RNA-Seq profiling of circular RNAs in mice with lipopolysaccharide-induced acute lung injury.

Acute lung injury (ALI) is a serious illness that develops suddenly, progresses rapidly, has a poor treatment response and a high mortality rate. Studies have found that circular RNAs (circRNA) play a critical role in several diseases, but their role in ALI remains unclear. The aim of this study was to identify circRNAs that are associated with ALI and investigate their potential molecular mechanisms. A comparison of lung circRNA and microRNA expression profiles in mice with ALI and controls was performed by RNA-sequencing. A bioinformatic analysis was conducted to identify differentially expressed (DE) RNAs, to construct competitive endogenous RNA (ceRNA) networks, and to analyze their function and pathways. Then, a protein-protein interaction (PPI) network was generated by the Search Tool for the Retrieval of Interacting Genes database, and hub genes were identified using Cytoscape. Furthermore, a key ceRNA subnetwork was constructed based on these hub genes. Overall, we found 239 DE circRNAs and 42 DE microRNAs in ALI mice compared to controls. Additionally, the molecular mechanism of ALI was further understood by building ceRNA networks based on these DE genes. ALI-induced circRNAs are mostly function in the inflammatory response and metabolic processes. Moreover, DE circRNAs are primarily involved in the nuclear factor (NF)-kappa B and PI3K-Akt signaling pathways. Seven hub genes were derived from the PPI network of 191 genes, followed by the construction of circRNA-miRNA-hub gene subnetworks. In this study, circRNA profiles are remarkably changed in mice with LPS-triggered ALI, and their potential contribution to the disease is revealed.

Differentially expressed circular RNA profiles and comprehensive analysis of circRNA-miRNA-mRNA regulatory network in microsatellite instability-high endometrial cancer.

The clinical benefit of anti-programmed cell death protein 1 (PD-1)-based immunotherapy among patients with microsatellite instable (MSI) endometrial cancer (EC) precedes that of microsatellite stable (MSS) EC, the mechanisms of which have not been fully understood. Circular RNAs (circRNAs) were reported to modulate immune evasion in several types of malignancies, while their roles in the immune regulation in EC remain largely unknown. Here, we conducted circRNA array analysis and mRNA-Sequencing of 10 MSI EC samples and 10 MSS EC samples and identified 1083 differentially expressed circRNAs (DE-circRNAs) and 864 differentially expressed mRNAs, based on which we constructed a circRNA-miRNA-mRNA comprehensive network consisting of 35 DE-circRNAs, 56 predicted miRNAs and 24 differentially expressed mRNAs. Finally, we confirmed hsa_circ_0058230 being positively correlated with CD8+ T cells infiltration, suggesting that it might take a part in anti-tumor immunity in EC.

Circulating exosomal circRNA-miRNA-mRNA network in a familial partial lipodystrophy type 3 family with a novel PPARG frameshift mutation c.418dup.

Familial partial lipodystrophy 3 (FPLD3) is a rare genetic disorder caused by loss-of-function mutations in the PPARG gene, characterized by a selective absence of subcutaneous fat and associated metabolic complications. However, the molecular mechanisms of FPLD3 remain unclear. In this study, we recruited a 17-yr-old Chinese female with FPLD3 and her family, identifying a novel PPARG frameshift mutation (exon 4: c.418dup: p.R140Kfs*7) that truncates the PPARγ protein at the seventh amino acid, significantly expanding the genetic landscape of FPLD3. By performing next-generation sequencing of circular RNAs (circRNAs), microRNAs (miRNAs), and mRNAs in plasma exosomes, we discovered 59 circRNAs, 57 miRNAs, and 299 mRNAs were significantly altered in the mutation carriers compared with the healthy controls. Integration analysis highlighted that the circ_0001597-miR-671-5p pair and 18 mRNAs might be incorporated into the metabolic regulatory networks of the FPLD3 induced by the novel PPARG mutation. Functional annotation suggested that these genes were significantly enriched in glucose- and lipid metabolism-related pathways. Among the circRNA-miRNA-mRNA network, we identified two critical regulators, early growth response-1 (EGR1), a key transcription factor known for its role in insulin signaling pathways and lipid metabolism, and 1-acylglycerol-3-phosphate O-acyltransferase 3 (AGPAT3), which gets involved in the biosynthesis of triglycerides and lipolysis. Circ_0001597 regulates the expression of these genes through miR-671-5p, potentially contributing to the pathophysiology of FPLD3. Overall, this study clarified a circulating exosomal circRNA-miRNA-mRNA network in a FPLD3 family with a novel PPARG mutation, providing evidence for exploring promising biomarkers and developing novel therapeutic strategies for this rare genetic disorder.NEW & NOTEWORTHY Through the establishment of a ceRNA regulatory networks in a novel PPARG frameshift mutation c.418dup-induced FPLD3 pedigree, this study reveals that circ_0001597 may contribute to the pathophysiology of FPLD3 by sequestering miR-671-5p to regulate the expression of EGR1 and AGPAT3, pivotal genes situated in the triglyceride (TG) synthesis and lipolysis pathways. Current findings expand our molecular understanding of adipose tissue dysfunction, providing potential blood biomarkers and therapeutic avenues for lipodystrophy and associated metabolic complications.

