Oncogenic role of microRNA-423-5p in hepatocellular carcinoma

Non-coding RNA-associated competitive endogenous RNA regulatory networks: Novel diagnostic and therapeutic opportunities for hepatocellular carcinoma

Hepatocellular carcinoma (HCC), as the most prevalent liver malignancy, is annually diagnosed in more than half a million people worldwide. HCC is strongly associated with hepatitis B and C viral infections as well as alcohol abuse. Obesity and nonalcoholic fatty liver disease (NAFLD) also significantly enhance the risk of liver cancer. Despite recent improvements in therapeutic approaches, patients diagnosed in advanced stages show poor prognosis. Accumulating evidence provides support for the regulatory role of non-coding RNAs (ncRNAs) in cancer. There are a variety of reports indicating the regulatory role of microRNAs (miRNAs) in different stages of HCC. Long non-coding RNAs (LncRNAs) exert their effects by sponging miRNAs and controlling the expression of miRNA-targeted genes. Circular RNAs (circRNAs) perform their biological functions by acting as transcriptional regulators, miRNA sponges and protein templates. Diverse studies have illustrated that dysregulation of competing endogenous RNA networks (ceRNETs) is remarkably correlated with HCC-causing diseases such as chronic viral infections, nonalcoholic steatohepatitis and liver fibrosis/cirrhosis. The aim of the current article was to provide an overview of the role and molecular mechanisms underlying the function of ceRNETs that modulate the characteristics of HCC such as uncontrolled cell proliferation, resistance to cell death, metabolic reprogramming, immune escape, angiogenesis and metastasis. The current knowledge highlights the potential of these regulatory RNA molecules as novel diagnostic biomarkers and therapeutic targets in HCC.

Silencing of long noncoding RNA H19 alleviates pulmonary injury, inflammation, and fibrosis of acute respiratory distress syndrome through regulating the microRNA-423-5p/FOXA1 axis

PURPOSE

This study aimed to explore the regulatory effects and mechanisms of long noncoding RNA H19 (H19) on pulmonary injury, inflammation, and fibrosis of acute respiratory distress syndrome (ARDS).

MATERIALS AND METHODS

A rat model of ARDS was established by intratracheal instillation of 2 mg/kg lipopolysaccharide (LPS). qRT-PCR was performed to detect the expression of H19, miR-423-5p, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, monocyte chemoattractant protein (MCP)-1, and vascular endothelial growth factor (VEGF). Histology score was assessed by hematoxylin-eosin (HE) staining. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of proinflammatory cytokines and the content of VEGF in bronchoalveolar lavage fluid (BALF). The lung fibrosis was evaluated using western blot and Masson's trichrome staining. Dual-luciferase reporter gene assay was used for confirming the relationship between miR-423-5p and H19/FOXA1 in alveolar macrophage cells (MH-S) and alveolar epithelial cells (MLE-12). The regulatory effects of H19/miR-423-5p/FOXA1 axis on the inflammation and fibrosis were further analyzed in LPS-induced MH-S cells.

RESULTS

The expression of H19 and FOXA1 was significantly up-regulated, while the expression of miR-423-5p was down-regulated in LPS-induced ARDS rats. Silencing of H19 decreased the mRNA expression of TNF-α, IL-1β, IL-6, MCP-1, and VEGF, the contents of TNF-α, IL-1β, IL-6, and VEGF in BALF, and histology score in LPS-induced ARDS rats. H19 knockdown also reduced the fibrosis scores and the protein expression of vimentin and α-SMA, and elevated the protein expression of E-cadherin in LPS-induced ARDS rats. Furthermore, silencing of miR-423-5p and overexpression of FOXA1 reversed the inhibitory effects of si-H19 on the inflammation and fibrosis of LPS-induced MH-S cells.

CONCLUSIONS

Silencing of H19 relieved the pulmonary injury, inflammation and fibrosis of LPS-induced ARDS in rats. Silencing of H19 also alleviated the inflammation and fibrosis of LPS-induced MH-S cells through regulating the miR-423-5p/FOXA1 axis.

FKBP-related ncRNA-mRNA axis in breast cancer

Breast cancer (BC) is a disease with morbidity ranking the first of women worldwidely. In current study, 11 DE-miRNAs, consisting of four FKBP4 related DE-miRNAs and seven FKBP5 related DE-miRNAs, were screened. Four hundred and eighty two predicted lncRNAs were found for DE-miRNAs. Then, expression and prognostic results of nine of top 20 lncRNAs of BC were significantly identified. LINC00662 and LINC00963 expression were significantly associated with patients' overall survival (OS). Then, nine potential upstream transcription factors were identified in motifs of DE-miRNAs. Three hundred and twenty target genes were identified for GO annotation and KEGG pathway analysis, which were mainly enriched in cysteine-type endopeptidase activity involved in apoptotic process. Construction and analysis in PPI network showed that RAB7A was selected as a hub gene with the topest connectivity scores. Differential expression analysis of nine in top ten hub genes of BC were significantly identified. RAB7A and ARRB1 expression were significantly related with BC patients' OS.

