A novel circRNA-miRNA-mRNA network identifies circ-YOD1 as a biomarker for coronary artery disease

Circ_0036490 and DKK1 competitively bind miR-29a to promote lipopolysaccharides-induced human gingival fibroblasts injury

MicroRNA (miRNA) plays a regulatory role in periodontitis. This study aimed to explore whether miR-29a could affect lipopolysaccharides (LPSs)-induced injury in human gingival fibroblasts (HGFs) through the competitive endogenous RNAs (ceRNA) mechanism. Periodontal ligament (PDL) tissues and HGFs were derived from patients with periodontitis and healthy volunteers. Periodontitis cell model was established by treating HGFs with LPS. Expression levels of circ_0036490, miR-29a, and DKK1 were evaluated by the reverse transcription quantitative real-time PCR (RT-qPCR) method. Western blotting assay was performed to assess protein expression levels of pyroptosis-related proteins and Wnt signalling related proteins. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. Concentration of lactate dehydrogenase (LDH), interleukin (IL)-1β, and IL-18 were determined by Enzyme-linked immunosorbent assay (ELISA). Pyroptosis rate were determined by flow cytometry assay to evaluate pyroptosis. The interaction between miR-29a and circ_0036490 or DKK1 was verified by dual-luciferase reporter and RNA pull-down assays. MiR-29a expression was lower in PDL tissues of patients with periodontitis than that in healthy group; likewise, miR-29a was also downregulated in LPS-treated HGFs. Overexpression of miR-29a increased cell viability and decreased pyroptosis of HGFs induced by LPS while inhibition of miR-29a exerted the opposite role. MiR-29a binds to circ_0036490 and elevation of circ_0036490 contributed to dysfuntion of LPS-treated HGFs and reversed the protection function of elevated miR-29a. In addition, miR-29a targets DKK1. Overexpression of DKK1 abrogated the effects of overexpressed miR-29a on cell vaibility, pyroptosis, and protein levels of Wnt signalling pathway of LPS-treated HGFs. Circ_0036490 and DKK1 competitively bind miR-29a to promote LPS-induced HGF injury in vitro. Wnt pathway inactivated by LPS was activated by miR-29a. Thence, miR-29a may be a promising target for periodontitis.

Hsa_circRNA_0000284 acts as a ceRNA to participate in coronary heart disease progression by sponging miRNA-338-3p via regulating the expression of ETS1

Coronary heart disease (CHD) is a prevalent global cause of death. Research suggests that circular RNAs (circRNAs) play a role in the development of CHD. In this study, we investigated the expression of hsa_circRNA_0000284 in peripheral blood leukocytes (PBLs) obtained from a cohort of 94 CHD patients aged over 50 years, as well as 126 age-matched healthy controls (HC). An in vitro inflammatory and oxidative injury cell model that simulates CHD was used to evaluate changes in hsa_ circRNA _0000284 under stress. CRISPR/Cas9 technology was used to evaluate changes in hsa_circRNA_0000284 expression. An hsa_ circRNA_0000284 overexpression and silencing cell model was used to analyze the biological functions of hsa_circRNA_0000284. Bioinformatics, qRT-PCR, viral transfection technology, and luciferase assays were used to evaluate the potential hsa_circRNA_0000284/miRNA-338-3p/ETS1 axis. Western blotting analysis was performed to detect protein expression. Herein, PBLs from CHD patients exhibited downregulation of hsa_circRNA_0000284 expression. Exposure to oxidative stress and inflammation can induce damage to human umbilical endothelial cells, resulting in the downregulation of hsa_circRNA_0000284 expression. The expression of hsa_circRNA_0000284 in EA-hy926 cells was significantly reduced after the AluSq2 element of hsa_circRNA_0000284 had been knocked out. The expression of hsa_circRNA_0000284 affected proliferation, cycle distribution, aging, and apoptosis in EA-hy926 cells. Consistent with the results of cell transfection experiments and luciferase assays, Western blotting showed that hsa_circRNA_0000284 plays a role in the regulation of hsa-miRNA-338-3p expression. Subsequently, hsa-miRNA-338-3p was found to be involved in the regulation of ETS1 expression.Communicated by Ramaswamy H. Sarma.

Identification and verification of circRNA biomarkers for coronary artery disease based on WGCNA and the LASSO algorithm

BACKGROUND

The role of circular RNAs (circRNAs) as biomarkers of coronary artery disease (CAD) remains poorly explored. This study aimed to identify and validate potential circulating circRNAs as biomarkers for the diagnosis of CAD.

METHODS

The expression profile of circRNAs associated with CAD was obtained from Gene Expression Omnibus (GEO) database. Differential expression analysis, weighted gene co-expression network analysis (WGCNA) and least absolute shrinkage and selection operation (LASSO) were employed to identify CAD-related hub circRNAs. The expression levels of these hub circRNAs were validated using qRT-PCR in blood samples from 100 CAD patients and 100 controls. The diagnostic performance of these circRNAs was evaluated through logistic regression analysis, receiver operator characteristic (ROC) analysis, integrated discrimination improvement (IDI), and net reclassification improvement (NRI). Functional enrichment analyses were performed to predict the possible mechanisms of circRNAs in CAD.

RESULTS

A total of ten CAD-related hub circRNAs were identified through WGCNA and LASSO analysis. Among them, hsa_circ_0069972 and hsa_circ_0021509 were highly expressed in blood samples of CAD patients, and they were identified as independent predictors after adjustment for relevant confounders. The area under the ROC curve for hsa_circ_0069972 and hsa_circ_0021509 was 0.760 and 0.717, respectively. The classification of patients was improved with the incorporation of circRNAs into the clinical model composed of conventional cardiovascular risk factors, showing an IDI of 0.131 and NRI of 0.170 for hsa_circ_0069972, and an IDI of 0.111 and NRI of 0.150 for hsa_circ_0021509. Functional enrichment analyses revealed that the hsa_circ_0069972-miRNA-mRNA network was enriched in TGF-β、FoxO and Hippo signaling pathways, while the hsa_circ_0021509-miRNA-mRNA network was enriched in PI3K/Akt and MAPK signaling pathways.

CONCLUSION

Hsa_circ_0069972 and hsa_circ_0021509 were identified by integrated analysis, and they are highly expressed in CAD patients. They may serve as novel biomarkers for CAD.

Non-Coding Ribonucleic Acids as Diagnostic and Therapeutic Targets in Cardiac Fibrosis

PURPOSE OF REVIEW

Cardiac fibrosis is a crucial juncture following cardiac injury and a precursor for many clinical heart disease manifestations. Epigenetic modulators, particularly non-coding RNAs (ncRNAs), are gaining prominence as diagnostic and therapeutic tools.

RECENT FINDINGS

miRNAs are short linear RNA molecules involved in post-transcriptional regulation; lncRNAs and circRNAs are RNA sequences greater than 200 nucleotides that also play roles in regulating gene expression through a variety of mechanisms including miRNA sponging, direct interaction with mRNA, providing protein scaffolding, and encoding their own products. NcRNAs have the capacity to regulate one another and form sophisticated regulatory networks. The individual roles and disease relevance of miRNAs, lncRNAs, and circRNAs to cardiac fibrosis have been increasingly well described, though the complexity of their interrelationships, regulatory dynamics, and context-specific roles needs further elucidation. This review provides an overview of select ncRNAs relevant in cardiac fibrosis as a surrogate for many cardiac disease states with a focus on crosstalk and regulatory networks, variable actions among different disease states, and the clinical implications thereof. Further, the clinical feasibility of diagnostic and therapeutic applications as well as the strategies underway to advance ncRNA theranostics is explored.

CircZNF609 sponges miR-135b to up-regulate SEMA3A expression to alleviate ox-LDL-induced atherosclerosis

The initiation and progression of atherosclerotic plaque caused by abnormal lipid metabolism is one of the main causes of atherosclerosis (AS). Lipid droplet accumulation has become a novel research pointcut for AS treatment in recent years. In AS patients, miR-135b level was up-regulated relative to the normal cases, which showed negative correlations with the levels of Semaphorin 3A (SEMA3A) and circZNF609, separately. The U937-derived macrophages were cultured with ox-LDL to establish AS models in vitro. After that, the lipid accumulation, inflammation, mitochondrial dysfunction and cell death were evaluated by ORO, ELISA, RT-qPCR, western blot, JC-1 and FCM assays respectively. Transfection of the circZNF609 expression vector notably declined lipid accumulation, attenuated inflammation, reduced mitochondrial dysfunction and inhibited cell death in ox-LDL-stimulated cells. The direct binding of miR-135b to circZNF609 in vitro was confirmed using RIP assay, and SEMA3A expression was up-regulated by circZNF609 overexpression. After manipulating the endogenous expressions of circZNF609, miR-135b and SEMA3A, the above damages in ox-LDL-stimulated cells were rescued by inhibition of miR-135b expression and overexpression of circZNF609 or SEMA3A. Besides, the AS mice model was built to demonstrate the excessive lipid accumulation, increasing inflammation and cell death in AS pathogenesis according to the results of HE staining, ELISA and IHC assays, while these damages were reversed after overexpression of circZNF609 or SEMA3A. In AS models, overexpressed circZNF609 prevents the AS progression through depleting miR-135b expression and subsequent up-regulation of SEMA3A expression to overwhelm lipid accumulation, mitochondrial dysfunction and cell death.

Protosappanin B enhances the chemosensitivity of 5-fluorouracil in colon adenocarcinoma by regulating the LINC00612/microRNA-590-3p/Golgi phosphoprotein 3 axis

BACKGROUND

5-fluorouracil (5-FU) is conventionally used in chemotherapy for colon adenocarcinomas. Acquired resistance of 5-FU remains a clinical challenge in colon cancer, and efforts to develop targeted agents to reduce resistance have not yielded success. Protosappanin B (PSB), the main component of Lignum Sappan extract, is known to exhibit anti-tumor effects. However, whether and how PSB could improve 5-FU resistance in colon cancer have not yet been established. In this study, we aimed to explore the effects and underlying mechanisms of PSB in 5-FU-induced chemoresistance in colon adenocarcinoma.

