MicroRNA-133b Dysregulation in a Mouse Model of Cervical Contusion Injury.

Our previous research studies have demonstrated the role of microRNA133b (miR133b) in healing the contused spinal cord when administered either intranasally or intravenously 24 h following an injury. While our data showed beneficial effects of exogenous miR133b delivered within hours of a spinal cord injury (SCI), the kinetics of endogenous miR133b levels in the contused spinal cord and rostral/caudal segments of the injury were not fully investigated. In this study, we examined the miR133b dysregulation in a mouse model of moderate unilateral contusion injury at the fifth cervical (C5) level. Between 30 min and 7 days post-injury, mice were euthanized and tissues were collected from different areas of the spinal cord, ipsilateral and contralateral prefrontal motor cortices, and off-targets such as lung and spleen. The endogenous level of miR133b was determined by RT-qPCR. We found that after SCI, (a) most changes in miR133b level were restricted to the injured area with very limited alterations in the rostral and caudal parts relative to the injury site, (b) acute changes in the endogenous levels were predominantly specific to the lesion site with delayed miR133b changes in the motor cortex, and (c) ipsilateral and contralateral hemispheres responded differently to unilateral SCI. Our results suggest that the therapeutic window for exogenous miR133b therapy begins earlier than 24 h post-injury and potentially lasts longer than 7 days.

[Corrigendum] MicroRNA­133b targets TGFß receptor I to inhibit TGF­ß­induced epithelial­to­mesenchymal transition and metastasis by suppressing the TGF­ß/SMAD pathway in breast cancer.

Following the publication of the above article, an interested reader drew to the authors' attention that, for the MCF­7 cell migration assays shown in Fig. 3C on p. 1105, the representative images selected for the 'TGF­ß+ / miR­NC' and 'TGF­ß1­ / miR­NC' experiments were found to be overlapping, such that the data appeared to have been derived from the same original source. After having consulted their original data, the authors noted that the error had arisen during the process of assembling this figure, and the data chosen for the 'TGF­ß+ / miR­NC' panel had been selected incorrectly. The revised version of Fig. 3 is shown on the next page. The authors regret that these errors went unnoticed prior to the publication of this article, and thank the Editor of International Journal of Oncology for allowing them the opportunity to publish this corrigendum. All the authors agree with the publication of this corrigendum; furthermore, they also apologize to the readership of the journal for any inconvenience caused. [International Journal of Oncology 55: 1097­1109, 2019; DOI: 10.3892/ijo.2019.4879].

Intranasal Delivery of miR133b in a NEO100-Based Formulation Induces a Healing Response in Spinal Cord-Injured Mice.

Despite important advances in the pre-clinical animal studies investigating the neuroinhibitory microenvironment at the injury site, traumatic injury to the spinal cord remains a major problem with no concrete response. Here, we examined whether (1) intranasal (IN) administration of miR133b/Ago2 can reach the injury site and achieve a therapeutic effect and (2) NEO100-based formulation of miR133b/Ago2 can improve effectiveness. 24 h after a cervical contusion, C57BL6 female mice received IN delivery of miR133b/Ago2 or miR133b/Ago2/NEO100 for 3 days, one dose per day. The pharmacokinetics of miR133b in the spinal cord lesion was determined by RT-qPCR. The role of IN delivery of miR133b on motor function was assessed by the grip strength meter (GSM) and hanging tasks. The activity of miR133b at the lesion site was established by immunostaining of fibronectin 1 (FN1), a miR133b target. We found that IN delivery of miR133b/Ago2 (1) reaches the lesion scar and co-administration of miR133b with NEO100 facilitated the cellular uptake; (2) enhanced the motor function and addition of NEO100 potentiated this effect and (3) targeted FN1 expression at the lesion scar. Our results suggest a high efficacy of IN delivery of miR133b/Ago2 to the injured spinal cord that translates to improved healing with NEO100 further potentiating this effect.

Long non-coding RNA NCK1-AS1 functions as a ceRNA to regulate cell viability and invasion in esophageal squamous cell carcinoma via microRNA-133b/ENPEP axis.

This study is designed to explore the role of long non-coding RNAs (lncRNAs) NCK1-AS1 in proliferative and invasive activities of esophageal squamous cell carcinoma (ESCC) cells by binding to microRNA-133b (miR-133b) to regulate ENPEP. Differentially expressed lncRNAs, miRs, genes and their targeting relationships were screened on ESCC-related gene expression datasets GSE17351 and GSE6188. The targeting relationships among NCK1-AS1, miR-133b, and ENPEP were verified using functional assays. Loss- and gain- of function assays were carried out to examine the roles of NCK1-AS1, miR-133b, and ENPEP in ESCC cell proliferative, invasive, migrative and apoptotic abilities as well as tumorigenesis in vivo. Elevated NCK1-AS1 and ENPEP but reduced miR-133b expression were found in ESCC. NCK1-AS1 knockdown or miR-133b overexpression inhibited the malignant properties of ESCC cells as well as tumorigenesis in vivo. NCK1-AS1 regulated the ENPEP expression by competitively binding to miR-133b. ENPEP overexpression reversed inhibition of NCK1-AS1 knockdown on the function of ESCC cells. This study provides evidence that silencing NCK1-AS1 inhibits expression of ENPEP by sponging miR-133b, thereby suppressing ESCC.

