The microRNA-211-5p/P2RX7/ERK/GPX4 axis regulates epilepsy-associated neuronal ferroptosis and oxidative stress.

Ferroptosis is an iron-dependent cell death mechanism involving the accumulation of lipid peroxides. As a critical regulator, glutathione peroxidase 4 (GPX4) has been demonstrated to be downregulated in epilepsy. However, the mechanism of ferroptosis in epilepsy remains unclear. In this study, bioinformatics analysis, analysis of epilepsy patient blood samples and cell and mouse experiments revealed strong associations among epilepsy, ferroptosis, microRNA-211-5p and purinergic receptor P2X 7 (P2RX7). P2RX7 is a nonselective ligand-gated homotrimeric cation channel, and its activation mainly increases neuronal activity during epileptic seizures. In our study, the upregulation of P2RX7 in epilepsy was attributed to the downregulation of microRNA (miR)-211-5p. Furthermore, P2RX7 has been found to regulate GPX4/HO-1 by alleviating lipid peroxidation induced by suppression of the MAPK/ERK signaling pathway in murine models. The dynamic decrease in miR-211-5p expression induces hypersynchronization and both nonconvulsive and convulsive seizures, and forebrain miR-211-5p suppression exacerbates long-lasting pentylenetetrazole-induced seizures. Additionally, in this study, induction of miR-211-5p expression or genetic-silencing of P2RX7 significantly reduced the seizure score and duration in murine models through the abovementioned pathways. These results suggest that the miR-211-5p/P2RX7 axis is a novel target for suppressing both ferroptosis and epilepsy.

miRNA-211-5p inhibition enhances the protective effect of hucMSC-derived exosome in Aß1-40 -induced SH-SY5Y cells by increasing NEP expression.

Exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs) could alleviate Alzheimer's disease (AD) defects. Additionally, engineered exosomes are more effective in treating diseases. In this study, we established an in vitro model of AD by treating SH-SY5Y cells with Aß1-40 . We observed that incubation with hucMSC-derived exosomes effectively protected SH-S5Y5 cells from Aß1-40 -induced damage. Since NEP plays a central role in suppressing AD development, we screened NEP-targeting miRNAs that are differentially expressed in control and AD patients. We identified miR-211-5p as a potent repressor of NEP expression. Exosomes purified from hucMSCs overexpressing miR-211-5p inhibitor exhibited significantly greater efficiency than control exosomes in mitigating the injury caused by Aß1-40 treatment. However, this enhanced protective effect was nullified by the knockdown of NEP. These observations demonstrate that inhibition of miR-211-5p has the potential to improve the efficacy of hucMSC-derived exosomes in AD treatment by increasing NEP expression.

Functional effects of microRNA-211-5p-targeted inhibition of erythropoietin hepatocyte kinase receptor and ligand B2 signaling pathway on spinal cord nerve injury / 中国医师进修杂志

