Long non‑coding RNA NR_002794 is upregulated in pre‑eclampsia and regulates the proliferation, apoptosis and invasion of trophoblast cells

PPP2R2A inhibition contributes to preeclampsia by regulating the proliferation, apoptosis, and angiogenesis modulation potential of mesenchymal stem cells

BACKGROUND

The precise mechanisms underlying preeclampsia (PE) pathogenesis remain unclear. Mesenchymal stem cells (MSCs) are involved in the pathology of PE. The aim of our study was to identify the effects of protein phosphatase 2 regulatory subunit B α (PPP2R2A) on MSCs and ascertain its latent role in the progression of PE.

METHODS

Reverse-transcription quantitative polymerase chain reaction and western blot analyses were performed to determine the expression of PPP2R2A in decidual tissue and decidual (d)MSCs from healthy pregnant women and patients with PE as well as the expression levels of Bax and Bcl-2 in dMSCs. The levels of p-PI3K, PI3K, p-AKT, and AKT were determined using western blotting. Cell growth, apoptosis, and migration were analyzed using MTT, flow cytometry, and Transwell assays, respectively. Human umbilical vein endothelial cell (HUVEC) tube formation ability was assayed using a HUVEC capillary-like tube formation assay.

RESULTS

PPP2R2A was downregulated in decidual tissues and dMSCs of patients with PE when compared with that in healthy pregnant women. Moreover, upregulation of PPP2R2A enhanced cell proliferation, reduced apoptotic dMSC, inhibited Bax expression, and increased Bcl-2 levels. Conditioned medium from PPP2R2A-overexpressing dMSCs promoted HTR-8/SVneo cell migration and angiogenesis of HUVEC. Furthermore, the PPP2R2A plasmid suppressed PI3K/AKT pathway activation in dMSCs. However, these effects were partially reversed by LY2940002 treatment.

CONCLUSION

PPP2R2A inhibition contributes to PE by regulating the proliferation, apoptosis, and angiogenesis of MSCs, providing a new therapeutic target for PE diagnosis and treatment.

Immune Dysfunction Mediated by the ceRNA Regulatory Network in Human Placenta Tissue of Intrahepatic Cholestasis Pregnancy

Pregnancy-related intrahepatic cholestasis (ICP) is a serious complication with adverse perinatal outcomes of preterm labor, fetal distress, or stillbirth. As a result, it is important to investigate and identify the potential critical pathogenic mechanisms of ICP. First, we collected the placental tissues from the ICP with placental weight and fetal birth weight loss for the whole transcriptome sequencing. Then we analyzed the differentially expressed (DE) circRNAs (DEcircRNAs) by SRPBM, DElncRNAs by FRKM, DEmiRNAs by TPM, and DEmRNAs by TPM and RSEM. Based on differential expression of term pregnancy placental tissues from pregnancies impacted by ICP (n=7) as compared to gestational aged matched control tissues (n=5), the circ/lncRNA-miRNA-mRNA competitive endogenous RNA (ceRNA) regulatory networks were constructed. The ceRNA regulatory networks covered 3,714 events, including 21 DEmiRNAs, 36 DEcircRNAs, 146 DElncRNAs, and 169 DEmRNAs. According to the functional analysis, ICP complications were linked to the immune system, signal transduction, endocrine system, cell growth and death, and transport and catabolism. Further evidence suggested that the expression of immune-related genes KLRD1, BRAF, and NFATC4 might have a potential ceRNA mechanism by individual lncRNA sponging miR372-3p, miR-371a-3p, miR-7851-3p, and miR-449a to control downstream the level of TNF-α, IFN-γ, and IL-10, thereby regulating the pathophysiology of ICP. Furthermore, our results were validated by the qRT-PCR, western blotting and ELISA assays. In conclusion, this study is the first to evaluate placental ceRNA networks in pregnancies affected by ICP, showing alterations in immune regulatory networks which may impact fetal and placental growth. Overall our these data suggest that the ceRNA regulatory network may refine biomarker predictions for developing novel therapeutic approaches in ICP.

