AGAP2-AS1 promotes the assembly of m6A methyltransferases and activation of the IL6/STAT3 pathway by binding with WTAP in the carcinogenesis of gastric cancer

Owing to the lack of biomarkers for early diagnosis, gastric cancer (GC) is often associated with a poor prognosis. Thus, there is an urgent need to identify early molecular targets in GC. Dysregulated long noncoding RNAs (lncRNAs) have been evaluated by integrated bioinformatics analysis; and we investigate their specific role and potential mechanism via N6-methyladenosine (m6A) methylation modification in the carcinogenesis and progression of GC. In this study, we report upregulation of lncRNA AGAP2-AS1, activated by a gain of H3K4Me3, in GC tissues and cells. AGAP2-AS1 was linked to adverse prognosis in patients with GC. Functionally, AGAP2-AS1 knockdown inhibited cell proliferation and migration of GC cells. Mechanistically, AGAP2-AS1 bound WT1-associated protein (WTAP) to promote the formation of the WTAP/methyltransferase-like 3 (METTL3)/METTL14 m6A methyltransferase complex. AGAP2-AS1 stabilized signal transducer and activator of transcription 3 (STAT3) mRNA in an m6A-dependent manner and, thus, activated the interleukin 6 (IL6)/STAT3 pathway. Importantly, activation of the AGAP2-AS1/WTAP/STAT3 pathways promoted cell proliferation and migration in GC. Collectively, the present findings revealed a novel regulatory relationship between lncRNA and m6A modification. Furthermore, targeting the AGAP2-AS1/WTAP/STAT3 axis may be a promising strategy for the inhibition of inflammation-mediated carcinogenesis and progression in GC.

The regulation of circRNA and lncRNAprotein binding in cardiovascular diseases: Emerging therapeutic targets

Noncoding ribonucleic acids (ncRNAs) are a class of ribonucleic acids (RNAs) that carry cellular information and perform essential functions. This class encompasses various RNAs, such as small nuclear ribonucleic acids (snRNA), small interfering ribonucleic acids (siRNA) and many other kinds of RNA. Of these, circular ribonucleic acids (circRNAs) and long noncoding ribonucleic acids (lncRNAs) are two types of ncRNAs that regulate crucial physiological and pathological processes, including binding, in several organs through interactions with other RNAs or proteins. Recent studies indicate that these RNAs interact with various proteins, including protein 53, nuclear factor-kappa B, vascular endothelial growth factor, and fused in sarcoma/translocated in liposarcoma, to regulate both the histological and electrophysiological aspects of cardiac development as well as cardiovascular pathogenesis, ultimately leading to a variety of genetic heart diseases, coronary heart disease, myocardial infarction, rheumatic heart disease and cardiomyopathies. This paper presents a thorough review of recent studies on circRNA and lncRNAprotein binding within cardiac and vascular cells. It offers insight into the molecular mechanisms involved and emphasizes potential implications for treating cardiovascular diseases.

Mutual Regulation of ncRNAs and Chromatin Remodeling Complexes in Normal and Pathological Conditions

Chromatin remodeling is the one of the main epigenetic mechanisms of gene expression regulation both in normal cells and in pathological conditions. In recent years, a growing number of investigations have confirmed that epigenetic regulators are tightly connected and form a comprehensive network of regulatory pathways and feedback loops. Genes encoding protein subunits of chromatin remodeling complexes are often mutated and change their expression in diseases, as well as non-coding RNAs (ncRNAs). Moreover, different mechanisms of their mutual regulation have already been described. Further understanding of these processes may help apply their clinical potential for establishment of the diagnosis, prognosis, and treatment of the diseases. The therapeutic targeting of the chromatin structure has many limitations because of the complexity of its regulation, with the involvement of a large number of genes, proteins, non-coding transcripts, and other intermediary molecules. However, several successful strategies have been proposed to target subunits of chromatin remodeling complexes and genes encoding them, as well as the ncRNAs that regulate the operation of these complexes and direct them to the target gene regions. In our review, we focus on chromatin remodeling complexes and ncRNAs, their mutual regulation, role in cellular processes and potential clinical application.

