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Association of serum beta-hCG levels with myosalpingeal invasion and viable trophoblast mass in tubal pregnancy.

OBJECTIVE: To test the hypothesis that myosalpingeal invasion and viable trophoblast mass are associated with serum beta-hCG levels in tubal-ampullary pregnancy. METHODS: Twenty-seven salpingectomy specimens of tubal-ampullary pregnancies were assessed for the presence or absence of myosalpingeal invasion. The mass of viable trophoblast was quantified in terms of the number of high-power fields (x400) occupied. The cases were stratified into three groups: small, less than one field; medium, one or two fields; and large, more than two fields and/or embryo present. Beta-hCG was measured before the procedure (mIU/mL, Third International Standard). RESULTS: The mean (+/- standard error of the mean) beta-hCG level for the nine cases exhibiting myosalpingeal invasion was significantly higher than for the 18 cases without invasion (13,665 +/- 2986 versus 2169 +/- 870 mIU/mL; P = .0001). Beta-hCG levels greater than or equal to 5400 mIU/mL predicted myosalpingeal invasion in eight of nine cases (positive predictive value 89%). In contrast, levels less than 5400 mIU/mL were associated with lack of myosalpingeal invasion in 17 of 18 cases (negative predictive value 94%). The volume of trophoblast mass correlated with both beta-hCG levels (r = 0.647, P = .0003) and myosalpingeal invasion (r = 0.735, P = .0001). There was no invasion in the 13 cases in the group with small trophoblast mass, whereas two of five cases in the medium-mass group displayed myosalpingeal invasion. In this group, the mean beta-hCG for cases with myosalpingeal invasion was higher than in the cases without invasion (16,917 +/- 117 versus 3799 +/- 1094 mIU/mL; P = .003). In the group with large trophoblast mass, seven of nine specimens showed myosalpingeal invasion. CONCLUSION: Both myosalpingeal invasion and viable trophoblast mass correlate positively with serum levels of beta-hCG. Myosalpingeal invasion is highly likely when beta-hCG levels reach 5400 mIU/mL.

Chorionic Gonadotropin↗

[Studies on injury-mechanism of trichosanthin on trophoblast cells and choriocarcinoma cells in culture].

For analysing the injurious mechanism of Trichosanthin (TCS) on trophoblast cells, cytotrophoblast cells were separated from placental villi in human early pregnancy and cultured on millipore filters coated with collagen in dual-environmental culture chambers. After 7-10 days culture the cells grew into confluent monolayer. A lot of multinucleated giant cells (synthetial like) could be found under light microscopy. Cytotrophoblast cells and the giant one were characterized as epithelial type by indirect immuno-fluorescent staining with anti-keratin. Because the procedure of separation of trophoblast cells is laborious and the choriocarcinoma cells (JAR) were as sensitive as trophoblast cells to trichosanthin, so the choriocarcinoma cells were used instead of the trophoblast cells in the later experiments. The internalization and distribution of TCS conjugated to 15 nm (in diameter) gold particles were examined. Electron microscopy showed that the TCS-gold particles were bound to the cell membrane and entered via coated pit and then internalized into coated vesicles (endosomes) within 30-60 minutes after treatment. Nevertheless, a number of free TCS-gold particles entered into the cell membrane nonspecifically. In the series of 60-120 minutes treatment, the TCS-gold particles presented in the multivesicular bodies. It is worthy to emphasize that the TCS-gold particles entered the cytosol from the endosomes and distributed nearby the rough endoplasmic reticulum (RER) and ribosomes within 120-180 minutes. In the meanwhile, the cells showed pathological changes markedly. With the same method, human liver carcinoma cells (BE 7402), kidney cells of African green monkey (CV-1) and rat embryonic liver epithelial cells (LW 13) were treated by TCS-gold particles as control. However, no particles had been found on the cell surface or in the cytosol within 60-120 minutes (see Table 1). In addition, trophoblast cells were treated by BSA-gold particles and transferrin-gold particles separately there still no particles could be found. (See Table 2). It is more interesting that TCS-Hepama-1-gold particles internalized into the choriocarcinoma cells with the same manner as TCS-gold entered, and it could not be affected by pretreatment with Hepama-1 an hour. But, TCS-Hepama-1-gold particles bound to the microvilli of human liver carcinoma cells, and it can be inhibited competitively by pretreatment with Hepama-1 for an hour (see Table 3). These results indicated consistently that trichosanthin possesses a high affinity to the membrane of trophoblast cells and choriocarcinoma cells, and the internalization of this plant toxic protein into its target cells characterized by receptor-mediated endocytosis.(ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗

Collagenase-IV in human trophoblast invasion and differentiation.

