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Background/Aims: Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Our study investigated the functional role of miR-212-5p in TNBC. Methods: Realtime PCR was used to quantify miR-212-5p expression levels in 30 paired TNBC samples and adjacent normal tissues. Wound healing and Transwell assays were used to evaluate the effects of miR-212-5p expression on the invasiveness of TNBC cells. Luciferase reporter and Western blot assays were used to verify whether the mRNA encoding Prrx2 is a major target of miR-212-5p. Results: MiR-212-5p was downregulated in TNBC, and its expression levels were related to tumor size, lymph node status and vascular invasion in breast cancer. We also observed that the miR-212-5p expression level was significantly correlated with a better prognosis in TNBC. Ectopic expression of miR-212-5p induced upregulation of E-cadherin expression and downregulation of vimentin expression. The expression of miR212-5p also suppressed the migration and invasion capacity of mesenchymal-like cancer cells accompanied by a morphological shift towards the epithelial phenotype. Moreover, our study observed that miR-212-5p overexpression significantly suppressed Prrx2 by targeting its 3’-untranslated region (3’-UTR) region, and Prrx2 overexpression partially abrogated miR-212-5p-mediated suppression. Conclusions: Our study demonstrated that miR-212-5p inhibits TNBC from acquiring the EMT phenotype by downregulating Prrx2, thereby inhibiting cell migration and invasion during cancer progression. [ABSTRACT FROM AUTHOR]

Previously, a surgical regression model identified micro RNA-101b ( miR-101b) as a potential inhibitor of cardiac hypertrophy. Here, we investigated the antihypertrophic mechanism of miR-101b using neonatal rat ventricular myocytes. miR-101b markedly suppressed agonist-induced cardiac hypertrophy as shown by cell size and fetal gene expression. By systems biology approaches, we identified protein kinase C epsilon ( PKCε) as the major target of miR-101b. Our results from qRT- PCR, western blot, and luciferase reporter assays confirm that PKCε is a direct target of miR-101b. In addition, we found that effectors downstream of PKCε (p- AKT, p- ERK1/2, p- NFAT, and p- GSK3β) are also affected by miR-101b. Our study reveals a novel inhibitory mechanism for miR-101b as a negative regulator of cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

Acute myocardial infarction (AMI) is a cardiovascular disease with high morbidity and mortality, and microRNA-139-5p (miR-139-5p) has been reported to be closely related with myocardial viability. This study aimed to investigate the effects of miR-139-5p on vascular endothelial cells, detect miR-139-5p expression in AMI patients and evaluate its diagnostic value. A dual-luciferase reporter assay was utilized to confirm the interaction of miR-139-5p with vascular endothelial growth factor receptor-1 (VEGFR-1). Quantitative real-time PCR was used to detect the levels of miR-139-5p and VEGFR-1 in serum and cells. The viability of human umbilical vein endothelial cells (HUVECs) was measured using a cell counting kit-8 assay. The correlation between miR-139-5p and VEGFR-1 was analyzed by Pearson correlation analysis. The diagnostic value of miR-139-5p, cardiac troponin I (cTnI) and creatine kinase isoenzymes (CK-MB) was identified by receiver operating characteristic analysis. miR-139-5p suppressed cell viability by directly targeting VEGFR-1 in HUVECs. Increased miR-139-5p and decreased VEGFR-1 levels were found in AMI patients and hypoxia-treated HUVECs, and miR-139-5p and VEGFR-1 were shown to be negatively correlated. The diagnostic value of miR-139-5p for AMI screening was high, and the combination of cTnI, CK-MB and miR-139-5p had the highest diagnostic accuracy. miR-139-5p inhibited cell viability by inhibiting VEGFR-1 in hypoxia-treated HUVECs. miR-139-5p inhibits endothelial cell viability of AMI by inhibiting VEGFR-1, and increased miR-139-5p expression in AMI patients has high diagnostic value for AMI screening, indicating that miR-139-5p may serve as a diagnostic biomarker and molecular therapeutic target for AMI. • miR-139-5p suppressed HUVEC viability by directly inhibiting VEGFR-1. • miR-139-5p was upregulated and VEGFR-1 was downregulated in AMI patients. • Serum miR-139-5p was negatively correlated with serum VEGFR-1. • Increased miR-139-5p had relatively high diagnostic accuracy in AMI. • High miR-139-5p suppressed hypoxia-treated HUVEC viability by inhibiting VEGFR-1. [ABSTRACT FROM AUTHOR]