Objective:To detect the expression of microRNA (miR)-211-5p, erythropoietin hepatocyte kinase receptor B2 (EphB2) and erythropoietin hepatocyte kinase ligand B2 (ephrin B2) in spinal cord tissues as well as nerve cells after spinal cord injury (SCI), and to explore their mechanisms and effects on neurological recovery in SCI rats.Methods:The study was conducted from May 2020 to June 2021 using Sprague Dawley (SD) rats and PC12 cells. SD rats were divided into sham-operated group and SCI group of 30 rats each, and Basso-Beattie-Bresnahan (BBB) score were performed at different postoperative time points (1, 3, 7, 14, 21 and 28 d), and the relative expression of miR-211-5p and Eph/ephrin B2 mRNA was measured by quantitative real-time polymerase chain reaction (qPCR); the SCI rats were divided into recombinant lentiviral vector LV-miR-211-5p group (group A), empty lentiviral vector LV-eGFP (group B) and saline group (group C), with 15 rats in each group, respectively. The recombinant lentiviral vector, empty lentiviral vector and saline were injected on the cephalic and caudal sides of the spinal cord injury, and the relative expression of miR-211-5p and Eph/ephrin B2 mRNA in the spinal cord tissue was measured at 1, 7 and 14 d after surgery. In addition, a PC12 injury cell line model was established with 150 μmol/L hydrogen peroxide (H 2O 2), and the apoptosis rate and apoptosis-related proteins and contents of different cell lines were detected by flow cytometry and Western blot, respectively. MiR-211-5p was verified to target EphB2 by dual luciferase reporter gene. Results:The results of the animal experiments showed that at different postoperative time points, the miR-211-5p levels in the SCI group were lower than those in the SHAM group: 0.70 ± 0.03 vs. 1.00 ± 0.10, 0.60 ± 0.04 vs. 1.00 ± 0.05, 0.45 ± 0.10 vs. 1.00 ± 0.12, 0.30 ± 0.06 vs. 1.00 ± 0.15, 0.20 ± 0.05 vs. 1.00 ± 0.13, 0.10 ± 0.02 vs. 1.00 ± 0.07. In contrast, levels of Eph/ephrin B2 were higher in the SCI group compared to the SHAM group: 1.10 ± 0.05 vs. 1.00 ± 0.01, 1.80 ± 0.01 vs. 1.00 ± 0.08, 2.30 ± 0.01 vs. 1.00 ± 0.10, 2.60 ± 0.01 vs. 1.00 ± 0.05, 2.80 ± 0.01 vs. 1.00 ± 0.06, 3.00 ± 0.01 vs. 1.00 ± 0.07 and 1.20 ± 0.05 vs. 1.00 ± 0.02, 1.60 ± 0.01 vs. 1.00 ± 0.03, 2.10 ± 0.10 vs. 1.00 ± 0.01, 2.40 ± 0.11 vs. 1.00 ± 0.09, 2.70 ± 0.13 vs. 1.00 ± 0.05, 2.90 ± 0.12 vs. 1.00 ± 0.03 ( P<0.05). At 14 d after surgery, Group A exhibited higher BBB scores than Groups B and C: (14.0 ± 1.1) points vs. (8.0 ± 1.1) and (8.2 ± 1.2) points, while miR-211-5p levels were higher than those in Groups B and C: 1.90 ± 0.10 vs. 0.40 ± 0.01 and 0.50 ± 0.02, and Eph/ephrin B2 levels were lower than those in Groups B and C: 0.70 ± 0.10 vs. 1.80 ± 0.04 and 1.90 ± 0.06, 0.60 ± 0.03 vs. 2.00 ± 0.04 and 2.10 ± 0.05 ( P<0.05). Immunofluorescence staining showed that the levels of GAP-43 and synaptophysin in group A were higher than those in groups B and C at 14 d after surgery ( P<0.05). Cellular assays showed that overexpression of miR-211-5p inhibited the apoptosis rate of H 2O 2-induced PC12 cells and the expression of the apoptosis-related gene Cleaved-caspase3 ( P<0.05). Knockdown of miR-211-5p increased the apoptosis rate of H 2O 2-induced PC12 cells and the expression of the apoptosis-related gene Cleaved-caspase3 ( P<0.05). Dual luciferase reporter gene assay confirmed that EphB2 was a target gene of miR-211-5p and overexpression of EphB2 antagonized the inhibitory apoptosis effect of miR-211-5p on H 2O 2-induced PC12 cells. Conclusions:This study showed that miR-211-5p could promote neurological repair in SCI by inhibiting the expression of Eph/ephrin B2 signaling pathway, suggesting that using miR-211-5p as a target to inhibit Eph/ephrin B2 signaling pathway may have a protective effect on SCI.

Eupatilin ameliorates postmenopausal osteoporosis via elevating microRNA-211-5p and repressing JAK2/STAT3 pathway.

Postmenopausal osteoporosis (PMOP) poses a significant threat to women's health worldwide. Eupatilin is a key bioactive component of the Chinese herbal medicine Artemisia asiatica Nakai. Recent research reports have proved the inhibitory function of Eupatilin in many diseases. MicroRNAs (miRNAs) are 21-23 nucleotide-long, single-stranded, noncoding RNA molecules generated endogenously, and many studies have indicated that miRNAs are involved in the development of osteoporosis. This study explored the role and potential mechanism of Eupatilin underlying PMOP. First, rats were given intragastric administration of Eupatilin every day and subcutaneous injections of oligonucleotides or plasmids that interfered with miR-211-5p or janus kinase 2 (JAK2) once a week. After 4 weeks, the PMOP rat model was established. Then, serum alkaline phosphatase, calcium, and phosphorus levels, as well as femur bone mineral density and biomechanical parameters, were detected. Hematoxylin-eosin staining and Masson staining were applied for detecting the pathological condition of femur, and immunohistochemical staining was for detecting osteocalcin. MC3T3-E1 cells were transfected with plasmid vectors interfering with miR-211-5p or JAK2; and cell viability, lactate dehydrogenase cytotoxicity, and cell mineralization were subsequently examined. The relationship between miR-211-5p and JAK2/signal transducer and activator of transcription 3 (STAT3) pathway was analyzed. The targeting relation between miR-211-5p and JAK2 was also verified. The experimental results revealed that Eupatilin improved the pathological conditions of PMOP rats by promoting the proliferation and mineralization of osteoblasts. MiR-211-5p was down-regulated and JAK2/STAT3 was upregulated in PMOP rats. Upregulation of miR-211-5p further improved the pathological conditions of PMOP rats based on Eupatilin treatment. MiR-211-5p inhibited the JAK2/STAT3 pathway. JAK2 offset the effects of elevated miR-211-5p on PMOP rats. Overall, Eupatilin attenuates PMOP through elevating miR-211-5p and repressing JAK2/STAT3 pathway, which suggests the utility of Eupatilin as a potential drug for POMP treatment.