Sevoflurane protects against intracerebral hemorrhage via microRNA-133b/FOXO4/BCL2 axis.

The application of Sevoflurane (Sev) in neurological diseases has been documented. We herein clarified the role of Sev in intracerebral hemorrhage (ICH). Through bioinformatics analysis, ICH-related microRNA (miRNA) was collected with microRNA-133b (miR-133b) chosen for the study subject. Then, the related downstream gene Forkhead box O4 (FOXO4) was identified. For in vivo assays, an ICH mouse model was established by autologous blood injection. For in vitro assays, hippocampal neurons were extracted from mouse brain tissues, and erythrocyte lysates were employed to simulate in vitro hemorrhage. Interaction between miR-133b and FOXO4 as well as between FOXO4 and BCL2 were assayed. We found decreased miR-133b in the brain tissue of ICH mice and erythrocyte lysate-treated hippocampal neurons. Sev treatment attenuated ICH and hippocampal neuronal apoptosis in mice by upregulating miR-133b. miR-133b targeted FOXO4 expression, and inhibition of FOXO4 attenuated hippocampal neuronal apoptosis by increasing BCL2 expression. Sev attenuated ICH in mice by increasing BCL2 expression through regulation of miR-133b-mediated FOXO4 expression. The findings highlighted the protective effect of Sev on ICH mice through the regulation of miR-133b-mediated FOXO4 expression.

MicroRNA-133b-3p Targets Purinergic P2X4 Receptor to Regulate Central Poststroke Pain in Rats.

Central poststroke pain (CPSP) is a neuropathic pain syndrome that usually occurs after cerebrovascular accidents. Currently, the pathogenesis of CPSP is not fully understood. Purinergic P2X4 receptor (P2X4R) is implicated in neuropathic pain including CPSP. Herein, we demonstrated that the levels of microRNA-133b-3p (miR-133b-3p), which targets P2X4R transcripts, were significantly downregulated in the ventral posterolateral nucleus of the thalamus (VPL), cerebrospinal fluid (CSF), and plasma of CPSP rats. The expression levels of miR-133b-3p negatively correlated with the severity of allodynia. Genetic knockdown of P2X4R in the VPL protected CPSP rats against allodynia. Similarly, genetic overexpression of miR-133b-3p in the VPL reversed the allodynia established in CPSP rats via downregulation of P2X4R expression. Treatment using gabapentin in CPSP rats significantly restored the decreased miR-133b-3p expression in the VPL, CSF, and plasma and blocked allodynia in CPSP rats. The administration of an miR-133b-3p inhibitor into the VPL abolished the antiallodynic activity of gabapentin. This mechanism was associated with P2X4R expression and involved the endogenous opioid system. Human patients with CPSP showed decreased plasma levels of miR-133b-3p compared with those of control participants. Logistic regression analysis of our patient cohort showed that determining plasma levels of miR-133b-3p may be useful for CPSP diagnosis and treatment.

Long non­coding RNA HCG18 facilitates the progression of laryngeal and hypopharyngeal squamous cell carcinoma by upregulating FGFR1 via miR­133b.

It has been reported that long non­coding RNA HLA complex group 18 (HCG18) is involved in the progression of cancer, acting as an oncogenic gene. The aim of the present study was to investigate the mechanism underlying the action of HCG18 in laryngeal and hypopharyngeal squamous cell carcinoma (LHSCC). The expression levels of HCG18, microRNA (miR)­133b and fibroblast growth factor receptor 1 (FGFR1) in LHSCC tissues and transfected LHSCC cells were evaluated by reverse transcription­quantitative PCR or immunohistochemistry. The viability, migration and invasion of transfected LHSCC cells were detected by Cell Counting Kit­8, wound healing and Transwell assays, respectively. The targeting relationships of HCG18, miR­133b and FGFR1 were predicted by bioinformatics analysis and confirmed using a dual­luciferase reporter assay. Moreover, the expression levels of FGFR1, phosphorylated (p)­PI3K, PI3K, p­AKT, AKT, p53, Bax and Bcl­2 in transfected LHSCC cells were measured by western blotting. It was found that the expression levels of HCG18 and FGFR1 were upregulated, but those of miR­133b were downregulated in LHSCC tissues. Short hairpin RNA (sh) HCG18 and miR­133b mimic inhibited LHSCC cell viability, while enhancing miR­133b expression. HCG18 could competitively bind with miR­133b. Moreover, the miR­133b inhibitor promoted cell viability, migration, invasion and the expression levels of Bcl­2, p­PI3K and p­AKT, but inhibited the expression levels of p53 and Bax, which were abrogated by shHCG18. miR­133b could competitively bind with FGFR1, and the miR­133b mimic decreased the expression level of FGFR1 in transfected LHSCC cells. shFGFR1 promoted the expression levels of p53 and Bax, while inhibiting viability, migration, invasion and Bcl­2, p­PI3K and p­AKT expression in LHSCC cells. In conclusion, the current results indicated that HCG18 facilitated the progression of LHSCC by upregulating FGFR1 via miR­133b. The present study evaluated the mechanism with regards to the action of HCG18 in LHSCC, and these experimental results may provide novel evidence for targeted therapy of LHSCC.