Background: Although cisplatin-based chemotherapy represents the standard regimen for osteosarcoma (OS), OS patients often exhibit treatment failure and poor prognosis due to chemoresistance to cisplatin. Emerging research has highlighted the tumor suppressive properties of microRNAs (miRNAs or miRs) in various human cancers via the inhibition of the histone demethylase jumonji domain containing protein 2C (JMJD2C). As a coactivator for hypoxia-inducible factor 1α (HIF1α), JMJD2C targets hairy and enhancer of split-1 (HES1) gene. Hence, the current study aimed to elucidate the role of miR-216b in OS cell cisplatin resistance to identify the underlying mechanism of miR-216b regulating the JMJD2C//HIF1α/HES1 signaling. Methods: Tumor and paracancerous tissues were collected from OS patients to determine the expression patterns of miR-216b and JMJD2C. After ectopic expression and knockdown experiments in the OS cells, CCK-8 assay and flow cytometry were employed to determine cell viability and apoptosis. The interaction of miR-216b, JMJD2C, HIF1α and HES1 was subsequently determined by dual luciferase reporter, co-immunoprecipitation (IP) and ChIP-qPCR assays. In vivo experiments were conducted to further verify the role of the miR-216b in the resistance of OS cells to cisplatin. Results: miR-216b expression was reduced in the OS tissues, as well as the MG63 and SaOS-2 cells. Heightened miR-216b expression was found to be positively correlated with patient survival, and miR-216b further enhanced cisplatin-induced apoptosis of MG63 and SaOS-2 cells. Mechanistically, miR-216b inhibited JMJD2C expression by binding to its 3'UTR. Through interaction with HIF1α, JMJD2C removed the H3K9 methylation modification at the HES1 promoter region, leading to upregulation of HES1 in vitro. Furthermore, miR-216b was observed to increase the tumor growth in nude mice in the presence of cisplatin treatment. HES1 overexpression weakened the effects of miR-216b in MG63 and SaOS-2 cells and in nude mouse xenografts. Conclusion: Overall, miR-216b enhanced the sensitivity of OS cells to cisplatin via downregulation of the JMJD2C/HIF1α/HES1 signaling axis, highlighting the capacity of miR-216b as an adjunct to cisplatin chemotherapy in the treatment of OS. [ABSTRACT FROM AUTHOR]

Serum microRNAs (miRNAs) have been implicated as noninvasive biomarkers for lung cancer diagnosis. However, there are no sensitive and specific biomarkers for the detection of radiotherapy-related non-small cell lung cancer (NSCLC) metastasis. The present study aimed to investigate the role of three serum miRNAs, namely miRNA (miR)-130a, miR-25 and miR-191*, in diagnosing NSCLC, and their biological functions in radiation-mediated development of metastatic properties in A549 cells. To determine this, serum samples were collected from 84 patients with NSCLC and 42 age- and sex-matched healthy controls. Differential expression of serum miRNAs was analyzed by quantitative PCR. Significant associations between miRNA expression and overall survival of patients with NSCLC were identified using the Cox proportional regression model. A receiver operating characteristic curve was generated to evaluate diagnostic accuracy. The functions of miR-130a, miR-25 and miR-191* in lung cancer cells were studied by transfecting A549 cells with miRNA mimics and inhibitors. The results of the present study demonstrated that the expression levels of miR-130a, miR-25 and miR-191* in the serum of patients with NSCLC were increased compared with those in healthy controls, and these increases were associated with advanced age (=60 years), radiotherapy, histological type (squamous carcinoma), low survival rate and low median survival time. Additionally, irradiation induced the upregulation of miR-130a, miR-25 and miR-191* expression in A549 cells in vitro and in a xenograft mouse model. Irradiation also promoted the invasiveness of A549 cells in vitro and metastasis in vivo. In conclusion, miR-130a, miR-25 and miR-191* may be potential biomarkers for the diagnosis of patients with NSCLC and may serve oncogenic roles in radiation-mediated metastasis of NSCLC. [ABSTRACT FROM AUTHOR]

