Target Gene Of miR-132 Research Articles

RETRACTED: Long non-coding RNA LINC00160 functions as a decoy of microRNA-132 to mediate autophagy and drug resistance in hepatocellular carcinoma via inhibition of PIK3R3.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors. Following the publication of the above article, the authors found that “LINC00160 did not affect Atg5 and P65 protein expression in HCC cells, which was inconsistent with the result of this paper. Furthermore, we apologize to the readership of the Journal for any inconvenience caused.” Additionally, after publication, the journal was made aware of comments in relation to this article (https://pubpeer.com/publications/333AE65483683ADF50A723BE34AD62). The authors have not responded to our request to respond to these comments.

MicroRNA-132 promotes neurons cell apoptosis and activates Tau phosphorylation by targeting GTDC-1 in Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder with limited success in the prognosis of patients worldwide. The microRNA (miRNA) technology shows an encouraging trend in the therapeutics of AD. The study aimed to investigate the role of miR-132 and its underlying mechanism involving neuronal apoptosis and Tau phosphorylation in the pathophysiology of AD. Frozen human postmortem brain samples and neurons cells were used as the specimens. The expression of miR-132 was assessed in AD and mild-cognitive (MCI) group by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Then, miR-132 mimic, ASO-miR-132, and corresponding controls were transfected into necrotic cells. Flow cytometry was used to detected cell apoptosis in necrotic cells. qRT-PCR, Western blot, and immunoprecipitation were used to quantify and identify apoptosis-related factors (Bax and Bcl-2), Tau phosphorylation, CDK-5, GTDC-1 levels in necrotic cells. Furthermore, Dual-Luciferase reporter assay was used to predict a direct target of miR-132. The expression of miR-132 was significantly higher in patients with MCI and AD compared to the normal group. Overexpression of miR-132 induced neuronal apoptosis by increasing Bax and decreasing Bcl-2 and also up-regulated phosphorylation of Tau, Rb, Histone H1, and CDK-5 expressions. Besides, GTDC-1 was identified as a direct target gene of miR-132. However, GTDC-1 markedly reversed the promoting effect of miR-132 on cell apoptosis and Tau phosphorylation. MiR-132 plays an important role in the pathogenesis of AD via regulation of cell apoptosis and GTDC-1/CDK-5/Tau phosphorylation signaling mechanism. It may be a potential therapeutic target in patients with AD.

Pituitary Adenylate Cyclase-Activating Polypeptide Modulates Dendritic Spine Maturation and Morphogenesis via MicroRNA-132 Upregulation.

Alterations in pituitary adenylate cyclase-activating polypeptide (PACAP), a multifunctional neuropeptide, and its receptors have been identified as risk factors for certain psychiatric disorders, including schizophrenia. Increasing evidence from human genetic and animal model studies suggest an association between various psychiatric disorders and altered dendritic spine morphology. In the present study, we investigated the role of exogenous and endogenous PACAP in spine formation and maturation. PACAP modified the density and morphology of PSD-95-positive spines in primary cultured hippocampal neurons. Notably, PACAP increased the levels of microRNA (miR)-132 and decreased expression of corresponding miR-132 target genes and protein expression of p250GAP, a miR-132 effector known to be involved in spine morphology regulation. In corroboration, PSD-95-positive spines were reduced in PACAP-deficient (PACAP-/-) mice versus WT mice. Golgi staining of hippocampal CA1 neurons revealed a reduced spine densities and atypical morphologies in the male PACAP-/- mice. Furthermore, viral miR-132 overexpression reversed the reduction in hippocampal spinal density in the male PACAP-/- mice. These results indicate that PACAP signaling plays a critical role in spine morphogenesis possibly via miR-132. We suggest that dysfunction of PACAP signaling may contribute to the pathogenesis of neuropsychiatric disorders, at least partly through its effects on spine formation.SIGNIFICANCE STATEMENT Pituitary adenylate cyclase-activating polypeptide (PACAP) signaling dysfunction and dendritic spine morphology alterations have recently been suggested as important pathophysiological mechanisms underlying several psychiatric and neurological disorders. In this study, we investigated whether PACAP regulates dendritic spine morphogenesis. In a combination of pharmacological and viral gain- and loss-of-function approaches in vitro and in vivo experiments, we found PACAP to increase the size and density of dendritic spines via miR-132 upregulation. Together, our data suggest that a dysfunction of PACAP signaling may contribute to the pathogenesis of neuropsychiatric disorders, at least partly through abnormal spine formation.

