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Exosomes play a crucial role in regulating crosstalk between tumor and tumor stem-like cells through their cargo molecules. Circular RNAs (circRNAs) have recently been demonstrated to be critical factors in tumorigenesis. This study focuses on the molecular mechanism by which circRNAs from glioma stem-like cell (GSLC) exosomes regulate glioblastoma (GBM) tumorigenicity. In this study, we validated that GSLC exosomes accelerated the malignant phenotype of GBM. Subsequently, we found that circZNF800 was highly expressed in GSLC exosomes and was negatively associated with GBM patients. CircZNF800 promoted GBM cell proliferation and migration and inhibited GBM cell apoptosis in vitro. Silencing circZNF800 could improve the GBM xenograft model survival rate. Mechanistic studies revealed that circZNF800 activated the PIEZO1/Akt signaling pathway by sponging miR-139-5p. CircZNF800 derived from GSLC exosomes promoted GBM cell tumorigenicity and predicted poor prognosis in GBM patients. CircZNF800 has the potential to serve as a promising target for further therapeutic exploration. [ABSTRACT FROM AUTHOR]

Summary: Background: Esophageal squamous cell carcinoma (ESCC) is the most prevalent histological subtype of esophageal cancer. miR-139-5p has been shown to have abnormal expression in ESCC. We intend to probe into the roles of miR-139-5p in ESCC, thus providing references for investigating underlying therapeutic targets. Methods: miR-139-5p expression in esophageal carcinoma was predicted by the Starbase online website. miR-139-5p expression in human ESCC cell lines (KYSE-150, KYSE-410, KSE-30) and human esophageal epithelial cell line Het1A was determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR). KYSE-150 cells were manipulated with miR-139-5p mimic to upregulate miR-139-5p. Cell colony formation, viability, apoptosis, migration, and invasion were assessed by colony formation assay, CCK‑8, flow cytometry, wound healing test, and Transwell. The targeted binding between miR-139-5p and TGIF1 was predicted on Starbase, Targetscan, and miRDB online websites and verified by Dual-Luciferase assay. Cells were transfected with miR-139-5p mimic and pcDNA3.1 TGIF1. The phosphorylation levels of TGFβ pathway-related proteins Smad2 and Smad3 were assessed by RT-qPCR and western blot. Results: miR-139-5p was underexpressed in ESCC cells. miR-139-5p overexpression reduced ESCC cell viability, migration, and invasion, and promoted apoptosis. TGIF1 overexpression averted miR-139-5p mimic-inhibited ESCC cell growth. miR-139-5p overexpression decreased the phosphorylation levels of TGFβ pathway-related proteins Smad2 and Smad3, while the phosphorylation levels were increased by additional TGIF1 vector transfection. Conclusion: miR-139-5p mediates TGIF1 to regulate TGFβ pathway and inhibit ESCC cell growth. [ABSTRACT FROM AUTHOR]

This study aims to investigate the specific mechanism of miR-139-5p regulating hepatocellular carcinoma (HCC). Bioinformatic approaches was utilized to observe miR-139-5p level in HCC and unearth its target mRNA. Next, miR-139-5p and enabled homolog (ENAH) levels in HCC cell lines and normal liver cell line were evaluated with qRT-PCR. ENAH protein level was assessed by Western blot. The cell viability, migratory and invasive capacities of HepG2 cells was observed by cell functional assays. The binding of these two genes was proved through dual-luciferase method. Xenograft nude mouse model was prepared to identify the role of miR-139-5p in vivo. Poorly expressed miR-139-5p in HCC hindered the phenotypes of cancer cells. ENAH was at high level in HCC and it is a downstream target of miR-139-5p. Additionally, ENAH could reverse the suppressive impacts of miR-139-5p on HCC cell behaviors. Likewise, miR-139-5p was determined to perform tumor-suppressing function in vivo. MiR-139-5p hampered HCC cell processes by mediating ENAH, and miR-139-5p/ENAH is hopefully to be the possible target for HCC patients. [ABSTRACT FROM AUTHOR]

Lung adenocarcinoma (LUAD) is the most frequent histological subtype of non-small cell lung cancer. Cyclin B1 (CCNB1) is the vital initiator and controller of mitosis. Studies have indicated that CCNB1 overexpression is closely associated with cell proliferation and tumorigenesis in many cancers. Thus, discovery of molecular mechanism of CCNB1 in LUAD is conducive to developing new diagnostic or therapeutic targets for LUAD. We acquired mature miRNA and mRNA expression information of LUAD from TCGA database, as well as related clinical data. CCNB1 expression in normal and LUAD tissue was analyzed. Relationship between CCNB1 and patient's survival and clinical stage was analyzed. Upstream regulatory gene miRNA of CCNB1 was predicted. qRT-PCR and western blot examined expression levels of CCNB1 and miR-139-5p in cells. CCK-8 tested cell proliferation. Scratch healing and Transwell determined cell migration and invasion. Flow cytometry analyzed the cell cycle. Dual-luciferase verified targeting relationship between the two genes. Compared to controls, CCNB1 expression was prominently high in LUAD patient samples, and associated with advanced tumor stages and shorter overall survival. MiR-139-5p expressed an evidently negative correlation with CCNB1 and was predicted to target CCNB1. MiR-139-5p mimics reduced CCNB1 mRNA and protein expression, and suppressed luciferase activity in a target-specific manner, as confirmed by a control construct with a mutated miR-139-5p binding site. CCNB1 overexpression fostered progression of LUAD cells. Mechanistically, miR-139-5p might negatively regulate CCNB1 in LUAD, thereby suppressing cell proliferation, migration, invasion and cell cycle. [ABSTRACT FROM AUTHOR]

