Bioinformatics identification of potentially involved microRNAs in Tibetan with gastric cancer based on microRNA profiling

Analysis of lncRNA-miRNA-mRNA Expression in the Troxerutin-Mediated Prevention of Radiation-Induced Lung Injury in Mice

Background

Radiation-induced lung injury (RILI) is a critical factor that leads to pulmonary fibrosis and other diseases. LncRNAs and miRNAs contribute to normal tissue damage caused by ionizing radiation. Troxerutin offers protection against radiation; however, its underlying mechanism remains largely undetermined.

Methods

We established a model of RILI in mice pretreated with troxerutin. The lung tissue was extracted for RNA sequencing, and an RNA library was constructed. Next, we estimated the target miRNAs of differentially expressed (DE) lncRNAs, and the target mRNAs of DE miRNAs. Then, functional annotations of these target mRNAs were performed using GO and KEGG.

Results

Compared to the control group, 150 lncRNA, 43 miRNA, and 184 mRNA were significantly up-regulated, whereas, 189 lncRNA, 15 miRNA, and 146 mRNA were markedly down-regulated following troxerutin pretreatment. Our results revealed that the Wnt, cAMP, and tumor-related signaling pathways played an essential role in RILI prevention via troxerutin using lncRNA-miRNA-mRNA network.

Conclusion

These evidences revealed that the abnormal regulation of RNA potentially leads to pulmonary fibrosis. Therefore, targeting lncRNA and miRNA, along with a closer examination of competitive endogenous RNA (ceRNA) networks are of great significance to the identification of troxerutin targets that can protect against RILI.

Identification of miRNA-mRNA-TFs regulatory network and crucial pathways involved in asthma through advanced systems biology approaches

Asthma is a life-threatening and chronic inflammatory lung disease that is posing a true global health challenge. The genetic basis of the disease is fairly well examined. However, the molecular crosstalk between microRNAs (miRNAs), target genes, and transcription factors (TFs) networks and their contribution to disease pathogenesis and progression is not well explored. Therefore, this study was aimed at dissecting the molecular network between mRNAs, miRNAs, and TFs using robust computational biology approaches. The transcriptomic data of bronchial epithelial cells of severe asthma patients and healthy controls was studied by different systems biology approaches like differentially expressed gene detection, functional enrichment, miRNA-target gene pairing, and mRNA-miRNA-TF molecular networking. We detected the differential expression of 1703 (673 up-and 1030 down-regulated) genes and 71 (41 up-and 30 down-regulated) miRNAs in the bronchial epithelial cells of asthma patients. The DEGs were found to be enriched in key pathways like IL-17 signaling (KEGG: 04657), Th1 and Th2 cell differentiation (KEGG: 04658), and the Th17 cell differentiation (KEGG: 04659) (p-values = 0.001). The results from miRNAs-target gene pairs-transcription factors (TFs) have detected the key roles of 3 miRs (miR-181a-2-3p; miR-203a-3p; miR-335-5p), 6 TFs (TFAM, FOXO1, GFI1, IRF2, SOX9, and HLF) and 32 miRNA target genes in eliciting autoimmune reactions in bronchial epithelial cells of the respiratory tract. Through systemic implementation of comprehensive system biology tools, this study has identified key miRNAs, TFs, and miRNA target gene pairs as potential tissue-based asthma biomarkers.