Identification of microRNA expression signature for the diagnosis and prognosis of cervical squamous cell carcinoma

Cervical cancer is the fourth leading cause of cancer death among women globally. The prognosis of cervical cancer patients differs considerably, and clinical outcomes are difficult to predict. Given the significant roles of miRNAs in human cancers, identification of novel and reliable miRNA biomarkers is important for targeted cervical cancer therapy. In the present study, we aimed to reveal biological significance of miR-200a, miR-423, miR-34a, miR-193a, and miR-455 for the prognosis and diagnosis of cervical cancer and their association with the clinical outcomes of patients. Distinct expression profiles of miRNAs in formalin-fixed paraffin-embedded tissue samples of patients and healthy controls were evaluated using qRT-PCR. We identified miR-200a, miR-455, and miR-34a were significantly downregulated in cervical squamous cell carcinoma tissues compared to normal cervix tissue from healthy controls. Both miR-455 and miR-34a confer a promising diagnostic factor for the cervical cancer while miR-200a showed no significance in ROC analysis. Notably, low expression of miR-34a was markedly associated with the poor overall survival of cervical cancer patients as revealed by Kaplan-Meier survival analysis. Also, univariate and multivariate analysis indicated miR-34a expression as an independent prognostic factor. Consequently, our results underline the importance of distinct expression miRNAs in cervical squamous cell carcinoma.

Long Non-coding RNA FENDRR Acts as a miR-423-5p Sponge to Suppress the Treg-Mediated Immune Escape of Hepatocellular Carcinoma Cells

Long non-coding RNAs (lncRNAs) have been known to partake in the development and the immune escape of hepatocellular carcinoma (HCC). The initial microarray analysis of GSE115018 expression profile revealed differentially expressed lncRNA fetal-lethal non-coding developmental regulatory RNA (FENDRR) in HCC. Therefore, this study’s main purpose was to explore the mechanism of tumor suppressor lncRNA FENDRR in regulating the immune escape of HCC cells. Notably, it was further validated through this study that lncRNA FENDRR competitively bound to microRNA-423-5p (miR-423-5p), and miR-423-5p specifically targeted growth arrest and DNA-damage-inducible beta protein (GADD45B). The effects that lncRNA FENDRR and miR-423-5p have on the cell proliferation and apoptosis, the immune capacity of regulatory T cells (Tregs), and the tumorigenicity of HCC cells were examined through overexpressing or the knocking down of lncRNA FENDRR and miR-423-5p both in vitro and in vivo. Subsequently, lncRNA FENDRR and GADD45B were revealed to have poor expressions in HCC. Meanwhile, miR-423-5p was highly expressed in HCC. Importantly, overexpressed lncRNA FENDRR and downregulated miR-423-5p diminished cell proliferation and tumorigenicity, and promoted apoptosis in HCC cells, thus regulating the immune escape of HCC mediated by Tregs. Taken conjointly, lncRNA FENDRR inhibited the Treg-mediated immune escape of HCC cells by upregulating GADD45B by sponging miR-423-5p.

Potential clinical value and putative biological function of miR-122-5p in hepatocellular carcinoma: A comprehensive study using microarray and RNA sequencing data

In order to determine the diagnostic efficacy of microRNA (miR)-122-5p and to identify the potential molecular signaling pathways underlying the function of miR-122-5p in hepatocellular carcinoma (HCC), the expression profiles of data collected from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and literature databases were analyzed, along with any associations between clinicopathological characteristics and the diagnostic value of miR-122-5p in HCC. The intersection of 12 online prediction databases and differentially expressed genes from TCGA and GEO were utilized in order to select the prospective target genes of miR-122-5p in HCC. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction network (PPI) analyses were subsequently performed based on the selected target genes. The average expression level of miR-122-5p was decreased in HCC patients compared with controls from TCGA database (P<0.001), and the downregulation of miR-122-5p was significantly associated with HCC tissues (P<0.001), tumor vascular invasion (P<0.001), metastasis (P=0.001), sex (P=0.006), virus infection status (P=0.001) and tissue (compared with serum; P<0.001) in cases from the GEO database. The pooled sensitivity and specificity for miR-122-5p to diagnose HCC were 0.60 [95% confidence interval (CI), 0.48–0.71] and 0.81 (95% CI, 0.70–0.89), respectively. The area under the curve (AUC) value was 0.76 (95% CI, 0.72–0.80), while in Meta-DiSc 1.4, the AUC was 0.76 (Q*=0.70). The pooled sensitivity and specificity were 0.60 (95% CI, 0.57–0.62) and 0.79 (95% CI, 0.76–0.81), respectively. A total of 198 overlapping genes were selected as the potential target genes of miR-122-5p, and 7 genes were defined as the hub genes from the PPI network. Cell division cycle 6 (CDC6), minichromosome maintenance complex component 4 (MCM4) and MCM8, which serve pivotal functions in the occurrence and development of HCC, were the most significant hub genes. The regulation of cell proliferation for cellular adhesion and the biosynthesis of amino acids was highlighted in the GO and KEGG pathway analyses. The downregulation of miR-122-5p in HCC demonstrated diagnostic value, worthy of further attention. Therefore, miR-122-5p may function as a tumor suppressor by modulating genome replication.