Comprehensive analysis of the miRNA-mRNA regulatory network involved in spontaneous recovery of an H2O2-induced zebrafish cataract model.

OBJECTIVE: To identify the hub miRNAs and mRNAs contributing to the spontaneous recovery of an H2O2-induced zebrafish cataract model. METHODS: Zebrafishes were divided into three groups, i.e., Group A, which included normal control fish (day 0), and Groups B and C, where fish were injected with 2.5% hydrogen peroxide into the anterior chamber and reared for 14 and 30 days, respectively. Fish eyes were examined by stereomicroscope photography and optical coherence tomography (OCT). RNA profiles of fish lenses were detected by RNA sequencing. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEmiRs) were identified among three groups. The DEGs and DEmiRs, which changed in opposite positions between "B vs. A" and "C vs. B" were defined as ODGs (opposite positions changed DEGs) and ODmiRs (opposite positions changed DEmiRs). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) analysis were carried out by R language. The protein-protein interaction network (PPI) was constructed using STRING. Potential targets of miRNAs were obtained using miRanda. miRNA-mRNA networks were constructed by Cytoscape. RESULTS: The fish lens opacity formed on day 14 and recovered to transparent on day 30 after injection. Compared to group B, 1366 DEGs and 54 DEmiRs were identified in group C. "C vs. B" DEGs were enriched in gene clusters related to development and oxidative phosphorylation. Target genes of DEmiRs were enriched in clusters such as development and cysteine metabolism. Among three groups, 786 ODGs and 27 ODmiRs were identified, and 480 ODGs were predicted as targets of ODmiRs. Target ODGs were enriched in pathways related to methionine metabolism, ubiquitin, sensory system development, and structural constituents of the eye lens. In addition, we established an ODmiRs-ODGs regulation network. CONCLUSION: We identified several hub mRNAs and altered miRNAs in the formation and reversal of zebrafish cataracts. These hub miRNAs/mRNAs could be potential targets for the non-surgical treatment of ARC.

Identification of Novel Prognostic Long Non-coding RNAs in Lung Adenocarcinoma Using WGCNA Analysis.

Long non-coding RNAs play crucial role in the tumorigenesis of lung adenocarcinoma (LUAD). However, the function of a large number of lncRNAs in LUAD has not been investigated yet. Weighted gene correlation network analysis (WGCNA) was applied to construct the co-expression module in the TCGA-LUAD cohort. Protein-protein interaction (PPI) network was used to explore the relationship of genes in the key module. The function of the key module on the prognosis in LUAD was analyzed using GO and KEGG analysis. Finally, we constructed the mRNA-lncRNA co-expression network in the key module to identify the hub lncRNAs that play crucial role in the prognosis in LUAD. The most highly expressed 2500 mRNAs and 2500 lncRNAs in the TCGA-LUAD cohort were clustered into 21 modules. After analyzing the correlation between the module and prognostic clinical traits, the Tan module, consisting of 130 genes, was selected as the key module on the prognosis in LUAD. And then, we found that genes in the key module were majorly enriched in ten multiple signaling pathways. Subsequently, we constructed the mRNA-lncRNA co-expression network based on the genes in the key module. Finally, we identified three lncRNAs and nineteen mRNAs that could be the promising prognostic biomarkers for LUAD. We identified three lncRNAs (MIR99AHG, ADAMTS9-AS2, and AC037459.2) and nineteen mRNAs as potential prognostic biomarkers in LUAD, which provided new insight for prognosis monitoring and therapy development in LUAD.

Comparative transcriptomics combined with physiological and functional analysis reveals the regulatory mechanism of rainbow trout (Oncorhynchus mykiss) under acute hypoxia stress.

