Overexpression of long noncoding RNA DUXAP8 inhibits ER-phagy through activating AKT/mTOR signaling and contributes to preeclampsia.

Preeclampsia (PE) is a life-threatening pregnancy-specific complication with controversial mechanisms and no effective treatment except delivery is available. Currently, increasing researchers suggested that PE shares pathophysiologic features with protein misfolding/aggregation disorders, such as Alzheimer disease (AD). Evidences have proposed defective autophagy as a potential source of protein aggregation in PE. Endoplasmic reticulum-selective autophagy (ER-phagy) plays a critical role in clearing misfolded proteins and maintaining ER homeostasis. However, its roles in the molecular pathology of PE remain unclear. We found that lncRNA DUXAP8 was upregulated in preeclamptic placentae and significantly correlated with clinical indicators. DUXAP8 specifically binds to PCBP2 and inhibits its ubiquitination-mediated degradation, and decreased levels of PCBP2 reversed the activation effect of DUXAP8 overexpression on AKT/mTOR signaling pathway. Function experiments showed that DUXAP8 overexpression inhibited trophoblastic proliferation, migration, and invasion of HTR-8/SVneo and JAR cells. Moreover, pathological accumulation of swollen and lytic ER (endoplasmic reticulum) was observed in DUXAP8-overexpressed HTR8/SVneo cells and PE placental villus trophoblast cells, which suggesting that ER clearance ability is impaired. Further studies found that DUXAP8 overexpression impaired ER-phagy and caused protein aggregation medicated by reduced FAM134B and LC3II expression (key proteins involved in ER-phagy) via activating AKT/mTOR signaling pathway. The increased level of FAM134B significantly reversed the inhibitory effect of DUXAP8 overexpression on the proliferation, migration, and invasion of trophoblasts. In vivo, DUXAP8 overexpression through tail vein injection of adenovirus induced PE-like phenotypes in pregnant rats accompanied with activated AKT/mTOR signaling, decreased expression of FAM134B and LC3-II proteins and increased protein aggregation in placental tissues. Our study reveals the important role of lncRNA DUXAP8 in regulating trophoblast biological behaviors through FAM134B-mediated ER-phagy, providing a new theoretical basis for understanding the pathogenesis of PE.

Comprehensive analysis of transcriptomic profiling of 5-methylcytosin modification in placentas from preeclampsia and normotensive pregnancies.

Increasing evidence suggests that RNA m5C modification and its regulators have been confirmed to be associated with the pathogenesis of many diseases. However, the distribution and biological functions of m5C in mRNAs of placental tissues remain unknown. we collected placentae from normotensive pregnancies (CTR) and preeclampsia patients (PE) to analyze the transcriptomic profiling of m5C RNA methylation through m5C RNA immunoprecipitation (UMI-MeRIP-Seq). we discovered that overall m5C methylation peaks were decreased in placental tissues from PE patients. And, 2844 aberrant m5C peaks were identified, of which respectively 1304 m5C peaks were upregulated and 1540 peaks were downregulated. The distribution of m5C peaks were mainly located in CDS (coding sequences) regions in placental tissues of both groups, but compared with the CTR group, the m5C peak in PE group before the stop code of CDS was significantly increased and even higher than the peak value after start code in CDS. Differentially methylated genes were mainly enriched in MAPK/cAMP signaling pathway. Moreover, the up-regulated genes with hypermethylated modification were enriched in the processes of hypoxia, inflammation/immune response. Finally, through analyzing the mRNA expression levels of m5C RNA methylation regulators, we found only DNMT3B and TET3 were significantly upregulated in PE samples than in control group. And they are not only negatively correlated with each other, but also closely related to those differentially expressed genes modified by differential methylation.Our findings provide new insights regarding alterations of m5C RNA modification into the pathogenic mechanisms of PE.

MiR-95-3p/EPM2A/MMP2 contributes to the pathogenesis of severe preeclampsia through the regulation of trophoblast biological behaviour.