METHODS

Forty-seven paired colon cancer tissue samples from patients who received 5-FU chemotherapy were collected as clinical samples. Two 5-FU resistant colon cancer cell lines were established for in vitro experiments. Reverse transcription-quantitative PCR (RT-qPCR) was performed to determine the mRNA and microRNA (miRNA) expression levels in colon adenocarcinoma tissues and cell lines. Cell Counting Kit-8 (CCK-8) and flow cytometry assays were performed to evaluate cell proliferation and apoptosis, respectively.

RESULTS

LINC00612 was highly expressed in colon adenocarcinoma samples and 5-FU resistant colon cancer cells. LINC00612 knockdown enhances 5-FU chemosensitivity in 5-FU resistant cells. Notably, PSB treatment attenuated LINC00612 expression in 5-FU resistant colon adenocarcinoma cells. Moreover, PSB treatment reversed the increase in LINC00612-induced 5-FU resistance. Mechanistically, LINC00612 specifically bound to miR-590-3p, which promoted 5-FU resistance in colon adenocarcinoma cells and attenuated the inhibitory effect of LINC00612 on GOLPH3 expression.

CONCLUSION

PSB attenuates 5-FU chemoresistance in colon adenocarcinoma by regulating the LINC00612/miRNA-590-3p/GOLPH3 axis.

Downregulation of circ_0035292 Alleviates LPS-Induced WI-38 Cell Injury via Targeting miR-494-3p/TLR4 Pathway in Infantile Pneumonia

Circular RNAs (circRNAs) have been confirmed to mediate infantile pneumonia development. In this, we investigated the role and new mechanism of circ_0035292 regulating infantile pneumonia progression. Lipopolysaccharide (LPS)-treated WI-38 cells were used to mimic infantile pneumonia cell injury models. Quantitative real-time PCR was used to measure circ_0035292, microRNA (miR)-494-3p and toll-like receptor 4 (TLR4). Cell proliferation and apoptosis were assessed by MTT assay, EdU assay, and flow cytometry. Protein expression was tested using western blot analysis. Inflammation and oxidative stress were evaluated by measuring IL-6, IL-1β, MDA and SOD levels using ELISA assay and corresponding kits. RNA interaction was confirmed by dual-luciferase reporter assay and RIP assay. Circ_0035292 had elevated expression in infantile pneumonia patients and LPS-induced WI-38 cells. Silenced circ_0035292 could enhance WI-38 cell proliferation, while suppress apoptosis, inflammation and oxidative stress under LPS treatment. Mechanically, circ_0035292 targeted miR-494-3p to positively regulate TLR4. The rescue experiments indicated that miR-494-3p inhibitor abolished the function of circ_0035292 knockdown, and TLR4 overexpression reversed the inhibitory effect of miR-494-3p on LPS-induced WI-38 cell injury. Circ_0035292 might be a potential target for infantile pneumonia treatment, which knockdown could relieve LPS-induced cell injury via the regulation of miR-494-3p/TLR4 axis.

Downregulation of circAsxl2 Relieves Neuronal Injury Induced by oxygen-glucose deprivation/reperfusion

BACKGROUND

Circular RNAs (circRNAs) have been shown to play an important role in cerebral ischemia-reperfusion (I/R) injury. However, the role of circAsxl2 (mmu_circ_0000346) in cerebral I/R injury remains unclear.

METHODS

Mouse brain neuronal cell line (HT-22) was used to perform oxygen-glucose deprivation/reperfusion (OGD/R) treatment. The levels of circAsxl2, microRNA (miR)-130b-5p and forkhead box O3 (FOXO3) were determined using quantitative real-time PCR. Cell viability and apoptosis were measured using cell counting kit 8 assay and flow cytometry. Commercial kits were used to assess cell cytotoxicity, inflammation and oxidative stress. Protein expression was analyzed by western blot. RNA interaction was verified using dual-luciferase reporter assay, RIP assay and RNA pull-down assay.

RESULTS

CircAsxl2 was highly expressed in OGD/R-induced HT-22 cells, and its silencing could alleviate OGD/R-induced apoptosis, inflammation and oxidative stress in HT-22 cells. MiR-130b-5p was sponged by circAsxl2, and its inhibitor could overturn the regulation of circAsxl2 knockdown on OGD/R-induced neuronal injury. FOXO3 was targeted by miR-130b-5p and its expression was positively regulated by circAsxl2. In addition, the regulation of circAsxl2 knockdown on OGD/R-induced neuronal injury also was reversed by FOXO3 overexpression.

CONCLUSION

CircAsxl2/miR-130b-5p/FOXO3 axis accelerated OGD/R-induced neuronal injury, which might provide effective strategies for treating cerebral I/R injury.

Identification of immune-related genes and integrated analysis of immune-cell infiltration in melanoma

OBJECTIVE

This study was conducted to screen out immune-related genes in connection with the prognosis of melanoma, construct a prognosis model and explore the relevant mechanisms.

METHODS AND MATERIALS

1973 genes associated with immune system were derived from the Immport database, and RNA-seq data of melanoma and information of patients were searched from the Xena database. Cox univariate analysis, Lasso analysis and Cox multivariate analysis were used to screen out six genes to construct the model. Then the risk scores were estimated for patients based on our constructed prognosis model. Estimate was used to affirm that the model was about immune infiltration, and CIBERSORT was used to screen out immune cells associated with prognosis. TIDE was applied to predict the efficacy of immunotherapy. Finally, GSE65904 and GSE19234 were used to confirm the effectiveness of the model.

RESULTS

ADCYAP1R1, GPI, NTS might cause poor prognosis while IFITM1, KIR2DL4, LIF were more likely conductive to prognosis of melanoma patients and a model of prognosis was constructed on the basis of these six genes. The effectiveness of the model has been proven by the ROC curve, and the miRNAs targeting the screened genes were found out, suggesting that the immune system might impact on the prognosis of melanoma by T cell CD8+, T cell CD4+ memory and NK cells.

CONCLUSIONS

In this study, the screened six genes were associated with the prognosis of melanoma, which was conductive to clinical prognostic prediction and individualized treatment strategy.

Integrated Analysis of miRNA and mRNA Regulation Network in Hypertension

Hypertension is the most common chronic disease. Early diagnosis is helpful for early medical intervention. The miRNAs and the messenger RNAs (mRNAs) network may be valuable disease diagnosis markers. We aimed to explore the diagnostic value of the miRNA-mRNA network for hypertension patients. Data of miRNAs and mRNAs expression were obtained from the Gene Expression Omnibus database. The weighted gene co-expression network analysis was performed to screen hypertension-related gene modules, and these genes undergone functional enrichment analysis using "clusterProfiler" package. Differential expression analysis was applied on miRNAs expression profiles using "limma" package. TargetScanHuman and miRDB databases were used to select target mRNAs. Cytoscape software was used to visualize the miRNA-mRNA regulation network. P value < 0.05 was considered statistically significant after t test. There were 123 screened mRNAs which were enriched in 161 Gene ontology (GO) terms and 14 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Thirty-five differentially expressed miRNAs (DEMs) are found in the GSE75670. Totally 36 miRNA-mRNA pairs were obtained after the integrated analysis, and three mRNAs and the hsa-miRNA-5589-5p were identified as key joints. Hub genes, KIAA0513, ARID3A and LRPAP1, and key hsa-miRNA-5589-5p are potential diagnostic biomarkers for hypertension. Our findings are promising in the clinical application, conducive to early detection and prompt intervention of hypertension.

Identification of the Key Genes of Immune Infiltration in Dilated Cardiomyopathy

Dilated cardiomyopathy (DCM) is a common cause of heart failure. In this study, we screened the immune infiltration-related genes associated with DCM to explore the potential molecular mechanisms and provide a basis for the early diagnosis and development of new immunotherapeutic targets. A dataset related to DCM was downloaded from the Gene Expression Omnibus (GEO) database. R software was applied to the genetic differential analysis of patients with DCM and healthy individuals, and the obtained differential expressed genes (DEGs) were screened for differentially expressed immune-related genes (DEIRGs) after comparison with the immune microsatellite database. Gene functional analysis established a protein interaction network (PPI). The immune infiltration in patients with DCM versus normal controls was assessed using the CIBERSORT algorithm, the hub genes were screened using the MOCDE app, and the hubs were validated in multiple datasets. A total of 246 DEGs were screened (adj. P < 0.05 and |logFC| > 0.3), and a total of 170 DEIRGs were compared. Gene Ontology analysis showed significant (adj. P < 0.05) Biological Process entries of 591, Cellular Component of 10, and Molecular Function of 39; Kyoto Encyclopedia of Genes and Genomes showed 20 significant entries, mainly focused on cytokines involved in immune-related response, etc. A protein interaction network comprising 28 hub DEGs was constructed in combination with the PPI network interactions. DEIRG was mainly distributed in the T-cell receptor pathway by immune infiltration detection analysis, and significant changes in central memory T-cells were found by analyzing T-cell-related subpathways, where INSR, HLA-B, IFITM1, and HBEGF were significantly differentially expressed. We selected 632 hospitalized patients for validation and found that INSR and HLA-B expression were associated with DCM development by Nomogram. The expression of HLA-B in peripheral blood T-cells was higher in DCM patients than in the normal group, as verified by qRT-PCR. However, the detailed mechanism needs to be further explored.

Characterization of lncRNA-associated ceRNA network to uncover novel potential biomarkers in coronary artery disease

The purpose of this study was to construct a competitive endogenous RNA (ceRNA) network related to long non-coding RNA (lncRNAs) via the bioinformatics analysis, reveal the pathogenesis of coronary heart disease (CAD) and develop new biomarkers for CAD. The gene expression datasets of peripheral blood of CAD were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed mRNAs, miRNAs and lncRNAs (DEmRNAs, DEmiRNAs and DElncRNAs) were identified. Subsequently, a ceRNA network involving lncRNAs, miRNAs, and mRNAs was built. Moreover, DElncRNAs in the cytoplasm were screened and a DElncRNA-associated ceRNA network was established. In total, 1860 DEmRNAs, 393 DElncRNAs and 20 DEmiRNAs were filtrated in patients with CAD compared with normal controls. Functional analysis suggested that DEmRNAs significantly enriched in CAD-related pathways, such as PI3K-Akt signaling pathways and MAPK signaling pathway. The ceRNA network contained 12 DEmiRNAs, 30 DElncRNAs and 537 DEmRNAs. Afterwards, the cytoplasm ceRNA network was consisted of 537 DEmRNAs, 12 DEmiRNAs and 12 DElncRNAs. Such as, up-regulated LncRNA-HOX transcript antisense RNA (HOTAIR) was interacted with down-regulated has-miR-326 and has-miR-1. The successful construction of lncRNA-associated ceRNA network is helpful to better clarify the pathogenesis of CAD and provide potential peripheral blood biomarkers for CAD.