Hypoxia, largely triggered by global warming and water contamination, has become an environmental issue of great concern, posing a great threat to aquatic ecosystem. As one of the world's most economically important fish, rainbow trout (Oncorhynchus mykiss) is extremely intolerant of hypoxic environments, however, little is known about the roles of non-coding RNAs (ncRNAs) in the response of rainbow trout to hypoxia stress. Herein, effects of moderate (Tm12L) and severe hypoxia for 12 h (Ts12L) and 12 h reoxygenation on histology, biochemical parameters (antioxidant, metabolism and immunity) and transcriptome (lncRNA, miRNA and mRNA) in rainbow trout liver were investigated. We further validated the regulatory relationships between LOC110519952, novel-m0023-5p and glut1a via dual­luciferase reporter, overexpression and silencing assays. Compared with Tm12L, the liver in Ts12L showed more severe oxidative damage. Anaerobic, lipid and protein metabolism was enhanced under hypoxia stress, especially in Ts12L. We also found that Tm12L could strengthen innate immune response, which was inhibited in Ts12L. Besides, several hypoxia-related genes (glut1a, vegfaa, hmox, epoa, foxo1a and igfbp1) and ceRNA networks were identified from 1824, 427 and 545 differentially expressed mRNAs, miRNAs and lncRNAs, including LOC118965299-novel-m0179-3p-epoa, LOC110519952-novel-m0023-5p-glut1a, MSTRG.7382.2-miR-184-y-hmox and LOC110520012-miR-206-y-vegfaa. Through in vitro and in vivo functional analysis, we demonstrated that glut1a is a target of novel-m0023-5p, and LOC110519952 can positively regulate glut1a by targeting novel-m0023-5p. Introduction of LOC110519952 could attenuate the promoting effects of novel-m0023-5p on rainbow trout liver cell viability and proliferation. This study highlights the differences in the regulatory mechanism of rainbow trout under different concentrations of hypoxia stress and provides valuable data for further research on the molecular mechanisms of fish adaptation to hypoxic environments.

Mesenchymal stem cell-regulated miRNA-mRNA landscape in acute-on-chronic liver failure.

BACKGROUND: Acute-on-chronic liver failure (ACLF) is a major challenge in the field of hepatology. While mesenchymal stem cell (MSC) therapy can improve the prognosis of patients with ACLF, the molecular mechanisms through which MSCs attenuate ACLF remain poorly understood. We performed global miRNA and mRNA expression profiling via next-generation sequencing of liver tissues from MSC-treated ACLF mice to identify important signaling pathways and major factors implicated in ACLF alleviation by MSCs. METHODS: Carbon tetrachloride-induced ACLF mice were treated with saline or mouse bone marrow-derived MSCs. Mouse livers were subjected to miRNA and mRNA sequencing. Related signal transduction pathways were obtained through Gene Set Enrichment Analysis. Functional enrichment, protein-protein interaction, and immune infiltration analyses were performed for the differentially expressed miRNA target genes (DETs). Hub miRNA and mRNA associated with liver injury were analyzed using LASSO regression. The expression levels of hub genes were subjected to Pearson's correlation analysis and verified using RT-qPCR. The biological functions of hub genes were verified in vitro. RESULTS: The tricarboxylic acid cycle and peroxisome proliferator-activated receptor pathways were activated in the MSC-treated groups. The proportions of liver-infiltrating NK resting cells, M2 macrophages, follicular helper T cells, and other immune cells were altered after MSC treatment. The expression levels of six miRNAs and 10 transcripts correlated with the degree of liver injury. miR-27a-5p was downregulated in the mouse liver after MSC treatment, while its target gene E2f2 was upregulated. miR-27a-5p inhibited E2F2 expression, suppressed G1/S phase transition and proliferation of hepatocytes, in addition to promoting their apoptosis. CONCLUSIONS: This is the first comprehensive analysis of miRNA and mRNA expression in the liver tissue of ACLF mice after MSC treatment. The results revealed global changes in hepatic pathways and immune subpopulations. The miR-27a-5p/E2F2 axis emerged as a central regulator of the MSC-induced attenuation of ACLF. The current findings improve our understanding of the molecular mechanisms through which MSCs alleviate ACLF.

Uncovering potential diagnostic biomarkers of acute myocardial infarction based on machine learning and analyzing its relationship with immune cells.

