JEG-3 Choriocarcinoma Cells Research Articles

Human chorionic gonadotropin and its free β-subunit stimulate trophoblast invasion independent of LH/hCG receptor

Both paracrine and autocrine factors are involved in the regulation of trophoblast invasion. One of these factors is human chorionic gonadotropin (hCG), which stimulates trophoblast invasion. The stimulatory activity has especially been ascribed to a hyperglycosylated form of hCG (hCG-h) that is expressed in early pregnancy. We compared the stimulatory activities of different forms of hCG and its free β-subunit (hCGβ) on trophoblast invasion. hCG, hCG-h, hCGβ, and its hyperglycosylated form (hCGβ-h) stimulated the invasion of JEG-3 choriocarcinoma cells. The stimulatory effect of hCGβ was also confirmed with primary human trophoblasts. Down-regulation of the LH/hCG receptor by RNA-interference did not significantly reduce the effect of hCGβ and hCG on cell invasion. Increased invasion was associated with increased levels of MMP-2, MMP-9 and activity of uPA. Our findings suggest that hCG, hCGβ and their hyperglycosylated forms stimulate the invasion of trophoblast cells independent of the classical LH/hCG-receptor.

Proliferation and apoptosis of choriocarcinoma cell JEG-3 induced by VB2 and its in vitro mechanism

To investigate the effect of purified vitexin compound 2 (VB2), a noval lignanoid from the acetoacetate extract of Vitex negundo seed on the proliferation and apoptosis as well as the expression of mTOR and 4E-BP1 mRNA signal pathway in human choriocarcinoma JEG-3 cell lines in vitro. The inhibitory effect of different concentrations of VB2 on JEG-3 cells was examined by methyl thiazolyl tetrazolium (MTT) assay. Flow cytormetry was used to analyze the apoptosis after using different concentrations of VB2, and the expression of mTOR and 4E-BP1 mRNA was determined by RT-PCR. The inhibitory rate of JEG-3 cell growth which was cultured with different concentrations of VB2 (2.5, 5.0, 10.0, 20.0, 40.0, 80.0, and 160.0 μmol/L) for 24, 48, or 72 hours increased from (6.34±0.41)% to (85.89±0.81)%, and it was positively correlated with the dose and time of culture (P<0.05). VB2 at 5.0, 10.0, or 20.0 μmol/L increased the rate of JEG-3 cell apoptosis in vitro from (9.26±1.02)% to (35.55±1.24)% after 48 hour culture, which was in a dose dependent manner (P<0.05), while 5.0, 10.0, or 20.0 μmol/L of VB2 down-regulated the mRNA levels of mTOR and 4E-BP1 after 48 hour culture, which presented a significant negative correlation between VB2 and the mRNA levels of mTOR and 4E-BP1(P<0.05). VB2 can restrain the proliferation of choriocarcinoma cell JEG-3 and induce its apoptosis. This effect may be related to the inhibition of VB2 on the mRNA expression of JEG-3 cell mTOR and 4E-BP1.

Presence of Transcription Factor OCT4 Limits Interferon-tau Expression during the Pre-attachment Period in Sheep.

Interferon-tau (IFNT) is thought to be the conceptus protein that signals maternal recognition of pregnancy in ruminants. We and others have observed that OCT4 expression persists in the trophectoderm of ruminants; thus, both CDX2 and OCT4 coexist during the early stages of conceptus development. The aim of this study was to examine the effect of CDX2 and OCT4 on IFNT gene transcription when evaluated with other transcription factors. Human choriocarcinoma JEG-3 cells were cotransfected with an ovine IFNT (-654-bp)-luciferase reporter (-654-IFNT-Luc) construct and several transcription factor expression plasmids. Cotransfection of the reporter construct with Cdx2, Ets2 and Jun increased transcription of -654-IFNT-Luc by about 12-fold compared with transfection of the construct alone. When cells were initially transfected with Oct4 (0 h) followed by transfection with Cdx2, Ets2 and/or Jun 24 h later, the expression of -654-IFNT-Luc was reduced to control levels. OCT4 also inhibited the stimulatory activity of CDX2 alone, but not when CDX2 was combined with JUN and/or ETS2. Thus, when combined with the other transcription factors, OCT4 exhibited little inhibitory activity towards CDX2. An inhibitor of the transcriptional coactivator CREB binding protein (CREBBP), 12S E1A, reduced CDX2/ETS2/JUN stimulated -654-IFNT-Luc expression by about 40%, indicating that the formation of an appropriate transcription factor complex is required for maximum expression. In conclusion, the presence of OCT4 may initially minimize IFNT expression; however, as elongation proceeds, the increasing expression of CDX2 and formation of the transcription complex leads to greatly increased IFNT expression, resulting in pregnancy establishment in ruminants.

