (qRT-PCR), western blot and immunohistochemistry. The expression of differentiation and invasion markers were detected by qRT-PCR or western blot. The effects of JAM-C on migration and invasion of trophoblasts were examined using wound-healing and invasion assays. Additionally, a mouse model was established by injection of JAM-C-positive adenovirus to explore the effects of JAM-C in vivo.

RESULTS

In normal pregnancy, JAM-C was preferentially expressed on cytotrophoblast (CTB) progenitors and progressively decreased when acquiring invasion properties with gestation advance. However, in PE patients, the expression of JAM-C was upregulated in extravillous trophoblasts (EVTs) and syncytiotrophoblasts (SynTs) of placentas. It was also demonstrated that JAM-C suppressed the differentiation of CTBs into EVTs in vitro. Consistently, JAM-C inhibited the migration and invasion capacities of EVTs through GSK3β/β-catenin signaling pathway. Importantly, Ad-JAMC-infected mouse model mimicked the phenotype of human PE.

DISCUSSION

JAM-C plays an important role in normal placentation and upregulated JAM-C in placentas contributes to PE development.

Epithelial-mesenchymal transition process during embryo implantation

The epithelial to mesenchymal transition (EMT) in endometrial epithelial and trophectoderm cells is essential for the progression of embryo implantation and its impairment could cause implantation failure. Therefore, EMT should be tightly regulated in both embryonic and endometrial cells during implantation. Studies reported the involvement of numerous factors in EMT regulation, including hormones, growth factors, transcription factors, microRNAs, aquaporins (AQPs), and ion channels. These factors act through different signaling pathways to affect the expression of epithelial and mesenchymal markers as well as the cellular cytoskeleton. Although the mechanisms involved in cancer cell EMT have been well studied, little is known about EMT during embryo implantation. Therefore, we comprehensively reviewed different factors that regulate the EMT, a key event required for the conceptus implantation to the endometrium.Summary sentence: Abnormal epithelial-mesenchymal transition (EMT) process within endometrial epithelial cells (EECs) or trophoblast cells can cause implantation failure. This process is regulated by various factors. Thus, the objective of this review was to summarize the effective factors on the EMT process during implantation.

Role of clusterin in the regulation of trophoblast development and preeclampsia

Preeclampsia (PE) threatens the safety of mothers and fetuses, and its pathogenesis is still unclear. Our previous study has found the relationship between PE and serum Clusterin (CLU). This study aimed to investigate the role of CLU on PE. Firstly, levels of CLU in serum and placental tissue from PE patients and healthy pregnancies were compared. Then, RNA sequencing, cell counting kit-8, matrigel invasion, cell apoptosis, and angiogenesis assay were performed to evaluate the role of CLU on primary isolation trophoblast cells. We found the expression of CLU was increased before the clinical syndrome occurred, whereas its level was positively related to the severity of PE. CLU significantly inhibited the expression of matrix metalloproteinase-9 and Vimentin and enhanced E-cadherin to inhibit epithelial-mesenchymal transition of trophoblast cells, further reducing its migration and invasion. Our results suggested that CLU may play a role in regulating trophoblast invasion and migration during placental development, which may be one of the risk factors for PE.

Congenital Transmission of Apicomplexan Parasites: A Review

Apicomplexans are a group of pathogenic protists that cause various diseases in humans and animals that cause economic losses worldwide. These unicellular eukaryotes are characterized by having a complex life cycle and the ability to evade the immune system of their host organism. Infections caused by some of these parasites affect millions of pregnant women worldwide, leading to various adverse maternal and fetal/placental effects. Unfortunately, the exact pathogenesis of congenital apicomplexan diseases is far from being understood, including the mechanisms of how they cross the placental barrier. In this review, we highlight important aspects of the diseases caused by species of Plasmodium, Babesia, Toxoplasma, and Neospora, their infection during pregnancy, emphasizing the possible role played by the placenta in the host-pathogen interaction.