BACKGROUND: Acute myocardial infarction (AMI) is a common cardiovascular disease. This study aimed to mine biomarkers associated with AMI to aid in clinical diagnosis and management. METHODS: All mRNA and miRNA data were downloaded from public database. Differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) were identified using the metaMA and limma packages, respectively. Functional analysis of the DEmRNAs was performed. In order to explore the relationship between miRNA and mRNA, we construct miRNA-mRNA negative regulatory network. Potential biomarkers were identified based on machine learning. Subsequently, ROC and immune correlation analysis were performed on the identified key DEmRNA biomarkers. RESULTS: According to the false discovery rate < 0.05, 92 DEmRNAs and 272 DEmiRNAs were identified. GSEA analysis found that kegg_peroxisome was up-regulated in AMI and kegg_steroid_hormone_biosynthesis was down-regulated in AMI compared to normal controls. 5 key DEmRNA biomarkers were identified based on machine learning, and classification diagnostic models were constructed. The random forests (RF) model has the highest accuracy. This indicates that RF model has high diagnostic value and may contribute to the early diagnosis of AMI. ROC analysis found that the area under curve of 5 key DEmRNA biomarkers were all greater than 0.7. Pearson correlation analysis showed that 5 key DEmRNA biomarkers were correlated with most of the differential infiltrating immune cells. CONCLUSION: The identification of new molecular biomarkers provides potential research directions for exploring the molecular mechanism of AMI. Furthermore, it is important to explore new diagnostic genetic biomarkers for the diagnosis and treatment of AMI.

Identification and validation of a novel four-gene diagnostic model for neonatal early-onset sepsis with bacterial infection.

Neonatal early-onset sepsis (EOS) has unfortunately been the third leading cause of neonatal death worldwide. The current study is aimed at discovering reliable biomarkers for the diagnosis of neonatal EOS through transcriptomic analysis of publicly available datasets. Whole blood mRNA expression profiling of neonatal EOS patients in the GSE25504 dataset was downloaded and analyzed. The binomial LASSO model was constructed to select genes that most accurately predicted neonatal EOS. Then, ROC curves were generated to assess the performance of the predictive features in differentiating between neonatal EOS and normal infants. Finally, the miRNA-mRNA network was established to explore the potential biological mechanisms of genes within the model. Four genes (CST7, CD3G, CD247, and ANKRD22) were identified that most accurately predicted neonatal EOS and were subsequently used to construct a diagnostic model. ROC analysis revealed that this diagnostic model performed well in differentiating between neonatal EOS and normal infants in both the GSE25504 dataset and our clinical cohort. Finally, the miRNA-mRNA network consisting of the four genes and potential target miRNAs was constructed. Through bioinformatics analysis, a diagnostic four-gene model that can accurately distinguish neonatal EOS in newborns with bacterial infection was constructed, which can be used as an auxiliary test for diagnosing neonatal EOS with bacterial infection in the future. CONCLUSION: In the current study, we analyzed gene expression profiles of neonatal EOS patients from public databases to develop a genetic model for predicting sepsis, which could provide insight into early molecular changes and biological mechanisms of neonatal EOS. WHAT IS KNOWN: • Infants with suspected EOS usually receive empiric antibiotic therapy directly after birth. • When blood cultures are negative after 48 to 72 hours, empirical antibiotic treatment is often halted. Needless to say, this is not a short time. Additionally, because of the concern for inadequate clinical sepsis production and the limited sensitivity of blood cultures, the duration of antibiotic therapy for the kid is typically extended. WHAT IS NEW: • We established a 4-gene diagnostic model of neonatal EOS with bacterial infection by bioinformatics analysis method. The model has better diagnostic performance compared with conventional inflammatory indicators such as CRP, Hb, NEU%, and PCT.

Lipid metabolism-related miRNAs with potential diagnostic roles in prostate cancer.