Abstract Gastric cancer is the second most leading cause of cancer related mortality across the world over. Although the incidence of GC has declined to some extent but it is still the fourth highly diagnosed cancer across the world. GC generally remains undiagnosed till advanced stages due to unavailability of biomarkers and when diagnosed it becomes difficult to manage due to the lack of therapeutic targets and efficient chemotherapy. There are concrete evidences suggesting that miRNAs may prove important therapeutic targets for the treatment of devastating diseases such as cancer. The study was designed to investigate the tumor suppressive role of miR-31 via regulation of zeste homolog 2 (ZH2). It was found that miR-31 is significantly downregulated in GC cell lines. Overexpression of miR-31 causes significant (P < 0.05) decrease in the viability and colony formation via initiation of G2/M cell cycle arrest of the AGS cancer cells. Moreover, miR-31 overexpression also enhanced the chemosensitivity of miR-31 to the anticancer drug 5-fluorouracil. In silico analysis together with dual luciferase reporter assay indicated zeste homolog 2 (ZH2) to be the potential target of miR-31 in AGS cells. Investigation of ZH2 expression in GC cell lines showed it to be significantly (P < 0.05) upregulated. Nonetheless, overexpression of miR-31 in AGS cells resulted in the suppression of ZH2 expression. Additionally, silencing of ZH2 in the AGS cells also caused inhibition of AGS cell proliferation and colony formation via G2/M arrest. Moreover, overexpression of ZH2 could at least partially reverse the tumor suppressive effects of miR-31 indicating direct involvement of ZH2 in the miR-31 mediated inhibitory effects on AGS cell proliferation. Finally, miR-31 overexpression caused significant (P < 0.05) inhibition of the migration and invasion of the AGS gastric cancer cells. The overexpression of miR-31 also caused downregulation of mesenchymal markers (Vimentin and N-cadherin) and upregulation of epithelial marker (E-cadherin) protein expression was in AGS cells. It is therefore concluded that miR-31 acts as a tumor suppressor and may prove essential in the treatment of GC. [ABSTRACT FROM AUTHOR]

Previous work has demonstrated that the expression of microRNA-21 (miR-21) is implicated in cervical cancer (CC). However, little is known regarding its associations with clinical parameters. We first conducted a meta-analysis using data from Gene Expression Omnibus (GEO) microarrays and The Cancer Genome Atlas (TCGA). Then, enrichment analysis and hub gene screening were performed by bioinformatic methods. Finally, the role of the screened target genes in CC was explored. According to the meta-analysis, the expression of miR-21 in cancer tissues was higher than in adjacent nontumor tissues (P < 0.05). In addition, 46 genes were predicted as potential targets of miR-21. After enrichment analyses, it was detected that these genes were enriched in various cancer pathways, including the phosphatidylinositol signaling system and mammalian target of rapamycin (mTOR) signaling pathway. In this study, bioinformatic tools and meta-analysis validated that miR-21 may function as a highly sensitive and specific marker for the diagnosis of CC, which may provide a novel approach to the diagnosis and treatment of CC. [ABSTRACT FROM AUTHOR]

Cervical cancer is a common malignant disease that poses a serious health threat to women worldwide. Growing research efforts have focused on protein-coding and non-coding RNAs involved in the tumorigenesis and prognosis of various types of cancer. The potential molecular mechanisms and the interaction among long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and mRNAs require further investigation in cervical cancer. In the present study, lncRNA, miRNA, and mRNA expression profiles of 304 primary tumor tissues from patients with cervical cancer and 3 solid normal tissues from The Cancer Genome Atlas (TCGA) dataset were studied via RNA sequencing (RNA-seq). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed using R package clusterProfiler to annotate the principal functions of differentially expressed (DE) mRNAs. Kaplan-Meier analysis was also conducted to investigate the effects of DElncRNAs, DEmiRNAs, and DEmRNAs on overall survival. A total of 2,255 mRNAs, 133 miRNAs, and 150 lncRNAs that were differentially expressed were identified with a threshold of P<0.05 and |fold change (FC)|>2. Functional enrichment analysis indicated that DEmRNAs were enriched in cancer-associated KEGG pathways. Furthermore, 255 mRNAs, 15 miRNAs, and 12 lncRNAs that were significantly associated with overall survival in cervical carcinoma were also identified. Importantly, an miRNA-mediated competitive endogenous RNA (ceRNA) network was successfully constructed based on the expression profiles of DElncRNAs and DEmRNAs. More importantly, it was found that the lncRNA EPB41L4A-AS1 may function as a pivotal regulator in carcinoma of the uterine cervix. Taken together, the present study has provided novel insights into investigating the potential mechanisms underlying tumorigenesis, development, and prognosis of cervical cancer, and presented new potential avenues for cancer therapeutics. [ABSTRACT FROM AUTHOR]