The Role of CD4+ T Cells in the Immunotherapy of Brain Disease by Secreting Different Cytokines

Upon different stimulation, naïve CD4⁺ T cells differentiate into various subsets of T helper (Th) cells, including Th1, Th2, Th17, and Tregs. They play both protective and pathogenic roles in the central nervous system (CNS) by secreting different cytokines. Failure of the homeostasis of the subgroups in the CNS can result in different brain diseases. Recently, immunotherapy has drawn more and more attention in the therapy of various brain diseases. Here, we describe the role of different CD4⁺ T cell subsets and their secreted cytokines in various brain diseases, as well as the ways in which by affecting CD4⁺ T cells in therapy of the CNS diseases. Understanding the role of CD4⁺ T cells and their secreted cytokines in the immunotherapy of brain disease will provide new targets and therapeutics for the treatment of brain disease. The role of CD4 + T cell subtypes in different diseases and their associated regulatory genes, proteins, and enzymes. CD4 + T cell subtypes play both protective (green) and pathogenic (red) roles in different brain diseases. The immune regulatory effects of CD4 + T cells and their subtypes are promoted or inhibited by different genes, proteins, and enzymes.

Long non-coding RNA lincRNA-erythroid prosurvival (EPS) alleviates cerebral ischemia/reperfusion injury by maintaining high-temperature requirement protein A1 (Htra1) stability through recruiting heterogeneous nuclear ribonucleoprotein L (HNRNPL)

This study aimed at investigating the role and mechanism of lincRNA-EPS (erythroid prosurvival) in cerebral ischemia/reperfusion (CIR) injury. The results showed that the overexpression of lincRNA-EPS was able to reduce the levels of interleukin-6, tumor necrosis factor-alpha and interleukin-1β stimulated in the OGD-treated Neuro-2a (N-2a) cells. The levels of reactive oxygen species and malondialdehyde were enhanced while the superoxide dismutase levels were reduced by oxygen and glucose deprivation (OGD) treatment, in which the lincRNA-EPS overexpression could reverse this effect in the cells. LincRNA-EPS interacted with high-temperature requirement protein A1 (Htra1) and heterogeneous nuclear ribonucleoprotein L (HNRNPL), and their depletion inhibited the Htra1 mRNA stability in N-2a cells. HNRNPL knockdown blocked lincRNA-EPS overexpression-induced Htra1 expression in the cells. The depletion of Htra1 could rescue lincRNA-EPS overexpression-mediated N-2a cell injury, inflammation, and oxidative stress induced by OGD. Functionally, lincRNA-EPS alleviates CIR injury of the middle cerebral artery occlusion/reperfusion mice in vivo. In conclusion, lincRNA-EPS attenuates CIR injury by maintaining Htra1 stability through recruiting HNRNPL.

LncRNA KCNQ1OT1 depletion inhibits the malignant development of atherosclerosis by miR-145-5p

BACKGROUND

Atherosclerosis (AS) is a lipid-driven inflammatory disease of the arterial intima. Evidence is growing that dysregulation of lncRNAs is implicated in the pathogenesis of AS. In this research, the role of lncRNA KCNQ1OT1 in AS was investigated.

METHODS

ApoE-/- mice were fed on a high fat diet to establish mouse models of AS. Macrophages (THP-1) were treated with oxidized low-density lipoprotein (ox-LDL) to establish cell models of AS. Atherosclerotic lesions of AS mice were determined by performing Oil red O staining. Lipid metabolic disorders and inflammatory were detected using specific assay kits. KCNQ1OT1 and miR-145-5p expression was measured using RT-qPCR. Levels of PPARα and CPT1 were measured using western blot.

RESULTS

KCNQ1OT1 expression was upregulated and miR-145-5p was downregulated in atherosclerotic plaques of AS mice and ox-LDL-treated THP-1 cells. Lipid metabolic disorders and inflammation in vivo and in vitro were attenuated by either KCNQ1OT1 knockdown or miR-145-5p overexpression. Additionally, KCNQ1OT1 acted as a molecular sponge of miR-145-5p and downregulated miR-145-5p expression. Furthermore, silencing miR-145-5p abolished the effect of KCNQ1OT1 knockdown.