Abstract 4938: Free β-subunit of human chorionic gonadotropin stimulates choriocarcinoma cell invasion independent of LH/hCG receptor.

Abstract Human chorionic gonadotropin (hCG) is a heterodimer consisting of an α- and a β-subunit (hCGα and hCGβ) that are non-covalently linked. Intact hCG, but not free subunits, bind to the LH/hCG receptor. Expression of hCG and hCGβ has been observed in several cancers. Most trophoblastic tumors of placental and germ cell origin produce hCG, while many non-trophoblastic tumors, including bladder, renal and gastrointestinal cancers, often produce hCGβ, and increased serum concentrations of these are associated with adverse prognosis. hCG has been found to stimulate trophoblast invasion. The stimulatory activity has especially been ascribed to a hyperglycosylated form of hCG (hCG-h) expressed in early pregnancy. hCG-h is also a major form of hCG produced by choriocarcinoma and by testicular cancers, although tumor-derived hCG-h is often glycosylated differently than that produced by the placenta. We aimed to compare different forms of hCG in their stimulatory activities on the invasion of JEG-3 choriocarcinoma cells. Various forms of hCG and hCGβ were purified from urine of one patient with nonseminomatous testicular cancer, one with invasive molar disease, and pregnant women. Both hCG and hCGβ, and their hyperglycosylated forms stimulated the invasion of JEG-3 cells. However, cancer-derived hCG-h was more effective than “regular” hCG in stimulating the invasion. Down-regulation of the LH/hCG receptor by RNA-interference did not significantly reduce the effect of hCGβ and hCG on cell invasion. Increased invasion was associated with increased activity of MMP-2, MMP-9 and uPA in conditioned culture medium from JEG-3 cells. Our findings suggest that hCG and hCGβ stimulates the invasion of choriocarcinoma cells independent of the classical LH/hCG-receptor. Citation Format: Cheuk-Lun Lee, Philip CN Chiu, Laura Hautala, William SB Yeung, Ulf-Håkan Stenman, Hannu Koistinen. Free β-subunit of human chorionic gonadotropin stimulates choriocarcinoma cell invasion independent of LH/hCG receptor. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4938. doi:10.1158/1538-7445.AM2013-4938

Targeted nanoparticle delivery of doxorubicin into placental tissues to treat ectopic pregnancies.

Abnormal trophoblast growth can cause life-threatening disorders such as ectopic pregnancy, choriocarcinoma, and placenta accreta. EnGeneIC Delivery Vehicles (EDVs) are nanocells that can promote tissue-specific delivery of drugs and may be useful to medically treat such disorders. The objective of this study was to determine whether EDVs loaded with the chemotherapeutic doxorubicin and targeting the epidermal growth factor receptor (EGFR, very highly expressed on the placental surface) can regress placental cells in vitro, ex vivo, and in vivo. In female SCID mice, EGFR-targeted EDVs induced greater inhibition of JEG-3 (choriocarcinoma cells) tumor xenografts, compared with EDVs targeting an irrelevant antigen (nontargeted EDVs) or naked doxorubicin. EGFR-targeted EDVs were more readily taken up by human placental explants ex vivo and induced increased apoptosis (M30 antibody) compared with nontargeted EDVs. In vitro, EGFR-targeted EDVs administered to JEG-3 cells resulted in a dose-dependent inhibition of cell viability, proliferation, and increased apoptosis, a finding confirmed by continuous monitoring by xCELLigence. In conclusion, EGFR-targeted EDVs loaded with doxorubicin significantly inhibited trophoblastic tumor cell growth in vivo and in vitro and induced significant cell death ex vivo, potentially mediated by increasing apoptosis and decreasing proliferation. EDVs may be a novel nanoparticle treatment for ectopic pregnancy and other disorders of trophoblast growth.

