Expression of laminin receptor 1 in human placentas from normal and preeclamptic pregnancies and its relationship with the severity of preeclampsia

Laminin receptor 1 expression in premalignant and malignant squamous lesions of the cervix

Laminin receptor 1 (LAMR) may have a role in the progression of premalignant squamous epithelial lesions to cervical cancer. Therefore, we aimed to investigate the expression of laminin receptor 1 (LAMR) in normal, premalignant, and malignant tissues of the uterine cervix. Paraffin blocks of 129 specimens with the diagnoses of normal cervical tissue (n = 33), cervical intraepithelial neoplasia (CIN) 1 (n = 30), CIN 2 (n = 14), CIN 3 (n = 28), and squamous cell carcinoma (n = 24) were immunohistochemically stained with LAMR antibody and its expression percentage, pattern, and intensity in these tissues were assessed. Compared to the other groups, the nonstaining with LAMR was highest in low grade squamous intraepithelial lesion (LSIL) (p < 0.0001). LAMR expression, which was positive in less than 50% of cells with weak staining, increased significantly between normal cervical epithelium and high-grade squamous intraepithelial lesion (HSIL) or invasive carcinoma, as well as between LSIL and HSIL (p < 0.0001). Between LSIL and invasive carcinoma, a significant increment was also observed for weak staining in less than 50% of cells (p < 0.001). LAMR expression, which was positive in more than 50% of cells with strong staining, was significantly higher in normal cervical tissue compared to the other groups (p < 0.0001). Disease progression related gradual increment of LAMR expression from normal cervical epithelium or LSIL towards HSIL or cervical cancer reveals that LAMR may play an important role in the transition from premalignant to malignant state in cervical lesions.

Exploring the relationship between preeclampsia and human epididymis protein 4

Background/Aim: The level of human epididymis protein 4 (HE4), a glycoprotein and protease inhibitor, increases under many malignancies and inflammatory conditions. HE4 is also associated with cell invasion, migration, and adhesion. In this study, we compared the HE4 protein levels in pregnant patients with preeclampsia to healthy pregnant and non-pregnant individuals with the aim of finding a biomarker that can be used to recognize preeclampsia. Methods: Our study is a prospective case control study and included 20 pregnant women with preeclampsia, 20 pregnant women without preeclampsia, and 20 healthy non-pregnant women (the control). The participants’ serum HE4 levels were analyzed statistically. Results: Data analysis revealed that the mean HE4 levels were significantly lower in the preeclampsia group than in the other two groups (P = 0.002). Mean HE4 protein levels were also lower in the non-pregnant women than in the pregnant women without preeclampsia; however, this difference was not significant. Conclusion: It is difficult to predict preeclampsia, and there is not any sensitive or specific biomarker for determining the condition. This study may support that HE4 protein may be useful and significant in predicting preeclampsia. The results we achieved provide proof that HE4 levels could be a potential biomarker for preeclampsia. Many more comprehensive studies are needed to support the association between HE4 protein and preeclampsia.

The Downregulation of Placental Lumican Promotes the Progression of Preeclampsia

Multiple pieces of evidence illustrate that impaired trophoblast function results in preeclampsia (PE), and migration/invasion of human trophoblast cells is stringently regulated by extracellular matrix (ECM) components. Many studies have indicated abnormal expressions of placental ECM components are associated with preeclampsia. However, the change and influence of lumican, a vital member of extracellular matrix (ECM) molecules, on trophoblast cells during preeclampsia remain unclear. This study examines the possibility that the roles of lumican in trophoblast cells contribute to PE. To address this issue, the expression of lumican in human placental tissues was observed using immunohistochemistry, fluorescence quantitative PCR, and Western blot technology. After the HTR-8/SVneo cell line was transfected with pcDNA3.1-human lumican, pGPU6-human lumican shRNA, and their negative controls, the impact of lumican on the HTR-8/SVneo cell line was investigated. Lumican was expressed in human placental tissues. Compared with the control group, its expression was significantly lower in PE placentas. Lumican downregulation inhibited cell proliferation significantly and reduced Bcl-2 expression, but increased P53 expression. These results indicate that the downregulation of placental lumican may drive PE development via promoting the downregulation of Bcl-2 expression and upregulation of P53.