Long non-coding RNA GAS5 promotes cisplatin-chemosensitivity of osteosarcoma cells via microRNA-26b-5p/TP53INP1 axis

Osteosarcoma is a common malignant bone tumor. Cisplatin (DDP) achieves a high response rate in osteosarcoma. Here we aim to study the dysregulation of long non-coding RNA the growth arrest-specific transcript 5 (GAS5), and its roles in DDP-resistance of osteosarcoma. The expression of mRNA and microRNA in osteosarcoma tissues and osteosarcoma cell lines were detected by quantitative reverse-transcription polymerase chain reaction, and protein expression levels were measured by western blotting assay. Cell Counting Kit-8 and 5-Ethynyl-2'-deoxyuridine were used to measure cell proliferation. Flow cytometer assay was used to evaluate cell apoptosis. The interactions between miR-26b-5p and GAS5 or tumor protein p53-induced nuclear protein 1 (TP53INP1) were verified by dual luciferase reporter along with biotin RNA pull-down assays. GAS5 was identified to be significantly lowly expressed in osteosarcoma samples especially in cisplatin-resistant (DDP-resistant) tissues. GAS5 was also downregulated in DDP-resistant cells. Over-expressed GAS5 prominently increased the sensitivity of osteosarcoma cells to DDP in vitro. Furthermore, over-expression of GAS5 suppressed cell proliferation and facilitated apoptosis of DDP-resistant cells. Mechanistically, GAS5 sponged miR-26b-5p, over-expression of which reversed the effects of GAS5 on cell proliferation and apoptosis of DDP-resistant cells. In addition, miR-26b-5p targeted TP53INP1. TP53INP1 abrogated the functions of miR-26b-5p on cell proliferation and apoptosis in DDP-resistant cells. Taken together, GAS5 enhanced the sensitivity of osteosarcoma cells to DDP via GAS5/miR-26b-5p/TP53INP1 axis. Therefore, GAS5 may be a potential indicator for the management of osteosarcoma.

Hsa_ circ_0006867 regulates ox-LDL-induced endothelial injury via the miR-499a-3p/ADAM10 axis

Circular RNAs (circRNAs) have been reported to participate in the development of various diseases. In this study, we investigated the potential mechanism underlying the role of circRNAs in atherosclerosis. Human umbilical vein endothelial cells (HUVECs) were treated with 100μg/mL oxidized low-density lipoprotein (ox-LDL) to simulate atherosclerosis. We observed that hsa_circ_0006867 (circ_0006867), a circRNA markedly increased in ox-LDL-treated endothelial cells, acted as a molecular sponge of miR-499a-3p and regulated its expression. This interaction led to changes in the downstream target gene ADAM10, thus affecting cell apoptosis and migration. Thus, our study suggests that circ_0006867 regulates ox-LDL-induced endothelial injury via the circ_0006867/miR-499a-3p/ADAM10 axis, indicating its potential as an exploitable therapeutic target for atherosclerosis.

Diagnostic value of circRNA in coronary heart disease: a meta-analysis

Aim: Studies have indicated that circRNAs have diagnostic value for coronary heart disease (CHD), but the efficacy varies greatly; therefore, a meta-analysis was conducted to assess the diagnostic value of circRNAs in CHD. Materials & methods: 16 studies with 3962 subjects (2239 cases and 1723 controls) were included by searching PubMed, Web of Science and MEDLINE. The pooled sensitivity and specificity, summary receiver operating characteristic and area under the curve, positive likelihood ratio and negative likelihood ratio were calculated. Results: The pooled area under the curve of circRNAs for the diagnosis of CHD was 0.80 (sensitivity and specificity were 0.77 and 0.68, respectively), and more indexes were calculated. Conclusion: circRNAs may be good biomarkers for diagnosing CHD.

Circular RNA circSLC7A11 contributes to progression and stemness of laryngeal squamous cell carcinoma via sponging miR-877-5p from LASP1

Background

Laryngeal squamous cell carcinoma (LSCC) belongs to tumors of head and neck. Circular RNA circSLC7A11 functions as oncogenes in various tumors. However, the role of circSLC7A11 in LSCC remains largely unknown. Here, we aimed to clarify the circSLC7A11 function in LSCC.

Methods

Relevance between circSLC7A11 expressions and LSCC clinicopathological was checked using chi-square. Relevance between circSLC7A11 expressions and LSCC patients' survival time was validated using Kaplan-Meier analysis. CircSLC7A11 expressions in LSCC tissues and cells were determined using quantitative real-time PCR. CircSLC7A11 functions in LSCC were examined by Cell Counting Kit-8, EdU analysis, Western blot, flow cytometry, sphere formation assay, and Transwell analysis. Meanwhile, circSLC7A11 mechanism in LSCC was determined using dual-luciferase reporter analysis, RNA pull-down, RNA Immunoprecipitation.

Results

CircSLC7A11 was highly expressed in LSCC, and high circSLC7A11 expressions were interrelated to the TNM stage. Also, LSCC patients with high circSLC7A11 owned shorter overall survival. Functional studies revealed that circSLC7A11 knockdown reduced LSCC cell proliferation, migration, invasion, stemness characteristics, and enhanced cell apoptosis. Mechanistic study data corroborated that circSLC7A11 targeted miR-877-5p, miR-877-5p targeted LASP1. LASP1 was negatively interrelated to miR-877-5p and was positively interrelated to circSLC7A11 in LSCC tissues. Also, circSLC7A11 knockdown reduced the LASP1 levels, and miR-877-5p inhibitor co-transfection reversed this reduction. Rescue assays further demonstrated that circSLC7A11 accelerated LSCC through miR-877-5p/LASP1.

Conclusion

CircSLC7A11 exerted oncogenic functions in LSCC by miR-877-5p/LASP1, hinting that circSLC7A11 was a novel biomarker for LSCC.

CircRNA_0026344 via miR-21 is involved in cigarette smoke-induced autophagy and apoptosis of alveolar epithelial cells in emphysema

Cigarette smoke (CS), a main source of indoor air pollution, is a primary risk factor for emphysema, and aberrant cellular autophagy is related to the pathogenesis of emphysema. Circular RNAs (circRNAs) affect the expression of mRNAs via acting as microRNA (miRNA) sponges, but their role in emphysema progression is not established. In the present investigation, CS, acting on alveolar epithelial cells, caused higher levels of miR-21, p-ERK, and cleaved-caspase 3 and led to lower levels of circRNA_0026344 and PTEN, which induced autophagy and apoptosis. miR-21 suppressed the expression of PTEN, which was involved in the regulation of autophagy and apoptosis. Further, in alveolar epithelial cells, overexpression of circRNA_0026344 blocked cigarette smoke extract (CSE)-induced autophagy and apoptosis, but this blockage was reversed by upregulation of miR-21 with a mimic. These results demonstrated that, in alveolar epithelial cells, CS decreases circRNA_0026344 levels, which sponge miR-21 to inhibit the miR-21 target, PTEN, which, in turn, activates ERK and thereby promotes autophagy and apoptosis, leading to emphysema. Thus, for emphysema, circRNA_0026344 regulates the PTEN/ERK axis by sponging miR-21, which is associated with the CS-induced autophagy and apoptosis of alveolar epithelial cells. In sum, the present investigation identifies a novel mechanism for CS-induced emphysema and provides information useful for the diagnosis and treatment of CS-induced emphysema.

BTG2 and SerpinB5, a novel gene pair to evaluate the prognosis of lung adenocarcinoma

Introduction

Lung adenocarcinoma (LUAD), as the most frequent pathological subtype of non−small cell lung cancer, is often characterized by poor prognosis and low 5-year survival rate. Exploriton of new biomarkers and accurate molecular mechanisms for effectively predicting the prognosis of LUAD patients is still necessary. Presently, BTG2 and SerpinB5, which play important roles in tumors, are studied as a gene pair for the first time with the aim of exploring whether they can be used as potential prognostic markers.

Methods

Using the bioinformatics method to explore whether BTG2 and SerpinB5 can become independent prognostic factors, and explore their clinical application value and whether they can be used as immunotherapeutic markers. In addition, we also verify the conclusions obtained from external datasets, molecular docking, and SqRT-PCR.

Results

The results show that compared with normal lung tissue, BTG2 expression level was down-regulated and SerpinB5 was up-regulated in LUAD. Additionally, Kaplan–Meier survival analysis demonstrate that the prognosis of low expression level of BTG2 was poor, and that of high expression level of SerpinB5 was poor, suggesting that both of them can be used as independent prognostic factors. Moreover, the prognosis models of the two genes were constructed respectively in this study, and their prediction effect was verified by external data. Besides, ESTIMATE algorithm reveals the relationship between this gene pair and the immune microenvironment. Furthermore, patients with a high expression level of BTG2 and a low expression level of SerpinB5 have higher immunophenoscore for CTLA-4 and PD-1 inhibitors than patients with a low expression level of BTG2 and a high expression level of SerpinB5, indicating that such patients have a more obvious effect of immunotherapy.

Discussion

Collectively, all the results demonstrate that BTG2 and SerpinB5 might serve as potential prognostic biomarkers and novel therapeutic targets for LUAD.

Identification of hsa_circ_0001445 of a novel circRNA-miRNA-mRNA regulatory network as potential biomarker for coronary heart disease

Objects

To evaluate the hsa_circ_0001445 level in peripheral blood leukocytes of patients with coronary heart disease (CHD) and its related clinical factors, and predict its circRNA-miRNA-mRNA regulatory network in CHD pathogenesis via bioinformatics analysis.

