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Background: To explore the effect and mechanism of action of miR-210 on postmenopausal osteoporosis (PMPO) in ovariectomized rats in vivo., Methods: An ovariectomized (OVX) rat model was established by ovariectomy. Tail vein injection was performed to overexpress and knock down miR-210 in OVX rats, followed by the collection of blood and femoral tissues from each group of rats. And quantitative real-time polymerase chain reaction (qRT-PCR) was applied to assess the expression level of miR-210 in femoral tissues of each group. Micro computed tomography (Micro CT) was adopted to scan the microstructure of the femoral trabecula in each group to obtain relevant data like bone mineral density (BMD), bone mineral content (BMC), trabecular bone volume fraction (BV/TV), trabecular thickness (Tb.Th), bone surface-to-volume ratio (BS/BV), and trabecular separation (Tb.Sp). ELISA was used for determining the level of bone alkaline phosphatase (BALP), amino-terminal propeptide of type I procollagen (PINP), osteocalcin (OCN), and C-terminal telopeptide of type I collagen (CTX-1) in serum; and Western blot for the protein level of Runt-related transcription factor 2 (Runx2), osteopontin (OPN), and collagen type I alpha 1 (COL1A1) in femoral tissues., Results: MiR-210 expression was significantly decreased in femoral tissues of OVX rats. Overexpression of miR-210 could obviously increase BMD, BMC, BV/TV and Tb.Th, whereas significantly decrease BS/BV and Tb.Sp in femurs of OVX rats. Moreover, miR-210 also downregulated BALP and CTX-1 level, upregulated PINP and OCN level in the serum of OVX rats promoted the expression of osteogenesis-related markers (Runx2, OPN and COL1A1) in the femur of OVX rats. Additionally, further pathway analysis revealed that high expression of miR-210 activated the vascular endothelial growth factor (VEGF)/Notch1 signaling pathway in the femur of OVX rats., Conclusion: High expression of miR-210 may improve the micromorphology of bone tissue and modulate bone formation and resorption in OVX rats by activating the VEGF/Notch1 signaling pathway, thereby alleviating osteoporosis. Consequently, miR-210 can serve as a biomarker for the diagnosis and treatment of osteoporosis in postmenopausal rats., (© 2023. The Author(s).)

Introduction: Identifying neoadjuvant chemotherapy (NAC) response in patients with muscle invasive bladder cancer (MIBC) has had limited success based on clinicopathological features and molecular subtyping. Identification of chemotherapy responsive cohorts would facilitate delivery to those most likely to benefit., Objective: Develop a molecular signature that can identify MIBC NAC responders (R) and non-responders (NR) using a cohort of known NAC response phenotypes, and better understand differences in molecular pathways and subtype classifications between NAC R and NR., Materials and Methods: Presented are the messenger RNA (mRNA) and microRNA (miRNA) differential expression profiles from initial transurethral resection of bladder tumor (TURBT) specimens of a discovery cohort of MIBC patients consisting of 7 known NAC R and 11 NR, and a validation cohort consisting of 3 R and 5 NR. Pathological response at time of cystectomy after NAC was used to classify initial TURBT specimens as R (pT0) versus NR (≥pT2). RNA and miRNA from FFPE blocks were sequenced using RNAseq and qPCR, respectively., Results: The discovery cohort had 2309 genes, while the validation cohort had 602 genes and 13 miRNA differentially expressed between R and NR. Gene set enrichment analysis identified mitochondrial gene expression, DNA replication initiation, DNA unwinding in the R discovery cohort and positive regulation of vascular associated smooth muscle cell proliferation in the NR discovery cohort. Canonical correlation (CC) analysis was applied to differentiate R versus NR. 3 CCs (CC13, CC16, and CC17) had an AUC >0.65 in the discovery and validation dataset. Gene ontology enrichment showed CC13 as nucleoside triphosphate metabolic process, CC16 as cell cycle and cellular response to DNA damage, CC17 as DNA packaging complex. All patients were classified using established molecular subtypes: Baylor, UNC, CIT, Lund, MD Anderson, TCGA, and Consensus Class. The MD Anderson p53-like subtype, CIT MC4 subtype and Consensus Class stroma rich subtype had the strongest correlation with a NR phenotype, while no subtype had a strong correlation with the R phenotype., Conclusions: Our results identify molecular signatures that can be used to differentiate MIBC NAC R versus NR, salient molecular pathway differences, and highlight the utility of molecular subtyping in relation to NAC response.