Pathological retinal neovascularization is a driver of the progression of diabetic retinopathy (DR). The present study sought to identify the microRNAs (miRNAs) that are differentially expressed during the progression of DR as well as to explore the specific regulatory mechanism of those miRNAs in retinal neovascularization. Using a microarray data set and a diabetic mouse model, it was determined that miR-139-5p was significantly upregulated during the progression of DR. The in vitro investigation revealed an elevation in the miR-139-5p level in both the high glucose (HG)-treated mouse retinal microvascular endothelial cells (mRMECs) and the HG-treated human RMECs (hRMECs). The miR-139-5p overexpression elevated cell migration, facilitated tube formation, and increased vascular endothelial growth factor (VEGF) protein level in the hRMECs. While the angiogenic effect of miR-139-5p overexpression was halted by an anti-VEGF antibody. Meanwhile, the miR-139-5p knockdown eliminated the VEGF-induced cell migration and tube formation in the hRMECs. The phosphatase and tensin homolog (PTEN) was the target gene of the miR-139-5p. PTEN overexpression removed the angiogenic effect of miR-139-5p overexpression, which led to reduced cell migration and tube formation. In the diabetic mice, the miR-139-5p antagomir effectively decreased the acellular capillaries and suppressed the formation of aberrant blood vessels in the retinal tissues. Taken together, miR-139-5p promotes retinal neovascularization by repressing PTEN expression. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) are proved to perform critical function in regulating cancer cell behavior. It is reported that LINC00324 promotes lung adenocarcinoma development by regulating miR-615-5p/AKT1 axis. This study aimed to demonstrate whether LINC00324 participates in non-small cell lung cancer (NSCLC) pathogenesis through other molecular mechanism. Relative mRNA, lncRNA, and microRNA levels were analyzed using quantitative real-time–polymerase chain reaction (qRT-PCR). Western blot was used to detect protein level. MTT assay shown proliferation ability and transwell assay shown invasive ability. Luciferase reporter assay illustrated the interaction between RNA molecules. In NSCLC, the high expression of LINC00324 had correlation with the poor prognosis. LINC00324 promoted the proliferation and invasion of NSCLC cells while miR-139-5p inhibited these behaviors. LINC00324 overexpression promoted insulin-like growth factor 1 receptor (IGF1R) expression via absorbing miR-139-5p. The tumor-promoting effects of LINC00324 were attenuated through miR-139-5p overexpression. Highly expressed LINC00324 in NSCLC through sponged miR-139-5p to elevate IGF1R expression and promoted cell proliferation and invasion. This research demonstrated that LINC00324 is a potential NSCLC diagnosis and therapy target. [ABSTRACT FROM AUTHOR]

Non-small-cell lung cancer (NSCLC) is a complex disease which is influenced by multiple factors. Recent studies demonstrated that long non-coding RNA (lncRNA) MIAT was involved in tumor metastasis. However, the underlying mechanism of MIAT in NSCLC remains largely unknown. In this study, MIAT, miR-139-5p and MMP2 expression were measured by quantitative reverse transcriptase PCR (QRT-PCR) or Western blotting, respectively, and we found the expression of MIAT and MMP2 were elevated, while miR-139-5p was decreased in NSCLC tissues and cell lines. Transwell assay showed MIAT and MMP2 functioned as an oncogene to induce cell migration and invasion in NSCLC, but miR-139-5p served as a tumor suppressor in NSCLC to inhibit cell migration and invasion. Besides that, in vivo experiments also indicated MIAT deletion inhibited tumor growth. The relationship between miR-139-5p and MIAT or MMP2 was then confirmed by Luciferase reporter assay, and the results showed that MIAT directly interacted with miR-139-5p and miR-139-5p targetedly suppressed MMP2 in NSCLC cells. Furthermore, expression analysis showed that MIAT indirectly regulated MMP2 by sponging miR-139-5p. Finally, rescue assay suggested that miR-139-5p restoration reversed MIAT-overexpression-induced promotion on the migration and invasion of NSCLC cells. In conclusion, our results demonstrated that lncRNA MIAT modulated the migration and invasion of NSCLC by regulating miR-139-5p and MMP2. [ABSTRACT FROM AUTHOR]