Methods

Peripheral blood leukocytes were isolated from the whole blood samples of 94 CHD patients (aged 65.96 ± 9.78 years old) and 126 healthy controls (aged 60.75 ± 8.81 years old). qRT-PCR was used to quantify the expression level of circRNA and subsequently analyze its association with CHD clinical parameters. Via bioinformatics algorithm and GEO datasets, differential miRNA expression was evaluated using the Limma package. A miRNA-mRNA regulatory network was predicted by cyTargetLinker. ClusterProfiler was employed to perform functional enrichment analysis of the circRNA network to investigate its role in CHD pathogenesis.

Results

The expression of hsa_circ_0001445 in peripheral blood leukocytes of CHD patients was downregulated compared with that of healthy controls. Positive correlations were evident between hsa_circ_0001445 expression level and the levels of hemoglobin, triglycerides, high- and low-density lipoprotein cholesterol. A significant negative correlation was also found between hsa_circ_0001445 expression level and age and the neutrophil level. Low expression of hsa_circ_0001445 exhibited a discriminatory ability between CHD patients and healthy controls with a sensitivity of 67.5% and a specificity of 76.6% (p &lt; 0.05). By bioinformatics analysis, 405 gene ontology terms were identified. The Kyoto Encyclopedia of Genes and Genomes terms focused principally on the PI3K-Akt signaling pathway. hsa_circ_0001445 was associated with the expression of three miRNAs that may regulate 18 genes involved in KEGG processes: hsa-miR-507, hsa-miR-375–3p, and hsa-miR-942–5p.

Conclusion

The hsa_circ_0001445 level in peripheral blood leukocytes may serve as a biomarker for CHD diagnosis. Our work on circRNA-miRNA-mRNA networks suggests a potential role for hsa_circ_0001445 in CHD development.

Diagnostic value of peripheral blood miR-296 combined with vascular endothelial growth factor B on the degree of coronary artery stenosis in patients with coronary heart disease

OBJECTIVE

Coronary heart disease (CHD) is a disorder resulting from organic and functional coronary artery stenosis (CAS), thus causing reduced oxygenated blood in the heart. miRNAs are useful biomarkers in the diagnosis of atherosclerosis, CHD, and acute coronary syndrome. Vascular endothelial growth factor (VEGF) is closely related to CHD. This study explored the correlation of miR-296 and VEGF-B expression levels in peripheral blood with CAS degree in CHD patients.

METHODS

Totally 220 CHD patients were enrolled and classified into mild-(71 cases)/moderate-(81 cases)/severe-CAS (68 cases) groups, with another 80 healthy cases as controls. The serum miR-296 and VEGF-B expression levels were detected using reverse transcription quantitative polymerase chain reaction. The correlation between miR-296 and CAS-related indexes was assessed via Pearson analysis. The binding relationship of miR-296 and VEGF-B was first predicted and their correlation was further analyzed via the Pearson method. The clinical diagnostic efficacy of miR-296 or VEGF-B on CAS degree was evaluated by the receiver operating characteristic curve.

RESULTS

Serum miR-296 was downregulated in CHD patients and was the lowest in patients with severe-CAS. miR-296 was negatively-correlated with high-sensitivity C-reactive protein, brain natriuretic peptide, and cardiac troponin I. miR-296 targeted VEGF-B. VEGF-B was upregulated in CHD patients and inversely-related to miR-296. Low expression of miR-296 and high expression of VEGF-B both had high clinical diagnostic values on CAS degree in CHD patients. miR-296 combined with VEGF-B increased the diagnostic value on CAS.

CONCLUSION

Low expression of miR-296 combined with high expression of its target VEGF-B predicts CAS degree in CHD patients.

Expression Pattern and Molecular Mechanism of Oxidative Stress-Related Genes in Myocardial Ischemia-Reperfusion Injury

(1) Background: The molecular mechanism of oxidative stress-related genes (OSRGs) in myocardial ischemia-reperfusion injury (MIRI) has not been fully elucidated. (2) Methods: Differential expression analysis, enrichment analysis, and PPI analysis were performed on the MIRI-related datasets GSE160516 and GSE61592 to find key pathways and hub genes. OSRGs were obtained from the Molecular Signatures Database (MSigDB). The expression pattern and time changes of them were studied on the basis of their raw expression data. Corresponding online databases were used to predict miRNAs, transcription factors (TFs), and therapeutic drugs targeting common differentially expressed OSRGs. These identified OSRGs were further verified in the external dataset GSE4105 and H9C2 cell hypoxia-reoxygenation (HR) model. (3) Results: A total of 134 DEGs of MIRI were identified which were enriched in the pathways of "immune response", "inflammatory response", "neutrophil chemotaxis", "phagosome", and "platelet activation". Six hub genes and 12 common differentially expressed OSRGs were identified. A total of 168 miRNAs, 41 TFs, and 21 therapeutic drugs were predicted targeting these OSRGs. Lastly, the expression trends of Aif1, Apoe, Arg1, Col1a1, Gpx7, and Hmox1 were confirmed in the external dataset and HR model. (4) Conclusions: Aif1, Apoe, Arg1, Col1a1, Gpx7, and Hmox1 may be involved in the oxidative stress mechanism of MIRI, and the intervention of these genes may be a potential therapeutic strategy.

Silencing hsa_circ_0049271 attenuates hypoxia-reoxygenation (H/R)-induced myocardial cell injury via the miR-17-3p/FZD4 signaling axis

Background

This study sought to explore the role and molecular mechanism of circ_0049271 in hypoxia-reoxygenation (H/R)-induced cardiomyocyte injury.

Methods

Significantly upregulated circular ribonucleic acids (circRNAs) in Gene Expression Omnibus (GEO) data sets were identified using a Venn diagram. A H9c2 (rat cardiomyocytes) cell model of acute myocardial infarction (AMI) was induced by 1% H/R. Quantitative reverse transcription-polymerase chain reaction was used to detect the expression levels of circ_0049271, miR-17-3p, and FZD4 in clinical blood samples and cells, and Cell Counting Kit-8 (CCK-8) was used to determine the proliferation rate of the cells in each group. Next, flow cytometry and Western blot were used to evaluate cell apoptosis. Biochemical tests and enzyme-linked immunosorbent assays (ELISAs) were then used to determine the activities/levels of the cell damage markers [i.e., creatine kinase (CK) and lactate dehydrogenase (LDH)], oxidative stress substances [i.e., malondialdehyde (MDA), reactive oxygen species (ROS), and superoxide dismutase (SOD)], and inflammatory factors [i.e., interleukin (IL)-1β, IL-6, and IL-8]. In addition, intermolecular interactions were verified using dual-luciferase reporter and RNA pull-down experiments.

Results

Circ_0049271 was significantly upregulated in both the blood of the AMI patients and the H/R-induced H9c2 cells. The knockdown of circ_0049271 increased the cell proliferation rate, decreased the apoptosis rate, inhibited oxidative stress (ROS and MDA were upregulated, and SOD was downregulated) and inflammatory responses (IL-1, IL-6, and IL-8 were downregulated), and relieved cell damage. However, the overexpression of circ_0049271 promoted H/R-induced H9c2 cell damage. Further experiments showed that miR-17-3p was a target of circ_0049271, and miR-17-3p was negatively correlated with circ_0049271 in the AMI blood samples. Additionally, miR-17-3p was found to target FZD4. A further exploration also revealed that miR-17-3p knockdown or FZD4 overexpression reversed the effects of si-circ_0049271 on the H/R-induced H9c2 cells; that is, miR-17-3p knockdown or FZD4 overexpression promoted H/R-induced injury in the H9c2 cells.

Conclusions

Circ_0049271 promoted cellular function damage (e.g., proliferation inhibition, apoptosis, oxidative stress, and inflammation) in H/R-induced H9c2 cardiomyocytes via the miR-17-3p/FZD4 signaling axis.

Circular RNAs as a Diagnostic and Therapeutic Target in Cardiovascular Diseases

Circular RNAs (circRNAs) are a family of noncoding RNAs (ncRNAs) that are endogenous and widely distributed in different species, performing several functions, mainly their association with microRNAs (miRNAs) and RNA-binding proteins. CVDs remain the leading cause of death worldwide; therefore, the development of new therapies and strategies, such as gene therapies or nonpharmacological therapies, with low cost, such as physical exercise, to alleviate these diseases is of extreme importance for society. With increasing evidence of ncRNA participating in the progression of CVDs, several studies have reported these RNAs as promising targets for diagnosis and treatment. There are several studies of CVDs and the role of miRNAs and lncRNAs; however, little is known about the new class of RNAs, called circRNAs, and CVDs. In this mini review, we focus on the mechanisms of circRNAs and CVDs.

In-depth systems biological evaluation of bovine alveolar macrophages suggests novel insights into molecular mechanisms underlying Mycobacterium bovis infection

OBJECTIVE

Bovine tuberculosis (bTB) is a chronic respiratory infectious disease of domestic livestock caused by intracellular Mycobacterium bovis infection, which causes ~$3 billion in annual losses to global agriculture. Providing novel tools for bTB managements requires a comprehensive understanding of the molecular regulatory mechanisms underlying the M. bovis infection. Nevertheless, a combination of different bioinformatics and systems biology methods was used in this study in order to clearly understand the molecular regulatory mechanisms of bTB, especially the immunomodulatory mechanisms of M. bovis infection.

METHODS

RNA-seq data were retrieved and processed from 78 (39 non-infected control vs. 39 M. bovis-infected samples) bovine alveolar macrophages (bAMs). Next, weighted gene co-expression network analysis (WGCNA) was performed to identify the co-expression modules in non-infected control bAMs as reference set. The WGCNA module preservation approach was then used to identify non-preserved modules between non-infected controls and M. bovis-infected samples (test set). Additionally, functional enrichment analysis was used to investigate the biological behavior of the non-preserved modules and to identify bTB-specific non-preserved modules. Co-expressed hub genes were identified based on module membership (MM) criteria of WGCNA in the non-preserved modules and then integrated with protein-protein interaction (PPI) networks to identify co-expressed hub genes/transcription factors (TFs) with the highest maximal clique centrality (MCC) score (hub-central genes).