Schizophrenia is a polygenetic disease, the heterogeneity of which is likely complicated by epigenetic modifications yet to be elucidated. Here, we performed transcriptomic analysis of peripheral blood RNA from monozygotic twins discordant for schizophrenia and identified a schizophrenia-associated down-regulated microRNA, miR-501-3p. We showed that the loss of miR-501-3p in germline knockout (KO) male mice resulted in dendritic structure defects, glutamatergic transmission enhancement, and sociability, memory, and sensorimotor gating disruptions, which were attenuated when miR-501 expression was conditionally restored in the nervous system. Combining the results of proteomic analyses with the known genes linked to schizophrenia revealed that metabotropic glutamate receptor 5 (mGluR5) was one of the miR-501-3p targets and was elevated in vivo upon loss of miR-501. Treatment with the mGluR5 negative allosteric modulator 3-2((-methyl-4-thiazolyl) ethynyl) pyridine or the N -methyl-d-aspartate receptor antagonist 2-amino-5-phosphonopentanoic acid ameliorated the deficits observed in Mir501 -KO mice. The epigenetic and pathophysiological mechanism that links miR-501-3p to the modulation of glutamatergic transmission provides etiological implications for schizophrenia.

Background: Allergic rhinitis (AR) is an allergic disease of nasal mucosa. LncRNAs are key modulators affecting AR development. Neverthelss, the impact of lncRNA ANRIL in AR is not clear., Objective: This work decided to study the mechanism underlying the impact of ANRIL on TLR4 expression through targeting miR-16-5p during autophagy and epithelial barrier dysfunction in the progression of AR., Methods: Human nasal epithelial cells were exposed to TNF-α to establish AR cell model, AR mice model was constructed by ovalbumin (OVA) treatment. QRT-PCR or western blot assays were applied to measure the levels of mRNA and proteins. Dual-luciferase reporter gene detection and RIP assay were conducted to verify the association between ANRIL and miR-16-5p. Autophagy flux assessment by mRFP-GFP-LC3 method was performed to detect autophagy level., Results: AR progression could induce the autophagy, and the expressions of tight junction proteins were downregulated in AR cell model. Moreover, knockdown of ANRIL reversed the effect of AR on autophagy-related protein and tight junction proteins MiR-16-5p was found to be bound with ANRIL and miR-16-5p inhibitor could reverse ANRIL knockdown-induced downregulation of autophagy-related proteins and epithelial barrier dysfunction. In addition, miR-16-5p directly targeted TLR4. Furthermore, knockdown of ANRIL reversed miR-16-5p and TLR4 expression, autophagy level, and tight junction protein levels in nasal mucosa of AR mice., Conclusion: This study illustrated that ANRIL acted as a promotion factor in AR induced autophagy and epithelial barrier dysfunction by enhancing the expression of TLR4 via interacting with miR-16-5p., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

This study explored the regulation of different perfusion methods on ischemia-reperfusion injury in donor kidneys. In this study, renal cortical/medullary tissue specimens were collected from porcine kidneys donors using different perfusion methods at various time points. Hematoxylin and eosin (H&E) staining was used to test the histological differences. Differentially expressed micro-ribonucleic acids (miRNAs) were identified by miRNA transcriptome sequencing. Reverse transcription-polymerase chain reaction (RT-PCR) tests were used to verify the changes in miRNAs in the kidney tissue taken from different perfusion groups. The related signaling pathways and the changes in the cell functions of different perfusion groups were analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) /Gene Ontology (GO) bioinformatics analyses. The effects of miRNA overexpression on the metabolism and proliferation of HK2 cells were detected by ATP kit and MTT assay. The H&E staining results showed that there were essentially no differences in the tissue samples among different perfusion groups at and before 12 h compared with a control group. The quantitative PCR results revealed that there was essentially no change in the expression of ssc-miR-451, ssc-miR-1285, and ssc-miR-486 in the cis infusion or joint infusion kidney groups, and their expression was significantly down-regulated over time in the trans-infusion kidney group. The bioinformatics analysis showed that the cellular component, molecular function, and biological processes of the kidney tissue, which had been perfused using three methods, had been consistently affected. The most significant changes after perfusion occurred in the intracellular metabolism signaling pathways. Furthermore, the energy metabolism and proliferation of the HK2 cells were significantly inhibited after the overexpression of miR-451. Specific miRNA markers, such as miR-451, may play a negative regulatory role in cell metabolism following the perfusion of kidney transplants using different methods.