OBJECTIVE: Preeclampsia (PE) is a maternal multisystem disease with an unclear mechanism. Data showed that MiR-95-3p promoted cell migration, invasion and proliferation, leading to the occurrence and development of many cancers, and placental trophoblasts and tumor cells had similar migration, invasion and proliferation abilities. Meanwhile we found that MiR-95-3p was differentially expressed in PE and normal placenta. Therefore, this article aimed to explore the biological function and mechanism of miR-95-3p in PE. METHODS: The expression of miR-95-3p in PE and normal placental tissue was explored by high-throughput sequencing and qRT-PCR. The effects of miR-95-3p on trophoblast migration, invasion, proliferation, angiogenesis and apoptosis were investigated by Transwell migration and invasion assays, cell viability assay, tube formation assay and flow cytometry in two trophoblast cell lines (HTR-8/SVneo and JAR). The miR-95-3p target gene EPM2A was identified and verified by unique identifier mRNA next-generation sequencing and dual-luciferase reporter gene experiments. Rescue experiments were conducted to investigate whether miR-95-3p regulated EPM2A to participate in trophoblast migration and invasion. Finally, the effects of miR-95-3p and EPM2A on the expression of angiogenic factors and inflammation-related factors were investigated by ELISA. RESULTS: We found that miR-95-3p was expressed at low levels in the placental tissue of patients with PE and was negatively correlated with EPM2A expression. In vitro upregulation of miR-95-3p and downregulation of EPM2A promote trophoblast migration, invasion and proliferation. Furthermore, EPM2A was confirmed as a target mRNA of miR-95-3p. Upregulation of EPM2A mitigated miR-95-3p-mediated promotion of trophoblast migration and invasion and vice versa. Finally, both miR-95-3p and EPM2A regulate the expression of trophoblast angiogenesis-related factors and inflammation-related factors. CONCLUSION: Our findings demonstrated that miR-95-3p promoted the migration and invasion of trophoblast cells by targeting EPM2A to inhibit the occurrence and development of PE.

Circulating chemerin levels in preeclampsia: a systematic review and meta-analysis.

BACKGROUND: Preeclampsia (PE) is a new-onset pregnancy-specific disorder with a high prevalence that leads to over 70 000 maternal and 500 000 foetal fatalities worldwide each year. The level of chemerin, a newly identified adipokine, is increased in diabetic and obese patients. Currently, there are several studies describing the relationship between maternal circulating chemerin levels and PE. Therefore, this study aimed to assess their association in pooled samples. METHODS: Four databases were systematically searched to identify potential studies that reported circulating chemerin levels in PE and normal pregnancy groups. Standardized mean differences (SMDs), 95% confidence intervals (CIs), and 95% prediction intervals (PIs) were calculated using a random-effects meta-analysis. The probability of heterogeneity was also investigated by sensitivity analysis, subgroup analysis, and meta-regression. RESULTS: Thirteen studies in 11 articles with a total of 860 PE patients and 1309 women with normal pregnancies met the inclusion criteria. The results of the meta-analysis revealed that circulating chemerin, which levels in PE patients were considerably higher than those in controls (SMD = 1.39, 95% CI: 1.02, 1.77, 95% PI: -0.07, 2.86). Moreover, sensitivity analysis determined that the outcomes of the overall pooled results were not affected after the elimination of any study. Notably, subgroup analysis demonstrated a similar expression pattern irrespective of geographic location, severity, timing of sampling, and sample size. Last, there were no factors that significantly impacted the overall estimate, according to meta-regression. CONCLUSIONS: This meta-analysis is the first to assess circulating chemerin levels in PE patients. The findings indicate that circulating chemerin levels may be a potential marker to diagnose PE.

The long noncoding RNA TARID regulates the CXCL3/ERK/MAPK pathway in trophoblasts and is associated with preeclampsia.

BACKGROUND: The widely accepted explanation of preeclampsia (PE) pathogenesis is insufficient trophoblast invasion and impaired uterine spiral artery remodeling. However, the underlying molecular mechanism remains unclear. METHODS: We performed transcriptome sequencing on placentas of normal and PE patients and identified 976 differentially expressed long noncoding RNAs (lncRNAs). TCF21 antisense RNA inducing demethylation (TARID) was one of the most significantly differentially expressed lncRNAs and was negatively correlated with the systolic and diastolic blood pressure in PE patients. Furthermore, we verified the effect of TARID on the biological behavior of trophoblasts and performed UID mRNA-seq to identify the effectors downstream of TARID. Then, co-transfection experiments were used to better illustrate the interaction between TARID and its downstream effector. RESULTS: We concluded that the downregulation of TARID expression may inhibit trophoblast infiltration and spiral artery remodeling through inhibition of cell migration, invasion, and tube formation mediated through the CXCL3/ERK/MAPK pathway. CONCLUSIONS: Overall, these findings suggested that TARID may be a therapeutic target for PE through the CXCL3/ERK/MAPK pathway.

The Association Between Season and Hypertensive Disorders in Pregnancy: a Systematic Review and Meta-analysis.