MicroRNA-132 regulates total protein of Nav1.1 and Nav1.2 in the hippocampus and cortex of rat with chronic cerebral hypoperfusion

Nav1.1 and Nav1.2 are the voltage-gated sodium channel alpha subunit1 and 2, encoded by the genes of SCN1A and SCN2A. Previous studies have shown that chronic cerebral hypoperfusion (CCH) could induce neuropathological and cognitive impairment and increased total Nav1.1 and Nav1.2protein levels, yet the detailed mechanisms are not fully understood. MicroRNAs (miRNAs) are a class of small, non-coding RNAs that are involved in the regulation of dementia. miR-132 is known to play a key role in neurodegenerative disease. Here, we determined that miR-132 regulates Nav1.1 and Nav1.2 under CCH state. In this study, the expression of miR-132 was decreased in both the hippocampus and cortex of ratsfollowing CCH generated by bilateral common carotid artery occlusion (2VO). Lentiviral-mediated overexpression of miR-132 ameliorated dementia vulnerability induced by 2VO. At the molecular level, miR-132 repressed the increased protein expression of Nav1.1 and Nav1.2 in both the hippocampus and cortex induced by 2VO. MiR-132 suppressed, while AMO-miR-132 enhanced, the level of Nav1.1 and Nav1.2 in primary cultured neonatal rat neurons (NRNs) detected by both western blot analysis and immunofluorescence analysis. Results obtained by dual luciferase assay showed that overexpression of miR-132 inhibited the expression of Nav1.1 and Nav1.2 in human embryonic kidney 293 (HEK293T) cells. Additionally, binding-site mutation failed to influence Nav1.1 and Nav1.2, indicating that Nav1.1 and Nav1.2 are potential targets for miR-132. Taken together, our findings demonstrated that miR-132 protects against CCH-induced learning and memory impairments by down-regulating the expression of Nav1.1 and Nav1.2, and SCN1A and SCN2A are the target genes of miR-132.

A role for miR-132 in learned safety

Learned safety is a fear inhibitory mechanism, which regulates fear responses, promotes episodes of safety and generates positive affective states. Despite its potential as experimental model for several psychiatric illnesses, including post-traumatic stress disorder and depression, the molecular mechanisms of learned safety remain poorly understood, We here investigated the molecular mediators of learned safety, focusing on the characterization of miRNA expression in the basolateral amygdala (BLA). Comparing levels of 22 miRNAs in learned safety and learned fear trained mice, six safety-related miRNAs, including three members of the miR-132/-212 family, were identified. A gain-of-function approach based upon in-vivo transfection of a specific miRNA mimic, and miR-132/212 knock-out mice as loss-of-function tool were used in order to determine the relevance of miR-132 for learned safety at the behavioral and the neuronal functional levels. Using a designated bioinformatic approach, PTEN and GAT1 were identified as potential novel miR-132 target genes and further experimentally validated. We here firstly provide evidence for a regulation of amygdala miRNA expression in learned safety and propose miR-132 as signature molecule to be considered in future preclinical and translational approaches testing the transdiagnostic relevance of learned safety as intermediate phenotype in fear and stress-related disorders.

MiR-132/212 is induced by stress and its dysregulation triggers anxiety-related behavior