The prognostic value of MicroRNAs associated with fatty acid metabolism in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the sixth most frequent cancer in humans globally. In addition to smoking and drinking, genetic and epigenetic changes also play a big role in how HNSCC starts and grows. MicroRNAs are short, non-coding RNAs that control cell differentiation and apoptosis by interfering with gene expression. In addition, microRNAs in HNSCC have been shown to affect the clinical behaviors of HNSCC in amazing ways. Moreover, metabolic reprogramming is a key part of cancer and is needed for cancer to turn into a tumor and grow. But it is still not clear what effect microRNAs related to fatty acid metabolism have on the prognosis of HNSCC patients. We downloaded the data of HNSCC patients from the TCGA database and obtained the genes associated with fatty acid metabolism according to the GSEA database. Then, the microRNAs associated with fatty acid metabolism genes were matched. Finally, fatty acid metabolism gene-associated microRNAs for calculating risk scores and then building multifactorial Cox regression models in patients with HNSCC. Heatmap analysis showed that microRNAs involved in fatty acid metabolism were significantly different in HNSCC patients than in healthy controls. A total of 27 microRNAs associated with fatty acid metabolism were screened by univariate Cox analysis (p < 0.05). Using lasso regression, 18 microRNAs substantially linked with the prognosis of HNSCC patients were identified and included in risk scores. The ROC curves demonstrate that risk scores derived from microRNAs involved in fatty acid metabolism can accurately predict the prognosis of HNSCC patients at 1, 3, and 5 years. Moreover, we discovered that 11 microRNAs included in the risk score properly distinguished the prognosis of HNSCC patients. This paper indicated that microRNAs involved with fatty acid metabolism are strongly linked to the prognosis of HNSCC patients. It also indicated that reprogramming of fatty acid metabolism in tumor tissues may play an important role in HNSCC cancer.

microRNA-363-3p reduces endothelial cell inflammatory responses in coronary heart disease via inactivation of the NOX4-dependent p38 MAPK axis

Coronary heart disease (CHD) is one of the leading causes of heart-associated deaths worldwide. This study aimed to investigate the mechanism by which microRNA-363-3p (miR-363-3p) regulates endothelial injury induced by inflammatory responses in CHD. The expression patterns of miR-363-3p, NADPH oxidase 4 (NOX4), and p38 MAPK/p-p38 MAPK were examined in an established atherosclerosis (AS) model in C57BL/6 mice and in isolated coronary arterial endothelial cells (CAECs) after gain- or loss-of-function experiments. We also measured the levels of inflammatory factors (IL-6, ICAM-1, IL-10 and IL-1β), hydrogen peroxide (H₂O₂), and catalase (CAT) activity, followed by detection of cell viability and apoptosis. In AS, miR-363-3p was downregulated and NOX4 was upregulated, while miR-363-3p was identified as targeting NOX4 and negatively regulating its expression. The AS progression was reduced in NOX4 knockout mice. Furthermore, miR-363-3p resulted in a decreased inflammatory response, oxidative stress, and cell apoptosis in CAECs while augmenting their viability via blockade of the p38 MAPK signaling pathway. Overall, miR-363-3p hampers the NOX4-dependent p38 MAPK axis to attenuate apoptosis, oxidative stress injury, and the inflammatory reaction in CAECs, thus protecting CAECs against CHD. This finding suggests the miR-363-3p-dependent NOX4 p38 MAPK axis as a promising therapeutic target for CHD.

Identification of Novel Biomarkers Associated With the Prognosis and Potential Pathogenesis of Breast Cancer via Integrated Bioinformatics Analysis

Background:

Breast cancer is the most commonly diagnosed malignancy and a major cause of cancer-related deaths in women globally. Identification of novel prognostic and pathogenesis biomarkers play a pivotal role in the management of the disease.

Methods:

Three data sets from the GEO database were used to identify differentially expressed genes (DEGs) in breast cancer. Gene Ontology (GO) enrichment and Kyoto Encyclopaedia of Genes and Genomes pathway analyses were performed to elucidate the functional roles of the DEGs. Besides, we investigated the translational and protein expression levels and survival data of the DEGs in patients with breast cancer from the Gene Expression Profiling Interactive Analysis (GEPIA), Oncomine, Human Protein Atlas, and Kaplan Meier plotter tool databases. The corresponding change in the expression level of microRNAs in the DEGs was also predicted using miRWalk and TargetScan, and the expression profiles were analyzed using OncomiR. Finally, the expression of novel DEGs were validated in Chinese breast cancer tissues by RT-qPCR.