Intranuclear Crosstalk between Extracellular Regulated Kinase1/2 and Signal Transducer and Activator of Transcription 3 Regulates JEG‐3 Choriocarcinoma Cell Invasion and Proliferation

Invasiveness of trophoblast and choriocarcinoma cells is in part mediated via leukemia inhibitory factor- (LIF-) induced activation of signal transducer and activator of transcription 3 (STAT3). The regulation of STAT3 phosphorylation at its ser727 binding site, possible crosstalk with intracellular MAPK signaling, and their functional implications are the object of the present investigation. JEG-3 choriocarcinoma cells were cultured in presence/absence of LIF and the specific ERK1/2 inhibitor (U0126). Phosphorylation of signaling molecules (p-STAT3 (ser727 and tyr705) and p-ERK1/2 (thr 202/tyr 204)) was assessed per Western blot. Immunocytochemistry confirmed results, but also pinpointed the location of phosphorylated signaling molecules. STAT3 DNA-binding capacity was studied with a colorimetric ELISA-based assay. Cell viability and invasion capability were assessed by MTS and Matrigel assays. Our results demonstrate that LIF-induced phosphorylation of STAT3 (tyr705 and ser727) is significantly increased after blocking ERK1/2. STAT3 DNA-binding capacity and cell invasiveness are enhanced after LIF stimulation and ERK1/2 blockage. In contrast, proliferation is enhanced by LIF but reduced after ERK1/2 inhibition. The findings herein show that blocking ERK1/2 increases LIF-induced STAT3 phosphorylation and STAT3 DNA-binding capacity by an intranuclear crosstalk, which leads to enhanced invasiveness and reduced proliferation.

Role of endoplasmic reticulum protein folding molecular chaperones in floxuridine-resistance choriocarcinoma JeG-3/FUDRA cell line

To investigate changes of protein expression profiles between human choriocarcinoma JeG-3 cell line and its floxuridine (FUDR)-resistant sub-line. The differentially expressed proteins were identified by using two dimension difference gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) approaches. Gene ontology (GO) analysis and Pathway analysis were used to screen the candidate proteins. The levels of the proteins in chemo-resistant sub-lines were validated by western blot. Ribonucleic acid interference (RNAi) was used to knockdown the expression of calreticulin (CALR) and (or) protein disulfide-isomerase A3 (PDIA3) respectively. Forty-six proteins spots were found to be significantly different in spot intensity by statistical analysis between chemo-resistance sub-line and parent cell line, of which 31 proteins were identified by MALDI-TOF-MS. Comparing to the parent cell lines, three endoplasmic reticulum (ER) protein folding molecular chaperones: CALR, PDIA3 and 78 000 glucose-regulated protein (GRP78) screened out were increased significantly in floxuridine-resistant sub-line and were verified by western blot. The resistance index decreased by knockdown the CALR and/or PDIA3 expression in FUDR-resistant sub-line 76.3% (36.7 ± 2.0 vs. 8.7 ± 3.1, P < 0.05) and 51.4% (36.7 ± 2.0 vs. 17.8 ± 1.2, P < 0.05) respectively. These ER protein folding molecular chaperones, CALR, PDIA3 and GRP78, may involved in the mechanism of FUDR-resistance choriocarcinoma.

Expression of survivin in human oocytes and preimplantation embryos

To determine whether [1] survivin is expressed in human oocytes and embryos; [2] embryos grown in vitro secrete survivin protein; and [3] survivin levels are correlated with embryo cleavage rates. Experimental. University-affiliated IVF clinic. Couples undergoing IVF-ET cycles. Conventional reverse transcriptase-polymerase chain reaction (PCR), real-time PCR, immunohistochemistry, Western blot on oocytes, embryos and control choriocarcinoma JEG-3 cells, and ELISA analysis of conditioned culture media. Detection of survivin mRNA and protein in oocytes and preimplantation embryos and in JEG-3 cancer cells. Detection of survivin concentrations in embryo culture media. Survivin mRNA and protein were expressed during human oocyte maturation, from germinal vesicle to metaphase II stage, and throughout embryo development, from pronuclear stage to blastocyst stage. Survivin was localized predominantly in the cytoplasm of all cells examined and in the oocytes on the chromatin of metaphase chromosomes and midbodies. Western blot analysis of human oocyte and cancer cell extracts detected a full-length (primary) survivin band of 16.5 kDa. Survivin was also detected in conditioned media samples from embryo cultures and showed a positive correlation with embryo cleavage rates. Our data have demonstrated for the first time that human oocytes/embryos not only express but also secret survivin, suggesting that survivin may play an important role in human oogenesis and embryogenesis.