miR-132 and miR-212 are structurally-related microRNAs that are expressed from the same non-coding transcript. Accumulating evidence has shown that the dysregulation of these microRNAs contributes to aberrant neuronal plasticity and gene expression in the mammalian brain. Consistent with this, altered expression of miR-132 is associated with a number of affect-related psychiatric disorders. Here, we tested the functional contribution of the miR-132/212 locus to the development of stress-related and anxiety-like behaviors. Initially, we tested whether expression from the miR-132/212 locus is altered by stress-inducing paradigms. Using a 5-h acute-stress model, we show that both miR-132 and miR-212 are increased more than two-fold in the WT murine hippocampus and amygdala, whereas after a 15 day chronic-stress paradigm, expression of both miR-132 and miR-212 are upregulated more than two-fold within the amygdala but not in the hippocampus. Next, we used a tetracycline-inducible miR-132 overexpression mouse model and a miR-132/212 conditional knockout (cKO) mouse model to examine whether dysregulation of miR-132/212 expression alters basal anxiety-like behaviors. Interestingly, in both the miR-132 overexpression and cKO lines, significant increases in anxiety-like behaviors were detected. Importantly, suppression of transgenic miR-132 expression (via doxycycline administration) mitigated the anxiety-related behaviors. Further, expression of Sirt1 and Pten—two miR-132 target genes that have been implicated in the regulation of anxiety—were differentially regulated in the hippocampus and amygdala of miR-132/212 conditional knockout and miR-132 transgenic mice. Collectively, these data raise the prospect that miR-132 and miR-212 may play a key role in the modulation of stress responsivity and anxiety.

Retracted: Upregulated microRNA-132 rescues cardiac fibrosis and restores cardiocyte proliferation in dilated cardiomyopathy through the phosphatase and tensin homolog-mediated PI3K/Akt signal transduction pathway.

Cardiac fibrosis is known to be present in dilated cardiomyopathy (DCM) and it predicts the occurrence of sudden death and congestive heart failure. The aim of our study is to investigate the expression of microRNA-132 (miR-132) and its effect on cardiocyte proliferation, apoptosis, and cardiac fibrosis by binding to phosphatase and tensin homolog (PTEN) through the phosphateidylinositol 3-kinase (PI3K)/protein kinase (Akt) signal transduction pathway in DCM rats. DCM rat models induced by doxorubicin were established and confirmed by an ultrasonic cardiogram. Epithelial cells were treated with inhibitors, activators, and small interfering RNAs to identify the mechanisms by which miR-132 controls cardiocyte activity and cardiac fibrosis. Angiotensin II (Ang II) and aldosterone (ALD) expressions were detected by an enzyme-linked immunosorbent assay. The relationship between PTEN and miR-132 was verified by a dual-luciferase reporter assay. Cell proliferation and apoptosis were tested by the MTT assay and flow cytometry. PTEN was determined to be the target gene of miR-132. Rat models of DCM exhibited a lower level of miR-132, PI3K, Akt, B-cell lymphoma 2, collagen I, and collagen III, but a higher level of PTEN, Bcl-2-associated X protein, and proliferating cell nuclear antigen as well as inflammatory response (Ang II and ALD), accompanied by declined cardiocyte proliferation and elevated apoptosis and cardiac fibrosis. Upregulated miR-132 or silenced PTEN activated the PI3K/Akt pathway, thus facilitating cardiocyte proliferation and repressing cardiocyte apoptosis and cardiac fibrosis, as well as inflammatory responses. Downregulated miR-132 reversed this tendency. These findings indicate that miR-132 activates the PI3K/Akt pathway by inhibiting PTEN expression, thus facilitating cardiocyte proliferation and inhibiting apoptosis and cardiac fibrosis in DCM rats.

MicroRNA-132 attenuates LPS-induced inflammatory injury by targeting TRAF6 in neuronal cell line HT-22.

