Methylation status and expression of E-cadherin and cadherin-11 in gestational trophoblastic diseases

Placental T-Cadherin Correlates With Trophoblastic Invasion Anomalies: Placenta Percreta and Fetal Growth Restriction

In this study, we compared the placental T-cadherin staining intensity of pregnant women with placenta percreta (PP) and asymmetrical fetal growth restriction (FGR) compared with healthy control pregnancies. Placental T-cadherin levels of the placenta of 86 pregnant women in total, 25 with FGR, 30 with healthy pregnant subjects, and 31 with PP, were examined using monoclonal anti-T-cadherin (CDH13) antibody for immunohistochemical examination. In immunohistochemistry, H -scores were used for each group to compare the expression of T-cadherin in extravillous trophoblast (EVT) cells. T-cadherin H -score of EVTs was highest in the FGR group and the lowest in the PP group. The difference in H -score between the FGR group and the control group was not statistically significant ( P =0.344). The difference between the PP group and the other 2 groups was significant ( P <0.0001). Multivariable linear regression analysis with a stepwise elimination method was performed in order to identify demographic and clinical parameters with significant effects on the T-cadherin H -score of EVTs. The estimation results identified only the disease group as a significant predictor of the H -score of EVTs ( R2 =0.340, P <0.0001). The highest T-cadherin H -score of EVTs was found in the FGR group and the lowest in the PP group. The low T-cadherin H-score values in the PP group suggest that low T-cadherin EVTs may be associated with increased placental invasion. Likewise, despite the statistical insignificance, a higher T-cadherin H -score of EVTs in FGR compared with controls implies a decreased invasiveness of the placenta in FGR.

Relationship between serum cadherin 6 and 11 levels and severe and early-onset preeclampsia: A pilot study

Objective:

Preeclampsia is a highly morbid disease of placental origin, life-threatening condition for both a pregnant woman and her fetus. Cadherin 6 and 11 are adhesion molecules that play an important role in trophoblastic development and placentation. In our study, we investigated the change in serum cadherin 6 and 11 levels in pregnant women with preeclampsia.

Materials and Methods:

Pregnant women with preeclampsia were selected and compared with healthy women (as a control group) for a one-year study. The serum alanine aminotransferase, aspartate aminotransferase, and cadherin levels 6 and 11 of participants were analyzed and compared.

Results:

A total of 189 pregnant women were subdivided into 2 groups as preeclamptic (n=94) and women with healthy pregnancy (n=95). The cadherin 6 and cadherin 11 levels of the preeclamptic patients were significantly higher than those in the control group (p=0.001), and they were found to be significantly higher mainly in patients with early-onset and severe preeclampsia group (p=0.001). The cut-off cadherin 6 and 11 values for severe preeclampsia were found as 98.174 ng/mL and 1.92 ng/mL; with sensitivity of 88.3% and 84% respectively (p=0.001).

Conclusion:

The data analysis showed elevated serum cadherin 6 and 11 levels associated with the severity and early onset of pre-eclampsia. Serum cadherin 6 and 11 levels can be a candidate marker for the prediction of preeclampsia.

Gestational trophoblastic neoplasms (GTNs) do not display epithelial-to-mesenchymal transition (EMT) features

Although epithelial-to-mesenchymal transition (EMT) has been described in the development of complete hydatidiform moles and the invasion of the maternal decidua by trophoblasts during normal human placentation, its implication in gestational trophoblastic neoplasm (GTN) without villi is totally unknown. We studied the immunoexpression of EMT transcription factors (TWIST1, ZEB1, ZEB2), E-cadherin, and vimentin in 18 trophoblastic tumors and pseudo-tumors. Weak nuclear TWIST1 immunostaining was seen in 5% to 10% of all trophoblastic cells, without ZEB1 and ZEB2 nuclear staining. Trophoblastic cells did not express vimentin, and the expression of E-cadherin was maintained in all cases, indicating the absence of EMT features in GTN.

DNA methylation profiling highlights the unique nature of the human placental epigenome

As the 'gateway' to the fetus, the placenta is subject to a myriad of environmental factors, each with the potential to alter placental epigenetic and gene expression profile. This can have direct consequences for the developing fetus and potentially even long-term health implications. As a result, interest in placental epigenetics generally, and changes occurring in placenta-associated disease, has intensified over recent years. This article will discuss the general features of placental DNA methylation and will describe current technologies for profiling genome-wide DNA methylation patterns in this tissue, the approaches to data analysis and some of the major findings from recent studies.

