Deregulated microRNAs in CD4+ T cells from individuals with latent tuberculosis versus active tuberculosis

The mechanisms of latent tuberculosis (TB) infection remain elusive. Roles of microRNA (miRNA) have been highlighted in pathogen–host interactions recently. To identify miRNAs involved in the immune response to TB, expression profiles of miRNAs in CD4⁺ T cells from patients with latent TB, active TB and healthy controls were investigated by microarray assay and validated by RT‐qPCR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were used to analyse the significant functions and involvement in signalling pathways of the differentially expressed miRNAs. To identify potential target genes for miR‐29, interferon‐γ (IFN‐γ) mRNA expression was measured by RT‐qPCR. Our results showed that 27 miRNAs were deregulated among the three groups. RT‐qPCR results were generally consistent with the microarray data. We observed an inverse correlation between miR‐29 level and IFN‐γ mRNA expression in CD4⁺ T cells. GO and KEGG pathway analysis showed that the possible target genes of deregulated miRNAs were significantly enriched in mitogen‐activated protein kinase signalling pathway, focal adhesion and extracellular matrix receptor interaction, which might be involved in the transition from latent to active TB. In all, for the first time, our study revealed that some miRNAs in CD4⁺ T cells were altered in latent and active TB. Function and pathway analysis highlighted the possible involvement of miRNA‐deregulated mRNAs in TB. The study might help to improve understanding of the relationship between miRNAs in CD4⁺ T cells and TB, and laid an important foundation for further identification of the underlying mechanisms of latent TB infection and its reactivation.     

hsa_circRNA_100533 regulates GNAS by sponging hsa_miR_933 to prevent oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor of the head and neck region. Circular RNA (circRNA), as one kind of noncoding RNA, involves in biological processes in diverse cancers. circRNA functions mainly as the microRNA (miRNA) sponge, competitively binding to miRNAs to regulate target gene expressions. However, the expression profiles and roles of circRNAs in OSCC are still unexplored. circRNA microarrays and quantitative real-time polymerase chain reaction was used to identify the hsa_circRNA_100533 downregulated in OSCC tissues and cell lines. Bioinformatics methods were used to predict the interactions among circRNAs, miRNA, and target genes. Based on the luciferase reporter assay and AGO2 RIP assay, we found that hsa_circRNA_100533 binds to miRNAs as a miRNA sponge. hsa_circRNA_100533 inhibited cell proliferation, migration, and promoted cell apoptosis in OSCC cell lines, which could be blocked by hsa-miR-933 overexpression. hsa_circRNA_100533 binds to hsa-miR-933 as a miRNA sponge to regulate GNAS expression, and to modulate cell proliferation, migration, and apoptosis. In summary, the hsa_circRNA_100533-miR-933-GNAS axis affect the proliferation and apoptosis of OSCC cells through the mechanism of competing endogenous RNAs. hsa_circRNA_100533 may function as promising diagnostic biomarkers and effective therapeutic targets for OSCC.     

Characteristics of circular RNA expression of pulmonary macrophages in mice with sepsis‐induced acute lung injury

Circular RNAs (circRNAs) make up a large class of non‐coding RNAs and play important roles in the pathology of a variety of diseases. However, their roles in pulmonary macrophage polarization after sepsisinduced lung injury is unknown. In this study, mice were divided into two groups: Sham control group and cecal ligation and puncture (CLP)‐induced ALI group. Macrophages were isolated from lung homogenates 24 hours after SCLP/CLP. We started with RNA‐seq of circRNA changes in macrophages and validated by RT‐PCR in the following experiments. A total of 4318 circRNAs were detected in the two groups. Of these, 11 and 126 circRNAs were found to be significantly upregulated and downregulated, respectively, compared to the control (p≤0.05, Fold Change ≥2). Differentially expressed circRNAs with a high foldchange (fold‐change >4, P<0.05) were selected for validation by qRT‐PCR, 10 of which were verified. Furthermore, the most differentially expressed circRNAs within all the comparisons were annotated in detail with circRNA/miRNA interaction information using miRNA target prediction software. The network of circRNA‐miRNA‐mRNA was illustrated by cytoscape software. Gene ontology analyses indicated the upregulated circRNAs were involved in the multiple biological functions such as regulation of mitochondrion distribution and Notch binding, while the down‐regulated circRNAs mainly involved in the biological process as histone H3K27 methylation. KEGG pathway analysis revealed TGF‐beta signaling pathway was related to the upregulated circRNAs. The present study provides a novel insight into the roles of circRNAs in pulmonary macrophage differentiation and polarization post septic lung injury.     

Circular RNA hsa_circRNA_002178 silencing retards breast cancer progression via microRNA‐328‐3p‐mediated inhibition of COL1A1

Circular RNAs (circRNAs) are a group of non‐coding RNAs implicated in the pathogenesis of cancer progression, which exert their functions via regulation of microRNAs (miRNAs) and genes. The present study uses gain‐ and loss‐of‐function approaches to evaluate the functions of hsa_circRNA_002178 in angiogenesis along with energy metabolism and underlying downstream signals. The expression pattern of hsa_circRNA_002178 in clinical breast cancer tissues and its association with prognosis were characterized at first. Next, the energy metabolism and angiogenesis as well as cell viability were evaluated when the expression of hsa_circRNA_002178 in breast cancer cells was knocked down by siRNA. The interaction between hsa_circRNA_002178 and its downstream miR‐328‐3p was identified, followed by the analysis of their functions in regulation of breast cancer cellular behaviours. The target gene of miR‐328‐3p was predicted and verified, followed by identifying its role in the breast cancer progression. Higher expression of hsa_circRNA_002178 shared an association with worse prognosis in breast cancer. The inhibition of hsa_circRNA_002178 resulted in reductions in cell viability, energy metabolism and tube formation ability. Hsa_circRNA_002178 could competitively bind to miR‐328‐3p and down‐regulated its expression. Restoration of miR‐328‐3p eliminated the tumour‐promoting effects of hsa_circRNA_002178. COL1A1, as a target of miR‐328‐3p, could be up‐regulated by overexpression of hsa_circRNA_002178. In vivo experiments further confirmed the inhibition of tumour growth and inflammation by silencing hsa_circRNA_002178 or up‐regulating miR‐328‐3p. Taken together, hsa_circRNA_002178 is highlighted as a promising target for breast cancer due to the anti‐tumour effects achieved by silencing hsa_circRNA_002178.     