Sticking together: Harnessing cadherin biology for tissue engineering

Directing cell behavior and building a tissue for therapeutic impact is the main goal of regenerative medicine, for which scientists need to modulate the interaction of cells with biomaterials. The focus of the field thus far has been on the incorporation of cues from the extracellular matrix but we propose that scientists take lessons from cell-cell adhesion proteins, more specifically cadherin biology, as these proteins make multicellularity possible. In this perspective, we re-examine cadherins through the lens of a tissue engineer for the purpose of advancing regenerative medicine. Furthermore, we summarize exciting developments in biomaterials inspired by cadherins and discuss some challenges and opportunities for the future. STATEMENT OF SIGNIFICANCE: Tissue engineers need tools to direct cell behavior. To date, tissue engineers have designed many sophisticated materials to positively influence cell behavior but are faced with the challenge where these materials sometimes work and sometimes fail. This uncertainty is a big unanswered question that challenges the community. We propose that tissue engineering could be more successful if they would take lessons from cell-cell adhesion proteins, more specifically cadherin biology. In the article, we discuss key structural and functional characteristics that make cadherins ideal for tissue engineering approaches. Furthermore, by providing a state-of-the-art overview of exemplary studies that have used cadherins to influence cell behavior, we show tissue engineers that they already have the tools necessary to incorporate this knowledge.

Iodothyronine deiodinase 2 (DiO2) regulates trophoblast cell line cycle, invasion and apoptosis; and its downregulation is associated with early recurrent miscarriage

INTRODUCTION

Trophoblast development is a crucial event in placentation and pregnancy complications but its underlying mechanisms remain unclear. Thus, we aimed at investigating the role of DiO2 in trophoblast cell line decisions and assessing its placental villous expression in early recurrent miscarriage (ERM) patients.

METHODS

The placental villous expression of DiO2 was determined with immunofluorescence. Cell proliferation was measured with the CCK8 kit while cell-cycle and apoptosis were studied with flow-cytometry. Cell migration and invasion were measured with wound-healing and transwell assays, respectively. Gene expression was then assessed with RT-qPCR and western blotting.

RESULTS

DiO2 is expressed in the CTB, PCT, DCT and STB of the placenta. Its overexpression arrested trophoblast cell line proliferation at the G1 phase of the cell-cycle by downregulating cyclin-D1 and PCNA, while promoting apoptosis via increased caspase-3 activity and inhibition of the AKT and ERK1/2 signaling pathways. Also, it augmented trophoblast cell line migration and invasion via the upregulation of N-cadherin, vimentin, fascin-1, twist-1 and other epithelial-mesenchymal transition genes. DiO2 knockdown elicited the opposite effects. Surprisingly, each of these effects of DiO2 manipulation was not mediated by thyroid hormone metabolism. Assessment of the ERM placental villi revealed a downregulation of DiO2, N-cadherin, vimentin, fascin-1 and twist-1. The expression of E-cadherin remained unchanged in these placentae.

DISCUSSION

During placentation, DiO2 may inhibit trophoblast proliferation while facilitating their differentiation into an invasive phenotype; and that its downregulation may contribute to the shallow trophoblast invasion that precedes ERM. Hence, DiO2 is a potential therapeutic target against ERM.

Bioengineered Microphysiological Placental Models: Towards Improving Understanding of Pregnancy Health and Disease

Driven by a lack of appropriate human placenta models, recent years have seen the introduction of bioengineered in vitro models to better understand placental health and disease. Thus far, the focus has been on the maternal-foetal barrier. However, there are many other physiologically and pathologically significant aspects of the placenta that would benefit from state-of-the-art bioengineered models, in particular, integrating advanced culture systems with contemporary biological concepts such as organoids. This critical review defines and discusses the key parameters required for the development of physiologically relevant in vitro models of the placenta. Specifically, it highlights the importance of cell type, mechanical forces, and culture microenvironment towards the use of physiologically relevant models to improve the understanding of human placental function and dysfunction.