Laminins Regulate Placentation and Pre-eclampsia: Focus on Trophoblasts and Endothelial Cells

Pre-eclampsia is a systemic vascular disease characterized by new-onset hypertension and/or proteinuria at ≥20 weeks of gestation and leads to high rates of maternal and perinatal morbidity and mortality. Despite the incomplete understanding of pre-eclampsia pathophysiology, it is accepted that insufficient spiral artery remodeling and endothelial dysfunction are major contributors. Laminins (LNs) are a vital family of extracellular matrix (ECM) molecules present in basement membranes that provide unique spatial and molecular information to regulate implantation and placentation. LNs interact with cell surface receptors to trigger intracellular signals that affect cellular behavior. This mini-review summarizes the role of LNs in placental development during normal pregnancy. Moreover, it describes how LN deficiency can lead to the pre-eclampsia, which is associated with trophoblast and vascular endothelial dysfunction. New research directions and the prospect of clinical diagnosis of LN deficiency are discussed, and the gaps in basic and clinical research in this field are highlighted.

The role of serum interleukin-37 levels, inflammation and blood pressure in patients with preeclampsia

AIM

Preeclampsia is one of the major causes of perinatal, fetal, and maternal mortality and morbidity. The aim of this study was to investigate the association of serum interleukin 37 (IL 37) with preeclampsia.

METHODS

39 women with preeclampsia were included as the study group. 38 healthy, and normotensive pregnant women, at similar gestational week with similar gravidity volunteered as the control group. Clinical findings, biochemical parameters, maternal and perinatal outcomes, and the serum concentrations of IL37 were compared between the groups. The relationship of IL 37 concentrations with clinical findings and blood pressure outcomes were also investigated.

RESULTS

Maternal serum IL 37 concentrations were significantly higher in patients with preeclampsia compared to the healthy pregnant women in the control group (p = .005). IL 37 positively correlated systolic blood pressure (BP) (r = 0.344, p = .002), and diastolic BP (r = 0.332, p = .003). IL 37 was identified as an independent predictor of preeclampsia.

CONCLUSIONS

Serum IL 37 concentrations were higher in preeclamptic patients compared to healthy pregnant women. Furthermore, IL 37 concentrations achieved success in identifying preeclampsia with hypertension. Increased IL 37 activity may have a role in the pathophysiology of preeclampsia.

Expression of Laminin Receptor 1 in Normal, Hyperplastic, and Malignant Endometrium

Laminin receptor 1 may have a role in the progression from endometrial hyperplasia with or without atypia to endometrial cancer. Therefore, we aimed to investigate the pattern, percentage, and intensity of laminin receptor 1 expression in normal, hyperplastic, and neoplastic endometrium. Paraffin blocks of 131 specimens with the diagnoses of normal endometrium (n=25), endometrial hyperplasia with atypia (n=21) or without atypia (n=55), and endometrial cancer (n=30) were immunostained with laminin receptor 1 antibody, and its expression percentage, pattern, and intensity in the epithelial cytoplasm, basement membrane, and endometrial stroma of these tissues were assessed. When compared with hyperplasia with or without atypia and endometrial cancer, the percentage of nonstaining with laminin receptor 1 in the epithelial basement membrane was higher (96%), and the percentage of <50% staining with laminin receptor 1 was lower (4%) in the normal endometrium (P=0.001). While a progressive increment in staining percentage and density of epithelial cytoplasm and basement membrane was noted through an orderly progression from normal endometrium to endometrial hyperplasia without atypia, endometrial hyperplasia with atypia, and cancer of endometrium (P<0.001), such a relationship was not found for the staining percentage and density of endometrial stroma (P>0.05). Disease progression-related gradual increment in laminin receptor 1 expression in the epithelial basement membranes of hyperplastic endometrium with or without atypia and cancer of endometrium reveals that it may play a substantial role in the transition from premalignant to the malignant state of endometrial lesions.

