Expression of Bcl-2 and p53 at the fetal-maternal interface of rhesus monkey

Association between TP53 Arg72Pro variant and recurrent pregnancy loss in the Greek population

OBJECTIVES

The present case-control study investigates whether TP53 Arg72Pro variant (rs1042522) serves as a risk factor for recurrent pregnancy loss (RPL) in Greek women.

METHODS

The study group consisted of 100 patients with at least two miscarriages of unexplained etiology, before the 24th week of gestation. The control group included 106 women with no pregnancy loss history. DNA was extracted and genotyped using specific primers for PCR amplification of the Arg72 and Pro72 alleles. Sanger sequencing was used for the discrimination between heterozygotes and homozygotes for Arg72Pro variant.

RESULTS

This is the first study demonstrating the statistically significant higher frequency of TP53 Arg72Pro variant in Greek RPL women compared to controls (38% vs. 6.6%; OR=8.6682, 95% CI: 3.6446-20.6160; p<0.0001). GC genotype (Arg/Pro) and CC genotype (Pro/Pro) were statistically more common in RPL patients than in controls (16% vs. 1.9%; p=0.0027, and 22 vs. 4.7%; p=0.0008, respectively). C allele frequency was statistically significant higher in RPL group than in controls (30.0 vs. 5.7%; p<0.0001). According to the inheritance mode analysis, the model that best fit the data was the dominant model (OR=8.67, 95% CI=3.64-20.62; p<0.0001).

CONCLUSIONS

The is the first study disclosing strong evidence that TP53 rs1042522 is significantly associated with a higher risk for recurrent pregnancy loss in Greek women following a dominant model, thus, serving as a genetic marker for identifying women at increased risk of recurrent miscarriages.

Evaluation of Apoptosis, Proliferation, and Adhesion Molecule Expression in Trophoblastic Tissue of Women With Recurrent Spontaneous Abortion and Infected With Toxoplasma gondii

Recurrent spontaneous abortion is an obstetric complication with undefined causes. Apoptosis, proliferation, and adhesion are considered important factors in the pathogenesis of abortion. This work aimed to determine Bax and Bcl-2 as a proapoptotic and antiapoptotic protein, Ki67 and P27kip as proliferative and antiproliferative proteins, and E-cadherin and CD44 as adhesion molecules in the trophoblastic tissues in cases with recurrent miscarriage. Immunohistochemistry and quantitative polymerase chain reaction analysis of Bax, Bcl-2, Ki67, P27kip, E-cadherin, and CD44 in paraffin-embedded sections of placental tissues obtained from 108 women were divided into 3 categories: 66 Toxoplasma gondii-positive women with recurrent abortion, 22 T. gondii-negative women with recurrent abortion, and 20 women with no history of abortion as a control group. The mean ratio of the expression of Bax and P27kip proteins was 35.3% and 36.1%, which is significantly higher than that of the second group (19.88 and 20.02%), and the third group (12.3% and 10.98%), while the mean ratio of the expression of Bcl-2, Ki67, E-cadherin, and CD44 proteins was 12.35%, 11.23%, 10.32%, and 9.97%, which is significantly lower than that of the second group (33.75%, 13.18%, 21.88%, and 23.29%) and that of the third group (38.58%, 39.27%, 37.98%, and 35.79%). The presence of proapoptotic protein (Bax) and antiproliferative protein (P27kip) at high levels and the presence of antiapoptotic protein (Bcl-2), proliferative protein (Ki67), and adhesion molecules (E-cadherin and CD44) in lower levels in the T. gondii-positive group clarify the mechanism involved in the induction of abortion and loss of pregnancy.

MNSFβ Promotes the Proliferation and Migration of Human Extravillous Trophoblast Cells and the Villus Expression Level of MNSFβ Is Decreased in Recurrent Miscarriage Patients

AIMS

The invasion of extravillous trophoblast (EVT) cells into maternal decidua is essential for the establishment and maintenance of pregnancy. Derangement of EVT cell invasion might cause pregnancy complications including recurrent miscarriage (RM). We previously reported that deficiency of monoclonal nonspecific suppressor factor beta (MNSFβ) led to the early pregnancy failure in mice and the decidual MNSFβ expression level in RM patients was significantly decreased, but the underlying molecular mechanism of the role that MNSFβ played at the maternal-fetal interface remains unclear. Thus, in the present study, we determined effects of downregulated MNSFβ expression on human EVT cell activities.