BACKGROUND: Prostate cancer (PCa), the second most prevalent solid tumor among men worldwide, has caused greatly increasing mortality in PCa patients. The effects of lipid metabolism on tumor growth have been explored, but the mechanistic details of the association of lipid metabolism disorders with PCa remain largely elusive. METHODS: The RNA sequencing data of the GSE45604 and The Cancer Genome Atlas-Prostate Adenocarcinoma (TCGA-PRAD) datasets were extracted from the Gene Expression Omnibus (GEO) and UCSC Xena databases, respectively. The Molecular Signatures Database (MSigDB) was utilized to identify lipid metabolism-related genes. The limma R package was used to identify differentially expressed lipid metabolism-related genes (DE-LMRGs) and differentially expressed microRNAs (DEMs). Moreover, least absolute shrinkage and selection operator (LASSO), extreme gradient boosting (XGBoost), and support vector machine-recursive feature elimination (SVM-RFE) were applied to select signature miRNAs and construct a lipid metabolism-related diagnostic model. The expression levels of selected differentially expressed lipid metabolism-related miRNAs (DE-LMRMs) in PCa and benign prostate hyperplasia (BPH) specimens were verified using quantitative real-time polymerase chain reaction (qRT‒PCR). Furthermore, a transcription factor (TF)-miRNA‒mRNA network was constructed. Eventually, Kaplan‒Meier (KM) curves were plotted to illustrate the associations between signature miRNA-related mRNAs and TFs and overall survival (OS) along with biochemical recurrence-free survival (BCR). RESULTS: Forty-seven LMRMs were screened based on the correlation analysis of 29 DE-LMRGs and 56 DEMs, in which 27 LMRMs were stably expressed in the GSE45604 dataset. Subsequently, receiver operating characteristic (ROC) curves and machine learning methods were employed to develop a lipid metabolism-related diagnostic signature, which may be of diagnostic value for PCa patients. qRT‒PCR results showed that all seven key DE-LMRMs were differentially expressed between PCa and BPH tissues. Eventually, a TF-miRNA‒mRNA network was constructed. CONCLUSIONS: These results suggested that 7 key diagnostic miRNAs were closely related to PCa pathological processes and provided new targets for the diagnosis and treatment of PCa. Moreover, CLIC6 and SCNN1A linked to miR-200c-3p had good prognostic potential and provided valuable insights into the pathogenesis of PCa.

Profiling and Bioinformatics Analyses of Hypoxia-Induced Differential Expression of Long Non-coding RNA in Glioblastoma Multiforme Cells.

Hypoxic microenvironments are intricately linked to malignant characteristics of glioblastoma multiforme (GBM). Long non-coding ribonucleic acids (lncRNAs) have been reported to be involved in the progression of GBM and closely associated with hypoxia. Nevertheless, the differential expression profiles as well as functional roles of lncRNAs in GBM cells under hypoxic conditions remain largely obscure. We explored the expression profiles of lncRNAs in hypoxic U87 cells as well as T98G cells using sequencing analysis. The effect of differentially expressed lncRNAs (DElncRNAs) was assessed through bioinformatic analysis. Furthermore, the expression of lncRNAs significantly dysregulated in both U87 and T98G cells was further validated using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Relevant cell functional experiments were also conducted. We used predicted RNA-binding proteins (RBPs) to construct an interaction network via the interaction prediction module. U87 and T98G cells showed dysregulation of 1115 and 597 lncRNAs, respectively. Gene Ontology (GO) analysis indicated that altered lncRNA expression was associated with nucleotide-excision repair and cell metabolism in GBM cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed the association between dysregulated lncRNAs and the Hippo signaling pathway under hypoxia. The dysregulation of six selected lncRNAs (ENST00000371192, uc003tnq.3, ENST00000262952, ENST00000609350, ENST00000610036, and NR_046262) was validated by qRT-PCR. Investigation of lncRNA-microRNA (miRNA)-mRNA networks centered on HIF-1α demonstrated cross-talk between the six validated lncRNAs and 16 related miRNAs. Functional experiments showed the significant inhibition of GBM cell proliferation, invasion, and migration by the knockdown of uc003tnq.3 in vitro. Additionally, uc003tnq.3 was used to construct a comprehensive RBP-transcription factor (TF)-miRNA interaction network. The expression of LncRNAs was dysregulated in GBM cells under hypoxic conditions. The identified six lncRNAs might exert important effect on the development of GBM under hypoxic microenvironment.

Profiling and integrated analysis of differentially expressed circRNAs in cervical cancer.

Circular RNAs (circRNAs) are a new type of regulatory RNAs, which have been identified to play critical role in various tumors. However, the profiles and roles of circRNAs in cervical cancer (CCa) have not been fully understood and need to be further explored. In the present study, we performed circRNA array and mRNA-sequencing (mRNA-Seq) to profile the differentially expressed circRNAs and mRNAs in CCa tissues. A total of 397 differentially expressed circRNAs and 2138 differentially expressed mRNAs were detected, respectively. Subsequently, a circRNA-miRNA-mRNA regulatory network was constructed and indicated that hsa_circ_0026377 was downregulated in CCa. Overexpression of hsa_circ_0026377 inhibited HeLa and SiHa cells proliferation, migration and invasion. Collectively, this study provided new insights into the circRNA profiles in CCa and suggested that hsa_circ_0026377 might play important roles in CCa development.

Targeting HIF1-alpha/miR-326/ITGA5 axis potentiates chemotherapy response in triple-negative breast cancer.