Expression and Potential Role of GATA6 in Ruminant Trophoblasts during Peri-Implantation Periods

Abstract: Expression of GATA6 has been found during embryonic development in many mammalian species. In mouse embryonic development, GATA6 is a primitive endoderm (PrE) marker. However, the expression and effect of GATA6 in ruminant ungulates has not been well characterized. In this report, the expression of GATA6 mRNA was examined in the uteri of ruminants. GATA6 mRNA was detected in days 17, 20, and 22 (day 0=day of estrus) bovine conceptuses and in days 15, 17, and 21 ovine conceptuses. In both cases, GATA6 mRNA increased on day 22 or 21 after conceptus attachment to the uterine epithelium. GATA6 mRNA was also detected in bovine trophoblast CT-1 or F3 cells and ovine trophoblast oTr cells. In transient transfection analyses using the upstream region of the bovine IFNT gene (bIFNT, IFN-tau-c1), GATA6 overexpression was effective in the up-regulation of the bIFNT construct that had been transfected into human choriocarcinoma JEG3 or bovine ear-derived fibroblast EF cells. The observation in which GATA6 i...

StarD7 Knockdown Modulates ABCG2 Expression, Cell Migration, Proliferation, and Differentiation of Human Choriocarcinoma JEG-3 Cells

BackgroundStAR-related lipid transfer domain containing 7 (StarD7) is a member of the START-domain protein family whose function still remains unclear. Our data from an explorative microarray assay performed with mRNAs from StarD7 siRNA-transfected JEG-3 cells indicated that ABCG2 (ATP-binding cassette sub-family G member 2) was one of the most abundantly downregulated mRNAs.Methodology/Principal FindingsHere, we have confirmed that knocking down StarD7 mRNA lead to a decrease in the xenobiotic/lipid transporter ABCG2 at both the mRNA and protein levels (−26.4% and −41%, p<0.05, at 48 h of culture, respectively). Also a concomitant reduction in phospholipid synthesis, bromodeoxyuridine (BrdU) uptake and 3H-thymidine incorporation was detected. Wound healing and transwell assays revealed that JEG-3 cell migration was significantly diminished (p<0.05). Conversely, biochemical differentiation markers such as human chorionic gonadotrophin β-subunit (βhCG) protein synthesis and secretion as well as βhCG and syncytin-1 mRNAs were increased approximately 2-fold. In addition, desmoplakin immunostaining suggested that there was a reduction of intercellular desmosomes between adjacent JEG-3 cells after knocking down StarD7.Conclusions/SignificanceAltogether these findings provide evidence for a role of StarD7 in cell physiology indicating that StarD7 modulates ABCG2 multidrug transporter level, cell migration, proliferation, and biochemical and morphological differentiation marker expression in a human trophoblast cell model.

PAGE4 Positivity Is Associated with Attenuated AR Signaling and Predicts Patient Survival in Hormone-Naive Prostate Cancer

Aberrant activation of the androgen receptor (AR) plays a key role during prostate cancer (PCa) development and progression to castration-resistant prostate cancer (CR-PCa) after androgen deprivation therapy, the mainstay systemic treatment for PCa. New strategies to abrogate AR activity and biomarkers that predict aggressive tumor behavior are essential for improved therapeutic intervention. PCa tissue microarrays herein reveal that prostate-associated gene 4 (PAGE4), an X-linked cancer/testis antigen, is highly up-regulated in the epithelium of preneoplastic lesions compared with benign epithelium, but subsequently decreases with tumor progression. We show that AR signaling is attenuated in PAGE4-expressing cells both in vitro and in vivo, most likely via impaired androgen-induced AR nuclear translocation and subsequently reduced AR protein stabilization and phosphorylation at serines 81 and 213. Consistently, epithelial PAGE4 protein levels inversely correlated with AR activation status in hormone-naive and CR-PCa clinical specimens. Moreover, PAGE4 impaired the development of CR-PCa xenografts, and strong PAGE4 immunoreactivity independently predicted favorable patient survival in hormone-naive PCa. Collectively, these data suggest that dysregulation of epithelial PAGE4 modulates AR signaling, thereby promoting progression to advanced lethal PCa and highlight the potential value of PAGE4 as a prognostic and therapeutic target.

