Impact of Th-17 Cytokines on the Regulation of Transporters in Human Placental Explants

Activated T helper 17 (Th-17) cytokines play a role in the pathophysiology of autoimmune and infectious diseases. While these diseases affect many women of childbearing age, little is known about the effect of these cytokines on placental transporters. As several pro-inflammatory cytokines impact the expression of ABC and SLC placental transporters, we hypothesized that these transporters may be similarly altered by elevated levels of circulating Th-17 cytokines. Cultured term human villous explants were treated with IL-17A, IL-22, or IL-23, alone or in combination. Samples were analyzed using qRT-PCR and Western blotting. The mRNA expression of OATP2B1 was significantly downregulated in explants by all individual cytokines and combination treatments, while decreased protein expression was seen with IL-23 and combination (p < 0.01). Combination treatment decreased the mRNA expression of BCRP and OAT4 but increased that of OCT3 (p < 0.01). Decreased accumulation of the OATP substrate, cascade blue, was seen in IL-23-treated choriocarcinoma JAr cells (p < 0.01). Elevated Th-17 cytokines, which are seen in infectious and autoimmune diseases, affect the expression and activity of OATP2B1, as well as mRNA expression of placental BCRP, OAT4, and OCT3. This dysregulation could impact the fetal exposure to endogenous and exogenous substrates.

Dysfunction of Shh signaling activates autophagy to inhibit trophoblast motility in recurrent miscarriage

In early pregnancy, the placenta anchors the conceptus and supports embryonic development and survival. This study aimed to investigate the underlying functions of Shh signaling in recurrent miscarriage (RM), a serious disorder of pregnancy. In the present study, Shh and Gli2 were mainly observed in cytotrophoblasts (CTBs), Ptch was mainly observed in syncytiotrophoblasts (STBs), and Smo and Gli3 were expressed in both CTBs and STBs. Shh signaling was significantly impaired in human placenta tissue from recurrent miscarriage patients compared to that of gestational age-matched normal controls. VEGF-A and CD31 protein levels were also significantly decreased in recurrent miscarriage patients. Furthermore, inhibition of Shh signaling impaired the motility of JAR cells by regulating the expression of Gli2 and Gli3. Intriguingly, inhibition of Shh signaling also triggered autophagy and autolysosome accumulation. Additionally, knockdown of BECN1 reversed Gant61-induced motility inhibition. In conclusion, our results showed that dysfunction of Shh signaling activated autophagy to inhibit trophoblast motility, which suggests the Shh pathway and autophagy as potential targets for RM therapy.

Soluble (pro)renin receptor increased by hypoxia maintains oxidative metabolism in trophoblasts

Elevated soluble (pro)renin receptor (s(P)RR) concentration in maternal blood is associated with gestational hypertension and preeclampsia. Placenta has abundant expression of (P)RR, and the binding of (P)RR with pyruvate dehydrogenase E1 beta subunit (PDHB) is reported to maintain oxidative metabolism. Thus, we hypothesized that placental hypoxia may increase (P)RR, and the increased (P)RR may preserve PDHB expression. Expression and functional analyses were performed using human placental trophoblast cells, mainly JAR cells. (P)RR co-immunoprecipitated and showed co-immunofluorescence with PDHB mainly in the mitochondria. Hypoxia treatment significantly increased intracellular s(P)RR protein expression, but secreted s(P)RR in the culture medium was decreased by hypoxia. Hypoxia treatment did not alter PDHB expression or activity in the basal condition, but when (P)RR was knocked down by siRNA, PDHB protein and activity were reduced by hypoxia. Acetyl-CoA, the product of PDH activity, was significantly reduced by hypoxia treatment with (P)RR siRNA. S(P)RR is generated from full-length PRR when cleaved by specific proteases. Protease inhibitor experiments suggested furin and site 1 protease as the enzymes generating s(P)RR in JAR cells, and only when treated by site 1 protease inhibitor, PF429242, PDHB protein showed a significant trend to decrease with hypoxia. In JAR cells, hypoxia increased intracellular s(P)RR, and (P)RR preserved the expression and function of PDHB during hypoxia. (P)RR may help maintain oxidative metabolism and efficient energy production during placental ischemia in hypertensive disorders of pregnancy.