Effects of moxibustion on miRNA-133b, Pitx3/TH, and neurotransmitters in the midbrain of rats with diarrhea-predominant irritable bowel syndrome / 针灸推拿医学（英文版）

Objective: To investigate the mechanism of moxibustion in the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D), by observing the effects of moxibustion at Tianshu (ST25) and Shangjuxu (ST37) on microRNA-133b (miRNA-133b), pituitary homeobox family factor 3 (Pitx3)/tyrosine hydroxylase (TH), and neurotransmitters in the brain tissue of IBS-D rats. Methods: Healthy Sprague-Dawley rats were randomly divided into a normal group, a model group, a moxibustion group, and a Western medicine group, with 12 rats in each group. Except for the normal group, the IBS-D rat model was established by mother-offspring separation and acetic acid enema combined with restraint stress stimulation in all the other groups. No intervention was performed in the normal and model groups. Mild moxibustion was applied to both Tianshu (ST25) and Shangjuxu (ST37) in the moxibustion group. Rifaximin was given by gavage in the Western medicine group. The physical status of rats in each group was observed at different periods. After the intervention, hematoxylin- eosin staining was performed to observe the histopathological morphology of rat colon; enzyme-linked immunosorbent assay was used to measure the levels of dopamine (DA), noradrenaline (NE), and 5-hydroxytryptamine (5-HT) in plasma, colon, and midbrain tissue of rats; the relative expression levels of miRNA-133b, Pitx3 mRNA, and TH mRNA in the midbrain tissue were measured by real-time fluorescence quantitative polymerase chain reaction, and the relative expression levels of Pitx3 and TH proteins in the midbrain tissue were measured by Western blotting and immunofluorescence. Results: The body weights of rats among groups and at different time points were statistically different (P<0.01). The body weight of the normal group was higher than that of the other groups over time (P<0.01). After modeling, the minimum volume threshold of abdominal withdrawal reflex (AWR) was significantly lower (P<0.01) and the loose stool rate was significantly higher (P<0.01) in the model, moxibustion, and Western medicine groups compared with the normal group; the miRNA-133b expression in the midbrain tissue was significantly lower (P<0.01), the expression levels of Pitx3 and TH in the midbrain tissue were significantly higher (P<0.01), and the levels of DA, NE, and 5-HT in plasma, colon and midbrain tissue were significantly higher (P<0.01). After the intervention, the minimum volume threshold of AWR was significantly higher (P<0.01), the loose stool rate was significantly lower (P<0.01), the miRNA-133b expression was significantly increased (P<0.01 or P<0.05) and the expression levels of Pitx3 and TH were significantly decreased (P<0.01) in the midbrain tissue, the levels of DA, NE, and 5-HT in plasma, colon, and midbrain tissue were significantly reduced (P<0.01) in the moxibustion and Western medicine groups compared with the model group; the levels of 5-HT in the colon and midbrain tissue of the moxibustion group were significantly lower than those in the Western medicine group (P<0.05), and there was no statistical difference compared with the remaining groups (P>0.05). Linear correlation analysis showed that miRNA-133b was negatively correlated with Pitx3 (r<0, P<0.01); Pitx3 with TH, TH with DA, and NE with 5-HT were positively correlated (r>0, P<0.01).Conclusion: Moxibustion at Tianshu (ST25) and Shangjuxu (ST37) improves diarrhea symptoms and visceral hypersensitivity in IBS-D rats. The mechanism may be related to up-regulating miRNA-133b, inhibiting Pitx3/TH, and reducing neurotransmitter expression levels in the midbrain tissue.

[Effects of miR-133b on oxLDL-induced vascular endothelial cell injury by targeting SGTB].