Comparative analysis of the invasion-associated genes expression pattern in first trimester trophoblastic (HTR-8/SVneo) and JEG-3 choriocarcinoma cells

Several cellular models of trophoblast have been proposed to understand their invasion. We had reported that JEG-3 and HTR-8/SVneo cells show differential invasive behavior in response to IL-11 treatment. So, the present study aims to compare the expression of invasion-associated molecules in these two cell lines by performing cDNA microarray followed by quantitative RT-PCR. We have observed that HTR-8/SVneo cells have significantly higher invasiveness than JEG-3 cells, which might be due to higher expression of proteases and signaling intermediates of JAK/STAT and MAPK signaling pathways. Like extravillous trophoblasts (EVTs), a higher expression of functionally significant proteases like MMP1, MMP2, MMP9, PLAU etc in HTR-8/SVneo cells, project them as a close mimic of EVTs under in vitro conditions.

The effect of triclosan on hormone secretion and viability of human choriocarcinoma JEG-3 cells

Triclosan is an antimicrobial agent frequently used in pharmaceuticals and personal care products. We analyzed triclosan for its action on placental secretion of progesterone, estradiol and human chorionic gonadotropin in vitro in the JEG-3 cells. We also investigated its action on cell viability, proliferation and apoptosis. The JEG-3 cells were cultured with increasing doses of triclosan (1×10−9–1×10−4M) for 24, 48 and 72h. Triclosan was found to increase estradiol and progesterone secretion after short- and long-term exposure. The stimulatory effect was observed up to 10μM after short- and long-term exposure to triclosan. In addition, triclosan caused an adverse effect on β-hCG secretion. The highest doses of triclosan (50 and 100μM) showed a strong cytotoxic effect. Anti proliferative and pro-apoptotic effects were also observed. Overall, this study demonstrates that triclosan may indirectly disrupt steroidogenesis which may, in turn, affect placental development and consequently fetal growth.

The double life of MULE in preeclamptic and IUGR placentae

The E3 ubiquitin ligase MULE (Mcl-1 Ubiquitin Ligases E3) targets myeloid cell leukemia factor 1 (Mcl-1) and tumor suppressor p53 for proteasomal degradation. Although Mcl-1 and p53 have been implicated in trophoblast cell death in preeclampsia (PE) and intrauterine growth restriction (IUGR), the mechanisms regulating their expression in the human placenta remains elusive. Herein, we investigated MULE's involvement in regulating Mcl-1 and p53 degradation during normal and abnormal (PE, IUGR) placental development. MULE expression peaked at 5–7 weeks of gestation, when oxygen tension is low and inversely correlated with that of Mcl-1 and p53. MULE efficiently bound to Mcl-1 and p53 and regulated their ubiquitination during placental development. Exposure of first trimester villous explants to 3% O2 resulted in elevated MULE expression compared with 20% O2. Low-oxygen-induced MULE expression in JEG3 choriocarcinoma cells was abolished by hypoxia-inducible factor (HIF)-1α siRNA. MULE was overexpressed in both PE and IUGR placentae. In PE, MULE preferentially targeted p53 for degradation, allowing accumulation of pro-apoptotic Mcl-1 isoforms. In IUGR, however, MULE targeted pro-survival Mcl-1, allowing p53 to accumulate and exert its apoptotic function. These data demonstrate that oxygen regulates Mcl-1 and p53 stability during placentation via HIF-1-controlled MULE expression. The different preferential targets of MULE in PE and IUGR placentae classify early-onset PE and IUGR as distinct molecular pathologies.