Epilepsy is a common neurological disorder in the central nervous system. Inflammation disrupts the blood-brain barrier (BBB), which is responsible for maintaining brain homeostasis. This study was aimed to investigate the functional role of microRNA (miR)-132 in hippocampal HT-22 cells under lipopolysaccharide (LPS) stimulation. In vitro cell inflammatory model was constructed by LPS stimulation. Inflammatory cell injury was evaluated according to the alterations of cell viability, apoptosis, and expression of inflammatory cytokines. Then, miR-132 level after LPS treatment was assessed. Subsequently, miR-132 was abnormally expressed after cell transfection, and the effects of miR-132 on LPS-induced cell inflammatory injury as well as phosphorylated levels of key kinases in the NF-κB and MAPK kinase (MEK)/ERK pathways were determined. The target gene of miR-132 was virtually screened and verified, and whether miR-132 affected HT-22 cells under LPS stimulation through regulating the target gene was verified. The results showed that the level of miR-132 was down-regulated by LPS in HT-22 cells, and the LPS-induced inflammatory injury could be reduced by miR-132 overexpression. Then, the phosphorylated levels of kinases in the NF-κB and MEK/ERK pathways were decreased by miR-132 overexpression. Tumor necrosis factor receptor-associated factor 6 (TRAF6) was predicted and verified to be a target of miR-132. Moreover, the alterations induced by miR-132 overexpression in the LPS-treated HT-22 cells were abrogated by TRAF6 overexpression. Therefore, we drew the conclusion that LPS down-regulated miR-132 and miR-132 attenuated LPS-induced inflammatory cell injury by targeting TRAF6, along with the inhibition of the NF-κB and MEK/ERK pathways.

MicroRNA-132 and microRNA-212 mediate doxorubicin resistance by down-regulating the PTEN-AKT/NF-κB signaling pathway in breast cancer

Breast cancer is a serious health problem worldwide. Acquisition of multi-drug resistance (MDR) during the treatment of breast cancer is still considered a major clinical obstacle. Despite the biological functions of miRNAs becoming increasingly apparent, the function of miRNAs in regulating drug resistance of breast cancer remains under investigation. Quantitative real-time PCR (qRT-PCR) was used to quantify the expression of miR-132/-212 (miR-132 and miR-212) in doxorubicin (DOX)-resistant and -sensitive breast cancer tumors and cells. The function of miR-132/-212 in drug resistance was investigated in vitro (MTT assay, TUNEL assay, fluorescence, immunohistochemistry, luciferase reporter assay, Western blotting). We found that miR-132/-212 were commonly overexpressed in DOX-resistant breast cancer tumors and cells. Silenced miR-132/-212 expression induced DOX accumulation in MCF-7/ADR cells, while overexpression of miR-132/-212 led to breast cancer resistance protein (BCRP)-based DOX efflux in MCF-7 cells. Further study showed that up-regulation of miR-132/-212 in MCF-7/ADR cells suppressed the expression of PTEN, a target gene of miR-132/-212, which activated AKT phosphorylation and the NF-κB pathway and led to increased BCRP expression. Down-regulation of miR-132/-212 sensitized MCF-7/ADR cells to DOX. Mechanistic investigations suggested that miR-132/-212 enhancement was a result of NF-κB-mediated transactivation of the pri-miR-132/-212 gene. Taken together, our findings are among the first to demonstrate a novel aspect of the miR-132/-212-PTEN-AKT/NF-κB-BCRP pathway in the generation of breast cancer resistance and provides a potential method to reverse drug resistance.

MicroRNA-132 protects hippocampal neurons against oxygen-glucose deprivation-induced apoptosis.

Hypoxic-ischemic brain injury (HIBI) results in death or long-term neurologic impairment in both adults and children. In this study, we investigated the effects of microRNA-132 (miR-132) dysregulation on oxygen-glucose deprivation (OGD)-induced apoptosis in fetal rat hippocampal neurons, in order to reveal the therapeutic potential of miR-132 on HIBI. MiR-132 dysregulation was induced prior to OGD exposure by transfection of primary fetal rat hippocampal neurons with miR-132 mimic or miR-132 inhibitor. The effects of miR-132 overexpression and suppression on OGD-stimulated hippocampal neurons were evaluated by detection of cell viability, apoptotic cells rate, and the expression of apoptosis-related proteins. Besides, TargetScan database and dual luciferase activity assay were used to seek a target gene of miR-132. As a result, miR-132 was highly expressed in hippocampal neurons following 2 h of OGD exposure. MiR-132 overexpression significantly increased OGD-diminished cell viability and reduced OGD-induced apoptosis at 12, 24, and 48 h post-OGD. MiR-132 overexpression significantly down-regulated the expressions of Bax, cytochrome c, and caspase-9, but up-regulated BCl-2. Caspase-3 activity was also significantly decreased by miR-132 overexpression. Furthermore, FOXO3 was a direct target of miR-132, and it was negatively regulated by miR-132. To conclude, our results provide evidence that miR-132 protects hippocampal neurons against OGD injury by inhibiting apoptosis.