There is increasing and inconsistent evidence of a relationship between hypertensive disorders in pregnancy (HDPs) and season of delivery or conception. In this systematic review and meta-analysis, we assessed the association between season and HDPs. The review protocol was registered in PROSPERO (CRD42021285539). Four databases, the Cochrane Library, PubMed, EMBASE, and Web of Science, were searched until September 29th, 2021. Two authors extracted data independently and used the Newcastle-Ottawa quality assessment scale (NOS) to evaluate study quality. A random effects model and the Mantel-Haenszel method were used to calculate pooled Odds ratios (ORs) and 95% confidence intervals (95% CIs). Subgroup analyses and sensitivity analyses were performed to find the source of heterogeneity and Begg's funnel plot and Egger's test were used to check for the risk of publication bias. Finally, twenty articles were included in the systematic review, and 11 articles were included in the meta-analysis. The quantitative analysis of the association between delivery season and HDPs showed that the odds of HDPs was higher in women who delivered in winter than in those who delivered in summer (OR = 1.18, 95% CI 1.02-1.38, P < 0.001) and all other seasons (OR = 1.17, 95% CI 1.03-1.34, P < 0.001). In the qualitative analysis of the association between conception season and HDPs, four of seven studies suggested that women who conceived in summer had a higher risk of HDPs than those who conceived in other seasons. Based on the evidence to date, we found weakly positive relationships between HDPs and summer conception and winter delivery.

BCAM Deficiency May Contribute to Preeclampsia by Suppressing the PIK3R6/p-STAT3 Signaling.

BACKGROUND: Preeclampsia is a pregnancy syndrome that may utilize multiple pathogenic mechanisms. Insufficient trophoblast invasion and impaired uterine spiral artery remodeling are believed to be the pathological basis; yet the underlying mechanisms remain largely unclear. METHODS: The placental BCAM (basal cell adhesion molecule) expression and important clinical indicators were detected and correlation analysis was performed. MiRNAs directly targeting BCAM were predicted and further verified by dual-luciferase reporter gene, and the downstream molecular mechanisms of BCAM were investigated in both HTR-8/SVneo and JAR cells. In addition, pregnant/nonpregnant rats were treated with adenoviruses containing BCAM shRNA genes (Ad-shBCAM) on gestational 9.5 days to detect the preeclamptic features. RESULTS: The BCAM is highly expressed on the trophoblast membrane and decreased in the preeclamptic placentae. In HTR-8/SVneo and JAR cells, BCAM knockdown inhibited trophoblast proliferation, migration, and invasion, and suppressed phosphorylation on Y705 of STAT3 dependent on the downregulation of PIK3R6. Moreover, miR-199a-5p mediated the degradation of BCAM and also inhibited trophoblast proliferation, migration, and invasion. In vivo, BCAM deficiency induced a preeclampsia-like phenotype included elevated systolic blood pressure, proteinuria, impaired morphology and function of multiple organs (placenta, liver, and kidney), and fetal growth restriction. The expression of placenta BCAM/PIK3R6/p-STAT3 signaling was also downregulated in this preeclampsia rat model. CONCLUSIONS: MiR-199a-5p mediated-BCAM deficiency contributes to the suppression of trophoblast proliferation, migration, and invasion by inhibiting PIK3R6/p-STAT3 signaling, which may lead to poor placentation and result in preeclampsia-like phenotypes. Our study provides a new academic perspective on the pathogenesis of preeclampsia.

Upregulation of lncRNA HITT promotes cell apoptosis by suppressing the maturation of miR-602 in gastric cancer.

It has been reported that HITT can inhibit colon cancer. However, the role of HITT in gastric cancer (GC) is unknown. Our preliminary sequencing data revealed the altered expression of HITT in GC and its close correlation with miR-602, suggesting the involvement of HITT and its potential interaction with miR-602 in GC. This study explored the role of HITT and its crosstalk with miR-602 in GC. In this study, the expression of HITT, premature and mature miR-602 in paired GC and normal tissues (62 patients) was detected by RT-qPCR. RNA pull-down assay was performed to evaluate the direct interaction between HITT and mature miR-602. The subcellular location of HITT was assessed by nuclear fractionation assay. The role of HITT in regulating miR-602 maturation was explored by overexpression assay. Cell apoptosis was analyzed by flow cytometry. Our data illustrated that HITT was highly upregulated and mature miR-602 was downregulated in GC. No alteration in premature miR-602 in GC was observed. HITT was located in both nucleus and cytoplasm, and it can directly interact with miR-602. In addition, overexpression of HITT in GC cells increased the expression levels of mature miR-602 but not premature miR-602. Overexpression of HITT further increased GC cell apoptosis and suppressed the role of miR-602 in inhibiting GC cell apoptosis. In conclusion, HITT may promote GC cell apoptosis by suppressing the maturation of miR-602.

SIRT3 deficiency affects the migration, invasion, tube formation and necroptosis of trophoblast and is implicated in the pathogenesis of preeclampsia.