Eupatilin ameliorates postmenopausal osteoporosis via elevating microRNA-211-5p and repressing Janus kinase 2/Signal transducer and activator of transcription 3 pathway.

This study explored the effect of Eupatilin on postmenopausal osteoporosis and explored the mechanisms associated with miR-211-5p. First, the rats were given intragastric administration of Eupatilin every day and subcutaneously injected once a week with oligonucleotides or plasmids that interfered with the expression of miR-211-5p or Janus kinase 2 (JAK2). After 4 weeks, a rat model of osteoporosis was established. Then, serum alkaline phosphatase, calcium and phosphorus levels were detected, as well as femur bone mineral density and biomechanical parameters. HE staining and Masson staining were applied for detecting the pathological condition of femur while immunohistochemical staining was for detecting the positive expression of osteocalcin. In addition, MC3T3-E1 cells were transfected with plasmid vectors interfering with miR-211-5p or JAK2, and cell viability, lactate dehydrogenase cytotoxicity, and cell mineralization were subsequently examined. The relationship between miR-211-5p and JAK2/Signal transducer and activator of transcription 3 (STAT3) pathway was analyzed, and the targeting of miR-211-5p and JAK2 was also verified. The experimental results found that Eupatilin improved the pathological conditions of osteoporotic rats by promoting the proliferation and mineralization of osteoblasts. miR-211-5p was down-regulated and JAK2/STAT3 were up-regulated in osteoporotic rats. Upregulation of miR-211-5p further improved the pathological conditions of osteoporotic rats based on Eupatilin treatment. MiR-211-5p inhibited the JAK2/STAT3 pathway. Upregulation of JAK2 reversed the effects of elevated miR-211-5p on osteoporotic rats. Overall, Eupatilin attenuates postmenopausal osteoporosis through elevating miR-211-5p and repressing JAK2/STAT3 pathway.

MicroRNA-211 Regulates Proliferation, Expansion, and Immune Inhibitory Function of Myeloid-Derived Suppressor Cells via Mediation of CHOP Expression.

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) are capable of effectively repressing immune responses against tumors and orchestrating the tumor microenvironment, which can promote tumor angiogenesis and metastasis. The pathway networks used to modulate tumor-expanded MDSC accumulation and function remain unclear. This study identified microRNA-211 (miR-211), whose expression was significantly decreased by factors derived from tumors. METHODS: miR-211 was assumed to be critical in modulating the accumulation and activity of MDSCs isolated from ovarian cancer (OC)-bearing mice by targeting C/EBP homologous protein (CHOP). RESULTS: The upregulation of miR-211 repressed MDSC proliferation, inhibited MDSC immunosuppressive functions, and increased the number of co-incubated CD4+ and CD8+ cells. Furthermore, overexpression of miR-211 led to decreased activities of the NF-κB, PI3K/Akt, and STAT3 pathways and the subsequent downregulation of matrix metalloproteinases to promote tumor cell invasion and metastasis. CHOP overexpression counteracted the effects of miR-211 elevation on these phenotypic changes. Upregulation of miR-211 also dramatically impaired the activity of MDSCs and suppressed OC tumor growth in vivo. CONCLUSION: These results indicated that the miR-211-CHOP axis in MDSCs plays an essential role in the metastasis and proliferation of tumor-expanded MDSCs and might represent a promising cancer treatment target.

Three-dimensional ordered DNA network constructed by a biomarker pair for accurate monitoring of colorectal cancer.

Precise and early screening of colorectal cancer (CRC) is one crucial yet challenging task for its treatment, and the analysis of multi-targets of CRC in a single assay with high accuracy is essential for pathological research and clinical diagnosis. Here, a CRC-related biomarker pair, microRNA-211 (miRNA-211) and H2S, was detected by constructing a three-dimensional (3D) ordered DNA network. First, trace amount of miRNA-211 could initiate a hybridization chain reaction-based amplification process. A highly ordered 3D DNA network was formed based on the organized assembly of DNA-cube frameworks that were constructed by DNA origamis and Ag nanoparticles (NPs) encapsulated inside. In the presence of the H2S, Ag NPs within the network can be etched to generate Ag2S quantum dots, which could be better visualized in fluorescence in situ cell imaging. Using the 3D DNA ordered network as the sensing platform, it can acquire dual analysis of biomolecule (miRNA-211) and inorganic gas (H2S) in vitro, overcoming the limitations of single type of biomarker detection in a single assay. This assay achieved a wide linearity range of H2S from 0.05 to 10 µM, and exhibited a low limit of detection of 4.78 nM. This strategy allows us to acquire the spatial distributions of H2S and miRNA expression levels in living CRC cells simultaneously, providing a highly sensitive and selective tool for early screening and monitoring of CRC.