Results:

A total of 46 DEGs were identified, and GO analysis revealed that these genes were mainly associated with biological processes involved in fatty acid, lipid localization, and regulation of lipid metabolism. Two novel biomarkers, ADH1A and IGSF10, and 4 other genes (APOD, KIT, RBP4, and SFRP1) that were implicated in the prognosis and pathogenesis of breast cancer, exhibited low expression levels in breast cancer tissues. Besides, 14/25 microRNAs targeting 6 genes were first predicted to be associated with breast cancer prognosis. RT-qPCR results of ADH1A and IGSF10 expression in Chinese breast cancer tissues were consistent with the database analysis and showed significant down-regulation.

Conclusion:

ADH1A, IGSF10, and the 14 microRNAs were found to be potential novel biomarkers for the diagnosis, treatment, and prognosis of breast cancer.

Expression of miR-148b-3p is correlated with overexpression of biomarkers in prostate cancer

Prostate cancer (PCa) is one of the leading causes of death among men. Genes such as PCA3, PSA, and Fra-1 are suggested to serve as potential tools for the detection of PCa, as they are deregulated during this pathology. A similar event occurs with small non-coding RNAs, called miRNAs, specifically miR-195-5p, miR-133a-3p, and miR-148b-3p, which were analyzed in a Chinese population and suggested to be possible candidates for PCa diagnosis. We evaluated the expression levels of three miRNAs and three genes in tissue samples of PCa and benign prostate disease, such as benign prostatic hyperplasia, or prostatitis, in order to determine their potential as candidates for PCa detection. Our results showed a statistically significant overexpression of 279-fold increase in PSA levels and a 1,012-fold increase in PCA3 levels in PCa patients compared to benign prostate disease patients (p = 0.001 and p = 0.002, respectively). We observed a positive correlation between the expression of miR-148b-3p and the expression of PSA and PCA3 genes, two established biomarkers in PCa. The expression of miR-148b-3p was not related to clinical characteristics, such as age and weight, as observed for the other miRNAs analyzed, suggesting its potential as a biomarker for detection of this pathology.

Epigenetic profiling of MUTYH, KLF6, WNT1 and KLF4 genes in carcinogenesis and tumorigenesis of colorectal cancer

Colorectal cancer (CRC) is distinguished by epigenetic elements like DNA methylation, histone modification, histone acetylation and RNA remodeling which is related with genomic instability and tumor initiation. Correspondingly, as a main epigenetic regulation, DNA methylation has an impressive ability in order to be used in CRC targeted therapy. Meaningly, DNA methylation is identified as one of most important epigenetic regulators in gene expression and is considered as a notable potential driver in tumorigenesis and carcinogenesis through gene-silencing of tumor suppressors genes. Abnormal methylation situation, even in the level of promoter regions, does not essentially change the gene expression levels, particularly if the gene was become silenced, leaving the mechanisms of methylation without any response. According to the methylation situation which has a strong eagerness to be highly altered on CpG islands in carcinogenesis and tumorigenesis, considering its epigenetic fluctuations in finding new biomarkers is of great importance. Modifications in DNA methylation pattern and also enrichment of methylated histone signs in the promoter regions of some certain genes like MUTYH, KLF4/6 and WNT1 in different signaling pathways could be a notable key contributors to the upregulation of tumor initiation in CRC. These epigenetic alterations could be employed as a practical diagnostic biomarkers for colorectal cancer. In this review, we will be discuss these fluctuations of MUTYH, KLF4/6 and WNT1 genes in CRC.

miRNA Mediated Noise Making of 3'UTR Mutations in Cancer

Somatic mutations in 3'-untranslated regions (3'UTR) do not alter amino acids and are considered to be silent in cancers. We found that such mutations can promote tumor progression by altering microRNA (miRNA) targeting efficiency and consequently affecting miRNA⁻mRNA interactions. We identified 67,159 somatic mutations located in the 3'UTRs of messenger RNAs (mRNAs) which can alter miRNA⁻mRNA interactions (functional somatic mutations, funcMutations), and 69.3% of these funcMutations (the degree of energy change > 12 kcal/mol) were identified to significantly promote loss of miRNA-mRNA binding. By integrating mRNA expression profiles of 21 cancer types, we found that the expression of target genes was positively correlated with the loss of absolute affinity level and negatively correlated with the gain of absolute affinity level. Functional enrichment analysis revealed that genes carrying funcMutations were significantly enriched in the MAPK and WNT signaling pathways, and analysis of regulatory modules identified eighteen miRNA modules involved with similar cellular functions. Our findings elucidate a complex relationship between miRNA, mRNA, and mutations, and suggest that 3'UTR mutations may play an important role in tumor development.