Objective: To investigate the effect of microRNA-133b (miR-133b) on oxidized low density lipoprotein (oxLDL) induced vascular endothelial cell injury by targeting small protein molecules rich in glutamine 34-tetrapeptide repeats (SGTB). Methods: Human umbilical vein endothelial cells (EVC-304) were induced by 100 µg/ml oxLDL for 24 h to construct a vascular endothelial cell injury model. EVC-304 cells were divided into control group, oxLDL group (oxLDL treatment), oxLDL+miR-NC group (transfectted with 20 nmol/L miR-NC+oxLDL treatment), oxLDL+miR-133b group (transfectted with 20 nmol/L miR-133b mimics +oxLDL treatment), oxLDL+si-NC group (transfectted with 20 nmol/L si-NC+oxLDL treatment), oxLDL+si-SGTB group (transfected with 20 nmol/L si-SGTB+oxLDL treatment), oxLDL+miR-133b+ pcDNA group (transfected with 20 nmol/L si-SGTB and pcDNA+oxLDL), oxLDL+miR-133b+pcDNA-SGTB group (transfected with 20 nmol/L si-SGTB and pcDNA-SGTB), 9 wells in each group. Real-time quantitative PCR (qRT-PCR) and Western blot were used to detect the expression levels of miR-133b and SGTB; flow cytometry was used to detect cell apoptosis; kits were used to detect malondialdehyde (MDA) content and the activities of superoxide disproportionation enzyme (SOD) and glutathione peroxidase (GSH-Px). The expression levels of Bcl-2 and Bax protein were detected by Western blot. The dual luciferase reporter gene assay and Western blot were used to verify the targeted and regulatory between miR-133b and SGTB. Results: Compared with the control group, the expressions of miR-133b and Bcl-2 in EVC-304 cells were decreased significantly after oxLDL induction, while the expression levels of SGTB and Bax were sincreased ignificantly (P＜0.05), the MDA content and apoptosis rate were increased significantly (P＜0.05), and the activities of SOD and GSH-Px were decreased significantly (P＜0.05). Over-expression of miR-133b or interfering with SGTB inhibited oxLDL-induced apoptosis and oxidative stress in EVC-304 cells (P＜ 0.05). miR-133b directly bound to SGTB, miR-133b overexpression significantly down-regulated SGTB expression (P＜0.05), miR-133b inhibition significantly up-regulated SGTB expression (P＜0.05) Over-expression of SGTB reversed the effect of over-expressing miR-133b on oxLDL-induced vascular endothelial cell injury (P＜0.05). Conclusion: miR-133b could attenuate oxidative stress damage and apoptosis induced by oxLDL in vascular endothelial cells by targeting and inhibiting SGTB expression.

MicroRNA­133b alleviates doxorubicin­induced cardiomyocyte apoptosis and cardiac fibrosis by targeting PTBP1 and TAGLN2.

Doxorubicin is one of the most important chemotherapeutic drugs for the treatment of malignant tumors, but the cardiotoxicity of doxorubicin severely limits its clinical application. Increasing numbers of microRNAs (miRNAs/miRs) have been found to be dysregulated in doxorubicin­treated cardiomyocytes or animal hearts. The current study aimed to investigate the role of miR­133b in doxorubicin­induced cardiomyocyte injury. Doxorubicin was used to treat HL­1 cardiomyocytes to mimic cardiomyocyte injury in vitro. A mouse model of cardiac injury was generated by chronic intraperitoneal injections of doxorubicin. Masson's trichrome staining was performed on cardiac tissues to reveal cardiac fibrosis. Bioinformatics analysis and luciferase reporter assays were applied to explore the downstream targets of miR­133b. Flow cytometry and western blotting were conducted to detect cardiomyocyte apoptosis. Protein expression levels of collagen I, III and IV, and fibronectin were detected to reveal extracellular matrix deposition. The results revealed that doxorubicin decreased miR­133b expression in the treated HL­1 cardiomyocytes and mouse hearts. Overexpression of miR­133b restrained cardiomyocyte apoptosis, inhibited collagen accumulation and alleviated cardiac fibrosis in vivo. Mechanistically, polypyrimidine tract binding protein 1 (PTBP1) and transgelin 2 (TAGLN2) were confirmed to bind to miR­133b after prediction and screening. Moreover, miR­133b negatively regulated the protein expression levels of PTBP1 and TAGLN2. Finally, overexpression of PTBP1 or TAGLN2 reversed the effects of miR­133b on apoptosis and collagen accumulation. Thus, the current results indicated that miR­133b alleviated doxorubicin­induced cardiomyocyte apoptosis and cardiac fibrosis by targeting PTBP1 and TAGLN2, implying that miR­133b may be a potential biomarker for doxorubicin­induced cardiac injury.

Combined transplantation of neural stem cells and bone marrow mesenchymal stem cells promotes neuronal cell survival to alleviate brain damage after cardiac arrest via microRNA-133b incorporated in extracellular vesicles.