METHODS

The MNSFβ expression in first-trimester human decidual and placental villus tissues was detected, respectively, by immunofluorescence or immunohistochemical analyses. The MNSFβ expression level in the immortalized first-trimester human EVT cell line HTR8/SVneo was downregulated by transfecting the small interfering RNA against MNSFβ and upregulated by transfecting the recombinant pDsRed-MNSFβ plasmids. The proliferation, migration, invasion, and apoptosis activities of HTR8/SVneo cells were, respectively, determined by cytometry assay, scratch test, transwell assay, and FITC/PI staining. The expression levels of P53, RhoA, Bcl-2, Bax, and MMP-9 in HTR8/SVneo cells, as well as the expression levels of MNSFβ and RhoA in placental villi of RM patients and physically normal pregnant women (NP), were examined by Western blot analysis.

RESULTS

MNSFβ protein signals were observed in first-trimester human villus and extravillous trophoblast cells. The downregulated MNSFβ expression significantly attenuated the proliferation, migration, and invasion abilities of HTR8/SVneo cells, accompanied with the obviously decreased expression levels of P53, RhoA, Bcl-2, Bax, and MMP-9, whereas the upregulated MNSFβ expression in HTR8/SVneo cells represented the inverse effects. Furthermore, expression levels of MNSFβ and RhoA in first-trimester human placental villus tissues of RM patients were significantly decreased compared to that of NP women.

CONCLUSION

These data suggested that MNSFβ promotes proliferation and migration of human EVT cells, probably via the P53 signaling pathway, and the deficiency of MNSFβ in placental villi might lead to early pregnancy loss by reducing proliferation and invasion activities of EVTs.

The role of NFκB in the three stages of pregnancy - implantation, maintenance, and labour: a review article

The transcription factor nuclear factor kappa B (NFκB) controls the expression of over 400 genes, some of which are associated with reproductive events. During implantation, immune cells accumulate in the maternal-fetal interface; they secrete inflammatory mediators under the control of NFĸB, the level of which also rises. NFĸB is then downregulated to maintain gestation, but its level rises again before birth to manage prostaglandin, cytokine, and chemokine synthesis, and to stimulate uterine contraction. This review summarises the current state of knowledge about NFκB and its role in the molecular regulation of processes related to pregnancy development.

TWEETABLE ABSTRACT

This review examines the current state of knowledge about role of NFκB in the development of pregnancy.

miR-3074-5p Promotes the Apoptosis but Inhibits the Invasiveness of Human Extravillous Trophoblast-Derived HTR8/SVneo Cells In Vitro

OBJECTIVE

The objective of this study was to observe the effects of the overexpression of miR-3074-5p in human trophoblast cells in vitro.

DESIGN

Experimental in vitro study in HTR8/SVneo cells.

METHODS

HTR8/SVneo cells were transfected with miR-3074-5p mimic. The cell apoptosis and invasion were measured via flow cytometry and transwell assay, respectively. The expression levels of P53, Cyclin Dependent Kinase Inhibitor 1B (P27), BCL-2, BCL2 associated X (BAX), and BCL2 like 14 (BCL-G) in HTR8/SVneo cells were determined by Western blot. The alterations in gene expression profile of HTR8/SVneo cells were evaluated by complementary DNA microarray assay, and the differential expressions of dihydrolipoamide S-succinyltransferase (DLST), growth-associated protein 43 (GAP43), runt-related transcription factor 2 (RUNX2), and C-C type chemokine receptor 3 (CCR3) were validated by Western blot. Biofunctions of these differentially expressed genes were enriched by Gene Ontology analysis.

RESULTS

The overexpression of miR-3074-5p in HTR8/SVneo cells promoted cell apoptosis but inhibited cell invasion, being accompanied by the significantly elevated expressions of P27, BCL-2, and BCL-G. Meanwhile, an increased expression of P27 and P57 was also detected in a small sample size of placental villi of recurrent miscarriage (RM) patients. Totally, 411 genes and 397 genes were screened out, respectively, to be downregulated or upregulated at least by 2-folds in miR-3074-5p overexpressed HTR8/SVneo cells. These differentially expressed genes were involved in several important functions related to pregnancy. Subsequently, the reduced expressions of DLST and GAP43 proteins, as well as the increased expressions of CCR3 and RUNX2 proteins, were validated in miR-3074-5p overexpressed HTR8/SVneo cells.