Predicting MicroRNA-Disease Associations Based on Improved MicroRNA and Disease Similarities

MicroRNAs (miRNAs) are a type of non-coding RNAs with about ∼22nt nucleotides. Increasing evidences have shown that miRNAs play critical roles in many human diseases. The identification of human disease-related miRNAs is helpful to explore the underlying pathogenesis of diseases. More and more experimental validated associations between miRNAs and diseases have been reported in the recent studies, which provide useful information for new miRNA-disease association discovery. In this study, we propose a computational framework, KBMF-MDI, to predict the associations between miRNAs and diseases based on their similarities. The sequence and function information of miRNAs are used to measure similarity among miRNAs while the semantic and function information of disease are used to measure similarity among diseases, respectively. In addition, the kernelized Bayesian matrix factorization method is employed to infer potential miRNA-disease associations by integrating these data sources. We applied this method to 6,084 known miRNA-disease associations and utilized 5-fold cross validation to evaluate the performance. The experimental results demonstrate that our method can effectively predict unknown miRNA-disease associations.

Tetraspanin family identified as the central genes detected in gastric cancer using bioinformatics analysis

Gastric cancer has become a serious disease in the past decade. It has the second highest mortality rate among the four most common cancer types, leading to ~700,000 mortalities annually. Previous studies have attempted to elucidate the underlying biological mechanisms of gastric cancer. The present study aimed to obtain useful biomarkers and to improve the understanding of gastric cancer mechanisms at the genetic level. The present study used bioinformatics analysis to identify 1,829 differentially expressed genes (DEGs) which were obtained from the GSE54129 dataset. Using protein‑protein interaction information from the Search Tool for the Retrieval of Interacting Genes database, disease modules were constructed for gastric cancer using Cytoscape software. In the Gene Ontology analysis of biology processes, upregulated genes were significantly enriched in 'extracellular matrix organization', 'cell adhesion' and 'inflammatory response', whereas downregulated DEGs were significantly enriched in 'xenobiotic metabolic process', 'oxidation‑reduction process' and 'steroid metabolic process'. During Kyoto Encyclopedia of Genes and Genomes analysis, upregulated DEGs were significantly enriched in 'extracellular matrix‑receptor interaction', 'focal adhesion' and 'PI3K‑Akt signaling pathway', whereas the downregulated DEGs were significantly enriched in 'chemical carcinogenesis', 'metabolism of xenobiotics by cytochrome P450' and 'peroxisome'. The present study additionally identified 10 hub genes from the DEGs: Tumor protein p53 (TP53), C‑X‑C motif chemokine ligand 8 (CXCL8), tetraspanin 4 (TSPAN4), lysophosphatidic acid receptor 2 (LPAR2), adenylate cyclase 3 (ADCY3), phosphoinositide‑3‑kinase regulatory subunit 1 (PIK3R1), neuromedin U (NMU), C‑X‑C motif chemokine ligand (CXCL12), fos proto‑oncogene, AP‑1 transcription factor subunit (FOS) and sphingosine‑1‑phosphate receptor 1 (S1PR1), which have high degrees with other DEGs. The survival analysis revealed that the high expression of ADCY3, LPAR2, S1PR1, TP53 and TSPAN4 was associated with a lower survival rate, whereas high expression of CXCL8, FOS, NMU and PIK3R1 was associated with a higher survival rate. No significant association was identified between CXCL12 and survival rate. Additionally, TSPAN1 and TSPAN8 appeared in the top 100 DEGs. Finally, it was observed that 4 hub genes were highly expressed in gastric cancer tissue compared with para‑carcinoma tissue in the 12 patients; the increased TSPAN4 was significant (>5‑fold). Tetraspanin family genes may be novel biomarkers of gastric cancer. The findings of the present study may improve the understanding of the molecular mechanisms underlying the development of gastric cancer.