Neural stem cell (NSC) transplantation has prevailed as a promising protective strategy for cardiac arrest (CA)-induced brain damage. Surprisingly, the poor survival of neuronal cells in severe hypoxic condition restricts the utilization of this cell-based therapy. Extracellular vesicles (EVs) transfer microRNAs (miRNAs) between cells are validated as the mode for the release of several therapeutic molecules. The current study reports that the bone marrow mesenchymal stem cells (BMSCs) interact with NSCs via EVs thereby affecting the survival of neuronal cells. Hypoxic injury models of neuronal cells were established using cobalt chloride, followed by co-culture with BMSCs and NSCs alone or in combination. BMSCs combined with NSCs elicited as a superior protocol to stimulate neuronal cell survival. BMSCs-derived EVs could protect neuronal cells against hypoxic injury. Silencing of miR-133b incorporated in BMSCs-derived EVs could decrease the cell viability and the number of NeuN-positive cells and increase the apoptosis in the CA rat model. BMSCs-derived EVs could transfer miR-133b to neuronal cells to activate the AKT-GSK-3ß-WNT-3 signaling pathway by targeting JAK1. Our study demonstrates that NSCs promotes the release of miR-133b from BMSCs-derived EVs to promote neuronal cell survival, representing a potential therapeutic strategy for the treatment of CA-induced brain damage.

MicroRNA-133b expression inversely correlates with MET and can serve as an optimum predictive biomarker for patients of colorectal cancer.

BACKGROUND: Inactivation of the tumor suppressor gene microRNA-133b is a frequent event in various malignancies including colorectal cancer (CRC). The result of our previous research has found a statistically significant downregulation of microRNA-133b expression in human CRC cells, microRNA-133b can block the growth and metastatic progression of CRC cells in vitro and in vivo by targeting and repressing mesenchymal to epithelial transition factor. In this study, we identify the association between microRNA-133b, epithelial transition factor expression and clinicopathological parameters. METHODS: The detection of microRNA-133b and epithelial transition factor between gene and protein expression was evaluated in 46 patients with CRC. The correlation among microRNA-133b, epithelial transition factor and clinicopathological parameters associated with CRC was assessed. Furthermore, the diagnostic capability of microRNA-133b and epithelial transition factor in CRC was also evaluated. RESULTS: The results show decreased microRNA-133b expression in CRC tissues, and a very strong inverse correlation between the expression of oncogene epithelial transition factor and the expression of microRNA-133b. We also observed that the expression levels of microRNA-133b and epithelial transition factor were statistical associated with clinical stage and lymph node metastasis in CRC tissues, and further identified microRNA-133b and/or epithelial transition factor may be useful for distinguishing CRC patients from the normal population by receiver operating characteristic (ROC) curve analysis. CONCLUSIONS: microRNA-133b expression is inversely correlated with epithelial transition factor expression. MicroRNA-133b and/or epithelial transition factor may be useful as valuable prognostic biomarkers in CRC patients.

Long non-coding RNA EGFR-AS1 in colorectal cancer: potential role in tumorigenesis and survival via miRNA-133b sponge and EGFR/STAT3 axis regulation.

BACKGROUND: Colorectal cancer is one of the most common cancers worldwide and a major cause of cancer-related death. Thus molecular biomarkers for colorectal cancer have been proposed. The role of long non-coding RNA EGFR-AS1 in colorectal cancer is still unclear. We aimed to evaluate its expression in different stages of colorectal cancer and determine any possible role in regulating the miR­133b/EGFR/STAT3 signalling pathway. MATERIALS AND METHODS: The relative expression of EGFR-AS1 and miR­133b were evaluated by quantitative real-time RT-transcription PCR in 130 colorectal cancer samples and 30 normal tissues. EGFR expression was assessed using immunohistochemistry. Furthermore, levels of p-EGFR, p-STAT3, and apoptotic proteins were determined by ELISA. RESULTS: Both EGFR-AS1 and EGFR overexpression were positively linked with colorectal cancer status (both p < 0.01), grade (both p < 0.01), and metastasis (P < 0.01 and p = 0.019 respectively). EGFR-AS1 and miR-133b were significantly inversely correlated (P < 0.01). Low expression of miR-133b was inversely associated with overexpressed EGFR and increased p-STAT3 levels. EGFR-AS1 was an independent prognostic factor for survival of colorectal cancer patients (P < 0.01, HR 2.06; 95% CI 1.32-3.19) where low EGFR-AS1 expression was associated with higher survival rate (p = 0.003). CONCLUSION: EGFR-AS1 may have a role in colorectal cancer by regulation of miR­133b/EGFR/STAT3 signalling. It may be a potential biomarker for early diagnosis and predicting the survival rate of colorectal cancer.

Downregulation of circular RNA HECTD1 induces neuroprotection against ischemic stroke through the microRNA-133b/TRAF3 pathway.