miR-373-3p inhibits EMT via regulation of TGFβR2 in choriocarcinoma

Background: Previous studies have indicated that early metastasis is a major cause of mortality in patients with choriocarcinoma. However, what determines whether early metastasis of choriocarcinoma has occurred is unknown. The emerging role of miRNA in regulating cancer development and progression has been recognized. MiR-373 has been shown to play pivotal roles in tumorigenesis and metastasis. However, whether miR-373 functions to promote choriocarcinoma metastasis is not clear. The purpose of this study is to determine the function of miR-373-3p in the progression of this cancer. Methods: In this study, we first compared epithelial-to-mesenchymal transition (EMT)-related markers, which were inversely correlated with miR-373-3p expression, in trophoblast and choriocarcinoma cell lines. Using PCR and Western blot, upregulation of miR-373-3p was observed to inhibit EMT progression. Similarly, gain- and loss-of-function studies revealed that ectopic miR-373-3p overexpression inhibited the metastasis of choriocarcinoma cells. Results: Our results revealed that miR-373-3p acted as an EMT inhibitor in JEG-3 and JAR cells; this was due to its mediation of the TGF-β signalling pathway, which was responsible for EMT. Bioinformatic analysis demonstrated that miR-373-3p interacted with the 3' untranslated region of TGFβR2 mRNA, and then Western blot and dualluciferase reporter gene assays verified this interaction. Conclusions: Our findings suggest that miR-373-3p upregulation partly accounts for TGFβR2 downregulation and leads to a restraint of EMT and metastasis. MiR-373-3p may therefore serve as a valuable potential target in the treatment of choriocarcinoma.

Dysfunction of Shh signaling impaired trophoblast motility and autophagy is involved in poor placentation of recurrent miscarriage

Background: In early pregnancy, the placenta anchors the conceptus and supports embryonic development and survival. This study aimed to investigate the underlying functions of Shh signaling on recurrent miscarriage, an serious disorder of pregnancy. Methods: Immunofluorescence and immunohistochemistry were used to detect protein expression and its location in placental tissues. Quantitative real-time RT-PCR and Western blot analysis were performed to examine mRNA and protein levels, respectively. Lentiviruses expressing short hairpin RNA were used to knock down the target genes. Cell invasion and migration were performed by with or without Matrigel-coated transwell, respectively. Primary trophoblast migration was performed by villous explant assay. RNA-sequence was used to investigate the genes transcription profile. CCK-8 assay was used to evaluate cell viability. Flow cytometry was used to evaluate cell apoptosis. Results: Our results showed that Shh and Gli2 were mainly located in cytotrophoblasts (CTBs), Ptch was mainly located in syncytiotrophoblasts (STBs), while Smo and Gli3 were expressed in both CTBs and STBs. Compared to the gestational age-matched normal human placenta, the expression of Shh was significantly decreased in recurrent miscarriage. Furthermore, inhibition of Shh signaling impaired motility of JAR cells via regulating the expression of Gli2 and Gli3 to decrease AKT Ser473 phosphorylation, elevate E-cadherin and VEGFA. Intriguingly, inhibition of Shh signaling also enhanced autophagy and autolysosome. Additionally, knockdown BECN1 reversed the effect of Gant61 on motility inhibition. Conclusion: Our results indicated that dysfunction of Shh signaling impaired trophoblast motility, angiogenesis and activated autophagy in villous trophoblast, which would contribute to the pathophysiology of recurrent miscarriage.

Expression of ST6GalNAc1 and sialyl-Tn antigen enhances endometrial receptivity

BackgroundTo characterize molecular mechanism underlying the regulation of sialylated glycan expression and its roles for endometrial receptivity and embryo implantation. Here, we characterized the role of a truncated form of sialylated O-glycan, sialyl-Tn, for endometrial receptivity.MethodsThe transcriptomes of human endometrium at mid-secretory phase were analyzed by Bioinformatics. Changes in gene expression, protein, and signal pathway were measured using RT-PCR and Western blot. The cell adhesion assay was visualized using a fluorescent microscope. In peri-implantation phase of mice, the expression of leukemia inhibitory factor (LIF) and sialyl-Tn were confirmed using immunohistochemistry and immnofluorescence analysis. The effect of sialy-Tn expression on embryo implantation was estimated by in vitro fertilization and embryo transfer using mice.ResultsIn in silico analysis, expression of O-glycosylation genes, especially ST6GalNAc1, was significantly increased in the human uterus of mid-secretory phase. Overexpression of the ST6GalNAc1 gene in non-receptive human endometrial AN3CA cells enhances the attachment of trophoblastic JAr cells. In an animal study, the results clearly indicated that sialyl-Tn was expressed on the surface of the mid-secretory uterus. In addition, blockade of the receptor using free sialyl-Tn epitope diminished the implantation rates of intrauterine transferred murine embryos.ConclusionFrom these results, here we suggest that sialyl-Tn expression might be a novel factor regulating the endometrial receptivity for successful embryo implantation.