Trophoblast cells are unique with respect to their functions and responsibilities. These cells demonstrate three sequential phenotypes, proliferation and invasion into the endometrium, differentiation to form syncytia and endocrine secretions. Equipped with these properties placental trophoblasts are endowed with a variety of functions, like implantation of the blastocyst to the endometrium, providing nutrition to the developing embryo and also transmitting extraordinary array of signals for the embryonic development. Experimental evidences and logical extrapolation suggest that these functions are precisely controlled by growth factors, cytokines and hormones produced either by the trophoblast themselves or by the utero-placental unit. Any error in this control mechanism has extremely adverse consequences. The cells also synthesize a large number of enzymes, amongst which collagenase type IV secretion is involved in digestion of underlying basement membrane necessary for the process of invasion. Our results implicate the enzyme in the functional differentiation of the trophoblast as well. Inhibitors to this enzyme inhibit trophoblast differentiation as monitored by secretion of hCG and progesterone, the two markers of trophoblastic differentiation. In contrast, BeWo cells, a choriocarcinoma cell line which does not differentiate spontaneously, undergo increased proliferation when challenged with EGF. The results indicate the possibility of invasive and differentiative phenotypes to be coupled. Exact molecular involvements in this coupling process are looked into.

Cell Differentiation↗

Metastatic placental site trophoblastic tumor.

Since our publication, which first defined the malignant potential of placental site trophoblastic tumor (PSTT), we have had a keen interest in this rare, unique entity. This histologic entity is noted by its monomorphic population of trophoblast-like cells which are classified as originating in the intermediate trophoblast. These cells contain hymman placental lactogen (HPL). This is in contrast to cytotrophoblastic and syncytiotrophblastic tissues as the histologic, cytologic and immunohistochemical stain characteristics are disparate. Its rarity and the wide spectrum of clinical behavior combined with the lack of sensitivity of serum levels of beta hCG in predicting disease recurrence and spread have lead to anecdotal reports outlining clinical management. Most discerning to the clinician is the high mortality of metastatic placental site trophoblastic tumor. At our institution, we have treated two patients with a metastatic disease with a successful conclusion. The durability of responses is 3 and 8 years. This report will present these patients in detail and define the important characteristics of successful treatment. The use of dose-intensive, multi-agent chemotherapy, early intervention when metastatic disease is discovered, imaging techniques to define disease spread, surgery for localized disease and the use of growth factors, most notably granulocyte colony-stimulating factor (G-CSF), are the fundamentals of clinical care of placental site trophoblastic tumor in patients with metastatic placental site trophoblastic tumor.

Antineoplastic Combined Chemotherapy Protocols↗

An Integrated Proteomics and Genomics Approach to Identify Essential Protein Kinases During Human Trophoblast Development.

In the developing human placenta, three subtypes of trophoblast cells, cytotrophoblasts (CTBs), extravillous trophoblasts (EVTs), and syncytiotrophoblasts (STBs), mediate critical functions essential for a successful pregnancy. CTBs constitute the stem/progenitor compartment and differentiate into STBs and EVTs within the floating and anchoring villi, respectively. STBs establish the maternal-fetal exchange interface and secrete human chorionic gonadotropin (hCG), a hormone vital for the maintenance of early pregnancy. EVTs anchor the maternal endometrium and invade the uterine tissue to remodel maternal cells, supporting implantation and progression of pregnancy. In this study, we used human trophoblast stem cells (hTSCs) as a model system and performed quantitative, label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) to profile the proteome and phosphoproteome in TSC stem state (analogous to undifferentiated CTBs) and following their differentiation to STBs and EVTs. Through a multiomics approach, we integrated our proteomics data with global gene expression profiles to correlate cell-type specific gene and protein expression during human trophoblast development. We also identified global phosphoproteome and analyzed kinases that are specifically active in hTSC stem state, as well as in differentiated STBs and EVTs. We experimentally validated specific kinases, such as BUB1B, PAK6, PKYMT1, and TNIK, that are essential for maintaining the hTSC stem-state. Additionally, atypical protein kinase C isoforms PKCζ are essential for STB development, whereas PTK2B, SRC, TRIO, and LYN are important for EVT development. Our findings highlight key kinases uniquely required for specific stages of trophoblast development during human placentation and suggest that pharmacological inhibition of these kinases could negatively impact the placentation process during pregnancy.