PURPOSE: Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer that is frequently treated with chemotherapy. However, many patients exhibit either de novo chemoresistance or ultimately develop resistance to chemotherapy, leading to significantly high mortality rates. Therefore, increasing the efficacy of chemotherapy has potential to improve patient outcomes. METHODS: Here, we performed whole transcriptome sequencing (both RNA and small RNA-sequencing), coupled with network simulations and patient survival data analyses to build a novel miRNA-mRNA interaction network governing chemoresistance in TNBC. We performed cell proliferation assay, Western blotting, RNAi/miRNA mimic experiments, FN coating, 3D cultures, and ChIP assays to validate the interactions in the network, and their functional roles in chemoresistance. We developed xenograft models to test the therapeutic potential of the identified key miRNA/proteins in potentiating chemoresponse in vivo. We also analyzed several patient datasets to evaluate the clinical relevance of our findings. RESULTS: We identified fibronectin (FN1) as a central chemoresistance driver gene. Overexpressing miR-326 reversed FN1-driven chemoresistance by targeting FN1 receptor, ITGA5. miR-326 was downregulated by increased hypoxia/HIF1A and ECM stiffness in chemoresistant tumors, leading to upregulation of ITGA5 and activation of the downstream FAK/Src signaling pathways. Overexpression of miR-326 or inhibition of ITGA5 overcame FN1-driven chemotherapy resistance in vitro by inhibiting FAK/Src pathway and potentiated the efficacy of chemotherapy in vivo. Importantly, lower expression of miR-326 or higher levels of predicted miR-326 target genes was significantly associated with worse overall survival in chemotherapy-treated TNBC patients. CONCLUSION: FN1 is central in chemoresistance. In chemoresistant tumors, hypoxia and resulting ECM stiffness repress the expression of the tumor suppressor miRNA, miR-326. Hence, re-expression of miR-326 or inhibition of its target ITGA5 reverses FN1-driven chemoresistance making them attractive therapeutic approaches to enhance chemotherapy response in TNBCs.

A regulatory miRNA-mRNA network is associated with transplantation response in acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) is a life-threatening complication characterized by rapid decline in renal function, which frequently occurs after transplantation surgery. However, the molecular mechanism underlying the development of post-transplant (post-Tx) AKI still remains unknown. An increasing number of studies have demonstrated that certain microRNAs (miRNAs) exert crucial functions in AKI. The present study sought to elucidate the molecular mechanisms in post-Tx AKI by constructing a regulatory miRNA-mRNA network. RESULTS: Based on two datasets (GSE53771 and GSE53769), three key modules, which contained 55 mRNAs, 76 mRNAs, and 151 miRNAs, were identified by performing weighted gene co-expression network analysis (WGCNA). The miRDIP v4.1 was applied to predict the interactions of key module mRNAs and miRNAs, and the miRNA-mRNA pairs with confidence of more than 0.2 were selected to construct a regulatory miRNA-mRNA network by Cytoscape. The miRNA-mRNA network consisted of 82 nodes (48 mRNAs and 34 miRNAs) and 125 edges. Two miRNAs (miR-203a-3p and miR-205-5p) and ERBB4 with higher node degrees compared with other nodes might play a central role in post-Tx AKI. Additionally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that this network was mainly involved in kidney-/renal-related functions and PI3K-Akt/HIF-1/Ras/MAPK signaling pathways. CONCLUSION: We constructed a regulatory miRNA-mRNA network to provide novel insights into post-Tx AKI development, which might help discover new biomarkers or therapeutic drugs for enhancing the ability for early prediction and intervention and decreasing mortality rate of AKI after transplantation.

Hsa-miR-3202 attenuates Jurkat cell infiltration via MMP2 in primary Sjögren's syndrome.

