miR-124 promotes proliferation and differentiation of neuronal stem cells through inactivating Notch pathway

Background

Neural stem cells (NSCs) are able to differentiate into neurons and astroglia. miRNAs have been demonstrated to be involved in NSC self-renewal, proliferation and differentiation. However, the exact role of miR-124 in the development of NSCs and its underlying mechanism remain to be explored.

Methods

Primary NSCs were isolated from embryos of Wistar rats. Immunocytochemistry was used to stain purified NSCs. miR-124, Delta-like 4 (DLL4), ki-67, Nestin, β-tubulin III, glial fibrillary acidic protein (GFAP), HES1, HEY2, and cyclin D1 (CCND1) expressions were detected by qRT-PCR and western blot. The interaction between miR-124 and DLL4 was confirmed by luciferase reporter assay. Cell proliferation was assessed by MTT assay.

Results

NSCs could self-proliferate and differentiate into neurons and astrocyte. miR-124 was up-regulated and DLL4 was down-regulated during NSC differentiation. DLL4 was identified as a target of miR-124 in NSCs. Ectopic expression of miR-124 or knockdown of DLL4 promoted the proliferation and the formation of NSCs to neurospheres. Moreover, miR-124 overexpression or DLL4 down-regulation improved β-tubulin III expression but decreased GFAP expression in NSCs. Furthermore, enforced expression of DLL4 partially reversed the effects of miR-124 on NSCs proliferation and differentiation. Elevated expression of miR-124 suppressed the expressions of HES1, HEY2, and CCND1 in NSCs, while these effects were attenuated following the enhancement of DLL4 expression.

Conclusion

miR-124 promoted proliferation and differentiation of NSCs through inactivating Notch pathway.

     

Evaluation of miR-21 and miR-150 expression in immune thrombocytopenic purpura pathogenesis: a case-control study

Background

Immune thrombocytopenic purpura (ITP) is a common autoimmune disorder diagnosed with thrombocytopenia and bleeding symptoms due to production of autoantibodies (Abs) against platelets. Nowadays, microRNAs are known as novel biomarkers for diagnosis of diseases. The aim of this study was to investigate the expression levels of miR-21 and miR-150 in ITP patients and determine the role of these miRNAs in ITP pathogenesis.

Materials and Methods

Thirty newly diagnosed patients with acute ITP and 30 healthy subjects( age and sex matched) as controls were enrolled in this study. The expression level of miR-21 and miR-150 was investigated using Real-time-PCR. Comparison of demographic characteristics of the cases was done using independent t-test and chi-square test. Comparison of the expression level of miR-21 and miR-150 with the related parameters was done using independent t-test or Mann–Whitney and Kruskal–Wallis test. Spearman rho correlation coefficient was used to investigate the relationship between the expression of miR-21 and miR-150 with demographic characteristics.

Results

The expression of miR-21, 150 in the patients was not different compared with the control group in general. A significant relationship between the expression of miR-21 with hemoglobin, hematocrit and red blood cell hemoglobin concentration was observed.

Discussion

Expression of miR-21 and miR-150 is not associated with pathogenesis of acute ITP and can involve the synergistic role of other miRNAs. Investigation of miR-21 and miR-150 expression along with other miRNAs and cytokines can be helpful in diagnosis and pathogenesis of ITP.

     

miR-34a attenuates glioma cells progression and chemoresistance via targeting PD-L1

Objective

To investigate the roles of miR-34a in progression and chemoresistance of glioma cells.

Results

Quantitative real-time PCR analysis showed that miR-34a level was lower, but PD-L1 expression level was higher in glioma tissue specimens compared with normal brain tissues and their expression levels were negatively correlated. Ectopic expression of miR-34a inhibited glioma cell proliferation, promoted cell cycle arrest in G1/S phase and cell apoptosis. Additionally, miR-34a/PD-L1 axis was again confirmed and co-expression of PD-L1 with miR-34a mimics attenuated the effects of miR-34a on cell proliferation and apoptosis in glioma cells. Importantly, PD-L1 overexpression resulted in chemoresistance in glioma cells, this effect was attenuated by miR-34a overexpression.

Conclusions

miR-34a inhibits glioma cells progression and chemoresistance via targeting PD-L1.

     

HuR facilitates cancer stemness of lung cancer cells via regulating miR-873/CDK3 and miR-125a-3p/CDK3 axis

Objectives

To study the roles and mechanisms of HuR in cancer stem cell maintenance of lung cancer.