RESULTS

As result, WGCNA analysis led to the identification of 21 modules in the non-infected control bAMs (reference set), among which the topological properties of 14 modules were altered in the M. bovis-infected bAMs (test set). Interestingly, 7 of the 14 non-preserved modules were directly related to the molecular mechanisms underlying the host immune response, immunosuppressive mechanisms of M. bovis, and bTB development. Moreover, among the co-expressed hub genes and TFs of the bTB-specific non-preserved modules, 260 genes/TFs had double centrality in both co-expression and PPI networks and played a crucial role in bAMs-M. bovis interactions. Some of these hub-central genes/TFs, including PSMC4, SRC, BCL2L1, VPS11, MDM2, IRF1, CDKN1A, NLRP3, TLR2, MMP9, ZAP70, LCK, TNF, CCL4, MMP1, CTLA4, ITK, IL6, IL1A, IL1B, CCL20, CD3E, NFKB1, EDN1, STAT1, TIMP1, PTGS2, TNFAIP3, BIRC3, MAPK8, VEGFA, VPS18, ICAM1, TBK1, CTSS, IL10, ACAA1, VPS33B, and HIF1A, had potential targets for inducing immunomodulatory mechanisms by M. bovis to evade the host defense response.

CONCLUSION

The present study provides an in-depth insight into the molecular regulatory mechanisms behind M. bovis infection through biological investigation of the candidate non-preserved modules directly related to bTB development. Furthermore, several hub-central genes/TFs were identified that were significant in determining the fate of M. bovis infection and could be promising targets for developing novel anti-bTB therapies and diagnosis strategies.

Epigenetics: a new warrior against cardiovascular calcification, a forerunner in modern lifestyle diseases

Arterial and aortic valve calcifications are the most prevalent pathophysiological conditions among all the reported cases of cardiovascular calcifications. It increases with several risk factors like age, hypertension, external stimuli, mechanical forces, lipid deposition, malfunction of genes and signaling pathways, enhancement of naturally occurring calcium inhibitors, and many others. Modern-day lifestyle is affected by numerous environmental factors and harmful toxins that impair our health rather than providing benefits. Applying the combinatorial approach or targeting the exact mechanism could be a new strategy for drug designing or attenuating the severity of calcification. Most of the non-communicable diseases are life-threatening; thus, altering the phenotype and not the genotype may reveal the gateway for fighting with upcoming hurdles. Overall, this review summarizes the reason behind the generation of arterial and aortic valve calcification and its related signaling pathways and also the detrimental effects of calcification. In addition, the individual process of epigenetics and how the implementation of this process becomes a novel approach for diminishing the harmful effect of calcification are discussed. Noteworthy, as epigenetics is linked with genetics and environmental factors necessitates further clinical trials for complete and in-depth understanding and application of this strategy in a more specific and prudent manner.

Circ_0114428 promotes proliferation, fibrosis and EMT process of high glucose-induced glomerular mesangial cells through regulating the miR-185-5p/SMAD3 axis

Circular RNA (circRNA) has been confirmed to be the key regulators of diabetic nephropathy (DN) progression. However, the role of circ_0114428 in the DN progression remains unclear. Glomerular mesangial cells (GMCs) were treated with high glucose (HG) to mimic DN cell models in vitro. The expression levels of circ_0114428, microRNA (miR)-185-5p, and SMAD3 mRNA were examined by quantitative real-time PCR. Cell proliferation ability was detected by MTT assay, EdU staining and flow cytometry. The protein levels of proliferation marker, fibrosis markers, epithelial-mesenchymal transition (EMT) markers and SMAD3 were measured by western blot assay. The interaction between miR-185-5p and circ_0114428 or SMAD3 was confirmed via dual-luciferase reporter assay, RIP assay and RNA pull-down assay. Our data showed that circ_0114428 was upregulated in HG-induced GMCs. Circ_0114428 overexpression could aggravate the promotion effect of HG on the proliferation, fibrosis and EMT process of GMCs, while its knockdown had an opposite effect. In the terms of mechanisms, circ_0114428 could sponge miR-185-5p to regulate SMAD3. MiR-185-5p inhibitor could reverse the suppressive effect of circ_0114428 knockdown on the proliferation, fibrosis and EMT process in HG-induced GMCs. Also, SMAD3 overexpression abolished the inhibition of miR-185-5p on the proliferation, fibrosis and EMT process in HG-induced GMCs. Taken together, our data suggested that circ_0114428 might promote DN progression by regulating the miR-185-5p/SMAD3 axis.

Comprehensive Analysis of circRNA-miRNA-mRNA Regulatory Network and Novel Potential Biomarkers in Acute Myocardial Infarction

Background

Circular RNA (circRNA) plays an important role in the regulation of gene expression and the occurrence of human diseases. However, studies on the role of circRNA in acute myocardial infarction (AMI) are limited. This study was performed to explore novel circRNA-related regulatory networks in AMI, aiming to better understand the molecular mechanism of circRNAs involvement in AMI and provide basis for further scientific research and clinical decision-making.

Methods

The AMI-related microarray datasets GSE160717 (circRNA), GSE31568 (miRNA), GSE61741 (miRNA), and GSE24519 (mRNA) were obtained from the Gene Expression Omnibus (GEO) database. After differential expression analysis, the regulatory relationships between these DERNAs were identified by online databases circBank, circInteractome, miRDB, miRWalk, Targetscan, and then two circRNA-miRNA-mRNA regulatory networks were constructed. Differentially expressed genes (DEGs) in this network were selected followed by enrichment analysis and protein–protein interaction (PPI) analysis. Hub genes were identified using Cytohubba plug-in of Cytoscape software. Hub genes and hub gene-related miRNAs were used for receiver operating characteristic curve (ROC) analysis to identify potential biomarkers. The relative expression levels of these biomarkers were further assessed by GSE31568 (miRNA) and GSE66360 (mRNA). Finally, on the basis of the above analysis, myocardial hypoxia model was constructed to verify the expression of Hub genes and related circRNAs.

Results

A total of 83 DEcircRNAs, 109 CoDEmiRNAs and 1204 DEGs were significantly differentially expressed in these datasets. The up-regulated circRNAs and down-regulated circRNAs were used to construct a circRNA-miRNA-mRNA regulatory network respectively. These circRNA-related DEGs were mainly enriched in the terms of “FOXO signaling pathway,” “T cell receptor signaling pathway,” “MAPK signaling pathway,” “Insulin resistance,” “cAMP signaling pathway,” and “mTOR signaling pathway.” The top 10 hub genes ATP2B2, KCNA1, GRIN2A, SCN2B, GPM6A, CACNA1E, HDAC2, SRSF1, ANK2, and HNRNPA2B1 were identified from the PPI network. Hub genes GPM6A, SRSF1, ANK2 and hub gene-related circRNAs hsa_circ_0023461, hsa_circ_0004561, hsa_circ_0001147, hsa_circ_0004771, hsa_circ_0061276, and hsa_circ_0045519 were identified as potential biomarkers in AMI.

Conclusion

In this study, the potential circRNAs associated with AMI were identified and two circRNA-miRNA-mRNA regulatory networks were constructed. This study explored the mechanism of circRNA involvement in AMI and provided new clues for the selection of new diagnostic markers and therapeutic targets for AMI.

CircLDLR Modulates the Proliferation and Apoptosis of Vascular Smooth Muscle Cells in Coronary Artery Disease Through miR-26-5p/KDM6A Axis

ABSTRACT

The purpose of this study was to investigate the effect of circLDLR on the proliferation and apoptosis of vascular smooth muscle cells (VSMCs) in coronary artery disease and its regulatory mechanism. The expression of KDM6A was detected by qRT-PCR or Western blot. VSMCs were transfected with miR-26-5p mimic/inhibitor or OE KDM6A. Cell proliferation and apoptosis were assessed. Luciferase reporter gene assays were used to examine interactions between miR-26-5p and KDM6A in VSMCs. Downregulation of circLDLR was associated with increased miR-26-5p in coronary artery disease tissues. In addition, circLDLR could inhibit cell proliferation and promote cell apoptosis by regulating miR-26-5p. Moreover, the overexpression of KDM6A reduced VSMCs proliferation and increased apoptosis in an miR-26-5p/circLDLR axis-dependent manner. CircLDLR modulates the proliferation and apoptosis of VSMCs through miR-26-5p/KDM6A axis.

Circ_ROBO2/miR-186-5p/TRIM14 axis regulates oxidized low-density lipoprotein-induced cardiac microvascular endothelial cell injury

Background

Coronary artery disease (CAD) is one of the main risks of death, which is mainly caused by coronary arteries arteriosclerosis. Circular RNAs (circRNAs) have shown important regulatory roles in cardiovascular diseases. We amid to explore the role of circ_ROBO2 in CAD.

Methods

Cardiac microvascular endothelial cells (CMECs) stimulated by oxidized low-density lipoprotein (ox-LDL) were served as the cellular model of CAD. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot assay were performed to detect RNA levels and protein levels, respectively. Cell proliferation was assessed by 5-ethynyl-2′-deoxyuridine (EdU) assay and Cell Counting Kit-8 (CCK-8) assay. Flow cytometry was employed for measuring cell apoptosis. Matrigel tube formation assay was used to evaluate angiogenesis ability. The intermolecular interaction was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA-pull down assays.

Results

The expression of circ_ROBO2 was upregulated in CAD patients and ox-LDL-induced CMECs. Treatment of ox-LDL suppressed cell proliferation and angiogenic ability as well as promoted the apoptosis of CMECs partly by upregulating circ_ROBO2. MicroRNA-186-5p (miR-186-5p) was identified as a target of circ_ROBO2, and circ_ROBO2 knockdown attenuated ox-LDL-induced damage in CMECs by sponging miR-186-5p. Tripartite motif containing 14 (TRIM14) acted as a target of miR-186-5p, and TRIM14 overexpression alleviated miR-186-5p-mediated inhibitory effect on ox-LDL-induced injury in CMECs. Circ_ROBO2 positively regulated TRIM14 expression by sponging miR-186-5p.

Conclusion

Circ_ROBO2 played a promoting role in ox-LDL-induced CMECs injury by sponging miR-186-5p and regulating TRIM14, providing a promising treatment strategy for CAD.