Humans↗

Human trophoblast xenografts in athymic mice: a model for peripheral aromatization.

A novel procedure was developed for evaluating aromatase inhibitors using human enzyme in a rodent model. Human choriocarcinoma trophoblast (JAr line) cells injected subcutaneously into athymic nude mice develop into tumor xenografts in 7-14 days which represent sites for peripheral aromatization of androgens. The rapid growth of these trophoblast tumors is estrogen independent. The tumors provide a source of nonovarian human tissue which has relatively high levels of enzyme activity (248 +/- 12 pmol estrogen/g/h) for biochemical determination of in vivo aromatase inhibition. These are major advantages for pharmacological evaluations in comparison to the slow tumor growth response of most carcinogen-induced rodent mammary cancers, which are usually devoid of aromatase activity. In addition, the hormonal dependent components of rodent mammary tumors require several weeks to regress as a result of the indirect effects of estrogen deprivation on tumor growth via inhibition of prolactin dependency, a minor component relative to the role estrogen occupies in hormonally-dependent breast cancer in humans. This model of peripheral aromatization was utilized to evaluate in vivo pharmacological parameters of MDL 18,962 (10-(2-propynyl)estr-4-ene-3,17-dione) such as bioavailability of several formulations, time course and dose responses following different routes of drug administration, pharmacokinetics and tissue distribution of [14C]MDL 18,962. Tumor aromatase activities of trophoblast xenografts were significantly (P less than or equal to 0.05) inhibited when MDL 18,962 was administered intravenously, orally, subcutaneously, or via subcutaneous silastic implants. The ED50 of MDL 18,962 for tumor aromatase inhibition at 6 h after a single treatment was 1.4 mg/kg, s.c. and 3.0 mg/kg, orally. MDL 18,962 blocked aromatase activity more effectively in human trophoblast than in mouse ovarian tissue. Human trophoblast aromatase activity was inhibited by 70% following a single oral dose of 100 mg/kg of MDL 18,962, while the host's ovarian aromatase activity exhibited only marginal inhibition. In vitro, the addition of 10 microM MDL 18,962 to trophoblast tumor cytosol or mouse ovarian cytosol resulted in 99.6 and 91.4% inhibition of aromatase activity, respectively. Tissue distribution of [14C]MDL 18,962 was predominantly associated with endocrine tissues with aromatase activity and organ systems involved in steroid metabolism and excretion. These in vivo data show that MDL 18,962 an enzyme-activated aromatase inhibitor, causes prolonged aromatase inhibition in the absence of saturating levels of inhibitor.

Androstenedione↗

Erythrophagocytosis in the caprine trophoblast.

The mechanism of iron transfer by extravasation of maternal blood in the maternal-fetal interface and the subsequent phagocytosis of the erythrocytes by the trophoblast cells was described in ovine, bovine and other species. This research was performed due to the absence of studies on this process in the goat. Fragments of placentomes were obtained from 9 adult goats of an unspecified breed and were separated into Groups A, B and C, based on 90, 120 and 150 d of gestation, respectively. Fragments of 3 placentomes were obtained from each animal of all groups. The first of them was removed from the base, the second from the middle part and the third from the end of the gestational uterine horn. The fragments were fixed in Bouin solution and histologically processed according to the usual paraffin inclusion techniques. The slides were stained by hematoxilin-eosin and potassium ferrocyanide and examined under light microscopy The erythrophagocytosis (EP) process of the trophoblast was identified in all the examined histological sections, throughout the gestation and for each placentome. An accumulation of spots of blood was observed only in the maternal-fetal interface located in the arcade zone of the placentome. The main cells of the trophoblast of these areas presented an intense phagocytic activity and the observation of erythrocytes with hemossiderin pigments in their citoplasm was possible. The trophoblast epithelium of these areas was thicker and with a columnar aspect than the cubic aspect observed in other areas. The trophoblast binucleate cells do not seem to participate in EP. Our findings indicate that the phagocitosis process of the maternal erythrocites by the trophoblast also occurs in caprine species, indicating that this could be a mechanism of transplacentary transfer of iron in this species.