Effect of lncRNA-ATB/miR-651-3p/Yin Yang 1 pathway on trophoblast-endothelial cell interaction networks

Our previous studies have confirmed that lncRNA‐ATB may be involved in the pathogenesis of preeclampsia, however, it is uncertain whether lncRNA‐ATB influence the interaction between trophoblast and endothelial cells, which is crucial to the uterine spiral artery remodelling. Scratch wound healing and transwell invasion assay were conducted to test the migration and invasion of trophoblast cells. Co‐culture model was used to simulate the physiological environment in vivo. The expression levels of lncRNA‐ATB were analyzed in placenta tissues from healthy pregnant women and preeclampsia patients. Subsequently, the binding site of lncRNA‐ATB and miR‐651‐3p was verified using dual‐luciferase reporter assay, and the rescue experiment was used to study the effects of these two on the biological function. The direct effects of miR‐651‐3p and Yin Yang 1 (YY1) were verified using similar methods. LncRNA‐ATB was found to be down‐regulated in the placenta of preeclampsia patients. LncRNA‐ATB knockdown decreased trophoblast migration, invasion and colocalisation with human umbilical vein endothelial cells. MiR‐651‐3p was a direct target of lncRNA‐ATB and they had opposite effects. Moreover, the expression of lncRNA‐ATB and miR‐651‐3p in placental tissues was negatively correlated. MiR‐651‐3p has been confirmed to directly target the 3′ untranslated region of YY1. The inhibitory effects of YY1 low expression on biological function was rescued by miR‐651‐3p depletion. Western blot analysis showed that lncRNA‐ATB could regulate YY1 expression by sponging miR‐651‐3p. LncRNA‐ATB functioned as a competitive endogenous RNA of miR‐651‐3p to regulate YY1 on progress of spiral artery remodelling.

Galectin-14 Promotes Trophoblast Migration and Invasion by Upregulating the Expression of MMP-9 and N-Cadherin

Galectin-14 is specifically expressed in placental trophoblasts, and its expression is reduced in trophoblasts retrieved from the cervix of women destined to develop early pregnancy loss. However, the roles of galectin-14 in regulating trophoblasts and in the pathogenesis of pregnancy complication have never been investigated. In the current research, we aimed to investigate the roles of galectin-14 in the regulation of trophoblasts. Tissues of the placenta and villi were collected. Primary trophoblasts and human trophoblast cell line HTR-8/SVneo were used. Western blotting and RT-PCR were used to quantify gene expression. The siRNA-mediated galectin-14 knockdown and lentivirus-mediated overexpression were performed to manipulate the gene expression in trophoblasts. Transwell migration and invasion assays were used to evaluate cell migration and invasion capacity. Gelatin zymography was used to determine the gelatinase activity. Galectin-14 was significantly decreased in the villi of early pregnancy loss and the placenta of preeclampsia. Knockdown of galectin-14 in primary trophoblasts inhibited cell migration and invasion, downregulated the expression of matrix metalloproteinase (MMP)-9 and N-cadherin, the activity of MMP-9, and decreased the phosphorylation of Akt. Meanwhile, the overexpression of galectin-14 in HTR-8/SVneo promoted cell migration and invasion, upregulated the expression of MMP-9 and N-cadherin, the activity of MMP-9, and increased the phosphorylation of Akt. Increased Akt phosphorylation promoted cell migration and invasion and upregulated the expression and activity of MMP-9, while decreased Akt phosphorylation inhibited cell migration and invasion and downregulated the expression and activity of MMP-9. Thus, galectin-14 promotes trophoblast migration and invasion by enhancing the expression of MMP-9 and N-cadherin through Akt phosphorylation. The dysregulation of galectin-14 is involved in the pathogenesis of early pregnancy loss and preeclampsia.

Molecular characteristics of established trophoblast-derived cell lines

INTRODUCTION

Research on human placental development and function lacks a conclusive in vivo model. To investigate the intracellular molecular mechanisms in trophoblast cells, different cell lines have been established during the last decades. So far, none of these accomplishes all features of primary trophoblast, thus their suitability as well as the transferability of the results has been discussed. The aim of this study is to assess molecular markers and features matching different trophoblast subpopulations in trophoblastic cell lines to provide orientation on their suitability and relevance for distinct research questions.

METHODS

The commonly used trophoblastic cell lines, BeWo, JEG-3, HTR-8/SVneo, AC1-M59, AC1-M32, ACH-3P and Swan71 were selected. qPCR and immunoblotting were used to determine expression of characteristic molecular markers. C14MC, C19MC and miR-371-3 miRNA expression were investigated by real time PCR. Proliferation, migration and network stabilization assays were performed. Hormone secretion was determined by chemiluminescent-immunoassays. DNA profiles were obtained by Short Tandem Repeat (STR)-genotyping.