Circular RNA circ_0006089 regulates the IGF1R expression by targeting miR-143-3p to promote gastric cancer proliferation, migration and invasion

Circular RNAs (circRNAs) figure prominently in regulating the progression of a variety of human malignancies. This study was performed to probe how circ_0006089 functioned in gastric cancer (GC). CircRNA expression profile GSE83521 was downloaded from Gene Expression Omnibus (GEO) database, and circRNAs and analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure circ_0006089, microRNA-143-3p (miR-143-3p) and insulin-like growth factor 1 receptor (IGF1R) mRNA expressions in GC tissues and cell lines. Kaplan-Meier curves were used to detect the relationship between circ_0006089 expression and overall survival time of GC patients. Cell counting kit-8 (CCK-8) and 5-bromo-2-deoxyuridine (BrdU) assays were employed to detect the proliferative ability of GC cells after circ_0006089 was overexpressed or knocked down. Wound healing assay and Transwell assay were executed to examine the migration and invasion ability of GC cells. Western blot was adopted to detect IGF1R protein expressions. Circ_0006089 expression was up-regulated in GC samples and cell lines. And high circ_0006089 expression was associated with shorter survival time in GC patients. Circ_0006089 overexpression in GC cells significantly accelerated GC cell proliferation, migration and invasion, whereas circ_0006089 knockdown resulted in the opposite effects. Additionally, miR-143-3p was validated as a downstream target of circ_0006089, and circ_0006089 could positively regulate IGF1R expression via repressing miR-143-3p. Circ_0006089 is highly expressed in GC, and it promotes the malignancy of GC cells via modulating miR-143-3p/IGF1R axis, suggesting that circ_0006089 may serve as a promising therapeutic target for GC.

Diagnostic value of miRNA expression and right ventricular echocardiographic functional parameters for chronic thromboembolic pulmonary hypertension with right ventricular dysfunction and injury

Background

We aimed to establish the relationships between the expression of microRNAs (miRNAs) and echocardiographic right ventricular (RV) function parameters, and to explore the effectiveness and clinical value of miRNA expression in predicting RV injury and dysfunction in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

Methods

In this retrospective study, clinical data were collected from eight CTEPH patients and eight healthy individuals. RV parameters on echocardiography were analyzed, and the expression levels of specific miRNAs were measured by quantitative real-time PCR. Correlation analysis was performed on structural and functional RV parameters and five candidate miRNAs (miR-20a-5p, miR-17-5p, miR-93-5p, miR-3202 and miR-665). The diagnostic value of RV functional parameters and miRNAs expression was assessed by receiver operating characteristic (ROC) curve analysis and C statistic.

Results

Among the tested miRNAs, miR-20a-5p expression showed the best correlation with echocardiographic RV functional parameters (P < 0.05), although the expression levels of miR-93-5p, miR-17-5p and miR-3202 showed positive associations with some RV parameters. ROC curve analysis demonstrated the ability of miR-20a-5p expression to predict RV dysfunction, with a maximum area under the curve of 0.952 (P = 0.003) when the predicted RV longitudinal strain was less than –20%. The C index for RV dysfunction prediction by the combination of miRNAs (miR-20a-5p, miR-93-5p and miR-17-5p) was 1.0, which was significantly larger than the values for miR-93-5p and miR-17-5p individually (P = 0.0337 and 0.0453, respectively).

Conclusion

Among the tested miRNAs, miR -20a-5p, miR -93-5p and miR -17-5p have potential value in the diagnosis of CTEPH based on the correlation between the abnormal expression of these miRNAs and echocardiographic parameters in CTEPH patients. miR-20a-5p showed the strongest correlation with echocardiographic RV functional parameters. Moreover, expression of a combination of miRNAs seemed to show excellent predictive power for RV dysfunction.

The role of circRNAs in the regulation of myocardial angiogenesis in coronary heart disease

During myocardial ischemia, timely reperfusion is critical to limit infarct area and the overall loss of cardiac contractile function. New treatment strategies need to be developed for patients who are neither able to receive interventional treatment nor suitable for surgical blood transport reconstruction surgery. Therapeutic angiogenesis is a promising approach that can be used to guide new treatment strategies. The goal of these therapies is to form new blood vessels or promote the maturation of existing vasculature systems, bypassing blocked arteries to maintain organ perfusion, thereby relieving symptoms and preventing the remodeling of bad organs. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), have been attracted much attention for their roles in various physiological and pathological processes. There is growing evidence that ncRNAs, especially circRNAs, play an important role in the regulation of cardiomyopathy angiogenesis due to its diversity of functions. Therefore, this article reviews the role and mechanisms of circRNA in myocardial angiogenesis to better understand the role of circRNAs in myocardial angiogenesis, which may provide useful insights and new revelations for the research field of identifying diagnostic markers and therapeutic approaches for the treatment of coronary artery disease.

Bioinformatics approach to identify common gene signatures of patients with coronavirus 2019 and lung adenocarcinoma

Coronavirus disease 2019 (COVID-19) continues as a global pandemic. Patients with lung cancer infected with COVID-19 may develop severe disease or die. Treating such patients severely burdens overwhelmed healthcare systems. Here, we identified potential pathological mechanisms shared between patients with COVID-19 and lung adenocarcinoma (LUAD). Co-expressed, differentially expressed genes (DEGs) in patients with COVID-19 and LUAD were identified and used to construct a protein-protein interaction (PPI) network and to perform enrichment analysis. We used the NetworkAnalyst platform to establish a co-regulatory of the co-expressed DEGs, and we used Spearman's correlation to evaluate the significance of associations of hub genes with immune infiltration and immune checkpoints. Analysis of three datasets identified 112 shared DEGs, which were used to construct a protein-PPI network. Subsequent enrichment analysis revealed co-expressed genes related to biological process (BP), molecular function (MF), and cellular component (CC) as well as to pathways, specific organs, cells, and diseases. Ten co-expressed hub genes were employed to construct a gene-miRNA, transcription factor (TF)-gene, and TF-miRNA network. Hub genes were significantly associated with immune infiltration and immune checkpoints. Finally, methylation level of hub genes in LUAD was obtained via UALCAN database. The present multi-dimensional study reveals commonality in specific gene expression by patients with COVID-19 and LUAD. These findings provide insights into developing strategies for optimising the management and treatment of patients with LUAD with COVID-19.

The Role of Extracellular Non-coding RNAs in Atherosclerosis

Atherosclerosis (AS) is a complex chronic inflammatory disease that leads to myocardial infarction, stroke, and disabling peripheral artery disease. Non-coding RNAs (ncRNAs) directly participate in various physiological processes and exhibit a wide range of biological functions. The present review discusses how different ncRNAs participate in the process of AS in various carrier forms. We focused on the role and potential mechanisms of extracellular ncRNAs in AS and examined their potential implications for clinical treatment.

Construction of a circRNA-miRNA-mRNA Regulatory Network for Coronary Artery Disease by Bioinformatics Analysis

Background. Circular RNAs (circRNAs) were known to be related to the pathogenesis of many diseases through competing endogenous RNA (ceRNA) regulatory mechanisms. However, the function of circRNA in coronary artery disease (CAD) remains unclear. In this study, we aim to construct a circRNA-related competing endogenous RNA (ceRNA) network in CAD. Methods. The gene expression profiles of CAD were obtained from Gene Expression Omnibus datasets. Bioinformatics analysis was performed to construct a ceRNA regulatory network, from which the hub genes involved were identified through protein-protein interaction (PPI) networks leading to the identification of the circRNA-miRNA-hub gene subnetwork. In addition, function enrichment analysis was performed to detect the potential biological mechanism in which circRNA might be involved. Results. A total of 115 DEcircRNAs (differentially expressed circRNAs), 17 DEmiRNAs (differentially expressed microRNAs), and 790 DEmRNAs (differentially expressed mRNAs) were identified between CAD and control groups from microarray datasets. Functional enrichment analysis showed that DEmRNAs were significantly involved in inflammation-related pathways and ubiquitin-protein ligase binding. After identifying 20 DEcircRNA-DEmiRNA pairs and 561 DEmiRNA-DEmRNA pairs, we obtained a circRNA-miRNA-mRNA regulatory network. PPI network analysis showed that eight hub genes were closely related to CAD, leading to the identification of a circRNA-miRNA-hub gene subnetwork consisting of nine circRNAs (hsa_circ_0020275, hsa_circ_0020387, hsa_circ_0020417, hsa_circ_0045512, hsa_circ_0047336, hsa_circ_0069094, hsa_circ_0071326, hsa_circ_0071330, and hsa_circ_0085340), four miRNAs (hsa-miR-136-5p, hsa-miR-376c-3p, hsa-miR-411-5p, and hsa-miR-654-5p), and eight mRNAs (MKRN1, UBE2H, UBE2W, UBE2D1, UBE2F, BE2J1, ZNRF1, and SIAH2). In addition, we discovered these hub genes were enriched in the ubiquitin-mediated proteolysis pathway, suggesting circRNAs may be involved in the pathogenesis of CAD through this pathway. Conclusions. This study may deepen our understanding of the potential role of circRNA-miRNA-mRNA regulation network in CAD and suggest novel diagnostic biomarkers and therapeutic targets for CAD.

Inhibition of circular RNA circ_0138959 alleviates pyroptosis of human gingival fibroblasts via the microRNA-527/caspase-5 axis

Circular RNA (circRNA) plays a regulatory role in periodontitis. This study explored whether circ_0138959 affected lipopolysaccharide (LPS)-induced pyroptosis in human gingival fibroblasts (HGFs). The periodontal ligament (PDL) tissues and HGFs were derived from patients with periodontitis and healthy volunteers. HGFs treated with LPS were considered to mimic periodontitis in vitro. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to evaluate the mRNA expression levels of circRNAs, miR-527, and caspase-5 (CASP5), and Western blotting assay was used to measure protein expression levels of caspase-1, caspase-4, and cleaved N-terminal gasdermin D (GSDMD-N). Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. The concentration of lactate dehydrogenase (LDH), interleukin (IL)-1β, and IL-18 and the pyroptosis rate were determined to evaluate pyroptosis. The interaction between miR-527 and circ_0138959 or CASP5 was verified by dual-luciferase reporter and RNA pull-down assays. Circ_0138959 expression was higher in the PDL tissues of patients with periodontitis than in the healthy group; likewise, circ_0138959 was also upregulated in LPS-treated HGFs. Suppressed circ_0138959 increased cell viability and decreased pyroptosis of HGFs induced by LPS. miR-527 was a target of circ_0138959, and inhibition of miR-527 contributed to the dysfunction of LPS-treated HGFs and reversed the protective effects of downregulated circ_0138959. Additionally, miR-527 targeted CASP5. Increased CASP5 abrogated the effects of overexpressed miR-527 on cell viability and pyroptosis of LPS-treated HGFs. Inhibition of circ_0138959 promoted cell viability and suppressed pyroptosis of HGFs via the miR-527/CASP5 axis. Therefore, knockdown of circ_0138959 may be a promising therapy for periodontitis.