Alcoholic liver disease (ALD), a liver function disorder caused by excessive alcohol intake, is a serious threat to global public health and social development. Toxic metabolites and reactive oxygen species produced during the metabolism of alcohol can alter the epigenetic state including DNA methylation, histone modifications, and expression of microRNAs. Epigenetic alterations can conversely involve various signaling pathways, which could contribute to the initiation and progression of ALD. To elucidate the relationship between epigenetic alterations and alcohol damage not only reinforces our understanding on pathogenesis of ALD, but also provides novel targets for clinical diagnosis, treatment, and drug research of ALD. In this review, we have summarized the research progress of epigenetic alterations and related mechanisms caused by alcohol in the pathogenesis of ALD. Considering the invertibility of epigenetic alterations, treatment of ALD through epigenetic modification with common less harmful compounds is also related. [ABSTRACT FROM AUTHOR]

Many studies have revealed that microRNAs (miRNAs) play crucial roles in cancer development and progression. miRNA-30a (miR-30a), as a member of the miR-30 family, has been implicated in various cancers. However, the role of miR-30a in osteosarcoma remains unclear. In the current study, we found that miR-30a was significantly downregulated in osteosarcoma tissues and cell lines by using quantitative real-time polymerase chain reaction (qRT-PCR). In addition, miR-30a could inhibit cancer cell growth, migration, and invasion in vitro. Furthermore, bioinformatics of miRNA target prediction and luciferase reporter assay indicated that MEF2D is a direct target of miR-30a. miR-30a was able to reduce the mRNA and protein expression of MEF2D as assessed using RT-PCR and Western blotting assay. Interestingly, overexpression of MEF2D partially reversed the miR-30a-reduced cell proliferation, migration, and invasion of osteosarcoma cell, indicating that miR-30a suppresses osteosarcoma cell proliferation and metastasis partially mediated by inhibition of MEF2D. Overall, our study demonstrated that miR-30a functions as a tumor suppressor by targeting MEF2D in osteosarcoma, providing a promising prognostic biomarker and a therapeutic strategy for osteosarcoma. [ABSTRACT FROM AUTHOR]

The interaction between tumors cells, tumor-derived humoral factors and the bone marrow in the bone niches has been shown to be essential for bone tumor initiation and promotion. Among the tumor stromal cells, tumor-associated macrophages (TAMs) are usually the most abundant immune population. Previously, we reported that let-7a functions as a tumor suppressor in ES. Herein, we found that the suppressive effects are not only limited on the malignant phenotype of tumor cells but also on the regulation of macrophage infiltration. We observed that the let-7a expression is negatively related to macrophage infiltrations in ES. Moreover, overexpression of putative ts-miRNA let-7a significantly suppressed the recruitment of PBMCs in vitro and decreased the macrophage infiltrations in ES-xenografted tumors in vivo. Most importantly, a positive regulatory feedback loop consisting of let-7a, signal transducer and activator of transcription 3 (STAT3), and nuclear factor-kappa B (NF-κB) (let-7a/STAT3/NF-κB) was involved in let-7a-mediated suppressive effects. These data might provide evidence of a novel intracellular signaling network function in ES pathogenesis, and manipulating this novel feedback loop will have therapeutic potential for ES patients. [ABSTRACT FROM AUTHOR]

An imbalance between T helper 1 (Th1) and T helper 2 (Th2) cells has been reported to increase plaque instability in patients with unstable angina (UA). MicroRNAs play a vital role in the differentiation of CD4+ T cells. However, the role of microRNAs in regulation of Th1/Th2 balance in UA remains unclear. In this study, we aimed to elucidate microRNA expression profiles of circulating CD4+ T cells in UA and to explore the function of microRNAs in the Th1/Th2 balance. A total of 53 patients with UA and 31 control subjects without coronary artery disease were enrolled. Microarray analysis of the microRNA expression profiles of CD4+ T cells revealed that miR-155 was the most significantly upregulated microRNA of the 451 differentially expressed microRNAs. The upregulation of miR-155 expression was positively correlated with the percentage of Th1 cells and interferon-gamma (IFN-γ) levels in patients with UA. In addition, overexpression of miR-155 in human circulating CD4+ T cells promoted Th1 differentiation. Further studies identified IFN-γ receptor alpha chain ( IFN-γ Rα) mRNA as a direct and functional target of miR-155. A luciferase reporter assay verified that miR-155 directly targeted IFN-γ Rα mRNA. Small-interfering RNA-mediated knockdown of IFN-γ Rα mRNA showed effects similar to those of ectopic miR-155 expression. Thus, our study indicated that upregulation of miR-155 in circulating CD4+ T cells in patients with UA promoted a shift in the Th1/Th2 balance toward Th1 dominance by repressing IFN-γ Rα, which may subsequently enhance plaque instability. J. Cell. Physiol. 230: 2498-2509, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