HIV-1 Tat-shortened neurite outgrowth through regulation of microRNA-132 and its target gene expression.

BackgroundSynaptodendritic damage is a pathological hallmark of HIV-associated neurocognitive disorders, and HIV-1 Tat protein is known to cause such injury in the central nervous system. In this study, we aimed to determine the molecular mechanisms of Tat-induced neurite shortening, specifically the roles of miR-132, an important regulator of neurite morphogenesis in this process.MethodsThe relationship between Tat expression and miR-132 expression was first determined using reverse transcription quantitative PCR (qRT-PCR) in Tat-transfected astrocytes and neurons, astrocytes from Tat-transgenic mice, and HIV-infected astrocytes. qRT-PCR and Western blotting were performed to determine Tat effects on expression of miR-132 target genes methyl CpG-binding protein 2, Rho GTPase activator p250GAP, and brain-derived neurotrophic factor. Exosomes were isolated from Tat-expressing astrocytes, and exosomal microRNA (miRNA) uptake into neurons was studied using miRNA labeling and flow cytometry. The lactate dehydrogenase release was used to determine the cytotoxicity, while immunostaining was used to determine neurite lengths and synapse formation. Tat basic domain deletion mutant and miR-132 mimic and inhibitor were used to determine the specificity of the relationship between Tat and miR-132 and its effects on astrocytes and neurons and the underlying mechanisms of Tat-induced miR-132 expression.ResultsTat significantly induced miR-132 expression, ensuing down-regulation of miR-132 target genes in astrocytes and neurons. miR-132 induction was associated with phosphorylation of cAMP response element-binding protein and required the basic domain of Tat. miRNA-132 induction had no effects on astrocyte activation or survival but was involved in the direct neurotoxicity of Tat. miR-132 was present in astrocyte-derived exosomes and was taken up by neurons, causing neurite shortening.ConclusionsTat-induced miR-132 expression contributes to both direct and astrocyte-mediated Tat neurotoxicity and supports the important roles of miR-132 in controlling neurite outgrowth.

An Encapsulation of Gene Signatures for Hepatocellular Carcinoma, MicroRNA-132 Predicted Target Genes and the Corresponding Overlaps.

ObjectivesPrevious studies have demonstrated that microRNA-132 plays a vital part in and is actively associated with several cancers, with its tumor-suppressive role in hepatocellular carcinoma confirmed. The current study employed multiple bioinformatics techniques to establish gene signatures for hepatocellular carcinoma, microRNA-132 predicted target genes and the corresponding overlaps.MethodsVarious assays were performed to explore the role and cellular functions of miR-132 in HCC and a successive panel of tasks was completed, including NLP analysis, miR-132 target genes prediction, comprehensive analyses (gene ontology analysis, pathway analysis, network analysis and connectivity analysis), and analytical integration. Later, HCC-related and miR-132-related potential targets, pathways, networks and highlighted hub genes were revealed as well as those of the overlapped section.ResultsMiR-132 was effective in both impeding cell growth and boosting apoptosis in HCC cell lines. A total of fifty-nine genes were obtained from the analytical integration, which were considered to be both HCC- and miR-132-related. Moreover, four specific pathways were unveiled in the network analysis of the overlaps, i.e. adherens junction, VEGF signaling pathway, neurotrophin signaling pathway, and MAPK signaling pathway.ConclusionsThe tumor-suppressive role of miR-132 in HCC has been further confirmed by in vitro experiments. Gene signatures in the study identified the potential molecular mechanisms of HCC, miR-132 and their established associations, which might be effective for diagnosis, individualized treatments and prognosis of HCC patients. However, combined detections of miR-132 with other bio-indicators in clinical practice and further in vitro experiments are needed.