Results

HuR expression was increased in tumor spheres of lung cancer cells. Knockdown of HuR suppressed spheroid formation and size, inhibited the expression of stemness-related marker, Oct4, Nanog and ALDH in lung cancer cells. Importantly, HuR and CDK3 expressions were increased in lung cancer tissues compared with normal adjacent tissues, and positively correlated. Mechanistically, HuR directly bound to CDK3, and increased CDK3 mRNA stability and expression. Additionally, miR-873 or miR-125a-3p attenuated the promotion of HuR on CDK3 expression and lung cancer stemness. Furthermore, HuR facilitated lung cancer stemness dependent on CDK3 expression. miR-873 or miR-125a-3p level was negatively correlated with HuR and CDK3 expression levels in lung cancer tissues.

Conclusions

HuR facilitates lung cancer stemness via regulating miR-873/CDK3 and miR-125a-3p/CDK3 axis.

     

MicroRNA-4728 serves as a suppressor and antagonist of oncogenic MAPK in Burkitt lymphoma

Objective

This study identified the biological role of miR-4728 in Burkitt lymphoma (BL) process.

Non-small cell lung cancer: miR-30d suppresses tumor invasion and migration by directly targeting NFIB

Objective

To evaluate the role and the molecular mechanism of miR-30d in non-small cell lung cancer (NSCLC).

Results

qRT-PCR was used to detect miR-30d expression in NSCLC tissues and cell lines. miR-30d was frequently down-regulated in NSCLC and its expression was associated with clinicopathological features of NSCLCC patients. Over-expression of miR-30d notably inhibited cell migration and invasion in NSCLC cell lines. miR-30d could negatively regulate Nuclear factor I B (NFIB) by directly targeting its 3′-UTR, which was confirmed by luciferase assay. NFIB also reversed miR-30d-mediated suppression on the migration and invasion in NSCLC cell lines.

Conclusion

miR-30d suppressed cell migration and invasion by directly targeting NFIB in NSCLC, and NFIB could partially abrogated the inhibition of biological functions by miR-30d.

     

miR-215 functions as an oncogene in high-grade glioma by regulating retinoblastoma 1

Objectives

To investigate the roles of miR-215 in high-grade glioma and to clarify the regulation of retinoblastoma 1 (RB1) by miR-215.

Results

miR-215 is frequently up-regulated in high-grade glioma tissues. Increased miR-215 expression is significantly associated with World Health Organization grade (P < 0.01) tumor size (P < 0.05) and poor prognosis (P < 0.01). Over-expression of miR-215 promoted cell proliferation and knockdown of miR-215 inhibited cell proliferation in vitro. RB1 was identified as a direct and functional target of miR-215. RB1 is generally down-regulated in glioma tissues and its expression inversely correlated with miR-215, which is up-regulated in high-grade glioma tissues, and its expression was negatively correlated with miR-215.

Conclusions

The new miR-215/RB1 axis provides new insights into the molecular mechanism and treatment for glioma.

     

Role of morphine,miR-212/132 and mu opioid receptor in the regulation of Bdnf in zebrafish embryos

BackgroundMorphine is one of the first-line therapies for the treatment of pain despite its secondary effects. It modifies the expression of epigenetic factors like miRNAs. In the present study, we analyzed miR-212 and miR-132 and their implication in morphine effects in the zebrafish Central Nervous System (CNS) through the regulation of Bdnf expression.MethodsWe used control and knock-down zebrafish embryos to assess the effects of morphine in miRNAs 212/132 and mitotic or apoptotic cells by qPCR, immunohistochemistry and TUNEL assay, respectively. Bdnf and TrkB were studied by western blot and through a primary neuron culture. A luciferase assay was performed to confirm the binding of miRNAs 212/132 to mecp2.ResultsMorphine exposure decreases miR-212 but upregulates miR-132, as wells as Bdnf and TrkB, and changes the localization of proliferative cells. However, Bdnf expression was downregulated when miRNAs 212/132 and oprm1 were knocked-down. Furthermore, we proved that these miRNAs inhibit mecp2 expression by binding to its mRNA sequence. The described effects were corroborated in a primary neuron culture from zebrafish embryos.ConclusionsWe propose a mechanism in which morphine alters the levels of miRNAs 212/132 increasing Bdnf expression through mecp2 inhibition. oprm1 is also directly involved in this regulation. The present work confirms a relationship between the opioid system and neurotrophins and shows a key role of miR-212 and miR-132 on morphine effects through the regulation of Bdnf pathway.General significance.miRNAs 212/132 are novel regulators of morphine effects on CNS. Oprm1 controls the normal expression of Bdnf.     

miR-93 enhances hepatocellular carcinoma invasion and metastasis by EMT via targeting PDCD4

Objectives

To clarify the potential biological function of miR-93 and its related molecular mechanism underlying metastasis in human hepatocellular carcinoma (HCC).