LncRNA GASAL1 Interacts with SRSF1 to Regulate Trophoblast Cell Proliferation, Invasion, and Apoptosis Via the mTOR Signaling Pathway

Long noncoding RNAs (lncRNAs) are crucial regulatory molecules involved in diverse biological processes and human diseases, including preeclampsia (PE). The lncRNA growth arrest associated lncRNA 1 (GASAL1) has been implicated in multiple malignant solid tumors and other diseases, while it is poorly known as the potential molecular mechanism of GASAL1 in PE. In this study, GASAL1 was significantly downregulated in the placentas’ of tissues from primipara with PE and trophoblast cell lines. Then, the upregulation of GASAL1 dramatically decreased proliferation and invasion and enhanced apoptosis in HTR-8/SVneo and JAR cells. Bioinformatics tool predicated that there is a potential interaction between GASAL1 and serine/arginine splicing factor 1 (SRSF1). RNA pull-down assays showed that GASAL1 directly binds with SRSF1 that could promote cell proliferation and invasion and suppress cell apoptosis. Further research showed that promoting effects of trophoblasts proliferation and invasion caused by co-transfecting GASAL1 and SRSF1 into HTR-8/SVneo and JAR cells were impaired by SRSF1 knockdown. Moreover, inhibition of the mammalian target of rapamycin (mTOR) activity by rapamycin influenced the effects of GASAL1 on cell proliferation, invasion, and apoptosis. Taken together, these findings suggest that lncRNA GASAL1 interacts with SRSF1 to regulate the proliferative, invasive, and apoptotic abilities of trophoblast cells via the mTOR signaling pathway.

Knockdown of lncRNA OGFRP1 Inhibits Proliferation and Invasion of JEG-3 Cells Via AKT/mTOR Pathway

Increasing evidence indicates the pivotal role of long noncoding RNAs in a variety of cancers, but there is limited focus on the link between long noncoding RNAs and gestational choriocarcinoma. This study aimed to examine the role of long noncoding RNA OGFRP1 in JEG-3 and JAR cells. Small interfering RNA was used to downregulate long noncoding RNA OGFRP1 level. Cell proliferation was measured by cell counting kit-8 and clone formation assays. Cell cycle and apoptosis were analyzed by flow cytometry. Cell invasion was examined by transwell assay. Protein expression was determined by Western blot. A double-effect inhibitor (BEZ235) that inhibits AKT and mTOR phosphorylation was used as a positive control. Knockdown of long noncoding RNA OGFRP1 significantly inhibited the proliferation of JEG-3 and JAR cells. Knockdown of long noncoding RNA OGFRP1 induced cell cycle arrest in G1 phase and apoptosis. On the other hand, knockdown of long noncoding RNA OGFRP1 inhibited the invasion of JEG-3 and JAR cells. Finally, knockdown of long noncoding RNA OGFRP1 resulted in the inactivation of AKT/mTOR signaling pathway. In addition, knockdown of long noncoding RNA OGFRP1 caused changes in the expression of intracellular cell cycle–related proteins and apoptosis-related proteins, including downregulation of CDK4, CDK6, Cyclin D1, Nusap1, and Bcl2 protein expression and upregulation of Bax protein expression. In conclusion, we found that downregulation of long noncoding RNA OGFRP1 inhibited cell proliferation, cell cycle progression, and invasion of JEG-3 and JAR cells and induced apoptosis through AKT/mTOR pathway. This study extends the understanding of the function of long noncoding RNA OGFRP1 in tumorigenesis, and these findings may be important for developing a potential therapeutic target for gestational choriocarcinoma therapy.

miR-373-3p inhibits EMT via regulation of TGFβR2 in choriocarcinoma

Background: Previous studies have indicated that early metastasis is a major cause of mortality in patients with choriocarcinoma. However, what determines whether early metastasis of choriocarcinoma has occurred is unknown. The emerging role of miRNA in regulating cancer development and progression has been recognized. MiR-373-3p has been shown to play pivotal roles in tumorigenesis and metastasis. However, whether miR-373-3p functions to promote choriocarcinoma metastasis is not clear. The purpose of this study is to determine the function of miR-373-3p in the progression of choriocarcinoma. Methods: In this study, we first compared EMT-related markers, which are inversely correlated with miR-373-3p expression, in trophoblast and choriocarcinoma cell lines. Using PCR and western blot, the upregulation of miR‑373‑3p was observed to inhibit EMT progression. Similarly, gain-and loss-of-function studies revealed that ectopic miR-373-3p overexpression inhibited the metastasis of choriocarcinoma cells. Results: Our results revealed that miR-373-3p functions as an inhibitor in JEG-3 and JAR cells; this is due to its mediation of the TGF-β signalling pathway, which is responsible for EMT. The bioinformatic analysis and dual‑luciferase reporter gene assays were employed to verify that miR‑373‑3p might interact with the 3' untranslated region of TGFβR2 mRNA. Further western blot results showed miR‑373‑3 preversed the increases of TGFβR2 and inhibited EMT. Conclusions: In light of our observations, miR‑373‑3p upregulation partly accounts for TGFβR2 downregulation and leads to a restraint of EMT and metastasis. MiR‑373‑3p may, therefore, serve as a valuable target in potential anticancer strategies to treat choriocarcinoma.