CONCLUSION

Silencing KCNQ1OT1 attenuates AS progression by sponging miR-145-5p.

Roles and functions of antisense lncRNA in vascular aging

Vascular aging is a major cause of morbidity and mortality in the elderly population. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), forming the intima and media layers of the vessel wall respectively, are closely associated with the process of vascular aging and vascular aging-related diseases. Numerous studies have revealed the pathophysiologic mechanism through which lncRNA contributes to vascular aging, hence more attention is now paid to the role played by antisense long non-coding RNA (AS-lncRNA) in the pathogenesis of vascular aging. Nonetheless, only a small number of studies focus on the specific mechanism through which AS-lncRNA mediates vascular aging. In this review, we summarize the roles and functions of AS-lncRNA with regards to the development of vascular aging and vascular aging-related disease. We also aim to deepen our understanding of this process and provide alternative therapeutic modalities for vascular aging-related diseases.

Coming to the Rescue: Regulatory T Cells for Promoting Recovery After Ischemic Stroke

Immune cell infiltration to the injured brain is a key component of the neuroinflammatory response after ischemic stroke. In contrast to the large amount of proinflammatory immune cells, regulatory T cells, are an important subgroup of T cells that are involved in maintaining immune homeostasis and suppress an overshooting immune reaction after stroke. Numerous previous reports have consistently demonstrated the beneficial role of this immunosuppressive immune cell population during the acute phase after experimental stroke by limiting inflammatory lesion progression. Two recent studies expanded now this concept and demonstrate that regulatory T cells-mediated effects also promote chronic recovery after stroke by promoting a proregenerative tissue environment. These recent findings suggest that boosting regulatory T cells could be beneficial beyond modulating the immediate neuroinflammatory response and improve chronic functional recovery.

CDKN2B-AS1 Aggravates the Pathogenesis of Human Thoracic Aortic Dissection by Sponge to miR-320d

In the present study, the role and molecular mechanism of long noncoding RNA CDKN2B-AS1 in human thoracic aortic dissection (TAD), a highly lethal cardiovascular disease, was investigated. The expression of CDKN2B-AS1 in human TAD and normal aortic tissues of donors were examined by quantitative real-time polymerase chain reaction. RNA pull-down assay and a series of luciferase reporter assays were performed to predict the relationships between CDKN2B-AS1, miR-320d, and STAT3. Cell counting kit 8 (CCK-8), TUNEL, and western blot assays were applied to validate the biological functions of CDKN2B-AS1 in rat aortic vascular smooth muscle cells. Results showed that CDKN2B-AS1 was expressed at a higher level in human TAD than in normal aortic tissues. CDKN2B-AS1 overexpression significantly promoted apoptosis and suppressed the proliferation of vascular smooth muscle cells. CDKN2B-AS1 silence exhibited the opposite effects. Mechanistically, CDKN2B-AS1 was identified as a molecular sponge for miR-320d and positively modulated STAT3 expression via repressing miR-320d. In conclusion, our study revealed that CDKN2B-AS1 was dysregulated and displayed multiple potential functions in human TAD. These findings suggested that CDKN2B-AS1 was a novel potential therapeutic target for human TAD.

NCK1-AS1 promotes the progression of lung squamous cell carcinoma through transcriptionally upregulating NCK1 via interacting with MYC

Lung squamous cell carcinoma (LUSC) is a prevalent subtype of nonsmall cell lung cancer (NSCLC). Dysregulated long noncoding RNAs (lncRNAs) are increasingly identified as pivotal modulators in cancer progression. NCK1 divergent transcript (NCK1-AS1) is a lncRNA that has been proven to be oncogenic in different types of human cancers. However, whether it exerts similar functions in LUSC remains to be elusive. The present study focused on investigating the influence of NCK1-AS1 on the cellular process in LUSC and exploring its underlying mechanism. Through online bioinformatics analysis, we obtained a high NCK1-AS1 level in LUSC tissues. Meanwhile, we confirmed that NCK1-AS1 was upregulated in LUSC cells. Gain- or loss-of-function assays suggested that NCK1-AS1 prompted cell proliferation and migration, whilst impeded cell apoptosis in LUSC. Mechanistically, we revealed that NCK1-AS1 induced the upregulation of its nearby gene NCK adaptor protein 1 (NCK1) at the transcriptional level by interacting with the transcription factor MYC proto-oncogene (MYC). Rescue assays indicated that NCK1 participated in the regulation of NCK1-AS1 on LUSC progression. In conclusion, we firstly demonstrated the oncogenic role of NCK1-AS1 in LUSC and illustrated its downstream molecular mechanism.