The Role of HOTAIR/miR-148b-3p/USF1 on Regulating the Permeability of BTB

Homeobox transcript antisense intergenic RNA (HOTAIR), as a long non-coding RNA (lncRNA), has been considered to play critical roles in the biological properties of various tumors. The purposes of this study were to investigate the role and possible molecular mechanisms of HOTAIR in regulating the permeability of blood tumor barrier (BTB) in vitro. Our present study elucidated that the expressions of HOTAIR and upstream stimulatory factor 1 (USF1) was up-regulated, but miR-148b-3p was down-regulated in glioma microvascular endothelial cells (GECs). Knockdown of HOTAIR could increase the permeability of BTB as well as down-regulated the expressions of tight junction related proteins ZO-1, occludin, claudin-5, but up-regulated miR-148b-3p expressions in GECs. Meanwhile, dual-luciferase reporter assays demonstrated that HOTAIR was a target RNA of miR-148b-3p. Furthermore, overexpression of miR-148b-3p increased the permeability of BTB by down-regulating the expressions of tight junction related proteins and USF1 in GECs, and vice versa. And further result revealed USF1 was a target of miR-148b-3p. Silence of USF1 increased the permeability of BTB duo to their interaction with the promoters of ZO-1, occludin, and claudin-5 in GECs. Taken together, our finding indicated that knockdown of HOTAIR increased BTB permeability via binding to miR-148b-3p, which further reducing tight junction related proteins in GECs by targeting USF1. Thus, HOTAIR will attract more attention since it can serve as a potential target of drug delivery across BTB and may provide novel strategies for glioma treatment.

Maternal Low-Protein Diet Modulates Glucose Metabolism and Hepatic MicroRNAs Expression in the Early Life of Offspring †

Emerging studies revealed that maternal protein restriction was associated with increased risk of type 2 diabetes mellitus in adulthood. However, the mechanisms of its effects on offspring, especially during early life of offspring, are poorly understood. Here, it is hypothesized that impaired metabolic health in offspring from maternal low-protein diet (LPD) is associated with perturbed miRNAs expression in offspring as early as the weaning age. We examined the metabolic effects on the C57BL/6J mice male offspring at weaning from dams fed with LPD or normal chow diet (NCD) throughout pregnancy and lactation. Maternal LPD feeding impaired metabolic health in offspring. Microarray profiling indicated that mmu-miR-615, mmu-miR-124, mmu-miR-376b, and mmu-let-7e were significantly downregulated, while, mmu-miR-708 and mmu-miR-879 were upregulated in LPD offspring. Bioinformatic analysis showed target genes were mapped to inflammatory-related pathways. Serum tumor necrosis factor-α (TNF-α) levels were higher and interleukin 6 (IL-6) had a tendency to be elevated in the LPD group. Finally, both mRNA and protein levels of IL-6 and TNF-α were significantly increased in the LPD group. Our findings provide novel evidence that maternal LPD can regulate miRNAs expression, which may be associated with chronic inflammation status and metabolic health in offspring as early as the weaning age.

Maternal high-calorie diet is associated with altered hepatic microRNA expression and impaired metabolic health in offspring at weaning age