Genome‐Wide Analysis of circular RNAs and validation of hsa_circ_0006719 as a potential novel diagnostic biomarker in congenital scoliosis patients

Congenital scoliosis (CS) is a form of spinal curvature resulting from anomalous development of vertebrae. Recent studies demonstrated that circRNAs could serve as potential biomarkers of disease diagnosis. Genome‐wide circRNAs expression in seven CS patients and three healthy controls was initially detected. Bioinformatics analysis was conducted to explore the potential pathological pathway of CS. Quantitative PCR (qPCR) was performed to validate the selected circRNAs in the replication cohort with 32 CS patients and 30 healthy controls. Logistic regression controlling for gender was conducted to compare the expression difference. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value. Twenty‐two differentially expressed circRNAs were filtered from genome‐wide circRNA sequencing. Seven circRNAs were validated by qPCR. Only hsa_circ_0006719 was confirmed to have a higher expression level in the CS group than the healthy control group (P = 0.036). Receiver operating characteristic curve also suggested that hsa_circ_0006719 had significant diagnostic value for CS (AUC = 0.739, P = 0.001). We described the first study of circRNAs in CS and validated hsa_circ_0006719 as a potential novel diagnostic biomarker of CS.     

Trace the profile and function of circular RNAs in Sertoli cell only syndrome

Studies increasingly show the involvement of circular RNAs (circRNAs) in several diseases. This study aims to explore the circRNA expression pattern in the testicular tissues of patients with Sertoli only cell syndrome (SCOS) and their potential functions. High throughput circRNA microarray analysis indicated that 399 circRNAs were upregulated and 1195 were down-regulated (fold change >2, P < 0.05) in SCOS relative to obstructive azoospermia (OA). The hsa_circRNA_101222, hsa_circRNA_001387, hsa_circRNA_001153, hsa_circRNA_101373 and hsa_circRNA_103864 were validated by qRT-PCR. Furthermore, the hosting genes of the differentially expressed circRNAs (DEcircRNAs) were enriched in biological processes related to cell cycle and intercellular communication. Also, the overlapping genes between the hosting genes of SCOS-related DEcircRNAs and those highly expressed in Sertoli cells of non-obstructive azoospermia (NOA) were enriched in immune cell development and cell communication. Taken together, aberrantly expressed circRNAs likely mediate SCOS development by regulating the function of Sertoli cells and the spermatogenic microenvironment.     

Identification of novel dysregulated circular RNAs in early-stage breast cancer

Breast cancer is a major cause of cancer-related death in women worldwide. Non-coding RNAs are a potential resource to be used as an early diagnostic biomarker for breast cancer. Circular RNAs are a recently identified group of non-coding RNA with a significant role in disease development with potential utility in diagnosis/prognosis in cancer. In this study, we identified 26 differentially expressed circular RNAs associated with early-stage breast cancer. RNA sequencing and two circRNA detection tools (find_circ and DCC) were used to understand the circRNA expression signature in breast cancer. We identified hsa_circ_0006743 (circJMJD1C) and hsa_circ_0002496 (circAPPBP1) to be significantly up-regulated in early-stage breast cancer tissues. Co-expression analysis identified four pairs of circRNA-miRNA (hsa_circ_0023990 : hsa-miR-548b-3p, hsa_circ_0016601 : hsa_miR-1246, hsa_circ_0001946 : hsa-miR-1299 and hsa_circ_0000117:hsa-miR-502-5p) having potential interaction. The miRNA target prediction and network analysis revealed mRNA possibly regulated by circRNAs. We have thus identified circRNAs of diagnostic implications in breast cancer and also observed circRNA-miRNA interaction which could be involved in breast cancer development.     

Clinical significance of circulating microRNAs as diagnostic biomarkers for coronary artery disease

Coronary artery disease (CAD) is one of the biggest threats to human life. Circulating microRNAs (miRNAs) have been reported to be linked to the pathogenesis of CAD, indicating the possible role in CAD diagnosis. The present study aimed to explore the expression profile of plasma miRNAs and estimate their value in diagnosis for CAD. 67 Non‐CAD control subjects and 88 CAD patients were enrolled. We conducted careful evaluation by RT‐PCR analysis, Spearman rank correlation coefficients analysis, Receiver Operating Characteristic (ROC) curves analysis and so on. The plasma levels of six miRNAs known to be related to CAD were measured and three of them showed obvious expression change. Circulating miR‐29a‐3p, miR‐574‐3p and miR‐574‐5p were all significantly increased. ROC analysis revealed the probability of the three miRNAs as biomarkers with AUCs (areas under the ROC curve) of 0.830, 0.792 and 0.789, respectively. They were significantly correlated with each other in CAD patients, suggesting the possibility of joint diagnosis. The combined AUC was 0.915, much higher than each single miRNA. Therefore, our study revealed three promising biomarkers for early diagnosis of CAD. The combination of these miRNAs may act more effectively than individual ones for CAD diagnosis.