CONCLUSION

These data suggested a potential contribution of miR-3074-5p in the pathogenesis of RM by disturbing the normal activities of trophoblast cells.

Deep-sequencing identification of differentially expressed miRNAs in decidua and villus of recurrent miscarriage patients

PURPOSE

MicroRNAs (miRNAs) are small non-coding RNA molecules that play critical roles in post-transcriptional gene expression regulation. The aim of this study was to identify differentially expressed miRNAs in decidua and villus of recurrent miscarriage (RM) patients.

METHODS

Participants were recruited at the outpatient Department of Gynecology and Obstetrics, The Second Hospital of Tianjin Medical University, China. Decidua and villus tissues were collected by curettage from recruited RM patients and normal pregnant women with their informed consent. MiRNAs expression profiles in decidua or villus were respectively determined by the deep-sequencing analysis. The predicated target genes of these differentially expressed miRNAs were analyzed by miRWalk. The differential expressions of four miRNAs in decidua and four miRNAs in villus between the six pairs of RM patients and normal pregnant women were confirmed by qRT-PCR analysis. The expression patterns of two predicated target genes, Bcl-2 and Pten, in the same six pairs of decidual or villus tissues were detected by Western blotting analysis, respectively.

RESULTS

Totally 18 RM patients and 15 normal pregnant women were recruited. Thirty-two miRNAs in decidua and four miRNAs in villus of RM patients were screened out to be significantly up-regulated compared to that of normal pregnant women, and five miRNAs in villus of RM patients were screened out to be remarkably down-regulated compared to that of normal pregnant women (P value < 0.05 and Fold change >2). These differentially expressed miRNAs were predicted to target a large number of genes that involved in cell apoptosis, p53 signaling pathway, cell cycle and other cellular bio-functions. Differential expressions of hsa-miR-516a-5p, -517a-3p, -519a-3p and -519d in decidua, as well as hsa-miR-1, -372, -100-5p and -146a-5p in villus, were validated by qRT-PCR analysis. In the decidual of RM patients, expression of hsa-miR-516a-5p, -517a-3p, -519a-3p and -519d were significantly up-regulated compared to normal pregnancy. In the villi of RM patients, expression of hsa-miR-100 and -146a-5p were significantly higher, while hsa-miR-1 and -372 were significantly lower compared to normal pregnancy. Furthermore, the expression of Bcl-2 and Pten, a predicated target gene of hsa-miR-1 or hsa-miR-372 respectively, was significantly up-regulated in the villi of RM patients.

CONCLUSIONS

These data suggested that the pathogenic process of RM might be associated with the alteration of miRNAs expression profiles in decidua and villus. Especially, the aberrant placental expression of hsa-miR-1 and -372 might be involved in the progression of RM, but need to be further investigated by larger studies in the future.

p53 signaling pathway polymorphisms associated to recurrent pregnancy loss

The p53 protein is known for performing essential functions in the maintenance of genomic stability in somatic cells and prevention of tumor formation. Studies of the p53 signaling pathway have suggested associations between some polymorphisms and infertility, post-in vitro fertilization implantation failure and recurrent abortions. The TP53 Pro72Arg polymorphism has been implicated as a risk factor for recurrent pregnancy loss (RPL); however, the association is controversial. In this study, our objective was to evaluate selected polymorphisms in genes of the p53 signalling pathway [TP53 c.215G>C (Pro72Arg), MDM2 c.14+309T>G (SNP309) and LIF c.1414T>G in the region 3' UTR] and determine their effect as risk factors for RPL. In a case-control study, we investigated 120 women with two or more pregnancy losses and 143 fertile control women reporting at least two live births and no history of pregnancy loss. When analyzed separately, the allele and genotype distributions of the polymorphisms in the two groups were not different. However, in a multivariate analysis adjusted for alcohol consumption, smoking, ethnicity, and number of pregnancies, the interaction between the genotypes TP53 Arg/Arg (rs1042522) and MDM2 TT (rs2279744) showed to be associated to RPL, increasing the risk for this condition (OR = 2.58, 95% CI: 1.31-5.07, p = 0.006). In conclusion, our study indicates that the combination of TP53 Arg/Arg (rs1042522) and MDM2 TT (rs2279744) genotypes may be a risk factor for RPL.