Long non­coding RNA DSCAM­AS1 functions as an oncogene in thyroid cancer via regulating miR­211.

Long non-coding RNA Down syndrome cell adhesion molecule-antisense 1 (DSCAM-AS1) has been reported to play key roles in the progression and initiation of several cancer types. However, the various functional roles of DSCAM-AS1 in thyroid cancer tumorigenesis remain largely elusive. In the present study, the expression of DSCAM-AS1 was examined in thyroid cancer tissues and cell lines. Cell Counting Kit-8, wound healing, Transwell and clonogenic assays were conducted to detect cell proliferation, migration, invasion and colony formation, respectively. The association of DSCAM-AS1 with microRNA 211 (miR-211) was determined by luciferase reporter assay. It was found that the expression of DSCAM-AS1 was upregulated in thyroid cancer cells and tissues. Furthermore, enhanced DSCAM-AS1 expression was positively associated with lymph node metastasis and tumor-node-metastasis stage. Functional experiments demonstrated that DSCAM-AS1 knockdown inhibited the migration, proliferation and invasion of TPC-1 cells. Mechanistically, DSCAM-AS1 could bind to miR-211. Prevention of miR-211 by a miR-211 inhibitor reversed the effect of DSCAM-AS1 depletion in thyroid cancer tumorigenesis. Briefly, the current findings suggested that knockdown of DSCAM-AS1 suppressed the tumorigenesis of thyroid cancer via regulating miR-211, suggesting that DSCAM-AS1 may be a favorable therapeutic target for thyroid cancer.

MicroRNA-211-5p in extracellular vesicles derived from BMSCs facilitates the repair of rat frozen shoulder via regulating KDM2B/LACC1 axis.

OBJECTIVE: This study aims to explore the mechanism of miR-211-5p in extracellular vesicles (EVs) derived from bone marrow mesenchymal stem cells (BMSCs) in improving frozen shoulder (FS) in rat models. METHODS: Rat BMSCs and EVs derived from rat BMSCs were isolated, identified, and then injected into rats to assess the expression of TGF-ß, MMP1, MMP3, MMP12, GAP43, and PGP9.5 in shoulder capsule tissues. The range of motion of bilateral glenohumeral joints was assessed and pathological changes of shoulder capsule tissues were observed after hematoxylin-eosin staining. The binding sites of miR-211-5p to KDM2B and LACC1 to H3K4me3 were measured. FS rat models with LACC1 highly expressed were established to assess the motion of bilateral glenohumeral joints and expression of arthritis related factors in rats. RESULTS: EVs were successfully extracted from BMSCs. Injection of BMSCs-EVs could improve the activity of bilateral glenohumeral joints and the pathological condition of joint capsule in rats. Elevated expression of miR-211-5p was found in rats injected with BMSCs-EVs. Dual luciferase assay showed that miR-211-5p had a binding site with KDM2B. ChIP, qRT-PCR, and western blot experiments showed BMSCs-EVs injection resulted in elevated enrichment of LACC1 promoter in shoulder capsule tissues of FS rats, and decreased mRNA and protein expression of KDM2B and increased H3K4me3 methylation. Overexpression of LACC1 could also improve the pathological condition of joint capsule tissue. CONCLUSION: miR-211-5p in EVs derived from BMSCs increased H3K4me3 methylation in shoulder capsule tissue of rats by binding KDM2B, resulting in up-regulated transcription level of LACC1 and improving FS. AVAILABILITY OF DATA AND MATERIALS: The datasets used or analyzed during the current study are available from the corresponding author on reasonable request.

Relationship between two serum factor levels and collateral circulation formation in elderly patients with coronary heart disease / 中华老年心脑血管病杂志

Objective To investigate the relationship of the expression levels of serum miR-140 and miR-211 in elderly patients with coronary heart disease(CHD)and collateral circulation forma-tion.Methods A total of 151 CHD elderly patients undergoing surgical treatment in our hospital were included as the study subjects,and were divided into non-collateral circulation group(100 cases)and collateral circulation group(51 cases)according to the presence or absence of collateral circulation.RT-qPCR was applied to detect the expression levels of miR-140 and miR-211 in the serum.Results Larger proportions of culprit coronary artery＞3 branches and stenosis ≥75％and higher serum miR-211 level,but lower miR-140 level were observed in the non-collateral cir-culation group than the collateral circulation group(P＜0.01).The number of coronary artery lesions and the severity of coronary artery stenosis were negatively correlated with serum miR-140 level(r=-0.546,P＜0.01;r=-0.562,P＜0.01),and positively with miR-211 level(r=0.539,P＜0.01;r=0.528,P＜0.01).Multivariate logistic regression analysis indicated that miR-140 was a protective factor while miR-211 was an independent risk factor for collateral circulation formation in elderly CHD patients(P＜0.01).The area under the curve of the two indicators com-bined together in predicting collateral circulation formation was 0.896(95％CI:0.834-0.938,P＜0.05).Conclusion Serum miR-140 and miR-211 are both influencing factors for collateral cir-culation formation,and their combination has high predictive value for the formation.