MiR-132 regulates osteogenic differentiation via downregulating Sirtuin1 in a peroxisome proliferator-activated receptor β/δ–dependent manner

MicroRNAs (miRNAs) play significant roles in multiple diseases by regulating the expression of their target genes. Type 2 diabetes mellitus (T2DM) is a chronic endocrine and metabolic disease with complex mechanisms. T2DM can result in diabetic osteoporosis (DO), which is characterized by bone loss, decreased bone mineral density and increased bone fractures. The promotion of osteogenic differentiation of osteoblasts is an effective way to treat osteoporosis. In the present study, high glucose (HG) and free fatty acids (FFA) were employed to mimic T2DM in MC3T3-E1 cells. To induce osteogenic differentiation, MC3T3-E1 cells were cultured in osteogenic medium. The results showed that osteogenic differentiation was significantly suppressed by HG and FFA. We found that miR-132 expression was significantly upregulated and much higher in HG-FFA–induced cells than other selected miRNAs, indicating that miR-132 might play an important role in DO. Furthermore, overexpression of miR-132 markedly inhibited the expression of key markers of osteogenic differentiation and alkaline phosphatase (ALP) activity. Reciprocally, inhibition of miR-132 restored osteogenic differentiation, even under treatment with HG-FFA. We also showed that Sirtuin 1 (Sirt1) was one of the target genes of miR-132, whose expression was controlled by miR-132. Ectopic expression of Sirt1 reversed the decrease in osteogenic differentiation caused by miR-132 and HG-FFA. These results demonstrated the direct role of miR-132 in suppressing osteogenic differentiation through downregulating Sirt1. Moreover, we demonstrated that peroxisome proliferator-activated receptor β/δ (PPARβ/δ) was a downstream molecule of Sirt1, and its knockout by PPARβ/δ siRNA significantly abolished the promotive effects of Sirt1 on osteogenic differentiation, indicating that Sirt1 functioned in a PPARβ/δ–dependent manner. Taken together, we provide crucial evidence that miR-132 plays a key role in regulating osteogenic differentiation through Sirt1 in a PPARβ/δ–dependent manner, indicating that miR-132 and Sirt1-PPARβ/δ may act as potential therapeutic targets for T2DM–induced osteoporosis.

Porphyromonas gingivalis-induced miR-132 regulates TNFα expression in THP-1 derived macrophages.

BackgroundPeriodontitis is a chronic inflammatory disease induced by periodontopathogens such as Porphyromonas gingivalis (P. gingivalis). MicroRNAs (miRNAs) are small single-stranded noncoding RNAs that regulate gene expression at the level of translation. MiRNAs have been reported to be involved in inflammatory processes. In this study, we examined the effects of P. gingivalis-induced inflammatory miRNAs expression on TNFα production in THP-1 derived macrophages.ResultsPorphyromonas gingivalis induced the expression of miR-132. P. gingivalis-induced miR-132 expression was significantly inhibited by TLR2/4 knock-down and NF-κB inhibitor. Additionally, miR-132 antagomir strongly repressed production of TNFα. The expression of NFE2L2 and NFAT5, the putative target genes of miR-132 involved in regulation of TNFα, decreased in response to P. gingivalis. Furthermore, miR-132 antagomir rescued P. gingivalis-induced suppression of NFE2L2 and NFAT5.ConclusionsThese results suggest that the induction of miR-132 by P. gingivalis can modulate the pathogenesis of periodontitis induced via regulatory expression of TNFα.

MiR-132 can inhibit glioma cells invasion and migration by target MMP16 in vitro.

Gliomas are the most common malignant primary brain tumors, and new clinical biomarkers and therapeutic targets are imminently required. MicroRNAs (miRNAs) are a novel class of small non-coding RNAs (∼22nt) involved in the regulation of various biological processes. Here, by using real-time polymerase chain reaction, miRNA-132 was found to be significantly deregulated in glioma tissues. Based on the prediction of the target genes of miR-132, we hypothesized that there is a significant association between miR-132 and matrix metalloproteinase (MMP) 16 (MT3-MMP), a protein of the MMP family. We showed that the up-expression of miR-132 inhibited cell migration and invasion in the human glioma cell lines A172, SHG44, and U87. Furthermore, the overexpression of miR-132 reduced the expression of MMP16 in A172, SHG44, and U87 cells. Taken together, our study suggested that miR-132 affects glioma cell migration and invasion by MMP16 and implicates miR-132 as a metastasis-inhibiting miRNA in gliomas.