Journal Article↗

Transplacental drug delivery: gene and virus delivery to the trophoblast.

The development of successful strategies for delivering genes to the placenta may provide new opportunities for modifying trophoblast function in order to learn more about trophoblast physiology and to offer novel therapeutic options for complications of pregnancy that result from placental dysfunction. Replication-deficient recombinant viral vectors are useful vehicles for introducing genes into cells in vitro and in vivo. Recombinant adenovirus and herpes simplex virus vectors are unable to efficiently infect and transduce terminally differentiated trophoblastic cells. However, recombinant adeno-associated virus vectors transduce terminally differentiated trophoblastic cells, and a Sindbis virus construct efficiently transduces and destroys trophoblastic cancer cells. We describe the features that make particular viral vectors attractive for gene transfer to trophoblastic cells.

Journal Article↗

Nicked human chorionic gonadotropin in trophoblastic disease.

The objectives of this study were to determine: 1) whether high proportions of nicked human chorionic gonadotropin (hCG) in serum at the time of mole evacuation and during postmolar surveillance is indicative of trophoblastic malignancy and 2) to investigate whether measurement of nicked hCG provides clinically more useful information in the management of patients with trophoblastic disease than does measurement of total hCG alone. "Tumor marker" total hCG, intact hCG, and nicked hCG were measured in serial samples of serum from our serum bank of patients with representative types of trophoblastic disease. "Tumor marker" hCG has been shown to measure all aspects of the hCG molecule. At the time of presentation of all 45 patients, 83.5% of hCG was intact and 16.5% was nicked. These proportions became reversed as hCG declined either spontaneously after hydatidiform mole evacuation or with chemotherapy in patients with postmolar trophoblastic tumor or with metastatic trophoblastic disease. We conclude that the proportion of nicked hCG compared to intact hCG increases with trophoblastic disease resolution. Measurement of nicked hCG adds no useful clinical information to that provided by reliable measurement of total hCG.

Journal Article↗

[The expressions of p16, CDK4 and PCNA proteins in trophoblastic tumors].

OBJECTIVE: To evaluate the relationship between the regulatory factors in G1 phase of cell cycle and the cacrinogenesis of the trophoblastic cells. METHODS: The expressions of p16, cyclin-dependent kinase 4 (CDK4), proliferation cell nuclear antigen (PCNA) proteins in 18 cases of trophoblastic tumors, 30 cases of hydatidiform mole and 30 cases of normal villi were studied by immunohistochemical methods. RESULTS: The expressions of p16 protein between malignant trophoblastic tumors and normal villi were significantly different (P < 0.05). PCNA positive rate in p16 positive samples were markedly lower than that in negative samples (P < 0.05). The expressions of CDK4 among normal villi, hydatiform mole and trophoblastic tumors were not significantly different. Patients with positive p16 expression had a higher 3 year survival rate. CONCLUSION: p16 protein may inhibit trophoblastic cells proliferation, and p16 gene mutation may be an important factor in carcinogenesis of trophoblastic cells and proliferation out of control. P16 protein expression examination is helpful in prediction of patients prognosis.

Choriocarcinoma↗

[New aspects of diagnosis, treatment and follow-up of trophoblastic tumours (author's transl)].

Diagnosis, treatment and follow-up of gestational trophoblastic tumours has become more efficient through the introduction of new methods like angiography, computer tomography and, especially, the determination of specific chorionic gonadotrophin. Exact diagnosis, with differentiation of high- and low-risk patients allows an individual approach to treatment. The results of these new diagnostic and therapeutic methods were studied in a department with a relatively high incidence of gestational trophoblastic disease in a European region, where trophoblastic tumours are generally rare. (Since 1971 16 cases of trophoblastic tumour and 68 patients with hydatidiform mole were treated in the department of Obstetrics and Gynaecology, University of Graz.) Schedules were drawn up for the diagnosis, classification of risk and for treatment. This may help to get good results and to prevent errors in the future. Long-term determination of HCG beta in the serum and also comparative follow-up of LH and HCG in urine led to the formulation of further characteristics of gonadotrophin secretion after hydatidiform mole and treatment of trophoblastic tumours. On the basis of the results a regimen has been formulated which seems to be optimal for the detection of tumour after hydatidiform mole and for the registration of the effect of treatment in case of trophoblastic tumour.