The Regulatory Functions of lncRNAs on Angiogenesis Following Ischemic Stroke

Ischemic stroke is one of the leading causes of global mortality and disability. It is a multi-factorial disease involving multiple factors, and gene dysregulation is considered as the major molecular mechanisms underlying disease progression. Angiogenesis can promote collateral circulation, which helps the restoration of blood supply in the ischemic area and reduces ischemic necrosis following ischemic injury. Aberrant expression of long non-coding RNAs (lncRNAs) in ischemic stroke is associated with various biological functions of endothelial cells and serves essential roles on the angiogenesis of ischemic stroke. The key roles of lncRNAs on angiogenesis suggest their potential as novel therapeutic targets for future diagnosis and treatment. This review elucidates the detailed regulatory functions of lncRNAs on angiogenesis following ischemic stroke through numerous mechanisms, such as interaction with target microRNAs, downstream signaling pathways and target molecules.

Long non-coding RNAs: the tentacles of chromatin remodeler complexes

Chromatin remodeler complexes regulate gene transcription, DNA replication and DNA repair by changing both nucleosome position and post-translational modifications. The chromatin remodeler complexes are categorized into four families: the SWI/SNF, INO80/SWR1, ISWI and CHD family. In this review, we describe the subunits of these chromatin remodeler complexes, in particular, the recently identified members of the ISWI family and novelties of the CHD family. Long non-coding (lnc) RNAs regulate gene expression through different epigenetic mechanisms, including interaction with chromatin remodelers. For example, interaction of lncBRM with BRM inhibits the SWI/SNF complex associated with a differentiated phenotype and favors assembly of a stem cell-related SWI/SNF complex. Today, over 50 lncRNAs have been shown to affect chromatin remodeler complexes and we here discuss the mechanisms involved.

RETRACTED: Long noncoding RNA LINC00671 exacerbates osteoarthritis by promoting ONECUT2-mediated Smurf2 expression and extracellular matrix degradation

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Authors and Editor-in-Chief. The corresponding author contacted the journal and stated: “…we have obtained different results from this paper (onecut2 targeted regulation of Smurf2 / GSK-3 β part), and repeated experiments cannot fully verify this result”. The authors requested retraction of the article. Concern was also raised about the integrity of an image in Figure 1H, which appears to also be found in another publication, as detailed here: https://pubpeer.com/publications/FBECF0BCB952DCC563AA5C4D760B32 and here: https://docs.google.com/spreadsheets/d/1r0MyIYpagBc58BRF9c3luWNlCX8VUvUuPyYYXzxWvgY/edit#gid=262337249. The journal requested the corresponding author comment on these concerns and provide the raw data. The authors were unable to satisfactorily fulfill this request. The Editor-in-Chief assessed the case and decided to retract the article.

Long non-coding RNA CDKN2B-AS1 regulates high glucose-induced human mesangial cell injury via regulating the miR-15b-5p/WNT2B axis

BACKGROUND

Long non-coding RNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) has been reported to be related to diabetic nephropathy (DN) progression. However, the regulatory mechanisms of CDKN2B-AS1 in DN are unclear.