Possible aryl hydrocarbon receptor-independent pathway of 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced antiproliferative response in human breast cancer cells

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a ligand with high affinity for the aryl hydrocarbon receptor (AhR). It suppresses 17β-estradiol (E2)-induced cell proliferation in human breast cancer cells. Although it has been theorized that the AhR is involved in TCDD-induced antiestrogenic activity and antiproliferation in human breast cancer cells, some evidence suggests that these activities of chlorinated aromatic compounds also occur by AhR-independent pathways. Here, we investigated the possibility of TCDD-induced antiproliferative responses in human breast cancer cells through AhR-independent pathways. Compared with that in vehicle-treated controls, DNA synthesis was significantly suppressed in MCF-7 cells and ZR75-1 cells treated with TCDD at a very low concentration (0.01nM), whereas that in human ovarian carcinoma OVCAR3 cells, human cervical carcinoma HeLa cells and human choriocarcinoma JEG-3 cells was unaffected, even by exposure to 10nM TCDD. The suppression induced by TCDD was not associated with the estrogen receptor α-signaling pathway. Another AhR agonist, 3,3′,4,4′,5-pentachlorobiphenyl, had no effect on DNA synthesis in MCF-7 cells at concentrations high enough to induce the transactivation function of the AhR. Furthermore, in MCF-7 cells, knockdown of the AhR by RNA interference had no effect on TCDD-induced antiproliferation. These findings suggest that the principal pathways of TCDD-induced antiproliferation in breast cancer cells are not AhR dependent.

Endothelin-1 Induces Endoplasmic Reticulum Stress by Activating the PLC-IP3 Pathway: Implications for Placental Pathophysiology in Preeclampsia

Recent evidence implicates placental endoplasmic reticulum (ER) stress in the pathophysiological characteristics of preeclampsia. Herein, we investigate whether endothelin (ET)-1, which induces Ca(2+) release from the ER, can induce placental ER stress. Loss of ER Ca(2+) homeostasis impairs post-translational modification of proteins, triggering ER stress-response pathways. IHC confirmed the presence of both ET-1 and its receptors in the syncytiotrophoblast. Protein levels and immunoreactivity of ET-1 and the endothelin B receptor (ETBR) were increased in preeclamptic samples compared with normotensive controls. JEG-3 and BeWo choriocarcinoma cells treated with ET-1 displayed an increase in ER stress markers. ET-1 induced phospho-activation of the ETBR. Treating cells with BQ788, an ETBR antagonist, or small-interfering RNA knockdown of the receptor inhibited induction of ER stress. ET-1 also stimulated p-phospholipase C (PLC)γ1 levels. By using inhibitors of PLC activation, U73122, and the inositol 1,4,5-triphosphate (IP(3)) receptor, xestospongin-C, we demonstrated that ET-1 induces ER stress via the PLC-IP(3) pathway. Furthermore, ET-1 levels increased in the syncytiotrophoblast of explants from normal placentas after hypoxia-reoxygenation in vitro. Conditioned medium from hypoxia-reoxygenation explants also contained higher ET-1 levels, which induced ER stress in JEG-3 cells that was abolished by an ET-1-neutralizing antibody. Collectively, the data show that ET-1 induced ER stress in trophoblasts via the ETBR and initiation of signaling through the PLC-IP(3) pathway, with the potential for autocrine stimulation.

The biological function of hyperglycosylated hCG

Hyperglycosylated human chorionic gonadotropin (hCG) is a variant of hCG made by cytotrophoblast cell. Here we examine the role of hyperglycosylated hCG in placenta growth and invasion. JEG-3 choriocarcinoma cells and term cytotrophoblast monolayer culture were prepared. The effect of supplemental hyperglycosylated hCG and hCG was investigated. Growth of these cells was examined by increase in cell number. Invasion was investigated using Matrigel basement membrane cells. The proportion of cell invading Matrigel was determined. Term cytotrophoblast cell and JEG-3 choriocarcinoma cells grew to 5 427±834 cells (109%) and 7 114±553 cells (142%). With the supplementation of hyperglycosylated hCG, they grew significantly wider to 7 633±177 cells (142%) and 10 315±1 477 cells (206%). With the supplementation of hCG they diminished to 4 227±769 cells (78%) and 5 620±657 cells (79%). Term cytotrophoblast cell and JEG-3 choriocarcinoma cells penetrated Matigel membranes to (40.0±10.0)% and (46.0±9.8)%. Hyperglycosylated hCG significantly enhanced penetration to (76.0±13.0)% and (84.0±6.6)%. hCG diminished penetration to (32.0±9.1)% and (32.0±4.5)%. Hyperglycosylated hCG enhances both cytotrophoblast growth and cytotrophoblast cell invasion. hCG minimally suppresses growth and invasion.