RESULTS

Immortalized cell lines differ from choriocarcinoma-derived ones in the expression of HLA-G, E-cadherin, N-cadherin, VE-cadherin, cadherin-11, cytokeratin 7, vimentin, ADAM12 and PRG2. Compared to choriocarcinoma-derived cell lines, expression of C19MC and hormone secretion were almost absent in immortalized cell lines. Conversely, they express C14MC and exhibit higher migration and network stabilization.

DISCUSSION

The data presented will help justify the use of a cell line to evaluate distinct features of trophoblast biology and pathology. In general, characteristics and markers of choriocarcinoma derived cell lines seem to be more similar to in vivo trophoblast than immortalized cell lines and thus might be regarded as more suitable models.

Macrophage migration inhibitory factor in human early pregnancy events and association with placental pathologies

Macrophage migration inhibitory factor (MIF) is a versatile cytokine acting as an important regulator of innate and adaptive immunity and implicated in many physiological and pathological processes. It is abundantly expressed at the feto-maternal interface and proposed to have a role in establishing and maintaining a healthy pregnancy. This review presents the current literature data regarding the MIF role in early pregnancy events and its association with some of the placental pathological conditions, including infection, preeclampsia, gestational diabetes mellitus and choriocarcinoma. General information regarding MIF structure and function is followed by an overview of its expression in reproductive tissues and in pregnancy. Futher, we discuss MIF's involvement in the survival of decidual stromal cells, placenta of the first trimester of pregnancy, and in trophoblast cell functions studied in vitro. Current findings associating this cytokine to placental infection, preeclampsia, gestational diabetes mellitus and choriocarcinoma are presented in the final part.

The Involvement of Cell Adhesion Molecules, Tight Junctions, and Gap Junctions in Human Placentation

Placentation is a major determinant of the success of pregnancy. It is regulated by several factors such as cell adhesion molecules, tight junctions, and gap junctions. The cell adhesion molecules are integrins, cadherins, immunoglobulins, nectins, and selectins. The tight junctions are composed of claudins, occludin, and junction adhesion molecule proteins while the gap junctions are composed of connexins of varying molecular weights. During placentation, some of these molecules regulate trophoblast proliferation, trophoblast fusion, trophoblast migration, trophoblast invasion, trophoblast-endothelium adhesion, glandular remodeling, and spiral artery remodeling. There is a dysregulated placental expression of some of these molecules during obstetric complications. We have, hereby, indicated the expression patterns of the subunits of each of these molecules in the various trophoblast subtypes and in the decidua, and have highlighted their involvement in physiological and pathological placentation. The available evidence points to the relevance of these molecules as distinguishing markers of the various trophoblast lineages and as potential therapeutic targets in the management of malplacentation-mediated diseases.

Involvement of WNT2 in trophoblast cell behavior in preeclampsia development

This study aimed to determine the WNT2 expression in patients with severe preeclampsia and to explore the function of WNT2 dysregulation on the biological behaviors of trophoblast cells. The WNT2 and β-catenin expression in the patients with early-onset and late-onset severe preeclampsia and normal controls was determined. Subsequently, WNT2 was overexpressed and knocked down in HTR8 cells and WNT2 signaling pathway in regulating trophoblast cell proliferation, migration, invasion, and apoptosis were evaluated in vitro. The mRNA and protein expression levels of WNT2 and β-catenin were decreased in patients with preeclampsia, especially early-onset severe preeclampsia. Overexpression of WNT2 promoted trophoblast cell proliferation, migration, and invasion and inhibited apoptosis in vitro, whereas knockdown of WNT2 had opposite effects. The findings of this study reveal that WNT2 and β-catenin were decreased expressed in patients with preeclampsia. Decreased expression of WNT2 may inhibit trophoblast cell proliferation, migration, and invasion but induced apoptosis. WNT2 may serve as a promising biomarker for early detection of preeclampsia.