Neuroprotective effects of microRNA-211-5p on chronic stress-induced neuronal apoptosis and depression-like behaviours.

Findings from recent studies have revealed that microRNAs (miRNAs) are related to numerous neurological disorders. However, whether miRNAs regulate neuronal anomalies involved in the pathogenesis of depression remain unclear. In the present study, we screened miRNA expression profiles in the CA1 hippocampus of a rat model of depression and found that a specific miRNA, microRNA-211-5p, was significantly down-regulated in depressed rats. When miR-211-5p was up-regulated in these rats, neuronal apoptosis within the CA1 area was suppressed, effects which were accompanied with an amelioration of depression-like behaviours in these rats. These neuroprotective effects of miR-211-5p in depressed rats appear to result through suppression of the Dyrk1A/ASK1/JNK signalling pathway within the CA1 area. In further support of this proposal are the findings that knock-down of miR-211-5p within the CA1 area of normal rats activated the Dyrk1A/ASK1/JNK pathway, resulting in the promotion of neuronal apoptosis and display of depression-like behaviours in these rats. Taken together, these results demonstrate that deficits in miR-211-5p contribute to neuronal apoptosis and thus depression-like behaviours in rats. Therefore, the miR-211-5p/Dyrk1A pathway may be critically involved in the pathogenesis of depression and serve as a potential therapeutic target for the treatment of depression.

Role of miR-211 in a PC12 cell model of Alzheimer's disease via regulation of neurogenin 2.

NEW FINDINGS: What is the central question of this study? What is the mechanism of miR-211 in an Alzheimer's disease cell model? What is the main finding and its importance? miR-211 was upregulated in an Alzheimer's disease cell model. It targeted neurogenin 2, reduced the activation of the phosphoinositide 3-kinase-Akt signalling pathway, inhibited the proliferation of the Alzheimer's disease cell model and promoted apoptosis. ABSTRACT: MicroRNAs (miRs) are aberrantly expressed in Alzheimer's disease (AD) patients. This study was intended to investigate the effect of miR-211 on an AD cell model and the involvement of neurogenin 2 (Ngn2). The appropriate dose and time for the effect of Aß1-42 on PC12 cells were determined to establish an AD cell model. An effect of miR-211 expression on cell viability, proliferation and apoptosis was detected after cell transfection. Online prediction and a dual luciferase reporter gene assay were utilized to confirm the binding sequence of miR-211 and Ngn2. qRT-PCR and western blot analysis were applied to measure Ngn2 expression. A gain and loss of function assay of miR-211 and Ngn2 was performed, and activation of the phosphoinositide 3-kinase (PI3K)-Akt signaling pathway was detected. The AD cell model was induced by Aß1-42 treatment. miR-211 expression was significantly enhanced after miR-211 transfection, leading to suppressed proliferation and promotion of apoptosis in Aß1-42 -treated PC12 cells. In addition, miR-211 could downregulate Ngn2 mRNA and protein expression, while overexpression of Ngn2 could reverse the effects of miR-211 on Aß1-42 -treated PC12 cells and significantly enhance the phosphorylated Akt and PI3K protein levels. miR-211 could inhibit growth of PC12 cells by suppressing Ngn2 expression and inactivating the PI3K-Akt signalling pathway.

Silenced lncRNA SNHG14 restrains the biological behaviors of bladder cancer cells via regulating microRNA-211-3p/ESM1 axis.