Secretion and transfer of the thyroid hormone binding protein transthyretin by human placenta

ContextThe thyroid hormone and retinol binding protein transthyretin (TTR) is synthesised by human trophoblasts. Polarised JEG-3 choriocarcinoma cells grown in bicameral chambers secrete TTR predominantly apically but also basally and these cells and human trophoblasts also take up TTR suggesting that there may be a placental TTR shuttle that participates in materno-fetal transfer of thyroid hormones and retinol. Objectives and methodsOur objective was to investigate TTR secretion into the maternal and fetal circuits of the ex vivo dually perfused placental lobule to confirm that placenta secretes TTR into the fetal circulation. We also investigated translocation of Alexa Fluor-594 labelled TTR from incubation medium into the fetal placental capillaries in early (14–15 weeks) and term placental villus explants. ResultsThe perfused placental lobule secretes TTR into the maternal and fetal circuits. Secretion in both circuits is linear with time and is predominantly into the maternal circuit (mean maternal/fetal ratio 99.4 ± 25.6). The mean data fitted well to a three compartment mathematical model (maternal circuit, placenta and fetal circuit, constant secretion of TTR and return of maternal circuit TTR to the placental compartment). Explants from early (14–15 weeks) and late (38–40 weeks) placentas translocated fluorescently labelled TTR from medium to villus (fetal) capillaries. ConclusionsOur results confirm that human placenta secretes TTR into maternal and fetal circulations and supports the hypothesis that placental TTR secreted into the maternal placental circulation can be taken up by trophoblasts and translocated to the fetal circulation, forming a TTR shuttle system. This may have important implications for materno-fetal transfer of thyroid hormones, retinol/retinol binding protein and xenobiotics (such as polychlorinated biphenyls) all of which bind to TTR.

Effects of the organophosphate insecticides phosmet and chlorpyrifos on trophoblast JEG-3 cell death, proliferation and inflammatory molecule production

Epidemiological data have associated environmental organophosphate insecticide (OP) exposure during pregnancy with fetal growth deficits. To better understand OP injury that may adversely affect pregnancy, we used the JEG-3 choriocarcinoma cell line, which provide a recognized in vitro model to study placental function. The effects of the OP phosmet (Pm) and chlorpyrifos (Cp) on JEG-3 cells viability, proliferation, cell cycle and inflammatory molecule production were evaluated. Both insecticides affected cellular viability in a concentration- and time-dependent manner, inducing apoptosis and decreasing [3H]-thymidine incorporation. However, only Pm reduced DNA synthesis independently of cellular death and decreased the cell percentage at the S-phase. Unlike apoptosis, TNFα production varied with the concentration tested, suggesting that other TNFα independent mechanisms might trigger cell death. No induction of the inflammatory molecule nitric oxide was detected. The mRNA levels of pro-inflammatory IL-6, IL-17 and the anti-inflammatory IL-13 cytokines were differentially modulated. These findings show that Pm and Cp generate a specific toxicity signature, altering cell viability and inducing an inflammatory cytokine profile, suggesting that trophoblasts may represent a possible target for OP adverse effects.

The impact of TGF-β1 on the mRNA expression of TβR I, TβR II, Smad4 and the invasiveness of the JEG-3 placental choriocarcinoma cell line

Human choriocarcinoma is one of the most aggressive malignant tumors characterized by early hematogenous spread to lung and brain tissues, and may be a cause of death in patients. Choriocarcinoma may occur following pregnancy and during implantation; however, trophoblastic invasion in human pregnancy is tightly regulated. The transforming growth factor-beta 1 (TGF-β1) has been suggested to play a role in controlling this process. In this study, we investigated the impact of TGF-β1 on invasion, as well as its sites of action in the TGF-β1/Smad pathway using a JEG-3 choriocarcinoma cell line. Following the treatment of cells with different doses of TGF-β1, cell invasion was observed. We also detected the expression of TGF-β receptor type I (TβR I) and TGF-β receptor type II (TβR II), Smad4, matrix metalloprotease (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 in JEG-3 cells. Our data demonstrated that TGF-β1 promoted the invasive capability of JEG-3 cells depending on the downregulation of TβR I, TβR II, Smad4 and the upregulation of MMP-9 and TIMP-1. These observations suggest that TGF-β1 may play a critical role in the initiation of the trophoblastic invasion process.