Establishment of a choriocarcinoma model from immortalized normal extravillous trophoblast cells transduced with HRASV12

Gestational choriocarcinoma is a malignant trophoblastic tumor. The development of novel molecular-targeted therapies is needed to reduce the toxicity of current multiagent chemotherapy and to treat successfully the chemoresistant cases. The molecular mechanisms underlying choriocarcinoma tumorigenesis remain uncharacterized, however, and appropriate choriocarcinoma animal models have not yet been developed. In this study, we established a choriocarcinoma model by inoculating mice with induced-choriocarcinoma cell-1 (iC³-1) cells, generated from HTR8/SVneo human trophoblastic cells retrovirally transduced with activated H-RAS (HRASV12). The iC³-1 cells exhibited constitutive activation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways and developed into lethal tumors in all inoculated mice. Histopathological analysis revealed that the tumors consisted of two distinct types of cells, reminiscent of syncytiotrophoblasts and cytotrophoblasts, as seen in the human choriocarcinoma. The tumors expressed HLA-G and cytokeratin (trophoblast markers) and hCG (a choriocarcinoma marker). Comparative analysis of gene expression profiles between iC³-1 cells and parental HTR8/SVneo cells revealed that iC³-1 cells expressed matrix metalloproteinases, epithelial-mesenchymal transition-related genes, and SOX3 at higher levels than parental trophoblastic cells. Administration of SOX3-specific short-hairpin RNA decreased SOX3 expression and attenuated the tumorigenic activity of iC³-1 cells, suggesting that SOX3 overexpression might be critically involved in the pathogenesis of choriocarcinoma. Our murine model represents a potent new tool for studying the pathogenesis and treatment of choriocarcinoma.

Downregulation of ASPP1 in gestational trophoblastic disease: correlation with hypermethylation, apoptotic activity and clinical outcome

Gestational trophoblastic disease encompasses a spectrum of trophoblastic lesions including true neoplasms such as choriocarcinomas and the potentially malignant hydatidiform moles, which may develop persistent disease requiring chemotherapy. ASPP1, a member of apoptosis-stimulating proteins of p53 (ASPPs), is a proapoptotic protein that can stimulate apoptosis through its interaction with p53. We evaluated the promoter methylation and expression profiles of ASPP1 in different trophoblastic tissues and its in vitro functional effect on two choriocarcinoma cell lines, namely JEG-3 and JAR. Significant downregulation of ASPP1 mRNA and protein levels was demonstrated in hydatidiform moles and choriocarcinomas, when compared with normal placentas by quantitative-PCR and immunohistochemistry. The ASPP1 mRNA level was significantly correlated with its hypermethylation status, evaluated with methylation-specific PCR, in placenta and gestational trophoblastic disease samples (P=0.024). Moreover, lower ASPP1 immunoreactivity was shown in hydatidiform moles that progressed to persistent gestational trophoblastic neoplasms than in those that regressed (P=0.045). A significant correlation was also found between expression of ASPP1 and proliferative indices (assessed by Ki67 and MCM7), apoptotic activity (M30 CytoDeath antibody), p53 and caspase-8 immunoreactivities. An in vitro study showed that ectopic expression of ASPP1 could trigger apoptosis through intrinsic and extrinsic pathways as indicated by an increase in cleaved caspase-9 and Fas ligand protein expression. The latter suggests a hitherto unreported novel link between ASPP1 and the extrinsic pathway of apoptosis. Our findings suggest that downregulation of ASPP1 by hypermethylation may be involved in the pathogenesis and progress of gestational trophoblastic disease, probably through its effect on apoptosis.

Regulation of invasive growth: similar epigenetic mechanisms underpin tumour progression and implantation in human pregnancy

Malignant and trophoblastic cells share the capacity to migrate and invade surrounding tissues; however, trophoblast invasion during implantation is tightly regulated, whereas that associated with tumour progression is not. It is likely that similar mechanisms underlie the dynamic regulation of cell invasion and migration in both cases, and that these are based on epigenetic processes. This hypothesis is supported by recent results demonstrating that expression of the intercellular adhesion molecule E-cadherin, deregulation of which is associated with increased cell motility and invasive potential in cancer, is under epigenetic control in trophoblast cell lines. Further elucidation of the epigenetic pathways shared by trophoblasts and malignant cells is likely to lead to the identification of common diagnostic approaches for the early identification both of cancer and pathological pregnancies involving aberrant trophoblast invasion.