Establishment of an easy and straight forward heparinase protocol to analyse circulating and myocardial tissue micro-RNA during coronary artery-bypass-graft surgery

Coronary artery-bypass-graft (CABG) surgery is associated with myocardial damage and increased blood concentrations of circulating microRNAs (miRNA). However, whether and to what extent these miRNAs relate to cardiac tissue miRNA expression have not yet been explored. Since plasma miRNA quantification in samples from cardiopulmonary bypass (CPB) patients is severely hampered by heparin, we established and validated successfully a protocol to reliably measure miRNA in 49 heparinized patients undergoing CABG so as to investigate the relationship between circulating and right atrial miRNAs. Plasma and right atrial expression of miR-1, miR-133a, miR-423-5p, and miR-499 were measured before and after CPB, as well as miRNAs in plasma 24 h thereafter. All plasma miRNAs increased significantly with surgery while cardiac tissue expression of only miR-133a (1.4-fold; p = 0.003) and miR-423-5p (1.3 fold; p = 0.025) increased as well. Right atrial and plasma miR-133a expression correlated positively before CPB (r = 0.288, p = 0.045) but miR-499 expression inversely (r = −0.484, p = 0.0004). There was a strong association between plasma miR-133a and miR-499 concentrations and postoperative troponin I concentrations, the marker for myocardial damage. Increased myocardial miR-133a and miR-423-5p expression together with unchanged miR-1 and miR-499 expression might suggest active release of these miRNAs rather than their origin from damaged cells.

Administration of alpha-ketoglutarate improves epithelial restitution under stress injury in early-weaning piglets

Alpha-ketoglutarate (AKG) is an important cellular metabolite that participates in energy production and amino acid metabolism. However, the protective effects and mechanism of AKG on mucosal lesions have not been well understood. This study was conducted to investigate the effects of dietary AKG supplementation on epithelial restitution in early-weaning piglets under Escherichia coli lipopolysaccharide (LPS) induction. A total of 32 weaned piglets were used in a 2 × 2 factorial design; the major factors were dietary treatment (basal diet or AKG diet) and inflammatory challenge (LPS or saline). The results showed that AKG supplementation improved the growth performance and intestinal morphology in the LPS-induced early-weaning piglets. Compared with the basal diet, the AKG diet remarkably decreased the concentration and mRNA expression of intestinal inflammatory cytokines (IL-1β, IL-6, and IL-12) in the LPS-induced piglets. Moreover, AKG administration upregulated the mRNA expression of nutrient-sensing transporters (GLUT-2, SGLT-1, PEPT-1, I-FABP2) in the small intestine of both saline- and LPS-treated piglets, and improved the distribution and expression of tight-junction genes andproteins (ZO-1, Occludin, Claudins, E-cadherin). Collectively, our findings indicate that AKG has the potential to alleviate intestinal inflammatory response and improve epithelial restitution and nutrient-sensing ability under stress injury in early-weaning piglets, and it also provides an experimental basis for enteral use of AKG in swine production and clinical application to prevent intestinal epithelial damage.

Identification of a functional polymorphism affecting microRNA binding in the susceptibility locus 1q25.3 for colorectal cancer

Genome-wide association studies (GWASs) have identified dozens of susceptibility loci for colorectal cancer (CRC). However, most of them lack functional genetic variants and clear biological mechanisms. MicroRNAs (miRNAs) are small noncoding RNAs involved in a variety of physiological and tumorigenic processes. Here we hypothesized that single nucleotide polymorphisms (SNPs) that affect miRNAs biogenesis and binding, could contribute to CRC risk in the Chinese population. To locate miRNA-related SNPs in established GWAS loci, we initially screened out five candidate SNPs using a systematic bioinformatics analysis. Then, we performed a two-stage case-control study consisting of 2347 cases and 3390 controls, and found a positive polymorphism rs1062044, which presented consistently significant associations with CRC in both stages, and with an odds ratio (OR) = 1.32 (95% confidence interval (95%CI) = 1.18-1.49, P = 3.43E-06) under the dominant model in the combined study. Further luciferase reporter gene assays indicated that the variant G allele obviously improved the specific binding between miR-423-5p and the gene LAMC1. These findings suggested that the functional SNP rs1062044 at 1q25.3 might be a genetic modifier for the occurrence and development of CRC.