Placental basement membrane proteins are required for effective cytotrophoblast invasion in a three-dimensional bioprinted placenta model

Fetal cytotrophoblast invasion of maternal decidual vasculature is necessary to normal pregnancy. In preeclampsia, there is shallow invasion and abnormal remodeling of the uterine vasculature that lead to significant maternal and perinatal morbidity and mortality. The placental basement membrane (BM) proteins (e.g., laminin and collagen) has been implicated in the development of placenta while the level of laminin is significantly lower in preeclampsia. However, there are very limited studies, if any, on the effect of extracellular matrix (ECM) microenvironment on the invasion of cytotrophoblast. In this study, we hypothesized that placental BM proteins are required for effective cytotrophoblast invasion. Using proteomics, we found that more than 80% of ECM proteins in placental basal plate (pECM) were BM proteins. In addition to upregulating expressions of MMP2 (1.5-fold) and MMP9 (6.3-fold), pECM significantly increased the motility rates of cytotrophoblasts by 13-fold (from 5.60 ± 0.95 to 75.5 ± 21.8 µm/day) to achieve an effective invasion rate that was comparable to in vivo results. Treatments with PI3K inhibitors completely removed the pECM-enhanced invasive phenotypes and genotypes of cytotrophoblasts, suggesting its dominant role in cytotrophoblast-ECM interactions. Our results described, for the first time, the substantial effects of the ECM microenvironment on regulating cytotrophoblast invasion, an area that is less investigated but appear to be critical in the pathogenesis of preeclampsia. Moreover, the approach presented in this work that fabricates organ models with organ-specific ECM can be an attractive option to screen and develop novel therapeutics and biomarkers not only in preeclampsia but also other diseases such as cancer metastasis. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1476-1487, 2018.

67-kDa Laminin receptor contributes to hypoxia-induced migration and invasion of trophoblast-like cells by mediating matrix metalloproteinase-9

Insufficient trophoblast invasion often occurs in patients experiencing preeclampsia. The 67-kDa laminin receptor (LR1) is a multifunctional protein that binds to laminin and interacts with the extracellular matrix. We recently demonstrated that LR1 is implicated in trophoblast migration and invasion. However, whether LR1 is involved in hypoxia-mediated trophoblastic invasion remains unclear and requires further investigation. This study demonstrates that two trophoblast-like cell lines (JEG3 and BeWo cells) cultured at 3% oxygen exerted enhanced migratory and invasive capabilities as compared with their counterparts exposed to 20% oxygen. LR1 expression was increased in hypoxic JEG3 cells but decreased after transfection with hypoxia-inducible factor 1 alpha (HIF-1α) specific siRNA. Moreover, shRNA targeting LR1 mRNA significantly inhibited hypoxia-induced increase in matrix metalloproteinase (MMP)-9 activity in JEG3 cells. Forced overexpression of LR1 augmented JEG3 cell migration and invasion, and enhanced MMP-9 expression and activity. Additionally, the blockade of the MMP-9 effect with its neutralizing antibody reduced LR1 elevation-promoted trophoblastic invasion. In summary, this study demonstrates that LR1 contributes to hypoxia-induced migration and invasion of trophoblast cells at least partly by mediating MMP-9 in vitro.

Slc20a2 deficiency results in fetal growth restriction and placental calcification associated with thickened basement membranes and novel CD13 and lamininα1 expressing cells

The essential nutrient phosphorus must be taken up by the mammalian embryo during gestation. The mechanism(s) and key proteins responsible for maternal to fetal phosphate transport have not been identified. Established parameters for placental phosphate transport match those of the type III phosphate transporters, Slc20a1 and Slc20a2. Both members are expressed in human placenta, and their altered expression is linked to preeclampsia. In this study, we tested the hypothesis that Slc20a2 is required for placental function. Indeed, complete deficiency of Slc20a2 in either the maternal or embryonic placental compartment results in fetal growth restriction. We found that Slc20a2 null mice can reproduce, but are subviable; ∼50% are lost prior to weaning age. We also observed that 23% of Slc20a2 deficient females develop pregnancy complications at full term, with tremors and placental abnormalities including abnormal vascular structure, increased basement membrane deposition, abundant calcification, and accumulation of novel CD13 and lamininα1 positive cells. Together these data support that Slc20a2 deficiency impacts both maternal and neonatal health, and Slc20a2 is required for normal placental function. In humans, decreased levels of placental Slc20a1 and Slc20a2 have been correlated with early onset preeclampsia, a disorder that can manifest from placental dysfunction. In addition, preterm placental calcification has been associated with poor pregnancy outcomes. We surveyed placental calcification in human preeclamptic placenta samples, and detected basement membrane-associated placental calcification as well as a comparable lamininα1 positive cell type, indicating that similar mechanisms may underlie both human and mouse placental calcification.