AIMS: Circular RNAs (circRNAs) have been shown to play crucial roles in various biological processes and human diseases. However, their exact functions in ischemic stroke remain largely unknown. In this study, we explored the functional role of circRNA HECTD1 (circ-HECTD1) and its underlying mechanism in cerebral ischemia/reperfusion injury. METHODS: Mouse middle cerebral artery occlusion (MCAO) model and oxygen-glucose deprivation (OGD) model in HT22 cells were used to mimic the cerebral ischemia/reperfusion injury. Brain infarct volume, flow cytometry, caspase 3 activity, NF-κB activity, and TUNEL staining were performed to evaluate the function of circ-HECTD1. Luciferase report assay was used to explore the regulatory mechanism. FINDINGS: The results showed that the expression of circ-HECTD1 and tumor necrosis factor receptor-associated factor 3 (TRAF3) was remarkably up-regulated, while miR-133b was down-regulated in oxygen-glucose deprivation (OGD)-induced HT22 cells and mouse middle cerebral artery occlusion (MCAO) model. circ-HECTD1 knockdown relieved OGD-caused neuronal cell death in vitro. Simultaneously, circ-HECTD1 knockdown improved cerebral infarction volume and neuronal apoptosis in MCAO mice. circ-HECTD1 was able to negatively regulate the expression of miR-133b, and TRAF3 is one of the targets of miR-133b. Upregulation of miR-133b inhibited the expression of TRAF3 in OGD-stimulated cells, whereas circ-HECTD1 upregulation reversed this effect. Furthermore, upregulation of miR-133 was able to inhibit OGD-caused cell apoptosis and NF-κB activation, whereas upregulation of circ-HECTD1 attenuated these effects of miR-133b mimics. SIGNIFICANCE: Taken together, circ-HECTD1 knockdown inhibited the expression of TRAF3 by targeting miR-133b, thereby attenuating neuronal injury caused by cerebral ischemia.

Exosome-transmitted microRNA-133b inhibited bladder cancer proliferation by upregulating dual-specificity protein phosphatase 1.

Bladder Cancer (BC) is the ninth most common tumor in the world and one of the most common malignant tumors of the urinary system. Some studies reported that miR-133b expression is reduced in BC, but whether it plays a role in the development of BC and its mechanism is unclear. microRNAs can be packaged into exosomes to mediate communication between tumor cells, affecting their proliferation and apoptosis. The objective of this study was to investigate the effect of exosomal miR-133b on BC proliferation and its molecular mechanism. Firstly, the expression of miR-133b was evaluated in BC and adjacent normal tissues, as well as in serum exosomes of BC patients and healthy controls. Then the delivery and internalization of exosomes in cells was observed through fluorescence localization. Cell viability and apoptosis were assessed in BC cells transfected with mimics and incubated with exosomes. The role of exosomal miR-133b was also analyzed in nude mice transplant tumors. Furthermore, the target gene of miR-133b was predicted through bioinformatics. The level of miR-133b was significantly decreased in BC tissues and in exosomes from serum of patients, which was correlated with poor overall survival in TCGA. Exosomal miR-133b could be obtained using BC cells after transfection with miR-133b mimics. The miR-133b expression increased after incubation with exosomal miR-133b, which lead to the inhibition of viability and increase of apoptosis in BC cells. Exosomal miR-133b could suppress tumor growth in vivo. In addition, we found that exosomal miR-133b may play a role in suppressing BC proliferation by upregulating dual-specificity protein phosphatase 1 (DUSP1). These findings may offer promise for new therapeutic directions of BC.

Human umbilical cord mesenchymal stem cell-derived exosome-mediated transfer of microRNA-133b boosts trophoblast cell proliferation, migration and invasion in preeclampsia by restricting SGK1.

OBJECTIVE: Exosomes have been documented to function in human diseases, yet their transfer of microRNA (miRNA) in preeclampsia (PE) has seldom been reported. This study intends to discuss the role of miR-133b derived from exosomes in human umbilical cord mesenchymal stem cells (hUC-MSCs) in trophoblast cell development in PE. METHODS: Placentas from PE patients and normal pregnant women were collected. The hUC-MSCs and their exosomes were obtained and identified. Trophoblast cell HPT-8 and HTR8-S/Vneo were obtained and co-cultured with hUC-MSCs-derived exosomes that had been transfected with different miR-133b plasmids. MiR-133b and glucocorticoid-regulated kinase 1 (SGK1) expression in placental tissues and HPT-8 and HTR8-S/Vneo cells was determined. HTR8-S/Vneo and HPT-8 cell proliferation, cell cycle distribution, apoptosis rate, migration and invasion were detected. RESULTS: MiR-133b was down-regulated and SGK1 was up-regulated in placental tissues of PE patients. MiR-133b expression was inversely related to SGK1 expression in HTR8-S/Vneo and HPT-8 cells co-cultured with hUC-MSC-derived exosomes. Exosomes promoted HTR8-S/Vneo and HPT-8 cell proliferation, migration and invasion abilities, cell cycle entry and inhibited apoptosis. Elevated exosome-derived miR-133b from hUC-MSCs boosted HTR8-S/Vneo and HPT-8 cell proliferation, cell cycle progression, migration and invasion and limited cell apoptosis. MiR-133b targeted SGK1. CONCLUSION: Collectively, we demonstrate that miR-133b is down-regulated and SGK1 is up-regulated in PE, and miR-133b derived from exosomes in hUM-MSCs facilitates trophoblast cell proliferation, migration and invasion in PE via constraining SGK1.

miR­133b affects cell proliferation, invasion and chemosensitivity in renal cell carcinoma by inhibiting the ERK signaling pathway.