Adult↗

Trophoblastic neoplasia in an African urban population.

A clinical study of trophoblastic neoplasia in a Nigerian population in Lagos over a four-year period is reported. A high incidence of one in 379 deliveries for benign trophoblastic tumor and one in 846 deliveries for malignant tumor was found. Seventeen percent of benign trophoblastic tumors in this series progressed to the malignant type, but malignant trophoblastic tumor was preceded by the benign type (hydatidiform mole) in 46 percent of cases. The anterior vaginal wall is a common site for metastases of malignant trophoblastic neoplasia and, in one patient, the lesion progressed further to form a vesicovaginal fistula. While the management of benign disease was conservative, all cases of malignant trophoblastic neoplasia received chemotherapy.

Adolescent↗

[Placental site trophoblastic tumor. Morphology, differential diagnosis and prognosis].

A placental-site trophoblastic tumor is a rare neoplasia that is derived from the cells of the intermediate trophoblast. Morphological, biochemical, and Doppler ultrasound findings are presented regarding differential diagnosis using material from three recent cases. Essentially, placental-site trophoblastic tumors can be diagnosed if infiltration of the myometrium is seen by a monomorphic trophoblastic proliferation that is not interrupted by decidual cells. Necrosis and hemorrhages are not features of placental-site trophoblastic tumors. However, there is a peculiar behavior towards the uterine vasculature as spiral arteries are dilated and transformed the same way as occurs at the site of physiological implantation of pregnancy. It appears that as a result of this phenomenon there is a characteristic finding in ultrasound. Examination of this type of tumor demonstrates cystic spaces that can be defined as blood vessels by their Doppler signal. In two of the three cases a hysterectomy was performed, and criteria for the assumption of malignant placental-site tumors are therefore presented. However, only the mitosis rate seems to possess some predictive value.

Adult↗

METTL14 alleviates pyroptosis of placental trophoblasts in gestational diabetes mellitus through the lncRNA MEG8/WNT7A axis via m6A modification.

Gestational diabetes mellitus (GDM) is a pregnancy complication associated with abnormal placental trophoblast function. Pyroptosis has been implicated in GDM pathogenesis, yet the role of m6A modification in this process remains unclear. We hypothesized that METTL14 regulates trophoblast pyroptosis through m6A-dependent modulation of the lncRNA MEG8/WNT7A axis. This study investigated the mechanism of METTL14 in pyroptosis of placental trophoblasts in GDM. HG-treated HTR8/SVneo cells were used as a cell model. METTL14, WNT7A, and lncRNA MEG8 expression was detected by RT-qPCR and western blot. Placental damage, cell injury, and pyroptosis markers were assessed. YTHDF2-mediated m6A enrichment on lncRNA MEG8, the interaction between lncRNA MEG8 and EZH2, and H3K27me3 enrichment on the WNT7A promoter were analyzed. Results showed that lncRNA MEG8 was upregulated, while METTL14 and WNT7A were downregulated. METTL14 overexpression reduced placental damage and trophoblast pyroptosis. Mechanistically, METTL14 suppressed lncRNA MEG8 expression through YTHDF2-mediated m6A methylation. Reduced lncRNA MEG8 decreased EZH2 recruitment to the WNT7A promoter, lowered H3K27me3 levels, and consequently promoted WNT7A expression. Rescue experiments confirmed that lncRNA MEG8 overexpression or WNT7A knockdown attenuated the suppressive effect of METTL14 on pyroptosis. In conclusion, METTL14 acts as an upstream regulator that inhibits trophoblast pyroptosis and ameliorates GDM-induced damage through the lncRNA MEG8/WNT7A axis via YTHDF2-mediated m6A modification, highlighting METTL14 as a potential therapeutic target.

Humans↗

Ectopic expression of DNMT3L in human trophoblast stem cells restores features of the placental methylome.