BACKGROUND: Bladder cancer (BCa) is a malignant tumor that occurs on the mucosa of the bladder, in which dysregulated long non-coding RNAs (lncRNAs) are involved. This study investigated the effect of lncRNA small nucleolar RNA host gene 1 (SNHG14) on the biological characteristics of BCa cells from microRNA (miR)-211-3p/ESM1 signaling axis. METHODS: BCa tissues and the matched normal tissues were collected to test SNHG14, miR-211-3p and ESM1 levels. SNHG14, miR-211-3p and ESM1 levels in BCa cell lines (T24, 5637, UMUC-3 and EJ) and normal bladder epithelial cells SV-HVC-1 were detected for screening the cell lines for follow-up experiments. T24 and UMUC-3 cells were transfected with different plasmids of SNHG14, miR-211-3p or ESM1 to observe the biological characteristics of BCa cells by MTT, colony formation, Transwell assays and flow cytometry. Tumor xenograft was implemented to inspect tumor growth in vivo. The targeting relationships of SNHG14, miR-211-3p and ESM1 were verified by bioinformatics software, RNA pull down assay and luciferase reporter assay. RESULTS: Enhanced SNHG14, ESM1 and suppressed miR-211-3p were found in BCa tissues and cells. SNHG14 up-regulated ESM1 via competitive binding with miR-211-3p. Decreased SNHG14 or up-regulated miR-211-3p depressed cell cycle entry, colony formation, invasion, migration and proliferation abilities, and facilitated apoptosis of BCa cells. Decreased SNHG14 or up-regulated miR-211-3p reduced the tumor volume and weight of nude mice with BCa, as well as promoted apoptosis and restrained proliferation of tumor cells. miR-211-3p inhibition or ESM1 overexpression reversed the effects of down-regulation of SNHG14 on BCa, and miR-211-3p up-regulation or ESM1 downregulation reversed the effect of SNHG14 overexpression on BCa. SNHG14 targeted miR-211-3p to regulate ESM1 expression. CONCLUSION: Our study highlights that silenced SNHG14 or elevated miR-211-3p represses the tumorigenic ability of BCa cells, which may be linked to ESM1 knockdown.

Long non­coding RNA TTN­AS1 regulates the proliferation, invasion and migration of triple­negative breast cancer by targeting miR­211­5p.

Increasing evidence has demonstrated that long non­coding RNAs (lncRNAs) serve important roles in numerous malignancies, including triple­negative breast cancer (TNBC). The lncRNA titin­antisense RNA1 (TTN­AS1) has previously been reported to promote tumorigenesis in various types of cancer. The present study aimed to investigate the potential role of TTN­AS1 in breast cancer and the associated underlying mechanisms. Following prediction by Starbase and confirmation by dual­luciferase reporter assay, TINCR was demonstrated to be a target gene for microRNA (miR)­211­5p. The expression levels of TTN­AS1 and miR­211­5p, which was predicted to be targeted by TTN­AS1, in TNBC tissues and in the breast cancer cell lines MDA­MB­453 and MDA­MB­231 were measured using reverse transcription­quantitative PCR. Following TTN­AS1­knockdown, cell proliferation was measured using a Cell Counting Kit­8 assay and colony formation assay, whereas cell invasion and migration were measured using Transwell and wound healing assays, respectively. Luciferase reporter assay was performed to verify the potential interaction between TTN­AS1 and miR­211­5p. In addition, rescue assays were conducted to investigate the effects of TTN­AS1 and miR­211­5p on TNBC development. The results demonstrated that TTN­AS1 expression was significantly upregulated, whereas that of miR­211­5p was found to be downregulated in TNBC tissues and cell lines compared with the matched adjacent normal tissues and normal breast epithelial cell line MCF­10A, respectively. Furthermore, TTN­AS1­knockdown inhibited the proliferation and invasive and migratory abilities of MDA­MB­453 and MDA­MB­231 cells, which was reversed following co­transfection with the miR­211­5p inhibitor. The results from luciferase reporter assay confirmed that miR­211­5p was a direct target of TTN­AS1, suggesting that TTN­AS1 may bind directly to miR­211­5p to negatively regulate its expression. In conclusion, the findings from the present study demonstrated that TTN­AS1 regulated the proliferation and invasive and migratory abilities of TNBC by targeting miR­211­5p. This study may provide some insights into the regulatory mechanism of TNBC and help the development of novel therapeutic interventions for TNBC.

MicroRNA-211-5p attenuates spinal cord injury via targeting of activating transcription factor 6.

The recovery of spinal cord injury (SCI) involves multiple factors, of which miRNAs take an important part. In this study, we evaluated the function of microRNA-211-5p (miR-211-5p) on SCI in a rat model. SCI model was established using modified Allen's weight-drop method and Basso-Bcattie-Bresnahan score was applied to assess the locomotor function. MiR-211-5p agomir was utilized to increase miR-211-5p expression and endoplasmic reticulum (ER) stress inhibitor, 4-PBA (4-phenylbutyric acid), was utilized to suppress ER stress. Neuron apoptosis and the expressions of miR-211-5p, activating transcription factor 6 (ATF6), apoptosis-related proteins, pro-inflammatory cytokines and endoplasmic reticulum stress-related proteins were detected. Dual luciferase reporter gene assay was performed to verify the binding between miR-211-5p and ATF6. The results showed that miR-211-5p directly targeted ATF6. MiR-211-5p was down-regulated and ATF6 was up-regulated in SCI rats. Both interferences with miR-211-5p agomir and 4-PBA effectively attenuated neuron apoptosis and reversed the expressions of apoptosis, inflammation and endoplasmic reticulum stress-related molecules post SCI in rats. These findings demonstrated that miR-211-5p could effectively alleviate SCI-induced neuron apoptosis and inflammation via directly targeting ATF-6 and regulating ER stress.