Intrauterine trophoblast migration: A comparative view of humans and rodents

Trophoblast migration and invasion through the decidua and maternal uterine spiral arteries are crucial events in placentation. During this process, invasive trophoblast replace vascular endothelial cells as the uterine arteries are remodeled to form more permissive vessels that facilitate adequate blood flow to the growing fetus. Placentation failures resulting from either extensive or shallow trophoblastic invasion can cause pregnancy complications such as preeclampsia, intrauterine growth restriction, placenta creta, gestational trophoblastic disease and even maternal or fetal death. Consequently, the use of experimental animal models such as rats and mice has led to great progress in recent years with regards to the identification of mechanisms and factors that control trophoblast migration kinetics. This review aims to perform a comparative analysis of placentation and the mechanisms and factors that coordinate intrauterine trophoblast migration in humans, rats and mice under physiological and pathological conditions.

RNA interference-mediated silencing of laminin receptor 1 (LR1) suppresses migration and invasion and down-regulates matrix metalloproteinase (MMP)-2 and MMP-9 in trophoblast cells: implication in the pathogenesis of preeclampsia

Shallow trophoblast invasion is a common pathological feature of preeclampsia. The 67 kDa laminin receptor 1 (LR1) is a laminin-binding protein that has been reported to be down-regulated in preeclamptic placentas. The aim of the present study was to determine the functional role of LR1 in the migration and invasion of the trophoblast cell line, JEG3 cells. RNA interference mediated by plasmid expressing LR1 short hairpin RNA (shRNA) was utilized to knockdown LR1 expression in JEG3 cells. We found that the mRNA and protein expression levels of LR1 were significantly reduced in LR1-specific shRNA transfected cells compared with the untransfected and control shRNA transfected cells. The wound healing and Transwell invasion assays demonstrated that LR1 knockdown remarkably suppressed the migration and invasion potential of JEG3 cells. The gelatin zymography assay showed that LR1 knockdown greatly reduced matrix metalloproteinase (MMP)-2 and MMP-9 activities in the culture supernatants. Western blot analysis showed that LR1 shRNA significantly decreased expression levels of MMP-2, MMP-9 and phospho-extracellular signal-regulated kinase, but increased expression levels of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 in comparison to the control vector-transfected cells. In conclusion, our data support an important role for LR1 in regulating trophoblast invasion and migration, and suggest a possible pathological mechanism of preeclampsia.

The role of genetics in pre-eclampsia and potential pharmacogenomic interventions

The pregnancy-specific condition pre-eclampsia not only affects the health of mother and baby during pregnancy but also has long-term consequences, increasing the chances of cardiovascular disease in later life. It is accepted that pre-eclampsia has a placental origin, but the pathogenic mechanisms leading to the systemic endothelial dysfunction characteristic of the disorder remain to be determined. In this review we discuss some key factors regarded as important in the development of pre-eclampsia, including immune maladaptation, inadequate placentation, oxidative stress, and thrombosis. Genetic factors influence all of these proposed pathophysiological mechanisms. The inherited nature of pre-eclampsia has been known for many years, and extensive genetic studies have been undertaken in this area. Genetic research offers an attractive strategy for studying the pathogenesis of pre-eclampsia as it avoids the ethical and practical difficulties of conducting basic science research during the preclinical phase of pre-eclampsia when the underlying pathological changes occur. Although pharmacogenomic studies have not yet been conducted in pre-eclampsia, a number of studies investigating treatment for essential hypertension are of relevance to therapies used in pre-eclampsia. The pharmacogenomics of antiplatelet agents, alpha and beta blockers, calcium channel blockers, and magnesium sulfate are discussed in relation to the treatment and prevention of pre-eclampsia. Pharmacogenomics offers the prospect of individualized patient treatment, ensuring swift introduction of optimal treatment whilst minimizing the use of inappropriate or ineffective drugs, thereby reducing the risk of harmful effects to both mother and baby.