Renal cell carcinoma has the highest incidence rate of cancer types in the urinary system. Moreover, microRNAs (miRNA) have been closely associated with numerous types of tumor. The present study aimed to investigate the effects of miRNA (miR)­133b on the proliferation, invasion and chemosensitivity of renal cell carcinoma cells, and to determine whether its mechanism was regulated by the ERK signaling pathway. Both renal cell carcinoma and adjacent healthy tissues from 60 patients, in addition to renal cell carcinoma lines, ACHN, Caki­1, A­498 and 786­O, and 293 cells, were used in this study. miR­133b expression was measured from renal cell carcinoma, adjacent healthy tissues and renal cell carcinoma cell lines by reverse transcription­quantitative PCR. Cells were transfected with miR­133b mimic to achieve miR­133b overexpression. The proliferative, migratory and invasive ability of the cells were evaluated using MTT, wound healing and Matrigel assays, respectively, and flow cytometry was used to detect the apoptotic rate. Following treatment with an ERK inhibitor, U0126, and activator, LM22B­10, western blotting was used to detect the expression of related proteins and the activity of the ERK signaling pathway. The overexpression of miR­133b significantly inhibited cell proliferation, migration and invasion, whilst inducing apoptosis and increasing the drug sensitivity of renal cell carcinoma cells to cisplatin, docetaxel and doxorubicin. The miR­133b mimic also increased the protein expression levels of Bax and decreased the expression levels of matrix metalloproteinase (MMP)­2, MMP­9, ATP­binding cassette subfamily G2, P­glycoprotein, Bcl­2 and proliferating cell nuclear antigen, as well as the phosphorylation of ERK (P<0.05). The administration of the U0216 inhibitor demonstrated similar effects to miR­133b overexpression, and there was no significant difference compared with the miR­133b mimic transfection (P>0.05). However, the overexpression of miR­133b combined with LM22B­10 treatment weakened the anticancer effects of miR­133b mimic transfection (P<0.05). In conclusion, miR­133b overexpression was observed to inhibit the proliferation, migration and invasion of renal cell carcinoma cells and improve chemotherapeutic sensitivity; it was suggested that the mechanism maybe related to the inhibition of ERK1/2 phosphorylation and thus decreased ERK signaling pathway activity.

Intravenous delivery of microRNA-133b along with Argonaute-2 enhances spinal cord recovery following cervical contusion in mice.

BACKGROUND CONTEXT: Acute spinal cord injury (SCI) is a devastating condition for which spine decompression and stabilization of injury remains the only therapy available in the clinical setup. However, fibrous scar formation during the healing process significantly impairs full recovery. MicroRNAs (miRs) are small noncoding RNAs that regulate gene expression by binding to target mRNA(s) and initiating translational repression or mRNA degradation. It has been reported that microRNA-133b (miR133b) is highly expressed in regenerating neurons following a SCI in zebrafish, and lentiviral delivery of miR133b at the time of SCI in mice resulted in improved functional recovery. PURPOSE: The aim of this study was to investigate whether intravenous delivery of miR133b enhances spinal cord recovery when administered 24 hours following a cervical contusion injury in mice. STUDY DESIGN: This is an experimental animal study of acute SCI, investigating the effect of miR133b on spinal cord recovery by targeting scar lesion formation. The approach involved setting an acute SCI in mice, which was followed 24 hours later by intravenous co-delivery of miR133b and Argonaute 2 (Ago2), a protein involved in miRNA stabilization. Readouts of the impact of this intervention included analysis of RNA and protein expression at the lesion site, in particular with regard to markers of scar tissue formation, and determination of motor function recovery by the grip strength meter task. METHODS: C57BL6 female mice between 6 and 8 weeks of age were tested. The injury model employed was a unilateral moderate contusion at the cervical fifth level. Twenty-four hours following the injury, the authors co-delivered miR133b, or scrambled miRNA as negative control, along with Ago2 for 3 consecutive days, one dose per day via tail-vein injection. They first investigated the level of miR133b in the spinal cord and in spinal cord lesion after a single dose of injection. Next, they determined the efficacy of miR133b and/or Ago2 delivery in regulating gene and protein expression at the lesion site. Finally, they established the role of miR133b and/or Ago2 in enhancing forelimb gripping recovery as assessed by the grip strength meter task for 8 weeks post-SCI. RESULTS: Intravenous delivery of miR133b and/or Ago2 targeted the microenvironment at the lesion site and prevented the increased expression of certain extracellular matrix proteins (ECM), in particular collagen type 1 alpha 1 and tenascin N, which are known to have a key role in scar formation. It also reduced microglia and/or macrophage recruitment to the lesion site. Functional recovery in mice treated with miR133b and/or Ago2 started around 2 weeks postinjury and continued to improve over time, whereas mice in the control group displayed significantly poorer recovery. CONCLUSIONS: Our data indicate therapeutic activity of intravenous miR133b and/or Ago2 treatment, possibly via decreasing ECM protein expression and macrophage recruitment at the lesion site, thereby minimizing detrimental fibrous scar formation. CLINICAL SIGNIFICANCE: There is an urgent medical need for better treatments of SCIs. Based on our findings in a preclinical model, the miR133b and/or Ago2 system specifically targets fibrous scar formation, a barrier in neuronal regrowth, by remodeling ECM molecules at the injury site. Prevention of scar formation is critical to improved outcomes of treatment. Of note, delivery of miR133b and/or Ago2 was initiated 24 hours after traumatic impact, thus indicating a fairly long window of opportunity providing more time and flexibility for therapeutic intervention. Intravenous miR133b may become a beneficial therapeutic strategy to treat patients with acute SCI.