LINC01315 Impairs microRNA-211-Dependent DLG3 Downregulation to Inhibit the Development of Oral Squamous Cell Carcinoma.

Recent studies have revealed that long non-coding RNAs (lncRNAs) involve in the progression of oral squamous cell carcinoma (OSCC). These lncRNAs have emerged as biomarkers or therapeutic targets for OSCC. We here aimed to investigate the role of lncRNA LINC01315 in OSCC and the related mechanisms. LINC01315 and DLG3 were determined to be poorly expressed while microRNA-211 (miR-211) was highly expressed in OSCC tissues and cells using RT-qPCR and western blot analysis. Based on the results obtained from dual-luciferase reporter gene, RIP, and FISH assays, LINC01315 was found to upregulate DLG3 expression by competitively binding to miR-211. Upon altering the expression of LINC01315, and/or miR-211 in OSCC cells with shRNA, mimic, or an inhibitor, we assessed their effects on OSCC cell proliferation, migration, invasion, and apoptosis. LINC01315 knockdown enhanced OSCC cell proliferation, migration and invasion, but dampened their apoptosis, all of which could be reversed by miR-211 inhibition. Elevation of DLG3, a target gene of miR-211, activated the Hippo signaling pathway, whereby suppressing OSCC progression in vitro. Finally, their roles in tumor growth were validated in vivo. These findings suggest that LINC01315 elevates DLG3 expression by competitively binding to miR-211, thereby suppressing OSCC progression.

Identification of MiR-211-5p as a tumor suppressor by targeting ACSL4 in Hepatocellular Carcinoma.

BACKGROUND: Liver cancer is among the most common malignancy worldwide. Hepatocellular carcinoma (HCC), the principal histological subtype of liver cancer, is globally the third most common cause of cancer-related mortality. The high rates of recurrence and metastasis contribute to the poor prognosis of HCC patients. In recent years, increasing evidence has shown that microRNAs (miRNAs) are involved in the tumorigenesis, progression, and prognosis of HCC. METHODS: To screen for key candidate miRNAs in HCC, three microarray datasets were downloaded from Gene Expression Omnibus (GEO). The sole common differentially expressed miRNA (DEmiR) observed in the above three datasets using a Venn diagram was microRNA-211-5p (miR-211-5p). The expression of miR-211-5p from HCC tissues was measured in several HCC cell lines. Additionally, using Kaplan-Meier plots, the potential prognostic value of miR-211-5p in HCC was analyzed. Cell counting kit-8 (CCK-8) and transwell assays examined the ability of miR-211-5p to induce cell proliferation, migration, and invasion in HCC cultures. The interaction of miR-211-5p and Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) was assessed both theoretically and using a luciferase reporter assay. Finally, the ability of miR-211-5p to modulate tumorigenesis in HCC in vivo was assessed after establishing a xenograft model. RESULTS: qRT-PCR demonstrated that the relative expression of miR-211-5p was considerably down-regulated in HCC tissues and cell lines compared with normal tissue. Kaplan-Meier plots indicated that HCC patients with decreased expression of miR-211-5p had poor overall survival. Upregulation of miR-211-5p in vitro consistently suppressed cell proliferation, migration, and invasion. In contrast, enhanced expression of ACSL4 promoted a malignant phenotype in HCC cells. Importantly, we discovered that ACSL4 was a direct downstream target of miR-211-5p in HCC, and that miR-211-5p suppressed the malignant phenotype by inhibition of ACSL4 expression. Furthermore, miR-211-5p overexpression impaired tumorigenesis and growth of HCC in vivo. CONCLUSIONS: Targeting miR-211-5p and the downstream gene ACSL4 will possibly provide novel insight and represents a promising approach to future therapy of HCC patients.

The function of microRNA-211 expression in post-fracture bone cell apoptosis involving the transforming growth factor-ß/ phosphoinositide 3-kinase signaling pathway.