METHODS

High glucose (HG) was used to induce human mesangial cells (HMCs) for establishing the DN model. Expression levels of CDKN2B-AS1, microRNA (miR)-15b-5p, wingless-Type family member 2B (WNT2B) mRNA in serum and HMCs were detected through quantitative real-time polymerase chain reaction (qRT-PCR). The viability and cell cycle progression of HMCs were determined with Cell Counting Kit-8 (CCK-8) or flow cytometry assays. The levels of several proteins and inflammatory factors in HMCs were analyzed by western blotting or enzyme-linked immunosorbent assay (ELISA). The relationship between CDKN2B-AS1 or WNT2B and miR-15b-5p was verified with dual-luciferase reporter assay.

RESULTS

CDKN2B-AS1 and WNT2B were upregulated while miR-15b-5p was downregulated in serum of DN patients and HG-treated HMCs. CDKN2B-AS1 inhibition reduced HG-induced viability, cell cycle progression, ECM accumulation, and inflammation response in HMCs. CDKN2B-AS1 regulated WNT2B expression via competitively binding to miR-15b-5p. MiR-15b-5p inhibitor reversed CDKN2B-AS1 knockdown-mediated influence on viability, cell cycle progression, ECM accumulation, and inflammation response of HG-treated HMCs. The repressive effect of miR-15b-5p mimic on viability, cell cycle progression, ECM accumulation, and inflammation response of HG-treated HMCs was abolished by WNT2B overexpression.

CONCLUSION

CDKN2B-AS1 regulated HG-induced HMC viability, cell cycle progression, ECM accumulation, and inflammation response via regulating the miR-15b-5p/WNT2B axis, provided a new mechanism for understanding the development of DN.

Long noncoding RNA Nespas inhibits apoptosis of epileptiform hippocampal neurons by inhibiting the PI3K/Akt/mTOR pathway

Epilepsy is one of the most common neurological diseases with spontaneous recurrent seizures. Long noncoding RNAs (lncRNAs) are crucial modulators in numerous diseases, including epilepsy. However, the functional role and potential mechanism of lncRNA Nespas in epilepsy remain unknown. Our study clarified that Nespas was underexpressed in epileptiform hippocampal tissues and neurons. Furthermore, Nespas promoted hippocampal neuron viability and proliferation, and inhibited hippocampal neuron apoptosis. Mechanistically, Nespas interacted with microRNA 615-3p (miR-615-3p) in epileptiform hippocampal neurons. 26S proteasome non-ATPase regulatory subunit 11 (Psmd11) was a downstream target of miR-615-3p, and Nespas elevated Psmd11 expression via competitively binding to miR-615-3p in epileptiform hippocampal neurons. In addition, rescue assays suggested that Nespas promoted hippocampal neuron viability and proliferation, and suppressed hippocampal neuron apoptosis by upregulation of Psmd11. Furthermore, Nespas suppressed the PI3K/Akt/mTOR pathway via upregulating Psmd11 in epileptiform hippocampal neurons. This report explored the function and regulatory mechanism of Nespas in epileptiform hippocampal neurons for the first time. Our findings revealed that Nespas suppressed the apoptosis of epileptiform hippocampal neurons by inhibiting the PI3K/Akt/mTOR pathway via upregulation of Psmd11 at a miR-615-3p dependent way, indicating that Nespas may offer a new direction for the treatment of epilepsy.

LncRNA LL22NC03-N14H11.1 promoted hepatocellular carcinoma progression through activating MAPK pathway to induce mitochondrial fission

Involvement of long non-coding RNAs (lncRNAs) in hepatocarcinogenesis has been largely documented. Mitochondrial dynamics is identified to impact survival and metastasis in tumors including hepatocellular carcinoma (HCC), but the underlying mechanism remains poorly understood. This study planned to explore the regulation of lncRNA LL22NC03-N14H11.1 on HCC progression and mitochondrial fission. Dysregulated lncRNAs in HCC are identified through circlncRNAnet and GEPIA bioinformatics tools. Biological function of LL22NC03-N14H11.1 in HCC was detected by CCK-8 assay, flow cytometry analysis, transwell invasion, and wound healing assays. Molecular interactions were determined by RNA immunoprecipitation, RNA pull-down, and co-immunoprecipitation assays. Results showed that LL22NC03-N14H11.1 was upregulated in HCC tissues and cells. Functionally, LL22NC03-N14H11.1 contributed to cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) in HCC. Moreover, LL22NC03-N14H11.1 facilitated mitochondrial fission in HCC cells. Mechanistically, LL22NC03-N14H11.1 recruited Myb proto-oncogene (c-Myb) to repress the transcription of leucine zipper-like transcription regulator 1 (LZTR1), so as to inhibit LZTR1-mediated ubiquitination of H-RAS (G12V), leading to the activation of mitogen-activated protein kinase (MAPK) signaling and induction of p-DRP1 (Serine 616). In conclusion, this study firstly revealed that lncRNA LL22NC03-N14H11.1 promoted HCC progression through activating H-RAS/MAPK pathway to induce mitochondrial fission, indicating LL22NC03-N14H11.1 as a novel potential biomarker for HCC treatment.