Association Between miR-143/145 rs4705343 Polymorphism and Risk of Congenital Heart Disease in a Chinese Tibetan Population

Objective: Congenital heart disease (CHD) is the most common birth defect worldwide and is caused by both genetic and environmental factors. The microRNA (miR)-143/145 cluster is involved in various biological processes related to cardiovascular development. The functional single nucleotide polymorphism (SNP) rs4705343 of miR-143/145 may influence the expression of these miRNAs. In this study, we aimed to estimate the association between miR-143/145 rs4705343 and the risk of CHD in a Chinese Tibetan population. Methods: Matrix-assisted laser desorption ionization time-of-flight mass spectrometry assays were performed to genotype the miRNA-143/145 rs4705343 SNP in 510 CHD Tibetan patients and 681 unrelated Tibetan healthy controls. The associations between the SNP frequencies and the CHD risk were analyzed by χ² test/Fisher's test and assessed by odds ratios (ORs) and 95% confidence intervals (95% CIs). Results: We successfully genotyped 1165 subjects with a SNP call rate of 97.8%. Under the allelic model we found that rs4705343 was not associated with the risk of CHD (p = 0.082), but under the recessive model the CC genotype at this locus was associated with a significantly increased risk of CHD compared with the other genotypes (CC vs TT+TC: OR = 1.60, 95% CI = 1.08-2.37, p = 0.017). Conclusion: The present study suggests that the rs4705343 CC genotype of miR-143/145 is associated with CHD risk in a Chinese Tibetan population.

Comparative analysis of circRNA expression profile and circRNA-miRNA-mRNA regulatory network between palmitic and stearic acid-induced lipotoxicity to pancreatic β cells

Chronic exposure to high concentrations of circulating palmitic acid and stearic acid leads to impaired β cell function, which accelerates the development of type 2 diabetes. However, differences in the mechanisms underlying this process between these two saturated fatty acids remain largely unknown. In this study, we screened for potential circular RNAs (circRNAs) and their associated regulatory pathways in palmitic acid- and stearic acid-induced mouse β-TC6 cell dysfunction. CircRNA high-throughput sequencing, gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes analysis were performed and co-expression and competing endogenous RNAs (ceRNA) networks were constructed. We identified that four circRNAs that were differentially expressed specifically in β cells exposed to palmitic acid, whereas four circRNAs were differentially expressed specifically in β cells exposed to stearic acid. Seven circRNAs were differentially co-expressed in palmitic acid- and stearic acid-treated β cells. In pathway exploration, we identified the core protein Solute carrier family 2 member 2 (SLc2a2), which is mainly involved in insulin resistance, maturity onset diabetes of the young and type 2 diabetes. The expressions of key circRNAs in β-TC6 cells were validated by Real time quantitative PCR, with a consistent result in high-throughput sequencing. The findings aid our understanding of the mechanisms governing the difference between palmitic acid- and stearic acid-induced β cell dysfunction and provide potential therapeutic targets for developing treatments against long-term high fat diet-induced β cell injury.

Abbreviations: Acvr1c: Activin A receptor, type 1C; CeRNA, Competing endogenous RNAs; circRNA, circular RNA; DEcircRNA: Differentially Expressed circular RNA; DEmiRNA: Differentially Expressed microRNA; DEmRNA: Differentially Expressed mRNA; GO: Gene Ontology; HPDHigh Palmitic acid Diet; HSD: High Stearic acid Diet; KEGG: Kyoto Encyclopedia of Genes and Genomes; miRNA: microRNA; ncRNAs: non-coding RNAs; qPCR: Real time quantitative PCRS; FAs: Saturated Fatty Acids; SLc2a2: Solute carrier family 2 member 2; T2D: Type 2 Diabetes

Circ_ROBO2/miR-149 Axis Promotes the Proliferation and Migration of Human Aortic Smooth Muscle Cells by Activating NF-κB Signaling

Atherosclerosis is the leading global cause of mortality. The occurrence of coronary artery disease (CAD) is regulated by a diversity of pathways, including circRNAs. However, the potential mechanisms of circRNAs in CAD remain unclear. Here, qRT-PCR was used to examine the expressions of miR-149 and circ_ROBO2. Their influences on cell proliferation, migration, and apoptosis were measured by CCK-8, trans-well, and flow cytometry assays, respectively. The protein levels of p-IκBα and NF-κB p65 were examined using western blot. The molecular interactions were validated using dual luciferase reporter and RNA pull-down assays. The expression patterns of circ_ROBO2 and miR-149 in CAD patients and PDGF-BB-treated human aortic smooth muscle cells (HASMCs) were upregulated and downregulated, respectively. Knockdown of circ_ROBO2 could markedly inhibit the capabilities of proliferation and migration, enhance the apoptotic rate, and suppress NF-κB signaling in PDGF-BB-treated HASMCs. Mechanistically, circ_ROBO2 acted as a sponge of miR-149 to activate TRAF6/NF-κB signaling. Rescue studies demonstrated that neither silencing miR-149 nor activation of NF-κB signaling obviously abolished the biological roles of circ_ROBO2 knockdown in PDGF-BB treated-HASMCs. This discovery elucidated a functional mechanism of circ_ROBO2 in CAD, suggesting that circRNAs serve a vital role in the progression of CAD.

Identification of circRNA_001846 as putative non-small cell lung cancer biomarker

CircRNAs play diverse roles in the regulation of oncogenic processes, yet the roles of these circRNAs in non-small cell lung cancer (NSCLC) remain to be fully clarified. Herein, patterns of circRNA expression in NSCLC tissues and paracancerous tissues were assessed, and the relationships between these circRNAs and NSCLC patient clinical findings were assessed. NSCLC tissues were evaluated using a circRNA microarray approach, with Quantitative real‑time polymerase chain reaction (qPCR) qPCR being used to validate candidate circRNA expression levels in NSCLC patients peripheral blood samples. GEO2R was used to analyze the array data. SPSS23.0, GraphPad Prism, and Sigmaplot were utilized for statistical analyses. Overall, 114 circRNAs that were differentially expressed in NSCLC tissue relative to paracancerous tissue levels were identified, of which 77 and 37 were downregulated and upregulated, respectively. CircRNA_001846 were then chosen based on its differential expression score. Consistent with array findings, serum samples from NSCLC patients exhibited circRNA_001846 upregulation relative to those from healthy individuals. The circRNA_001846 was associated with tumor differentiation, lymph node metastasis, and node metastasis stage. Receiver operating characteristic (ROC) curves analyses revealed that levels of circRNA_001846 in the serum were capable of differentiating between individuals diagnosed with NSCLC and controls at a cut off of 3.9496, yielding respective sensitivity and specificity values of 78.2% and 81.1%, with an area under the curve (AUC) value of 0.872. When combined with carcinoembryonic antigen (CEA), this circRNA achieved an improved AUC value of 0.925. CircRNA_001846 may represent a promising diagnostic biomarker for NSCLC.

Muscle Regeneration and RNA: New Perspectives for Ancient Molecules

The ability of the ribonucleic acid (RNA) to self-replicate, combined with a unique cocktail of chemical properties, suggested the existence of an RNA world at the origin of life. Nowadays, this hypothesis is supported by innovative high-throughput and biochemical approaches, which definitively revealed the essential contribution of RNA-mediated mechanisms to the regulation of fundamental processes of life. With the recent development of SARS-CoV-2 mRNA-based vaccines, the potential of RNA as a therapeutic tool has received public attention. Due to its intrinsic single-stranded nature and the ease with which it is synthesized in vitro, RNA indeed represents the most suitable tool for the development of drugs encompassing every type of human pathology. The maximum effectiveness and biochemical versatility is achieved in the guise of non-coding RNAs (ncRNAs), which are emerging as multifaceted regulators of tissue specification and homeostasis. Here, we report examples of coding and ncRNAs involved in muscle regeneration and discuss their potential as therapeutic tools. Small ncRNAs, such as miRNA and siRNA, have been successfully applied in the treatment of several diseases. The use of longer molecules, such as lncRNA and circRNA, is less advanced. However, based on the peculiar properties discussed below, they represent an innovative pool of RNA biomarkers and possible targets of clinical value.

Dysregulated Circulating Apoptosis- and Autophagy-Related lncRNAs as Diagnostic Markers in Coronary Artery Disease

Objective

Increasing evidence emphasizes the implications of dysregulated apoptosis and autophagy cellular processes in coronary artery disease (CAD). Herein, we aimed to explore apoptosis- and autophagy-related long noncoding RNAs (lncRNAs) in peripheral blood of CAD patients.

Methods

The mRNA and lncRNA expression profiles were retrieved from the Gene Expression Omnibus (GEO) database. With ∣fold change | >1.5 and adjusted p value < 0.05, differentially expressed apoptosis- and autophagy-related mRNAs were screened between CAD and healthy blood samples. Also, differentially expressed lncRNAs were identified for CAD. Using the psych package, apoptosis- and autophagy-related lncRNAs were defined with Spearson's correlation analysis. Receiver operating characteristic (ROC) curves were conducted for the assessment of the diagnosed efficacy of these apoptosis- and autophagy-related lncRNAs.

Results

Our results showed that 24 apoptosis- and autophagy-related mRNAs were abnormally expressed in CAD than normal controls. 12 circulating upregulated and 1 downregulated apoptosis- and autophagy-related lncRNAs were identified for CAD. The ROCs confirmed that AC004485.3 (AUC = 0.899), AC004920.3 (AUC = 0.93), AJ006998.2 (AUC = 0.776), H19 (AUC = 0.943), RP5-902P8.10 (AUC = 0.956), RP5-1114G22.2 (AUC = 0.883), RP11-247A12.1 (AUC = 0.885), RP11-288L9.4 (AUC = 0.928), RP11-344B5.2 (AUC = 0.858), RP11-452C8.1 (AUC = 0.929), RP11-565A3.1 (AUC = 0.893), and XXbac-B33L19.4 (AUC = 0.932) exhibited good performance in differentiating CAD from healthy controls.