BACKGROUND: The underlying mechanism of micro (mi)RNA-211 in bone cell apoptosis after fracture remains unclear. This study aimed to determine the effect and function of miRNA-211 in bone cell apoptosis in fracture patients. METHODS: Serum samples were collected from patients with fractures and healthy controls. Serum miR-211 expression was detected by quantitative PCR. MC3T3-E1 cells were transfected with a transforming growth factor (TGF)-ß inhibitor and phosphoinositide 3-kinase (PI3K) inhibitor. The viability of MC3T3-E1 cells was detected by the MTT assay, and apoptosis was detected by flow cytometry. Caspase-3/9 activity and the protein expression of TGF-ß, PI3K, and p-Akt were detected by western blot and immunoprecipitation. RESULTS: In the fracture group, miRNA-211 expression was significantly up-regulated compared with controls. We used miRNA-211 mimics to up-regulate miRNA-211 expression, and observed inhibited cell viability and induced apoptosis and lactate dehydrogenase (LDH) activity. miRNA-211 up-regulation also suppressed the expression of TGF-ß, PI3K, and p-Akt proteins. Conversely, miRNA-211 down-regulation increased cell viability and reduced apoptosis and LDH activity, as well as inducing the expression of TGF-ß, PI3K, and p-Akt. Inhibiting TGF-ß decreased the effect of anti-miRNA-211 on osteocyte apoptosis. CONCLUSION: Our data indicate that miRNA-211 functions via the TGF-ß/PI3K/Akt signaling pathway in patients with fractures.

miR-211 alleviates ischaemia/reperfusion-induced kidney injury by targeting TGFßR2/TGF-ß/SMAD3 pathway.

MicroRNA-211 (miR-211) is closely related to apoptosis and plays an important role in ischemia/reperfusion (I/R) injury. Whether miR-211 is involved in the protective effects in renal I/R injury is unknown. In this study, we evaluated the role of miR-211 in human tubular epithelial cells in response to hypoxia-reoxygenation (H/R) stimulation and I/R injury in vitro and in vivo. The results revealed that miR-211 was down-regulated and TGFßR2 was up-regulated in human kidney (HK-2) cells subjected to H/R. Luciferase reporter assay showed that TGFßR2 was a direct target of miR-211. Enforced miR-211 expression decreased H/R-induced HK-2 cell apoptosis and increased cell viability, and targeting miR-211 further increased H/R-induced HK-2 cell apoptosis and decreased cell viability. However, the effect of miR-211 was reversed by targeting TGFßR2 or enforced TGFßR2 expression in miR-211 overexpressing cells or miR-211 downexpressing cells. Moreover, we confirmed that miR-211 interacted with TGFßR2, and regulating TGF-ß/SMAD3 signal. In vivo in mice, miR-211 overexpression ameliorates biochemical and histological kidney injury, reduces apoptosis in mice following I/R. On the contrary, miR-211 downexpressing promoted histological kidney injury and increased apoptosis in mice following I/R. Inhibition of miR-211 or miR-211 overexpression inhibited TGF-ß/SMAD3 pathways or activated TGF-ß/SMAD3 signal pathways in vitro and in vivo, which are critical for cell survival. Our findings suggested that miR-211 suppress apoptosis and relieve kidney injury following H/R or I/R via targeting TGFßR2/TGF-ß/SMAD3 signals. Therefore, miR-211 may be as therapeutic potential for I/R- induced kidney injury.

Long non-coding RNA F11-AS1 inhibits HBV-related hepatocellular carcinoma progression by regulating NR1I3 via binding to microRNA-211-5p.

Long non-coding RNAs (lncRNAs) could regulate growth and metastasis of hepatocellular carcinoma (HCC). In this study, we aimed to investigate the mechanism of lncRNA F11-AS1 in hepatitis B virus (HBV)-related HCC. The relation of lncRNA F11-AS1 expression in HBV-related HCC tissues to prognosis was analysed in silico. Stably HBV-expressing HepG2.2.15 cells were established to explore the regulation of lncRNA F11-AS1 by HBx protein, as well as to study the effects of overexpressed lncRNA F11-AS1 on proliferation, migration, invasion and apoptosis in vitro. Subsequently, the underlying interactions and roles of lncRNA F11-AS1/miR-211-5p/NR1I3 axis in HBV-related HCC were investigated. Additionally, the influence of lncRNA F11-AS1 and miR-211-5p on tumour growth and metastasis capacity of HepG2.2.15 cells were studied on tumour-bearing nude mice. Poor expression of lncRNA F11-AS1 was correlated with poor prognosis in patients with HBV-related HCC, and its down-regulation was caused by the HBx protein. lncRNA F11-AS1 was proved to up-regulate the NR1I3 expression by binding to miR-211-5p. Overexpression of lncRNA F11-AS1 reduced the proliferation, migration and invasion, yet induced apoptosis of HepG2.2.15 cells in vitro, which could be abolished by overexpression of miR-211-5p. Additionally, either lncRNA F11-AS1 overexpression or miR-211-5p inhibition attenuated the tumour growth and metastasis capacity of HepG2.2.15 cells in vivo. Collectively, lncRNA F11-AS1 acted as a modulator of miR-211-5p to positively regulate the expression of NR1I3, and the lncRNA F11-AS1/miR-211-5p/NR1I3 axis participated in HBV-related HCC progression via interference with the cellular physiology of HCC.