Exosomal lncRNA DOCK9-AS2 derived from cancer stem cell-like cells activated Wnt/β-catenin pathway to aggravate stemness, proliferation, migration, and invasion in papillary thyroid carcinoma

Exosomal long non-coding RNAs (lncRNAs) are crucial factors that mediate the extracellular communication in tumor microenvironment. DOCK9 antisense RNA2 (DOCK9-AS2) is an exosomal lncRNA which has not been investigated in papillary thyroid carcinoma (PTC). Based on the result of differentially expressed lncRNAs in PTC via bioinformatics databases, we discovered that DOCK9-AS2 was upregulated in PTC, and presented elevation in plasma exosomes of PTC patients. Functionally, DOCK9-AS2 knockdown reduced proliferation, migration, invasion, epithelial-to-mesenchymal (EMT) and stemness in PTC cells. PTC-CSCs transmitted exosomal DOCK9-AS2 to improve stemness of PTC cells. Mechanistically, DOCK9-AS2 interacted with SP1 to induce catenin beta 1 (CTNNB1) transcription and sponged microRNA-1972 (miR-1972) to upregulate CTNNB1, thereby activating Wnt/β-catenin pathway in PTC cells. In conclusion, PTC-CSCs-derived exosomal lncRNA DOCK9-AS2 activated Wnt/β-catenin pathway to aggravate PTC progression, indicating that DOCK9-AS2 was a potential target for therapies in PTC.

HOXB-AS1 accelerates the tumorigenesis of glioblastoma via modulation of HOBX2 and HOBX3 at transcriptional and posttranscriptional levels

Glioblastoma (GBM) is the most universal and invasive brain tumor among adults. Increasing studies have reported that long noncoding RNAs play vital roles in regulating downstream molecules at the transcriptional or posttranscriptional level in tumor progression. The purpose of the current research was to inquire the modulation mechanism by which homeobox B cluster antisense RNA 1 (HOXB-AS1) functioned in GBM. Our study first discovered the lifted expression of HOXB-AS1 and its nearby genes HOXB2 and HOXB3 in GBM and the positive relationship between HOXB-AS1 and HOXB2 or HOXB3. Loss-of-function assays and in vivo study detected that silencing of HOXB-AS1, HOXB2, or HOXB3 restrained the proliferation and induced the apoptosis in GBM. In addition, mechanism experiments demonstrated that HOXB-AS1 recruited interleukin enhancer-binding factor 3 (ILF3) to regulate HOXB2 and HOXB3 expression at the transcriptional level, and HOXB-AS1 sponged miR-186-5p to modulate HOXB2 and HOXB3 expression at posttranscriptional level. Finally, the regulatory mechanism of HOXB-AS1 in GBM was certified through rescue experiments. Our results indicated that HOXB-AS1 boost the HOXB2 or HOXB3 expression at the transcriptional and posttranscriptional levels. We detected the HOXB-AS1-ILF3-HOXB2/HOXB3 axis and HOXB-AS1-miR-186-5p-HOXB2/HOXB3 axis driving the GBM progression, which might generate more effective diagnostic biomarkers and therapeutic targets for patients with GBM.