Developmental patterns of Ki-67, bcl-2 and caspase-3 proteins expression in the human upper jaw

The distribution of the Ki-67, bcl-2 and caspase-3 proteins was immunohistochemically analyzed in the developing human upper jaw (5th-10th gestational weeks). During this period, proliferative activity gradually decreased from higher levels at the earliest stages (50-52%) to lower levels, both in the jaw ectomesenchyme and in the epithelium. The highest expression of bcl-2 protein was found in the epithelium and ectomesenchyme of areas displaying lower rates of cell proliferation. High levels of caspase-3 protein were detected during the earliest stages of jaw development, indicating an important role for apoptosis in morphogenesis of early derivatives of the maxillary prominences. The number of Ki-67, bcl-2 and caspase-3 positive cells changed in a temporally and spatially restricted manner, coincidently with upper jaw differentiation. While apoptosis might control cell number, bcl-2 could act in suppression of apoptosis and enhancement of cell differentiation. A fine balance between cell proliferation (Ki-67), death (caspase-3) and cell survival (bcl-2) characterized early human upper jaw development. A rise in the number of apoptotic cells always temporally coincided with the decrease in number of surviving bcl-2 positive cells within the palatal region. Therefore, the upper jaw development seems to be controlled by the precisely defined expression of genes for proliferation, apoptosis and cell survival.

Placental development during early pregnancy in sheep: cell proliferation, global methylation, and angiogenesis in the fetal placenta

To characterize early fetal placental development, gravid uterine tissues were collected from pregnant ewes every other day from day 16 to 30 after mating. Determination of 1) cell proliferation was based on Ki67 protein immunodetection; 2) global methylation was based on 5-methyl-cytosine (5mC) expression and mRNA expression for DNA methyltransferases (DNMTs)1,3a, and3b; and 3) vascular development was based on smooth muscle cell actin immunolocalization and on mRNA expression of several factors involved in the regulation of angiogenesis in fetal membranes (FMs). Throughout early pregnancy, the labeling index (proportion of proliferating cells) was very high (21%) and did not change. Expression of 5mC and mRNA forDNMT3bdecreased, but mRNA forDNMT1and3aincreased. Blood vessels were detected in FM on days 18–30 of pregnancy, and their number per tissue area did not change. The patterns of mRNA expression for placental growth factor, vascular endothelial growth factor, and their receptorsFLT1andKDR; angiopoietins 1 and 2 and their receptorTEK; endothelial nitric oxide synthase and the NO receptorGUCY13B; and hypoxia inducing factor 1 α changed in FM during early pregnancy. These data demonstrate high cellular proliferation rates, and changes in global methylation and mRNA expression of factors involved in the regulation of DNA methylation and angiogenesis in FM during early pregnancy. This description of cellular and molecular changes in FM during early pregnancy will provide the foundation for determining the basis of altered placental development in pregnancies compromised by environmental, genetic, or other factors.

Increased expression of heat shock protein 105 in rat uterus of early pregnancy and its significance in embryo implantation

BACKGROUND

Heat shock proteins (Hsps) are a set of highly conserved proteins, Hsp105, has been suggested to play a role in reproduction.

METHODS

Spatio-temporal expression of Hsp105 in rat uterus during peri-implantation period was examined by immunohistochemistry and Western blot, pseudopregnant uterus was used as control. Injection of antisense oligodeoxynucleotides to Hsp105 into pregnant rat uteri was carried out to look at effect of Hsp105 on embryo implantation.

RESULTS

Expression of Hsp105 was mainly in the luminal epithelium on day 1 of pregnancy, and reached a peak level on day 5, whereas in stroma cells, adjacent to the implanting embryo, the strongest expression of Hsp105 was observed on day 6. The immunostaining profile in the uterus was consistent with that obtained by Western blot in the early pregnancy. In contrast, no obvious peak level of Hsp105 was observed in the uterus of pseudopregnant rat on day 5 or day 6. Furthermore, injection of antisense oligodeoxynucleotides to Hsp105 into the rat uterine horn on day 3 of pregnancy obviously suppressed the protein expression as expected and reduced number of the implanted embryos as compared with the control.

CONCLUSION

Temporal and spatial changes in Hsp105 expression in pregnant rat uterus may play a physiological role in regulating embryo implantation.