Conclusion

Collectively, our findings proposed that circulating apoptosis- and autophagy-related lncRNAs could become underlying diagnostic markers for CAD in clinical practice.

Zinc finger C3H1 domain-containing protein (ZFC3H1) evaluates the prognosis and treatment of prostate adenocarcinoma (PRAD): A study based on TCGA data

The present study was aimed to evaluate the expression profile of Zinc finger C3H1 domain-containing protein (ZFC3H1) using bioinformatic analysis of public datasets from The Cancer Genome Atlas database (TCGA). The results showed that the expression levels of ZFC3H1 were notably lower than the corresponding non-cancerous tissues in prostate adenocarcinoma (PRAD), and patients in the high ZFC3H1-expression group showed poor survival. We hypothesized that the low expression of ZFC3H1 in tumor tissue might have be an inhibitory effect on the autoimmune system. We predicted the regulatory target and protein interaction partner network of ZFC3H1, and identified a PPI network composed of 26 node genes in PRAD. Furthermore, we found that the expression levels of MPHOSPH6 (encoding M-phase phosphoprotein 6) and MRPS31 (encoding mitochondrial ribosomal protein S31) were lower in PRAD tissues than in non-cancerous tissues, and the survival time of patients with high MPHOSPH6 and MRPS31 expression was poor. To further demonstrate the role of ZC3H1 in PRAD, we knocked-down the ZFC3H1 expression and found that the inhibition of ZFC3H1 significantly inhibited PRAD cell migration and invasion. Furthermore, ZFC3H1 siRNA treatment could reduce cell viability and increase the number of apoptotic cells in PRAD cells. Taken together, ZFC3H1 could represent a new marker for PRAD prognosis and provide a reference for the development of new therapies to treat PRAD.

miR-190a-3p Promotes Proliferation and Migration in Glioma Cells via YOD1

INTRODUCTION

To investigate the function of miR-190a-3p on the proliferation and migration of glioma.

METHODS

Twenty glioma samples and 6 normal brain tissue samples were collected. Normal human glial cell line HEB and glioma cell lines were used for the experiments. We then used TargetScan to predict the target genes of miR-190a-3p. Dual-luciferase reporter assay was also used to validate.

RESULTS

Combined with dual-luciferase reporter experiment, we finally verified that YOD1 was the aim, and it was low-expressed in glioma. Besides, a series of mechanism experiments then proved that miR-190a-3p negatively regulates YOD1 expression.

CONCLUSIONS

Our research was the first to demonstrate the promoting function of miR-190a-3p in the proliferation and migration of glioma and provided new views for the treatment of glioma. miR-190a-3p was expected to be a new target for molecular therapy of glioma.

CircRNA LRP6 promotes high-glucose induced proliferation and migration of vascular smooth muscle cells through regulating miR-545-3p/HMGA1 signaling axis

OBJECTIVE

The dysfunction of vascular smooth muscle cells (VSMCs) has been revealed to be closely linked with the pathogenesis of cardiovascular diseases in diabetes. Recently, circular RNAs (circRNAs) were found to regulate the behaviors of VSMCs. Here, we attempted to study the role of circLRP6 in VSMCs under diabetes condition.

METHODS

Human VSMCs were cultured under the condition of normal glucose (NG) or high glucose (HG). VSMC viability and proliferation were estimated by CCK-8 and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assays. VSMC migration and invasion were assessed via wound-healing and transwell experiments. Protein expression of HMGA1 was measured in VSMCs using western blot and immunofluorescence analysis. Relative expressions of circLRP6, miR-545-3p, and HMGA1 mRNA were estimated in VSMCs using qRT-PCR. The co-localization of circLRP6 and miR-545-3p was verified by fluorescence in situ hybridization (FISH) analysis. Binding sequence of miR-545-3p in circLRP6 or HMGA1 was predicted using StarBase tool, and verified by RNA immunoprecipitation and dual-luciferase reporter experiments.

RESULTS

HG exposure promoted VSMC proliferation, migration and invasion, upregulated the circLRP6 expression, and downregulated HMGA1 expression. Knockdown of circLRP6 or overexpression of miR-545-3p abrogated the HG-caused VSMC proliferation, migration and invasion. CircLRP6 severed as a miR-545-3p sponge, and HMGA1 was targeted by miR-545-3p. MiR-545-3p inhibitor blocked the suppressive effects of si-circLRP6 on VSMC in the presence of HG.

CONCLUSION

These findings suggest that circRNA LRP6 promotes HG-induced VSMC proliferation and migration through regulating miR-545-3p/HMGA1 signaling axis.

Knockdown of circ_0004104 Alleviates Oxidized Low-Density Lipoprotein-Induced Vascular Endothelial Cell Injury by Regulating miR-100/TNFAIP8 Axis

ABSTRACT

Coronary artery disease (CAD) is a common cardiovascular disease, mainly due to vascular endothelial cell (VEC) injury caused by atherosclerosis. Circular RNA has been shown to be involved in the regulation of various diseases. However, the role and mechanism of circ_0004104 in CAD are still unclear. Oxidized low-density lipoprotein (ox-LDL) was used to construct the VEC injury model in vitro. The expression levels of circ_0004104 and miR-100 were measured by quantitative real-time polymerase chain reaction. The proliferation of VECs was determined using 3-(45)-dimethylthiahiazo (-z-y1)-35-di-phenytetrazoliumromide assay and 5-ethynyl-2'-deoxyuridine staining assay. VEC apoptosis rate was assessed using flow cytometry, and caspase-3 activity was measured using a Caspase-3 Assay Kit. The protein expression levels of Ki-67, cleaved-caspase3, and tumor necrosis factor-α-induced protein 8 (TNFAIP8) were detected by western blot analysis. Furthermore, enzyme-linked immunosorbent assay was performed to assess the concentrations of inflammatory cytokines. In addition, the relationship between miR-100 and circ_0004104 or TNFAIP8 was confirmed by dual-luciferase reporter assay and biotin-labeled RNA pull-down assay. Our results revealed that circ_0004104 was upregulated and miR-100 was downregulated in patients with CAD and ox-LDL-induced VECs. Ox-LDL could inhibit the proliferation and promote the apoptosis and inflammation of VECs to induce VEC injury. However, silenced circ_0004104 could alleviate VEC injury induced by ox-LDL. Moreover, we found that circ_0004104 could sponge miR-100 and a miR-100 inhibitor could reverse the inhibition effect of circ_0004104 knockdown on ox-LDL-induced VEC injury. In addition, TNFAIP8 was a target of miR-100, and miR-100 alleviated ox-LDL-induced VEC injury by targeting TNFAIP8. Our data suggested that circ_0004104 promoted ox-LDL-induced VEC injury by the miR-100/TNFAIP8 axis, indicating that circ_0004104 might be a potential biomarker for CAD treatment.

Knockdown of circ_0003204 alleviates oxidative low-density lipoprotein-induced human umbilical vein endothelial cells injury: Circulating RNAs could explain atherosclerosis disease progression

Atherosclerosis (AS) is a serious cardiovascular disease. Circular RNAs (circRNAs) play an important role in the progression of many diseases, including AS. However, the role of circ_0003204 in AS is not clear. Oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs) were used to construct an AS cell model in vitro. Cell viability was assessed using cell counting kit 8 (CCK8) assay. Flow cytometry and caspase-3 activity were used to measure cell apoptosis. The contents of inflammatory cytokines were measured using enzyme-linked immunosorbent assay (ELISA). Oxidative stress marker expression and cell injury marker activity were detected by their corresponding Assay Kits. Besides, the expression levels of circ_0003204, miR-330-5p, and toll-like receptor 4 (TLR4) were tested by real-time polymerase chain reaction (qPCR). The interaction between miR-330-5p and circ_0003204 or TLR4 was examined by dual-luciferase reporter assay and RNA pull-down assay. Western blot (WB) analysis was used to determine the levels of TLR4 protein and nuclear factor-kappa B (NF-κB) signaling pathway-related protein. Our data suggested that ox-LDL could suppress viability and promote apoptosis, inflammatory response, and oxidative stress in HUVECs. circ_0003204 was highly expressed in ox-LDL-induced HUVECs, and its silencing could inhibit ox-LDL-induced HUVECs injury. miR-330-5p could be sponged by circ_0003204, and its inhibitor could reverse the inhibition effect of silenced circ_0003204 on ox-LDL-induced HUVECs injury. Further, TLR4 could be targeted by miR-330-5p, and its overexpression could invert the suppression effect of miR-330-5p on ox-LDL-induced HUVECs injury. The activity of the NF-κB signaling pathway was regulated by the circ_0003204/miR-330-5p/TLR4 axis. Our results indicated that circ_0003204 silencing could alleviate ox-LDL-induced HUVECs injury, suggesting that circ_0003204 might be a novel target for AS treatment.

The Emerging Role of Long Non-coding RNAs and Circular RNAs in Coronary Artery Disease

Coronary artery disease (CAD) is a common disorder caused by atherosclerotic processes in the coronary arteries. This condition results from abnormal interactions between numerous cell types in the artery walls. The main participating factors in this process are accumulation of lipid deposits, endothelial cell dysfunction, macrophage induction, and changes in smooth muscle cells. Several lines of evidence underscore participation of long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) in the pathogenesis of CAD. Several lncRNAs such as H19, ANRIL, MIAT, lnc-DC, IFNG-AS1, and LEF1-AS1 have been shown to be up-regulated in the biological materials obtained from CAD patients. On the other hand, Gas5, Chast, HULC, DICER1-AS1, and MEG3 have been down-regulated in CAD patients. Meanwhile, a number of circRNAs have been demonstrated to influence function of endothelial cells or vascular smooth muscle cells, thus contributing to the pathogenesis of CAD. In the current review, we summarize the function of lncRNAs and circRNAs in the development and progression of CAD.