LncRNA MEG3-210 regulates endometrial stromal cells migration, invasion and apoptosis through p38 MAPK and PKA/SERCA2 signalling via interaction with Galectin-1 in endometriosis

BACKGROUND

Endometriosis is a benign gynaecological disease with malignant characteristics that severely affects women's quality of life. Long noncoding RNA maternally expressed gene 3 (LncRNA MEG3) is a tumour suppressor that is downregulated in various cancer cells and tissues, and regulates multiple biological processes. Emerging studies have revealed that the interactions between MEG3 and proteins are involved in disease progression. Galectin-1 affects cell motility, signal transduction and vascularization, and is overexpressed in endometriosis. Our study is the first to explore the role of MEG3-210 transcript in endometriosis and to reveal the regulatory mechanism mediated by the interaction between MEG3-210 and Galectin-1.

MATERIALS AND METHODS

Endometrial tissues and sera from patients with endometriosis and controls were collected. qRT-PCR was performed to detect the expression of MEG3-210 in the endometrium and endometrial stromal cells (ESCs). The CCK-8 assay, the Transwell assay, flow cytometry and animal models were conducted to evaluate the functions of MEG3-210 in vitro and in vivo. Bioinformatic analysis, Western blot assays, RNA-pull down assays and RNA immunoprecipitation were used to explore the potential mechanism of MEG3-210 in endometriosis.

RESULTS

Our results showed that MEG3-210 expression was lower in the eutopic endometrium of women with endometriosis. MEG3-210 downregulation promoted ESCs migration, invasion, anti-apoptosis in vitro and growth of endometriotic lesions in vivo. Furthermore, MEG3-210 downregulation could activate p38 mitogen-activated protein kinase (p38 MAPK) and inhibit cAMP-dependent protein kinase A/sarcoplasmic reticulum Ca²⁺ ATPase 2 (PKA/SERCA2) signalling, which was mediated by Galectin-1. The protein levels of Galectin-1 in patients with endometriosis were elevated, and Galectin-1 siRNA could reduce the size of lesions.

CONCLUSION

MEG3-210 regulates ESCs through p38 MAPK and PKA/SERCA signalling via interaction with Galectin-1. The novel regulatory mechanism may provide new insights into drug therapy and the diagnosis of endometriosis.

SPAG5-AS1 inhibited autophagy and aggravated apoptosis of podocytes via SPAG5/AKT/mTOR pathway

Objectives

Podocyte injury is a prediction marker of diabetic nephropathy (DN), and AKT/mTOR pathway–mediated inhibition of autophagy is widely reported to contribute to podocyte damage. Recent study stated that sperm‐associated antigen 5 (SPAG5) activated AKT/mTOR signalling in bladder urothelial carcinoma, indicating SPAG5 might regulate autophagy and play a role in podocyte damage.

Materials and methods

Apoptosis and autophagy of human podocytes (HPCs) were detected by flow cytometry and immunofluorescence (IF). Gene level was assessed by Western blot and RT‐qPCR. Molecular interactions were determined by pulldown, RNA immunoprecipitation (RIP), co‐immunoprecipitation (co‐IP), chromatin immunoprecipitation (ChIP) and luciferase reporter assays.

Results

SPAG5 mRNA and protein levels were upregulated under high glucose treatment in HPCs. Silencing SPAG5 reversed the increase of apoptosis and decrease of autophagy in high glucose–treated HPCs. Later, we found a long non‐coding RNA (lncRNA) SPAG5 antisense RNA1 (SPAG5‐AS1) as a neighbour gene to SPAG5. Mechanistically, YY1 transcriptionally upregulated SPAG5‐AS1 and SPAG5 in high glucose–treated podocytes. SPAG5‐AS1 acted as a competitive endogenous RNA (ceRNA) to regulate miR‐769‐5p/YY1 axis and induce SPAG5. SPAG5‐AS1 interacted with ubiquitin‐specific peptidase 14 (USP14) and leads to de‐ubiquitination and stabilization of SPAG5 protein.

Conclusions

This study revealed that SPAG5‐AS1 inhibited autophagy and aggravated apoptosis of podocytes via SPAG5/AKT/mTOR pathway, indicating SPAG5‐AS1/SPAG5 as a potential target for the alleviation of podocyte injury and offering new thoughts for the treatments of DN.