Role of p53 codon 72 polymorphism in recurrent pregnancy loss

Recurrent pregnancy loss (RPL) has been associated with low expression of apoptosis-and angiogenesis-related genes. The p53 tumour suppressor gene has been shown to induce apoptosis and angiogenesis. Recently, a low increased frequency of a p53 codon 72 polymorphism has been reported among women experiencing RPL. This study investigated the prevalence of p53 codon 72 polymorphism among women with a history of RPL, to determine whether this polymorphism may serve as a risk factor for miscarriage. Buccal swabs were obtained from 205 women with a history of two or more consecutive spontaneous abortions and 25 women with at least two live births and not more than one elective abortion. DNA was extracted from the buccal swabs and PCR amplification of p53 arginine(Arg)72 and proline(Pro)72 variants was performed. The frequency of homozygous Arg and Pro or heterozygous Arg/Pro genotypes among RPL patients and controls were not significantly different. No significant differences in allelic frequencies of p53 were observed. In addition, the allelic frequencies between controls and those previously reported were the same. It is concluded that p53 codon 72 polymorphisms do not serve as a susceptibility factor affecting the chances of miscarriage in an unselected population.

Cloning of the bovine antiapoptotic regulator, BCL2-related protein A1, and its expression in trophoblastic binucleate cells of bovine placenta

This report studied the identification and sequence of a full-length cDNA for the bovine BCL2 antiapoptotic family member, BCL2-related protein A1 (BCL2A1), and its localized and quantitative expression in the placenta to clarify the regulatory mechanism of trophoblast cell proliferation and differentiation during implantation and placental development. We cloned a full-length bovine BCL2A1 cDNA with 725 nucleotides and an open-reading frame corresponding to a protein of 175 amino acids. The predicted amino acid sequence shared 78% homology with human BCL2A1. All BCL2 homology domains (BH1, BH2, BH3, and BH4) in bovine BCL2A1 were conserved as well as in other mammalian BCL2A1. In the placentomes, in situ hybridization demonstrated that the BCL2A1 was limited in binucleate cells expressing various pregnancy-specific molecules like placental lactogen. BCL2-associated X protein (BAX) was also expressed in binucleate cells. Quantitative real-time RT-PCR detection exhibited a high-level expression of BCL2A1 in the conceptus at Day 21 of gestation, and it was expressed and increased in the extraembryonic membrane, cotyledon, and intercotyledon from implantation to term. BAX expression intensity increased with progression of gestation and remained elevated in postpartum. Caspase-3 protein (CASP3) and mRNA (CASP3) were detected from late gestation to postpartum in placenta as well as in the results of TUNEL detection. We believe that the apoptosis of binucleate cells may be regulated by the balance of the BCL2A1 and BAX. BCL2A1 genes produced a BCL2A1 protein in the mammalian cell-expression system. This molecule is a new candidate for antiapoptotic maintenance of the binucleate cells that support placental functions throughout gestation in bovine.

Upregulation of Bcl-2 at the foetal-maternal interface from mice undergoing abortion

Several burning questions remain unanswered in pregnancy-related research. Pro- and anti-inflammatory cytokines orchestrate an intriguing interaction leading either to the development of a normal individual or to its rejection. Augmented Th1 cytokines' production is involved in immunological rejection of the foetus. Excessive production of Th1 cytokines, particularly of tumour necrosis factor (TNF)-alpha, also triggers apoptosis. Thus, in the present work we investigated the incidence of apoptosis in a well-known experimental model of Th1-induced abortion, characterized by increased local TNF-alpha levels. Apoptosis of lymphocytes as well as their Th1 and Th2 cytokine production were analysed by flow cytometry. TNF-alpha mRNA levels were additionally analysed by real time reverse transcription-polymerase chain reaction (RT-PCR) in placental and decidual samples. Total placental apoptosis activity was investigated by measuring caspase-3 activity and by TdT-mediated dUTP nick end label staining. Immunohistochemistry, Western blot and real time RT-PCR were used to localize and quantify several anti- and pro-apoptotic molecules at the foetal-maternal interface. Despite elevated Th1 levels at the foetal-maternal interface, mice undergoing abortion presented comparable apoptotic rates. Interestingly, we found a significant upregulation of the anti-apoptotic Bcl-2 protein at the foetal-maternal interface from abortion-prone mice, while no changes could be observed for pro-apoptotic molecules. In the light of our results, we conclude that there is no evidence of increased apoptosis in mice undergoing immunological abortion in spite of elevated TNF-alpha levels. This is probably due to a selective upregulation of anti-apoptotic pathways (i.e. Bcl-2) at the foetal-maternal interface as a compensatory and/or protective mechanism.