Chronic exposure to morphine can produce tolerance, dependence and addiction, but the underlying neurobiological basis is still incompletely understood. c-Jun, as an important component of the activator protein-1 transcription factor, is supposed to take part in regulating gene expression in AC/cAMP/PKA signaling. MicroRNA (miRNA) has emerged as a critical regulator of neuronal functions. Although a number of miRNAs have been reported to regulate the μ-opioid receptor expression, there has been no report about miRNAs to regulate chronic morphine-induced, naloxone-precipitated cAMP overshoot. Our results showed that chronic morphine pretreatment induced naloxone-precipitated cAMP overshoot in concentration- and time-dependent manners in HEK 293/μ cells. Chronic morphine pretreatment alone elevated both c-Jun protein and miR-139-5p expression levels, while dramatically artificial elevation of miR-139-5p inhibited c-Jun at the translational level. Furthermore, dramatically artificial upregulation of intracellular miR-139-5p limited chronic morphine-induced, naloxone-precipitated cAMP overshoot. These findings suggested that miR-139-5p was involved in regulating chronic morphine-induced, naloxone-precipitated cAMP overshoot in a negative feedback manner through its target c-Jun, which extends our understanding of neurobiological mechanisms underlying morphine dependence and addiction. [ABSTRACT FROM AUTHOR]

The aim of our study is to identify microRNAs (miRNAs) that have significance in the prognosis and pathogenesis of hepatocellular carcinoma (HCC). The miRNAs differentially expressed in HCC were examined by using a human miRNA microarray dataset, and then the acquired candidates were screened by another microarray dataset. As a result, we got 25 miRNAs which were aberrantly expressed in cancer and meanwhile predicated distinct prognosis. Among them, miR-139-5p was down-regulated in HCC and its low expression in cancer tissue meant poor prognosis. Additionally, we demonstrated that its low expression was also related to several clinicopathologic characteristics such as vein invasion, BCLC stage, p-AKT expression, and pIGFR1 expression. In vitro, it has been discovered that treatment of HCC cells with a miR-139-5p mimic lead to inhibition of cell growth and migration. Moreover, luciferase assay showed that KPNA4 was not the direct target of miR-139-5p. Ectopic expression of miR-139-5p has not repressed the expression of KPNA4, but inhibited the nuclear import of NF-κB and phosphorylation of Akt. In conclusion, for the first time, we identify 25 deregulated miRNAs that are associated with prognosis and prove that miR-139-5p functions as a tumor suppressor in HCC and its low expression predicts poor prognosis. [ABSTRACT FROM AUTHOR]

Invasion and migration of glioblastoma multiforme (GBM) is a multistep process and an important phenotype that causes this disease to invade surrounding tissues in the brain. Recent studies have highlighted that miRNAs play a pivotal role in controlling GBM cell plasticity. In this report, we used wound healing and transwell assays to identify a novel role of miR-139-5p in inhibition of GBM cell migration and invasion. Bioinformatics coupled with luciferase and Western blot assays also revealed that miR-139-5p inhibited expression of ZEB1 and ZEB2, which are master regulators of tumor metastasis. MiR-139-5p specifically interacts with the 3′-UTR regions of ZEB1 and ZEB2, attenuating their expression in GBM cells. To corroborate this finding, we rescued ZEB1 and ZEB2 expression and found partial but significant increases in miR-139-5p-suppressed invasion of GBM cells. The biological relevance of our study was validated by analyzing levels of miR-139-5p in GBM tissue. We found that its expression significantly downregulated compared to normal tissue and shorter overall survival rates in patients with lower miR-139-5p expression. These results confirm that miR-139-5p suppresses GBM migration and invasion and highlight its potential as a biomarker and therapeutic target for treating GBM. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) were reported to be associated with cancer progression and carcinogenesis. MiRNAs are small, highly conserved, small non-coding RNA molecules, consisting of 18-25 nucleotides that control gene expression at the post-transcription level. By binding to complementary binding sites within the 3′ untranslated region (3′UTR) of target messenger RNAs (mRNAs), inhibiting translation or promoting degradation of mRNAs. MicroRNAs not only play an important part in regulating gene expression but also controlling diverse physiological and pathological processes. Similarly, several studies have demonstrated that miRNAs have been involved in regulating various biological processes, including apoptosis, proliferation, cellular differentiation, metabolism, signal transduction, and carcinogenesis. MiRNA-139, which is located in 11q13.4 and has anti-oncogenic and antimetastatic activity in humans, meanwhile, was identified to be downregulated in previous studies. However, based on the pathogenetic relationship between cancer and the role of miR-139-5p in tumorigenesis, we consider that miR-139-5p may be the candidates to serve as promising biomarkers with sufficient sensitivity and specificity for the diagnosis of cancer in a clinical setting; moreover, it would offer a new safe and effective way in further molecular targeting cancer treatment, as well as improving overall survival of patients. [ABSTRACT FROM AUTHOR]