INTRODUCTION: Sirtuin 3 (SIRT3) plays a key role in many diseases by regulating cell necroptosis and biological behavior. However, the exact role of SIRT3 in preeclampsia remains unclear. METHODS: The expression of SIRT3 and necroptosis biomarkers, including receptor-interacting protein kinase 1 (RIPK1), RIPK3 and phosphorylated mixed lineage kinase domain-like protein (p-MLKL), in the placentas of 20 healthy pregnancy controls and 20 preeclampsia patients was evaluated by immunofluorescence, quantitative real-time PCR and Western blot. The effect of hypoxia on trophoblast necroptosis was examined in HTR8/SVneo cells. The effects of SIRT3 on the necroptosis, invasion, migration, and tube formation of HTR8/SVneo cells were investigated by transfection with siRNA lentiviruses that silenced or overexpressed SIRT3. RESULTS: The expression of SIRT3 was decreased and the expression of RIPK1, RIPK3 and p-MLKL was increased in placental trophoblasts from preeclampsia patients compared to those from healthy pregnancy controls. Hypoxia increased RIPK1, RIPK3 and p-MLKL expression in HTR8/SVneo cells, while necrostatin-1 pretreatment reduced RIPK1, RIPK3 and p-MLKL expression in HTR8/SVneo cells under hypoxia. SIRT3 silencing increased RIPK1, RIPK3 and p-MLKL expression and inhibited the invasion, migration, and tube formation of HTR8/SVneo cells under hypoxia. SIRT3 overexpression produced the opposite results. DISCUSSION: We report that SIRT3 deficiency may be involved in the pathogenesis of preeclampsia by increasing necroptosis and causing abnormal trophoblastic biological behavior. The underlying mechanisms need further study.

MicroRNA-133b Inhibits nTumor Cell Proliferation, Migration and Invasion by Targeting SUMO1 in Endometrial Carcinoma.

Objectives: An increasing number of studies have confirmed that microRNAs (miRNAs/miRs), as oncogenes or tumor suppressor genes, play an important regulatory role in the occurrence and development of numerous types of cancer. The aim of the present study was to investigate the potential role and mechanism of miR-133b and small ubiquitin like modifier 1 (SUMO1) in the development of endometrial carcinoma (EC). Methods: First, Venn diagrams are used to identify the differential expressions of miRNAs in EC from GSE35794 and GSE25405 datasets. Next, we conduct a series of functional tests, including Cell Counting Kit-8, wound healing, and transwell and matrigel assays. Then, a bioinformatics tool, is used to identify downstream target genes of miR-133b and to verify the predicted results by RT-qPCR, Western blotting and double luciferase reporter gene analysis. Finally, in order to further study whether the cellular function of miR-133b is mediated by the expression of SUMO1, rescue experiments were carried out. Results: The results of bioinformatics studies showed that the expression of miR-133b was down-regulated in EC tissues, and the expression level of miR-133b was lower in patients with high grade, different histology or menopausal status. The results of functional assay showed that overexpression of miR-133b reduced cell proliferation, migration and invasion. On the contrary, miR-133b silence has the opposite effect. SUMO1 was the direct target of miR-133b and was negatively regulated by miR-133b. The decrease of SUMO1mRNA expression inhibited the proliferation, migration and invasion of EC cells, and reversed the effect of miR-133b on EC cells. Conclusion: The findings from the present study suggested that miR-133b may be a tumor suppressor gene and a potential therapeutic target for the treatment of EC.

Betulinic acid induces apoptosis and impairs migration and invasion in a mouse model of ovarian cancer.

Betulinic acid (BA) was verified to possess plenty of biological activities including anti-tumor, anti-inflammatory and so on. In our research, we studied the growth inhibition, apoptosis promotion and metastasis resistance of ovarian cancer cells by BA. The result showed that BA showed a time- and dose-dependent inhibitory effect on ovarian cancer cell lines. SKOV3 cell line proliferation has a concentration- and time-dependently, which may be inhibited by BA. Furthermore, BA inhibited the metastasis of tumor cells remarkably by inhibiting epithelial-mesenchymal transition process. Beyond that, the weight and volume of subcutaneous tumor was distinctly suppressed by administration of BA in tumor-bearing mice of SKOV3 cells. Pathological and immunohistochemical tests showed that Ki-67+ and MMP-2+ cells were dramatically decreased after BA administration, indicating that BA can not only suppress proliferation, but also inhibit migration of tumor cells. Taken together, BA can be a valuable candidate drug for the treatment of ovarian cancer. PRACTICAL APPLICATIONS: Betulinic acid (BA) isolated from natural plants such as fenugreek, eucalyptus bulb and mulberry has been reported with many biological activities. Results from this study revealed that in vitro and in vivo BA-induced apoptosis and inhibited migration and invasion of human ovarian cancer cells. Therefore, BA from natural plants may be developed as a potential drug for inhibition the development of ovarian cancer cells.