The protective role of microRNA-133b in restricting hippocampal neurons apoptosis and inflammatory injury in rats with depression by suppressing CTGF.

OBJECTIVE: Increasing evidence has proved the functions of microRNAs (miRNAs) in human diseases, our research was designed to explore the effects of miR-133b on the progression of depression with the involvement of connective tissue growth factor (CTGF). METHODS: Depression rat models were established by chronic unpredictable mild stress, then the ethology of rats in each group was observed, and the morphological changes as well as the apoptosis of hippocampal neurons was measured. Subsequently, the expression of miR-133b, CTGF, glial fibrillary acidic protein (GFAP), brain-derived neurotrophic factor (BDNF), Bax, Bcl-2, interleukin-1ß (IL-1ß), IL-6, tumor necrosis factor-α (TNF-α) and neurotransmitters was determined. The target relation between miR-133b and CTGF was assessed. RESULTS: We have found in this study that miR-133b was poorly expressed, and CTGF was highly expressed in hippocampal tissues of depression rats. Additionally, elevated miR-133b and inhibited CTGF could restrain apoptosis of hippocampal neurons, repress inflammatory reaction, and increase the expression of GFAP, BDNF and neurotransmitters in hippocampal tissues of depression rats, resulting in a protective impact on neural injury in depression rats. CONCLUSION: This study demonstrates that elevated miR-133b could suppress the expression of CTGF to protect the hippocampal neurons from apoptosis and inflammatory injury in depression rats.

Mesenchymal stem cell-derived exosomal microRNA-133b suppresses glioma progression via Wnt/ß-catenin signaling pathway by targeting EZH2.

BACKGROUND: Mesenchymal stem cells (MSCs) play a significant role in cancer initiation and metastasis, sometimes by releasing exosomes that mediate cell communication by delivering microRNAs (miRNAs). This study aimed to investigate the effects of exosomal miR-133b derived from MSCs on glioma cell behaviors. METHODS: Microarray-based analysis identified the differentially expressed genes (DEGs) in glioma. The expression patterns of EZH2 and miR-133b along with interaction between them were clarified in glioma. The expression of miR-133b and EZH2 in glioma cells was altered to examine their functions on cell activities. Furthermore, glioma cells were co-cultured with MSC-derived exosomes treated with miR-133b mimic or inhibitor, and EZH2-over-expressing vectors or shRNA against EZH2 to characterize their effect on proliferation, invasion, and migration of glioma cells in vitro. In vivo assays were also performed to validate the in vitro findings. RESULTS: miR-133b was downregulated while EZH2 was upregulated in glioma tissues and cells. miR-133b was found to target and negatively regulate EZH2 expression. Moreover, EZH2 silencing resulted in inhibited glioma cell proliferation, invasion, and migration. Additionally, MSC-derived exosomes containing miR-133b repressed glioma cell proliferation, invasion, and migration by inhibiting EZH2 and the Wnt/ß-catenin signaling pathway. Furthermore, in vivo experiments confirmed the tumor-suppressive effects of MSC-derived exosomal miR-133b on glioma development. CONCLUSION: Collectively, the obtained results suggested that MSC-derived exosomes carrying miR-133b could attenuate glioma development via disrupting the Wnt/ß-catenin signaling pathway by inhibiting EZH2, which provides a potential treatment biomarker for glioma.