High-calorie diet (HCD) feeding in mice predisposes offspring for impaired glucose homeostasis and obesity. However, the mechanisms underlying these detrimental effects of maternal nutrition, especially during early life of offspring, are incompletely understood. MicroRNAs (miRNAs) are small non-coding RNAs that can regulate target gene expression. Here we hypothesized that impaired metabolic health in offspring from HCD-fed dams at weaning is associated with dysregulated expression of hepatic miRNAs. Dams were fed a chow diet (CD; 11.4 % kcal fat, 62.8 % from carbohydrate, 25.8 % from protein) or HCD (58 % kcal from fat; 25.6 % from carbohydrate, 16.4 % from protein) during gestation and lactation, and metabolic health was assessed in male offspring at weaning. Hepatic levels of miRNAs and target genes were investigated in offspring from CD- or HCD-fed dams using gene and protein expression. Maternal HCD feeding impaired metabolic health in offspring compared to offspring from CD-fed dams. Microarray analysis indicated that expressions of miR-615-5p, miR-3079-5p, miR-124*, and miR-101b* were downregulated, whereas miR-143* was upregulated, in livers from offspring from HCD-fed dams. Our functional enrichment analysis indicated that the target genes of these differentially expressed miRNAs, including tumor necrosis factor-α (TNF-α) and mitogen-activated protein kinase 1 (MAPK1), were mapped to inflammatory pathways. Finally, we verified that both mRNA and protein levels of the pro-inflammatory modulators TNF-α and MAPK1 were significantly increased in livers of offspring from HCD-fed dams at weaning. Maternal HCD feeding predisposes offspring to a higher body weight and impaired glucose metabolism at weaning. To the best of knowledge, our study is the first to show that maternal HCD consumption impairs metabolic health, modulates hepatic miRNA expression, and increases markers of hepatic inflammation in offspring as early as at weaning age.

Noncoding RNAs in gastric cancer: Research progress and prospects

Noncoding RNAs (ncRNAs) have attracted much attention in cancer research field. They are involved in cellular development, proliferation, differentiation and apoptosis. The dysregulation of ncRNAs has been reported in tumor initiation, progression, invasion and metastasis in various cancers, including gastric cancer (GC). In the past few years, an accumulating body of evidence has deepened our understanding of ncRNAs, and several emerging ncRNAs have been identified, such as PIWI-interacting RNAs (piRNAs) and circular RNAs (circRNAs). The competing endogenous RNA (ceRNA) networks include mRNAs, microRNAs, long ncRNAs (lncRNAs) and circRNAs, which play critical roles in the tumorigenesis of GC. This review summarizes the recent hotspots of ncRNAs involved in GC pathobiology and their potential applications in GC. Finally, we briefly discuss the advances in the ceRNA network in GC.

Identification and functional characterization of microRNAs reveal a potential role in gastric cancer progression

PURPOSE

To investigate the potential candidate microRNA (miRNA) biomarkers for the clinical diagnosis, classification, and prognosis of gastric cancer (GC).

METHODS

We use bioinformatics overlapping subclasses analysis to find the tumor grade and lymphatic metastasis-related GC specific miRNAs from the Cancer Genome Atlas (TCGA) database. Then, we further investigated these GC specific miRNAs distributions in different GC clinical features and their correlations overall survival on the basis of GC patients' information and their related RNA sequencing profile from TCGA. Finally, we randomly selected some of key miRNAs use qRT-PCR to confirm the reliability and validity.

RESULTS

22 GC specific key miRNAs were identified (Fold-change >2, P < 0.05), 11 of them were discriminatively expressed with tumor size, grade, TNM stage and lymphatic metastasis (P < 0.05). In addition, nine miRNAs (miR-196b-5p, miR-135b-5p, miR-183-5p, miR-182-5p, miR-133a-3p, miR-486-5p, miR-144-5p, miR-129-5p and miR-145-5p) were found to be significantly associated with overall survival (log-rank P < 0.05). Finally, four key miRNAs (miR-183-5p, miR-486-5p, miR-30c-2-3p and miR-133a-3p) were randomly selected to validation and their expression levels in 53 newly diagnosed GC patients by qRT-PCR. Results showed that the fold-changes between TCGA and qRT-PCR were 100 % in agreement. We also found miR-183-5p and miR-486-5p were significantly correlated with tumor TNM stage (P < 0.05), and miR-30c-2-3p and miR-133a-3p were associated with tumor differentiation degree and lymph-node metastasis (P < 0.05). These verified miRNAs clinically relevant, and the bioinformatics analysis results were almost the same.

CONCLUSION

These key miRNAs may functions as potential candidate biomarkers for the clinical diagnosis, classification and prognosis for GC.