Deficiency of DICER reduces the invasion ability of trophoblasts and impairs the pro-angiogenic effect of trophoblast-derived microvesicles

DICER is a key rate‐limiting enzyme in the canonical miRNAs biogenesis pathway, and DICER and DICER‐dependent miRNAs have been proved to play essential roles in many physiological and pathological processes. However, whether DICER is involved in placentation has not been studied. Successful spiral artery remodelling is one of the key milestones during placentation, which depends mostly on the invasion of trophoblasts and the crosstalk between trophoblasts and endothelial cells. In the present study, we show that DICER knockdown impairs the invasion ability of both primary extravillous trophoblasts (EVT) and HTR8/SVneo (HTR8) cell lines. The decreased invasion of HTR8 cells upon DICER knockdown (sh‐Dicer) was partly due to the up‐regulation of miR‐16‐2‐3p, which led to a reduced expression level of the collagen type 1 alpha 2 chain (COL1A2) protein. Moreover, microvesicles (MVs) can be secreted by HTR8 cells and promote the tube formation ability of human umbilical cord vein endothelial cells (HUVECs). However, conditioned medium and MVs derived from sh‐Dicer HTR8 cells have an anti‐angiogenic effect, due to reduced angiogenic factors and increased anti‐angiogenic miRNAs (including let‐7d, miR‐1‐6‐2 and miR‐15b), respectively. In addition, reduced protein expression of DICER is found in PE placenta by immunoblotting and immunohistochemistry. In summary, our study uncovered a novel DICER‐miR‐16‐2‐COL1A2 mediated pathway involved in the invasion ability of EVT, and DICER‐containing MVs mediate the pro‐angiogenic effect of trophoblast‐derived conditioned medium on angiogenesis, implying the involvement of DICER in the pathogenesis of PE.

Macrophage migration inhibitory factor is involved in endovascular trophoblast cell function in vitro

Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine abundantly present at the feto-maternal interface proposed to play a role in establishment of pregnancy. We have previously shown that pharmacological inhibition of enzymatic activity of MIF decreases extravillous trophoblast invasion and migration in vitro. This study aimed to further elucidate potential role of endogenous trophoblast MIF, and to assess its importance for endovascular trophoblast cell function in particular. Attenuation of MIF by siRNA reduced HTR-8/SVneo cell invasion through Matrigel (59 % of control), expression of integrin α₁ (86 % of control) and levels of MMP2 and MMP9 (87 % and 57 % of control, respectively). MIF specific siRNA reduced the ability of HTR-8/SVneo to differentiate in to endothelial-like phenotype, as determined by Matrigel tube formation assay. The total tube length was decreased to 68.6 %, while the number of branching points was reduced to 57.8 % of control. HTR-8/SVneo cell capacity to integrate into HUVEC monolayers was reduced by knock-down of MIF. This could be partly caused by reduced N-cadherin expression to 63 % of control, which decreased with knock-down of MIF, as the expression of this protein was recently shown essential for trophoblast-endothelial interaction. These novel findings indicate a novel role for trophoblast MIF in spiral artery remodeling process.

SIRT1 negatively regulates invasive and angiogenic activities of the extravillous trophoblast

PROBLEM

Dysregulation of extravillous trophoblast (EVT) invasion leads to pregnancy complications, such as pre-eclampsia, fetal growth restriction, and placenta accreta. The aim of this study was to explore the role of SIRT1 in EVT invasion and its underlying mechanism.

METHOD OF STUDY

SIRT1-specific siRNA was transfected into Swan 71 cells, an immortalized first trimester trophoblast cell line. The Boyden chamber invasion assay, the scratch wound healing assay, and cell proliferation assay were performed. The expression levels of epithelial-to-mesenchymal transition (EMT) markers, matrix metalloproteinase-2 (MMP-2), MMP-9, p-Akt, Akt, p-p38MAPK, p38MAPK, p-ERK, ERK, p-JNK, JNK, Fas, and Fas ligand (FasL) were examined by western blot. Tube formation assay was conducted by using Matrigel.