MiR-132 inhibits lung cancer cell migration and invasion by targeting SOX4.

Multiple MicroRNAs (miRNAs) have been identified in the development and progression of lung cancer. However, the expression and roles of miR-132 in non-small cell lung cancer (NSCLC) remain largely undefined. The aim of this study is to investigate the biological functions and its molecular mechanisms of miR-132 in human lung cancer cells. miR-132 expression was measured in human lung cancer cell lines by quantitative real-time PCR (qRT-PCR). The cells migration and invasion ability were measured by wound healing assay and transwell assay. The influence of miR-132 on tumor progression in vivo was monitored using NSCLC xenografts in nude mice. The target gene of miR-132 was determined by luciferase assay and western blot. The expression level of miR-132 was dramatically decreased in examined lung cancer cell lines. Then, we found that introduction of miR-132 significantly suppressed the migration and invasion of lung cancer cells in vitro. Besides, miR-132 overexpression could also inhibit tumor growth in the nude mice. Further studies indicated that the sex determining region Y-box 4 (SOX4) is a target gene of miR-132. SOX4 re-introduction could reverse the anti-invasion role of miR-132. Our finding provides new insight into the mechanism of NSCLC progression. Therapeutically, miR-132 may serve as a potential target in the treatment of human lung cancer.

MicroRNA-132 inhibits cell growth and metastasis in osteosarcoma cell lines possibly by targeting Sox4.

Increasing evidence has confirmed that dysregulation of microRNAs (miRNAs) can contribute to the progression and metastasis of human tumors. Previous studies have shown that dysregulation of microRNAs (miRNAs) can contribute to the progression and metastasis of human tumors. However, the precise mechanisms of miR-132 in osteosarcoma have not been well clarified. Real-time PCR was performed to detect the expression of miR-132 in osteosarcoma cell lines. miR-132 mimic, miR-132 inhibitor and negative control were transfected into osteosarcoma cells and the effects of miR-132 on the cell growth and metastasis were investigated. Furthermore, protein level of Sox4 was measured by western blotting. Luciferase assays were performed to validate Sox4 as miR-132 target in osteosarcoma cells. We found that miR-132 was downregulated in osteosarcoma cell lines. Introduction of miR-132 significantly inhibited proliferation, arrested cell cycle and induced apoptosis in osteosarcoma cells. Besides, invasion and epithelial-mesenchymal transition (EMT) of osteosarcoma cells was suppressed by overexpressing miR-132. However, downregulation of miR-132 promoted cell growth and metastasis in osteosarcoma cells. Bioinformatics analysis predicted that Sox4 was a potential target gene of miR-132. Luciferase reporter assay demonstrated that miR-132 could directly target Sox4. Moreover, the low level of miR-132 was associated with increased expression of Sox4 in osteosarcoma cells. Sox4 inhibition suppressed cell malignant behaviors. Overexpression of Sox4 in osteosarcoma cells transfected with miR-132 mimic partially reversed the inhibitory effect of miR-132. In conclusion, miR-132 inhibited cell growth and metastasis in osteosarcoma cells by downregulation of Sox4, and knockdown of Sox4 was essential for the miR-132-inhibited cell growth and metastasis in osteosarcoma cells.

The SIRT1/TP53 axis is activated upon B-cell receptor triggering via miR-132 up-regulation in chronic lymphocytic leukemia cells.

The B-cell receptor (BCR) plays an important role in the pathogenesis and progression of chronic lymphocytic leukemia (CLL). By global microRNA profiling of CLL cells stimulated or not stimulated by anti-IgM, significant up-regulation of microRNAs from the miR-132~212 cluster was observed both in IGHV gene unmutated (UM) and mutated (M) CLL cells. Parallel gene expression profiling identified SIRT1, a deacetylase targeting several proteins including TP53, among the top-ranked miR-132 target genes down-regulated upon anti-IgM exposure. The direct regulation of SIRT1 expression by miR-132 was demonstrated using luciferase assays. The reduction of SIRT1 mRNA and protein (P = 0.001) upon anti-IgM stimulation was associated with an increase in TP53 acetylation (P = 0.007), and the parallel up-regulation of the TP53 target gene CDKN1A. Consistently, miR-132 transfections of CLL-like cells resulted in down-regulation of SIRT1 and an induction of a TP53-dependent apoptosis. Finally, in a series of 134 CLL samples, miR-132, when expressed above the median value, associated with prolonged time-to-first-treatment in patients with M CLL (HR = 0.41; P = 0.02). Collectively, the miR-132/SIRT1/TP53 axis was identified as a novel pathway triggered by BCR engagement that further increases the complexity of the interactions between tumor microenvironments and CLL cells.