BACKGROUND: Primary Sjögren's syndrome is characterized by lymphocytic infiltration and dysfunction of exocrine glands. The persistent presence of lymphocytes in these glands is an important cause of injury to glandular epithelial cells. MicroRNAs play an important role in primary Sjögren's syndrome and regulate mRNA expression. This study evaluated the expression of microRNA related to lymphocyte infiltration in primary Sjögren's syndrome patients so as to find novel diagnostic and therapeutic targets for primary Sjögren's syndrome. We also explored the microRNA-mRNA networks related to lymphocyte infiltration. METHODS: mRNA-seq and microRNA-seq of peripheral blood mononuclear cells (PBMCs) were performed on samples from five primary Sjögren's syndrome patients and five matched healthy controls. Meanwhile, microRNA-mRNA network analysis was also conducted. RT-qPCR was used for validation of differentially expressed RNAs. Immunohistochemistry analysis was used to detect MMP2 expression in labial gland tissue. Hsa-miR-3202 mimics/inhibitor-transfected Jurkat cells were used to measure the effects of hsa-miR-3202 on the infiltration potential of T cells. RESULTS: mRNA and microRNA sequencing revealed that 84 differentially expressed mRNAs and 49 differentially expressed microRNAs had a mutual regulatory relationship. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that differentially expressed MMP2 and its related microRNA, hsa-miR-3202, were enriched in the leukocyte transendothelial migration pathway. MMP2 was highly expressed in PBMC and labial gland tissue in primary Sjögren's syndrome patients. Hsa-miR-3202 was lower expressed in primary Sjögren's syndrome than healthy control. Furthermore, hsa-miR-3202 mimics transfection decreased MMP2 expression in Jurkat cells, and inhibited Jurkat cells invasion (p = 0.047). CONCLUSION: Large number of differentially expressed microRNAs and mRNAs were detected in primary Sjögren's syndrome, and these differentially expressed microRNAs and mRNAs had a mutual regulatory relationship and played an important role in primary Sjögren's syndrome. In the study, we found hsa-miR-3202 regulate MMP2 and inhibited the infiltration of T cells from peripheral blood into the gland, which played a protective role.

Identification of pivotal microRNAs involved in the development and progression of salivary adenoid cystic carcinoma.

BACKGROUND: miRNAs and mRNAs have been significantly implicated in tumorigenesis and served as promising prognostic biomarkers for human cancer. Hence, this study was aimed to develop the pivotal miRNA biomarkers-based prognostic signature for salivary adenoid cystic carcinoma. METHODS: The miRNA and mRNA expression data were integrated from the gene expression omnibus database to study their involvement in salivary adenoid cystic carcinoma development and progression. Gene ontology and kyoto encyclopedia of genes and genomes were conducted to analyze the biological pathways. Reverse transcription-quantitative PCR was used to verify the expression of selected miRNAs in salivary adenoid cystic carcinoma and corresponding normal tissues. RESULTS: There were 386 differentially expressed genes: 158 upregulated and 228 downregulated genes and 102 differentially expressed miRNAs: 78 upregulated and 24 downregulated miRNAs in the salivary adenoid cystic carcinoma samples. A miRNA-mRNA network containing 11 miRNAs and 199 genes was subsequently constructed. Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis revealed that the genes targeted by the 11 miRNAs were mostly involved in tumor-related pathways and processes, such as miRNAs in cancer, focal adhesion, neurotrophin signaling pathway, and the PI3K-Akt signaling pathway. Among them, 4 miRNAs (miR-375, miR-494, miR-34c-5p, and miR-331-3p) were selected to verify by reverse transcription-quantitative PCR in 36 pairs of collected salivary adenoid cystic carcinoma and adjacent nontumor samples. Overall survival analysis revealed that the higher expression of miR-331-3p was significantly associated with a worst overall survival and multivariate Cox regression analysis suggested that hsa-miR-331-3p could be an independent prognostic factor for salivary adenoid cystic carcinoma. CONCLUSION: Our results revealed that 4-miRNAs signature was a powerful prognostic biomarker for salivary adenoid cystic carcinoma, which provide a basis for exploring deeper mechanisms regarding the progression of salivary adenoid cystic carcinoma, and leading to the development of potential therapeutic strategies.

Transcriptome of miRNA during inhibition of Bombyx mori nuclear polyhedrosis virus by geldanamycin in BmN cells.

Bombyx mori nuclear polyhedrosis virus (BmNPV) is one of several viruses that cause great harm to the sericulture industry, and its pathogenic mechanism is still being explored. Geldanamycin (GA), a kind of HSP90 inhibitor, has been verified to suppress BmNPV proliferation. However, the molecular mechanism by which GA inhibits BmNPV is unclear. MicroRNAs (miRNAs) have been shown to play a key role in regulating virus proliferation and host-pathogen interactions. In this study, BmN cells infected with BmNPV were treated by GA and DMSO for 72 h, respectively, then transcriptome analysis of miRNA was performed from the GA group and the control group. As a result, a total of 29 miRNAs were differentially expressed (DE), with 13 upregulated and 16 downregulated. Using bioinformatics analysis, it was found that the target genes of DEmiRNAs were involved in ubiquitin-mediated proteolysis, phagosome, proteasome, endocytosis pathways, and so on. Six DEmiRNAs were verified by quantitative reverse-transcription polymerase chain reaction. DElong noncoding RNA (DElncRNA)-DEmiRNA-messenger RNA (mRNA) regulatory networks involved in apoptosis and immune pathways were constructed in GA-treated BmN cells, which included 12 DEmiRNA, 132 DElncRNA, and 69 mRNAs. This regulatory network enriched the functional role of miRNA in the BmNPV-silkworm interactions and improved our understanding of the molecular mechanism of HSP90 inhibitors on BmNPV proliferation.