RESULTS

SIRT1 knockdown by siRNA significantly enhanced invasion and migration as well as the expression of MMP-2, MMP-9, and EMT markers in Swan 71 cells, but reduced proliferation. The effects of SIRT1 knockdown on invasion, migration, proliferation, and endothelial-like tube formation in Swan 71 cells were reversely regulated by blockade of Akt and p38MAPK signaling. In addition, SIRT1 knockdown markedly promoted colocalization of Swan 71 cells to human umbilical vein endothelial cell (HUVEC) networks and induced reduction in Fas and enhancement of FasL. Conditioned media of SIRT1 knockdown-Swan 71 cells caused reduction in cell proliferation and augmentation of cytotoxicity along with increased Fas expression in HUVECs.

CONCLUSION

Our results suggest that SIRT1 may be associated with placental development by controlling EVT invasion and spiral artery remodeling via modulation of EMT, MMP-2, MMP-9, Akt/p38MAPK signaling, and Fas/FasL.

Silencing BRIT1 Facilitates the Abilities of Invasiveness and Migration in Trophoblast Cells

Background

The improper invasion of trophoblast cells (TC) can cause various diseases. BRCT-repeat inhibitor of hTERT expression (BRIT1) is involved in the invasion of tumors. Here, we analyzed the effects of BRIT1 on the invasion of TC.

Material/Methods

The expression of BRIT1 in JEG-3, B6Tert, and HTR8/SVneo cells was evaluated by transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting. The viability, invasion, and migration of HTR8/SVneo cells were measured using cell counting kit-8 (CCK-8) and Transwell assays. The activities of pro-matrix metalloproteinase-2 (pro-MMP-2) and pro-MMP-9 were tested by gelatin zymography assay. The levels of invasion- and Wnt/β-catenin pathway-related factors were assessed by RT-qPCR and Western blotting.

Results

Levels of BRIT1 in HTR8/SVneo cells were higher than that of JEG-3 and B6Tert cells. The transfection efficiency of BRIT1 siRNA-2 was better than BRIT1 siRNA-1 in HTR8/SVneo cells. BRIT1 siRNA-2 did not change cell viability, whereas it promoted cell invasion and migration. BRIT1 siRNA-2 enhanced the activities of pro-MMP-2 and pro-MMP-9, as well MMP-2 and MMP-9 levels, and reduced tissue inhibitor of metalloproteinases-1 (TIMP-1) and TIMP-2 expression. Moreover, BRIT1 siRNA-2 significantly increased the levels of Wnt2, Wnt3, and β-catenin.

Conclusions

BRIT1 silencing accelerated the invasion and migration of TC and activated the Wnt/β-catenin pathway. Our results may provide new insights for finding new molecular targets to cure disease caused by insufficient invasion of TC.

Aggregation of Human Trophoblast Cells into Three-Dimensional Culture System Enhances Anti-Inflammatory Characteristics through Cytoskeleton Regulation

BACKGROUND

Three-dimensional (3D) culture changes cell characteristics and function, suggesting that 3D culture provides a more physiologically relevant environment for cells compared with 2D culture. We investigated the differences in cell functions depending on the culture model in human trophoblast cells (Sw.71).

METHODS

Sw.71 cells were incubated in 2D monolayers or simple 3D spheroids. After incubation, cells were corrected to assess RNA-seq transcriptome or protein expression, and culture medium were corrected to detect cytokines. To clarify the role of actin cytoskeleton, spheroid Sw.71 cells were treated mycalolide B (inhibitor of actin polymerization) in a 3D culture.

RESULTS

RNA-seq transcriptome analysis, results revealed that 3D-cultured cells had a different transcriptional profile compared with 2D-cultured cells, especially regarding inflammation-related molecules. Although interleukin-6 (IL-6) mRNA level was higher in 3D-culured cells, its secretion levels were higher in 2D-cultured cells. In addition, the levels of mRNA and protein expression of regnase-1, regulatory RNase of inflammatory cytokine, significantly increased in 3D culture, suggesting post-translational modification of IL-6 mRNA via regnase-1. Treatment with mycalolide B reduced cell-to-cell contact to build 3D formation and increased expression of actin cytoskeleton, resulting in increased IL-6 secretin.

CONCLUSION

Cell dimensionality plays an essential role in governing the spatiotemporal cellular outcomes, including inflammatory cytokine production and its negative regulation associated with regnase-1.