The placental DNA methylation landscape is unique, with widespread partially methylated domains (PMDs). The placental "methylome" is conserved across mammals, a shared feature of many cancers, and extensively studied for links with pregnancy complications. Human trophoblast stem cells (hTSCs) offer exciting potential for functional studies to better understand this epigenetic feature; however, whether the hTSC epigenome recapitulates primary trophoblast remains unclear. We find that hTSCs exhibit an atypical methylome compared with trophectoderm and 1st trimester cytotrophoblast. Regardless of cell origin, oxygen levels, or culture conditions, hTSCs show localized DNA methylation within transcribed gene bodies and a complete loss of PMDs. Unlike early human trophoblasts, hTSCs display a notable absence of DNMT3L expression, which is necessary for PMD establishment in mouse trophoblasts. Remarkably, we demonstrate that ectopic expression of DNMT3L in hTSCs restores placental PMDs, supporting a conserved role for DNMT3L in de novo methylation in trophoblast development in human embryogenesis.

Humans↗

Activation of mitogen-activated protein kinase is required for migration and invasion of placental site trophoblastic tumor.

Placental site trophoblastic tumor (PSTT) is a gestational neoplasm derived from the extravillous (intermediate) trophoblast of the implantation site. PSTT is characterized by a highly invasive phenotype, but the molecular mechanisms are poorly understood. In this report, we demonstrate that PSTTs expressed the activated (phosphorylated) form of mitogen-activated protein kinase (MAPK) in 84% of cases, whereas the normal extravillous trophoblastic cells did not. To characterize the role of MAPK activation in PSTT, we established the first PSTT cell culture, IST-2, from a surgically resected PSTT. IST-2 cells expressed HLA-G and Mel-CAM but not E-cadherin, an immunophenotype characteristic of PSTT. IST-2 cells were highly motile and invasive in culture as compared to choriocarcinoma JEG-3 cells and normal extravillous trophoblastic cells. Based on wound assay, time-lapse videomicroscopy for cell tracking, and invasion chamber assays, we found that the motility and invasion of IST-2 cells were significantly reduced (P<0.01) after treatment with the MEK inhibitors CI-1040 and PD 59089, which prevent activation of MAPK. In contrast, neither compound had any effect on normal extravillous trophoblastic cells or JEG-3 cells. In conclusion, our findings demonstrate a functional role of MAPK activation in the motility and invasion of PSTT.

Benzamides↗

Malignant potential, major histocompatibility complex antigen expression, and genomic imprinting of rat trophoblast cell lines.

Invasive growth, variation in major histocompatibility complex antigen expression, and genomic imprinting are important properties of both trophoblast cells and malignant tumors. This study, undertaken to address these three issues, used cultured trophoblast cell lines derived from Day 11/12 rat placentas of all mating combinations of the DA and WF inbred strains. In addition, genomic imprinting was also examined in intact rat placentas from Days 11-19. There was no correlation in trophoblast cells between class I antigen expression, DNA content, and cell ploidy on the one hand and oncogenic potential on the other hand. The constitutive suppression of class II antigens in the trophoblast cells could not be abrogated by treatment with interferon-gamma, whereas such treatment always maximally induced class I antigen expression regardless of the initial resting levels. The trophoblast cells at Day 11/12 expressed both maternal and paternal class I antigens, and studies in whole placental tissues showed that the imprinting of the maternal class I antigens was manifested by a decreased level of expression rather than an absence of expression. Thus, genomic imprinting in the rat placenta is a quantitative, rather than an all-or-none, phenomenon.

Animals↗

Expression of e-cadherin and beta-catenin in trophoblastic tissue in normal and pathological pregnancies.

E-cadherin and beta-catenin are cell-cell adhesion molecules, which are thought to play an important role in trophoblastic differentiation and remodelling during gestation. Their expression may be altered in pathological conditions with trophoblastic invasion. In this study, we used immunohistochemical methods to study the pattern of expression of E-cadherin and beta-catenin in villous trophoblastic tissue in normal and pathological pregnancies. In villous trophoblastic tissue, E-cadherin had a membranous distribution, whereas beta-catenin had a mixed-membranous and granular cytoplasmic distribution. The levels of expression of E-cadherin and beta-catenin correlated with each other. From first to third trimesters, the expression of both E-cadherin and beta-catenin showed a decreasing trend. In preeclampsia, there was an up-regulation of E-cadherin and beta-catenin expression. In placenta accreta, the level of expression of both did not differ from that in normal third-trimester placenta. In gestational trophoblastic diseases, there was a general trend of down-regulation of both E-cadherin and beta-catenin. Altered expression of E-cadherin and beta-catenin may play a role in the development of normal and pathological placentas.

Cadherins↗