Machine Learning Using Gene-Sets to Infer miRNA Function.

miRNA are regulators of cell phenotype, and there is clear evidence that these small posttranscriptional modifiers of gene expression are involved in defining a cellular response across states of development and disease. Classical methods for elucidating the repressive effect of a miRNA on its targets involve controlling for the many factors influencing miRNA action, and this can be achieved in cell lines, but misses tissue and organism level context which are key to a miRNA function. Also, current technology to carry out this validation is limited in both generalizability and throughput. Methodologies with greater scalability and rapidity are required to better understand the function of these important species of RNA. To this end, there is an increasing store of RNA expression level data incorporating both miRNA and mRNA, and in this chapter, we describe how to use machine learning and gene-sets to translate the knowledge of phenotype defined by mRNA to putative roles for miRNA. We outline our approach to this process and highlight how it was done for our miRNA annotation of the hallmarks of cancer using the Cancer Genome Atlas (TCGA) dataset. The concepts we present are applicable across datasets and phenotypes, and we highlight potential pitfalls and challenges that may be faced as they are used.

An integrated in silico analysis highlighted angiogenesis regulating miRNA-mRNA network in PCOS pathophysiology.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a heterogeneous endocrinopathy and a leading cause of anovulatory infertility. Angiogenesis is vital for ovarian folliculogenesis. The expression of angiogenesis-associated genes/proteins is altered in the ovary of PCOS women. However, information on microRNAs (miRNAs) regulating their expression is limited. This study aims to identify dysregulated angiogenesis-related genes in the ovary of women with PCOS, to identify miRNAs regulating them, and to construct a miRNA-mRNA network associated with angiogenesis. METHODS: A comprehensive literature search and reanalysis of seven ovarian GEO microarray datasets were performed to identify differentially expressed angiogenesis-related genes in PCOS. These target genes were used to predict their regulating miRNAs by querying miRNA databases and their expression in the ovary was verified. Panther and STRING database were used for functional enrichment. Gene expression of shortlisted miRNAs was studied in granulosa cells using digital droplet PCR. RESULTS: The miRNAs expressed in the ovary and potentially targeting dysregulated angiogenesis-related genes in PCOS were identified and those enriched in angiogenesis-related pathways, like VEGF, FGF, PI3K/Akt, Notch signaling, and ECM interaction were shortlisted. Analysis showed PI3K/Akt signaling was the most enriched pathway. MiR-218-5p, miR-214-3p, miR-20a-5p, and miR-140-3p associated with the PI3K/Akt pathway were found to be up-regulated in granulosa cells of women with PCOS. CONCLUSIONS: By in silico analysis, we identified crucial dysregulated angiogenesis-related genes, the miRNA-mRNA interactions, and signaling pathways involved in impaired follicular angiogenesis in PCOS. This work provides a novel insight into the mechanism of aberrant ovarian angiogenesis contributing to PCOS pathophysiology.

Aberrant methylation modifications reflect specific drug responses in small cell lung cancer.

In the study, Methylated DNA immunoprecipitation sequencing, RNA sequencing, and whole-exome sequencing were employed to clinical small cell lung cancer (SCLC) patients. Then, we verified the therapeutic predictive effects of differentially methylated genes (DMGs) in 62 SCLC cell lines. Of 4552 DMGs between chemo-sensitive and chemo-insensitive group, coding genes constituted the largest percentage (85.08%), followed by lncRNAs (10.52%) and miRNAs (3.56%). Both two groups demonstrated two methylation peaks near transcription start site and transcription end site. Two lncRNA-miRNA-mRNA networks suggested the extensive genome connection between chemotherapy efficacy-related non-coding RNAs (ncRNAs) and mRNAs. Combing miRNAs and lncRNAs could effectively predict chemotherapy response in SCLC. In addition, we also verified the predictive values of mutated genes in SCLC cell lines. This study was the first to evaluate multiple drugs efficacy-related ncRNAs and mRNAs which were modified by methylation in SCLC. DMGs identified in our research might serve as promising therapeutic targets to reverse drugs-insensitivity by complex lncRNA-miRNA-mRNA mechanisms in SCLC.