miRNAs in decidual NK cells: regulators worthy of attention during pregnancy

The critical immune effectors, including T, B, and natural killer (NK) cells, dendritic cells, and macrophages participate in regulating immune responses during pregnancy. Among these immune cells, decidual NK (dNK) cells are involved in key placental development processes at the maternal-fetal interface, such as uterine spiral artery remodeling, trophoblast invasion, and decidualization. Mechanistically, dNK cells significantly influence pregnancy outcome by secreting cytokines, chemokines, and angiogenic mediators and by their interactions with trophoblasts and other decidual cells. MicroRNAs (miRNAs) are small non-coding RNA molecules that participate in the initiation and progression of human diseases. Although the functions of circulating miRNAs in pathological mechanism has been extensively studied, the regulatory roles of miRNAs in NK cells, especially in dNK cells, have been rarely reported. In this review, we analyze the effects of miRNA regulations of dNK cell functions on the immune system during gestation. We discuss aberrant expressions of certain miRNAs in dNK cells that may lead to pathological consequences, such as recurrent pregnancy loss (RPL). Interestingly, miRNA expression patterns are also different between dNK cells and peripheral NK (pNK) cells, and pNK cells in the first- and third-trimester of gestation. The dysregulation of miRNA plays a pivotal regulatory role in driving immune functions of dNK and pNK cells. Further understanding of the molecular mechanisms of miRNAs in dNK cells may provide new insights into the development of therapeutics to prevent pregnancy failure.

lncRNA HIF1A-AS2: A potential oncogene in human cancers (Review)

Long non-coding RNAs (lncRNAs) are transcripts that are >200 nucleotides, but with no open reading frame. An increasing number of lncRNAs have been identified following the development of second-generation sequencing technologies, and they have since become a research hotspot. Functionally, they play a vital role in tumor progression, including in tumor proliferation, migration, invasion, apoptosis and acquisition of drug resistance. They regulate gene expression primarily through interaction with DNA, RNA and proteins at the epigenetic, transcriptional and post-transcriptional levels. Endogenous hypoxia-inducible factor 1α antisense RNA 2 (lncRNA HIF1A-AS2) is aberrantly expressed and involved the development/progression of various types of tumors, such as bladder cancer, glioblastoma, breast cancer and osteosarcoma. It plays a vital role in the proliferation, apoptosis, migration, invasion and epithelial-mesenchymal transformation of various tumor cells. This review summarizes the current body of knowledge on the biological functions and related molecular mechanisms of lncRNA HIF1A-AS2 in the development/progression of human tumors and other diseases.

Roles of noncoding RNAs in preeclampsia

Preeclampsia (PE) is an idiopathic disease that occurs during pregnancy. It comprises multiple organ and system damage, and can seriously threaten the safety of the mother and infant throughout the perinatal period. As the pathogenesis of PE is unclear, there are few specific remedies. Currently, the only way to eliminate the clinical symptoms is to terminate the pregnancy. Although noncoding RNA (ncRNA) was once thought to be the "junk" of gene transcription, it is now known to be widely involved in pathological and physiological processes, including pregnancy-related disorders. Moreover, there is growing evidence that the unbalanced expression of specific ncRNA is involved in the pathogenesis of PE. In the present review, we summarize the expression patterns of ncRNAs, i.e., microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), and the functional mechanisms by which they affect the development of PE, and examine the clinical significance of ncRNAs as biomarkers for the diagnosis of PE. We also discuss the contributions made by genetic polymorphisms and epigenetic ncRNA regulation to PE. In the present review, we wish to explore and reinforce the clinical value of ncRNAs as noninvasive biomarkers of PE.

The Role of Long Non-Coding RNAs in Trophoblast Regulation in Preeclampsia and Intrauterine Growth Restriction

Preeclampsia (PE) and Intrauterine Growth Restriction (IUGR) are two pregnancy-specific placental disorders with high maternal, fetal, and neonatal morbidity and mortality rates worldwide. The identification biomarkers involved in the dysregulation of PE and IUGR are fundamental for developing new strategies for early detection and management of these pregnancy pathologies. Several studies have demonstrated the importance of long non-coding RNAs (lncRNAs) as essential regulators of many biological processes in cells and tissues, and the placenta is not an exception. In this review, we summarize the importance of lncRNAs in the regulation of trophoblasts during the development of PE and IUGR, and other placental disorders.

Recent Advances of MicroRNAs, Long Non-coding RNAs, and Circular RNAs in Preeclampsia

Preeclampsia is a clinical syndrome characterized by multiple-organ dysfunction, such as maternal hypertension and proteinuria, after 20 weeks of gestation. It is a common cause of fetal growth restriction, fetal malformation, and maternal death. At present, termination of pregnancy is the only way to prevent the development of the disease. Non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, are involved in important pathological and physiological functions in life cycle activities including ontogeny, reproduction, apoptosis, and cell reprogramming, and are closely associated with human diseases. Accumulating evidence suggests that non-coding RNAs are involved in the pathogenesis of preeclampsia through regulation of various physiological functions. In this review, we discuss the current evidence of the pathogenesis of preeclampsia, introduce the types and biological functions of non-coding RNA, and summarize the roles of non-coding RNA in the pathophysiological development of preeclampsia from the perspectives of oxidative stress, hypoxia, angiogenesis, decidualization, trophoblast invasion and proliferation, immune regulation, and inflammation. Finally, we briefly discuss the potential clinical application and future prospects of non-coding RNA as a biomarker for the diagnosis of preeclampsia.