Results

miR-93 was significantly up-regulated in HCC tissues and was associated with poor 5-year overall survival in HCC patients. Transwell assays showed that over-expression of miR-93 increased HCC cell migration and invasion in vitro. Programmed cell death 4 (PDCD4) was a target gene of miR-93 and miR-93 could down-regulate the expression of PDCD4 by directly targeting its 3′-UTR. The re-expression of PDCD4 could attenuate the HCC cell invasion and migration induced by miR-93, while the knockdown of PDCD4 would promote HCC cell migration and invasion via the epithelial-mesenchymal transition (EMT) pathway.

Conclusions

miR-93 provides new insight into the molecular mechanisms of pathogenesis and progression in HCC and offer a potential therapeutic target for the treatment of HCC patients.

     

Memory retrieval in addiction: a role for miR-105-mediated regulation of D1 receptors in mPFC neurons projecting to the basolateral amygdala

Background

Drug addiction is a chronic brain disorder characterized by the compulsive use of drugs. The study of chronic morphine-induced adaptation in the brain and its functional significance is of importance to understand the mechanism of morphine addiction. Previous studies have found a number of chronic morphine-induced adaptive changes at molecular levels in the brain. A study from our lab showed that chronic morphine-induced increases in the expression of D1 receptors at presynaptic terminals coming from other structures to the basolateral amygdala (BLA) played an important role in environmental cue-induced retrieval of morphine withdrawal memory. However, the neurocircuitry where the increased D1 receptors are located and how chronic morphine increases D1 receptor expression in specific neurocircuits remain to be elucidated.

Results

Our results show that chronic morphine induces a persistent increase in D1 receptor expression in glutamatergic terminals of projection neurons from the medial prefrontal cortex (mPFC) to the BLA, but has no influence on D1 receptor expression in projection neurons from the hippocampus or the thalamus to the BLA. This adaptation to chronic morphine is mediated by reduced expression of miR-105 in the mPFC, which results in enhanced D1 receptor expression in glutamatergic terminals of projection neurons from the mPFC to the BLA. Ex vivo optogenetic experiments show that a chronic morphine-induced increase in D1 receptor expression in glutamatergic terminals of projection neurons from the mPFC to the BLA results in sensitization of the effect of D1 receptor agonist on presynaptic glutamate release. mPFC to BLA projection neurons are activated by withdrawal-associated environmental cues in morphine-withdrawal rats, and overexpression of miR-105 in the mPFC leads to reduced D1 receptor induction in response to chronic morphine in glutamatergic terminals of the projection neurons from the mPFC to the BLA, and a reduction in place aversion conditioned by morphine withdrawal.

Conclusions

These results suggest that chronic morphine use induces a persistent increase in D1 receptors in glutamatergic terminals of projection neurons from the mPFC to the BLA via downregulation of miR-105 in the mPFC, and that these adaptive changes contribute to environmental cue-induced retrieval of morphine withdrawal memory.

     

miR-149 promotes human osteocarcinoma progression via targeting bone morphogenetic protein 9 (BMP9)

Objectives

To investigate the roles of miR-149 in the progression of human osteosarcoma (OS).

Results

miR-149 level was upregulated in tissues from OS patients more than in normal subjects. Cell proliferation and apoptosis assays revealed that miR-149 increased cell proliferation and inhibited cell apoptosis in OS cell line (MG63). An increase of Bcl-2 gene expression and a decrease of cleaved-caspase-3, and cleaved-PARP expression were observed in MG63 cells with transfection of miR-149. Additionally, bone morphogenetic protein 9 (BMP9) was identified as a target of miR-149 in MG63 cells, and BMP9 expression was negatively correlated with miR149 level in OS clinical samples. Co-overexpression of BMP9 with miR-149 in MG63 cells prohibited miR-149-mediated promotive effects on OS progression. Importantly, overexpression of miR-149 conferred chemoresistance in MG63 cells.

Conclusions

miR-149 promotes OS progression via targeting BMP9.

     

microRNA-1297 involves in the progression of oral squamous cell carcinoma through PTEN

Background

Oral squamous cell carcinoma (OSCC) oncogenic mechanisms still remain elusive. Herein, we proposed to understand the biological role of a newly discovered OSCC miRNA.

miR-130b-3p/301b-3p negatively regulated Rb1cc1 expression on myogenic differentiation of chicken primary myoblasts

Objectives

To explore the roles of miR-130b-3p and miR-301b-3p which may regulate Rb1-inducible coiled-coil 1 (Rb1cc1) expression during myogenic differentiation of chicken primary myoblasts.

Results

After 4 days of myogenic differentiation, myotubes appeared and after 6 days the cells fused to each other and expression of MyHC could be detected by immunofluorescence staining. TargetScan and RNAhybrid 2.2 showed miR-130b-3p and miR-301b-3p were well complementary with the target site of Rb1cc1 3′-untranslated region (3′-UTR). Using the dual-luciferase assay, we found miR-130b-3p and miR-301b-3p could inhibit Rb1cc1 expression by binding to its 3′-UTR. Real-time PCR showed Rb1cc1 mRNA expression level was almost reciprocal to that of miR-130b-3p or miR-301b-3p during myogenic differentiation. Furthermore, over-expression of miR-130b-3p or miR-301b-3p down-regulated the expression levels of Rb1cc1, myoblast determination protein, myogenin and myosin heavy chain.