MicroRNAs play an important role in the development and progression of Ewing's sarcoma (ES). Especially, the expression of let-7a has been reported to be significantly downregulated in various cancers, and can affect the initiation and maintenance of tumor progression. However, the relative effects of let-7a on ES cells and relative mechanisms are largely unknown. In this study, we identified the underexpression of let-7a in human ES cells comparing with the human mesenchymal stem cells. Then, we sought to compensate for its loss through exogenous transfection with let-7a mimic into ES cell lines A673 and SK-ES-1. Restored let-7a expression inhibited cell proliferation, migration, as well as invasion; arrested cell cycle progression; and induced cell apoptosis of both cell lines. Moreover, bioinformatic prediction suggested that cyclin-dependent kinase 6 ( CDK6), which is overexpressed and functions as an oncoprotein in ES cells, is a putative target gene of let-7a. Using mRNA and protein expression analysis and luciferase assays, we further identified the target role of CDK6. Finally, we found that restored CDK6 expression in ES cells that had been treated with let-7a mimic before could partly dampen let-7a-mediated tumor suppression. Taken together, our results showed that let-7a acted as a tumor suppressor in ES by targeting CDK6, and it may provide novel diagnostic and therapeutic options for human Ewing sarcoma clinical operation in future. [ABSTRACT FROM AUTHOR]

Aims Mcl-1, an antiapoptotic member of the Bcl-2 family, is overexpressed in human glioblastoma, conferring a survival advantage to tumor cells. The mechanisms underlying its dysregulation have not been clarified. In this study, we explored the involvement of micro-RNAs that acted as endogenous sequence-specific suppressors of gene expression. Methods and results Using computational and TCGA analysis, we identified miR-139 as being downregulated in glioblastoma in comparison with human brain tissue, as well as possessing a putative target site in Mcl-1 m RNA. Overexpression of miR-139 led to a clear decrease in Mcl-1 expression in gliomas. Reporter assays revealed direct post-transcriptional regulation involving miR-139 and the 3′-untranslated region of Mcl-1. Human glioma tissues with low expression of miR-139 displayed higher expression of Mcl-1 protein than those with high expression, suggesting that low miR-139 contributes to Mcl-1 overexpression. In addition, upregulation of miR-139 suppressed the proliferation and enhanced temozolomide ( TMZ)-induced apoptosis. Finally, we observed that Mcl-1 knockdown resulted in similar effects compared with miR-139 transfection. Conclusion Our results suggested that miR-139 negatively regulated Mcl-1 and induced apoptosis in cooperation with an anticancer drug TMZ in glioma. [ABSTRACT FROM AUTHOR]

Abstract: MicroRNAs (miRNAs) are endogenous small noncoding RNA molecules that suppress gene expression via degradation or translational inhibition of their target genes. Many miRNAs are associated with cardiac hypertrophy and heart failure. In this study, we pursued to identify miRNAs that negatively regulate cardiac hypertrophy by utilizing a surgical model for regression of cardiac hypertrophy. Microarray analysis revealed that 15 miRNAs out of the 696 miRNAs tested were specifically up-regulated during the regression period. Among these regression-specific miRNAs, nine microRNAs, which have not been previously reported, were further tested for their effects on phenylephrine (PE)-treated neonatal cardiomyocytes. Consequently, five miRNAs (miR-101b, 142-3p, 181d, 24-2∗, and 450a) completely abrogated PE-induced hypertrophy as determined by measurements of cell size and fetal gene expression. Conversely, antagomers of these miRNAs exacerbated the PE-induced hypertrophy. Collectively, these findings suggest that the five miRNAs newly identified by using our cardiac hypertrophy-regression surgical model negatively regulate cardiac hypertrophy and could be used as potential therapeutic targets for the treatment of heart diseases. [Copyright &y& Elsevier]