Inhibition of miR-134 Protects Against Hydrogen Peroxide-Induced Apoptosis in Retinal Ganglion Cells.

MicroRNAs (miRNAs) have been suggested to play an important role in neurological diseases. Particularly, miR-134 is reportedly involved in regulating neuron survival. However, the association between miR-134 and retinal ganglion cell (RGC) survival under adverse stimulus has not been extensively investigated. In this study, we aimed to explore the role and underlying mechanism of miR-134 in regulating RGC apoptosis in response to hydrogen peroxide (H2O2) treatment. Results showed that the expression of miR-134 dose- and time-dependently increased in RGC after H2O2 treatment. H2O2-induced RGC apoptosis was significantly attenuated by the inhibition of miR-134 expression by antagomiR-134 and was enhanced by miR-134 overexpression. Luciferase reporter assay revealed a direct interaction between miR-134 and the 3'-untranslated region of cyclic AMP-response element-binding protein (CREB), a critical transcription factor for neuronal protection. In H2O2-treated RGCs, the inhibition of miR-134 significantly elevated the expression of CREB and its downstream genes, including brain-derived neurotrophic factor (BDNF) and Bcl-2. Furthermore, the inhibition of miR-134 also increased the expression of miR-132, a rapid response gene downstream of CREB. In addition, the target gene of miR-132, acetylcholinesterase was expectedly decreased by miR-134 inhibition. However, the overexpression of miR-134 exerted an opposite effect. The knockdown of CREB apparently abolished the protective effect of miR-134 inhibition against H2O2-induced RGC apoptosis. The increased expression of BDNF and Bcl-2 induced by miR-134 inhibition was also abrogated by CREB knockdown. Overall, our results suggested that the downregulation of miR-134 can effectively protect against H2O2-induced RGC apoptosis by negatively modulating CREB expression.

MiR-132 Suppresses the Migration and Invasion of Lung Cancer Cells via Targeting the EMT Regulator ZEB2

MicroRNAs (miRNAs) are small, non-coding RNAs which can function as oncogenes or tumor suppressor genes in human cancers. Emerging evidence reveals that deregulation of miRNAs contributes to the human non-small cell lung cancer (NSCLC). In the present study, we demonstrated that the expression levels of miR-132 were dramatically decreased in examined NSCLC cell lines and clinical NSCLC tissue samples. Then, we found that introduction of miR-132 significantly suppressed the migration and invasion of lung cancer cells in vitro, suggesting that miR-132 may be a novel tumor suppressor. Further studies indicated that the EMT-related transcription factor ZEB2 was one direct target genes of miR-132, evidenced by the direct binding of miR-132 with the 3′ untranslated region (3′ UTR) of ZEB2. Further, miR-132 could decrease the expression of ZEB2 at the levels of mRNA and protein. Notably, the EMT marker E-cadherin or vimentin, a downstream of ZEB2, was also down-regulated or up-regulated upon miR-132 treatment. Additionally, over-expressing or silencing ZEB2 was able to elevate or inhibit the migration and invasion of lung cancer cells, parallel to the effect of miR-132 on the lung cancer cells. Meanwhile, knockdown of ZEB2 reversed the enhanced migration and invasion mediated by anti-miR-132. These results indicate that miR-132 suppresses the migration and invasion of NSCLC cells through targeting ZEB2 involving the EMT process. Thus, our finding provides new insight into the mechanism of NSCLC progression. Therapeutically, miR-132 may serve as a potential target in the treatment of human lung cancer.