Conclusions

miR-130b-3p or miR-301b-3p negatively regulate Rb1cc1 expression to affect myogenic differentiation.

     

The lncRNA MEG3 downregulation leads to osteoarthritis progression via miR-16/SMAD7 axis

Background

Osteoarthritis (OA) is a chronic joint disease and there is no a definitive cure at present. Long non-coding RNAs (lncRNAs) have been confirmed to play important roles in the development of OA. However, the underlying mechanism of lncRNA maternally expressed gene 3 (MEG3) in OA has not been well elucidated.

Methods

The rat OA model and interleukin-1β (IL-1β)-induced rat chondrocytes were constructed. The expression pattern of lncRNA MEG3 and miR-16 was detected by RT-qPCR assay in cartilage tissues of rat OA model. The effect of MEG3 and miR-16 on IL-1β-induced chondrocytes was evaluated on the basis of cell viability and apoptosis. Then, the interaction among MEG3, miR-16 SMAD7 was explored by dual-luciferase reporter assay and RIP assay.

Results

It is found that lncRNA MEG3 was down-regulated and miR-16 was up-regulated in rat OA cartilage tissues. MEG3 knockdown promoted proliferation and inhibited apoptosis, while miR-16 knockdown suppressed proliferation and promoted apoptosis in IL-1β-induced rat chondrocytes. Moreover, MEG3 was involved in miR-16 pathway and MEG3 suppressed miR-16 expression. Additionally, SMAD7 was a target gene of miR-16 and miR-16 suppressed SMAD7 expression in IL-1β-induced chondrocytes. Moreover, the expression of SMAD7 induced by MEG3 or si-MEG3 was markedly reversed by the introduction of miR-16 or anti-miR-16. Furthermore, MEG3 exerted its anti-proliferation and pro-apoptosis by regulating miR-16 and SMAD7.

Conclusion

MEG3 was down-regulated and miR-16 was up-regulated in cartilage tissues of rat OA model. MEG3 knockdown might lead to the progression of OA through miR-16/SMAD7 axis.

     

Bioinformatics prediction of miR-30a targets and its inhibition of cell proliferation of osteosarcoma by up-regulating the expression of PTEN

Background

MiRNAs are frequently abnormally expressed in the progression of human osteosarcoma. Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is one of the tumor suppressors in various types of human cancer. In the present study, we detected how hsa-miR-30a-3p regulated PTEN and further tested the role of hsa-miR-30a-3p in the cell proliferation of osteosarcoma cells.

Methods

The levels of miR-30a were determined by real time PCR. The expression of PTEN was tested by western blotting analysis. Cell distribution of PTEN was observed with confocal laser scanning microscope. Cell viability was determined by MTT assay.

Results

The expression of miR-30a and PTEN was obviously decreased in MG-63, 143B and Saos-2 cells compared with primary osteoblasts. TargetScan analysis data showed miR-30a might bind with position 30-57 of 3’UTR of PTEN. Transfection with miR-30a-3p increased the level of PTEN in MG-63 cells, while transfection with miR-30a-3p inhibitor significantly decreased the expression of PTEN in osteosarcoma cells. Transfection with miR-30a-3p significantly inhibited cell proliferation of osteosarcoma cells, while miR-30a inhibitor obviously promoted cell viability of MG63 cells and Saos-2 cells. Inhibition of PTEN eliminated the proliferation inhibitory effect of miR-30a-3p.

Conclusion

Thus, all these findings revealed the anti-tumor effects of miR-30a in human osteosarcoma cells, which could be mediated by regulating the level of PTEN.

     

miR-1260b promotes cell migration and invasion of hepatocellular carcinoma by targeting the regulator of G-protein signaling 22

Objectives

To investigate whether miR-1260b can regulate migration and invasion of hepatocellular carcinoma (HCC) by targeting RGS22.

Results

miR-1260b was up-regulated in HCC tissues compared with their corresponding non-cancerous tissues. Over-expression of miR-1260b increased migration and invasion of HepG2 and SMMC-7721 cells associated with HCC. Regulator of G-protein signaling 22 (RGS22) was identified as a directly target of miR-1260b and was inhibited by miR-1260b. Knockdown of RGS22 increased proliferation of HCC cells.

Conclusions

The new identified miR-1260b/RGS22 axis provides useful therapeutic methods for treatment of HCC deepening on our understanding of underlying mechanisms of HCC tumorigenesis.