Aim: Pre-eclampsia is a serious pregnancy-specific disease with an incidence of 9.4%. MicroRNAs play a key role in regulating factors in pre-eclampsia, but related research is still limited. This study aims to reveal the role and potential mechanisms of miR-483 in pre-eclampsia., Methods: miR-483 was detected in venous blood, umbilical cord blood and placental tissue of pre-eclampsia patients by Real-time Quantitative polymerase chain reaction (qRT-PCR). Insulin-like growth factor (IGF1) and miR-483 were detected by qRT-PCR and western blot in endothelial progenitor cells isolated from fetal umbilical cord blood. miR-483 was overexpressed and inhibited to detect changes of IGF1 and PI3K/Akt/mTOR pathway in endothelial progenitor cells by qRT-PCR and western blot., Results: miR-483 was downregulated in venous blood, umbilical cord blood and placental tissue of pre-eclampsia patients. In endothelial progenitor cells, overexpression of miR-483 inhibited the expression of IGF1, and inhibition of miR-483 promoted the expression of IGF1. miR-483 regulates the expression of PI3K, Akt, and mTOR in endothelial progenitor cells., Conclusion: miR-483 is downregulated in pre-eclampsia and regulates endothelial progenitor cells by targeting IGF1. miR-483 is a potential alternative for diagnosing and treating pre-eclampsia., (© 2020 Japan Society of Obstetrics and Gynecology.)

Background: The dysregulation of proliferation and apoptosis plays a significant role in the pathogenesis of postmenopausal osteoporosis (PO). MicroRNAs play an important role in regulating apoptosis of MC3T3-E1 cells. However, the role and potential mechanism of miR-708 for regulating H 2 O 2 -induced apoptosis is unknown. This study aimed to investigate the protective function of miR-708 in H 2 O 2 -induced apoptosis of MC3T3-E1 osteoblasts., Methods: MC3T3-E1 was co-cultured with H 2 O 2 for 8 h, then, flow cytometry, malondialdehyde (MDA), and glutathione peroxidase (Gpx) levels were measured to establish the oxidative model. MiRNA microarray was performed to assess differentially expressed miRNAs between control and H 2 O 2 -treated MC3T3-E1 cells. We then performed RT-PCR to identify the relative expression of miR-708 and PTEN. After transfected MC3T3-E1 with miR-708 mimics, flow cytometry, MDA, and Gpx level were performed to identify the apoptosis rate and oxidative stress in these groups. Furthermore, we small interfering RNA of PTEN to identify the role of PTEN in H 2 O 2 -induced apoptosis of MC3T3-E1 cells., Results: H 2 O 2 (100 nM) could significantly induce the apoptosis of MC3T3-E1 cells. Moreover, H 2 O 2 could significantly increase the MDA level and downregulated Gpx level. RT-PCR found that H 2 O 2 significantly decrease the level of miR-708. Compared with H 2 O 2 group, H 2 O 2 + miR-708 mimic significantly decreased the apoptosis rate., Conclusions: miR-708 plays a protective role in H 2 O 2 -induced MC3T3-E1 osteoblasts apoptosis and its protective effect is proceeded by regulating ROS level and PTEN expression level.

Sustained dexamethasone (Dex) treatment could induce secondary osteoporosis, osteonecrosis, or even bone fractures. Dex can induce potent cytotoxicity in cultured human osteoblasts. The aim of this study was to test the potential role of microRNA-7 (miR-7), which targets the epidermal growth factor receptor (EGFR), in Dex-treated human osteoblasts. In OB-6, hFOB1.19, and primary human osteoblasts, miR-7 depletion by a lentiviral antagomiR-7 construct (LV-antagomiR-7) increased EGFR expression and downstream Akt activation, protecting cells from Dex-induced viability reduction, cell death, and apoptosis. In contrast, forced overexpression of miR-7 by a lentiviral miR-7 construct (LV-miR-7) inhibited EGFR expression and Akt activation, potentiating Dex-induced cytotoxicity in OB-6, hFOB1.19, and primary human osteoblasts. EGFR is the primary target of miR-7 in human osteoblasts. Luciferase activity of the EGFR 3-untranslated region was enhanced by LV-antagomiR-7, but decreased by LV-miR-7 in OB-6 cells. Further, LV-antagomiR-7-induced osteoblast cytoprotection against Dex was abolished by the EGFR inhibitors AG1478 and PD153035. Moreover, neither LV-antagomiR-7 nor LV-miR-7 was functional in EGFR-KO OB-6 cells. We also show that miR-7 is upregulated in the necrotic femoral head tissues of Dex-administered patients, correlating with EGFR downregulation. Together, we conclude that miR-7 inhibition protects human osteoblasts from Dex via activation of EGFR signaling.

Background: Diabetic retinopathy (DR) is currently the leading cause of blindness and visual disability in adults with diabetes mellitus (DM). Neovascularization has been identified as an important clinical property in DR, however, the exact mechanisms in DR neovascularization are still unclear and need further elucidation. Methods: Quantitative real-time PCR (qRT-PCR) was conducted to detect the expression level of long non-coding RNA (lncRNA)-metastasis associated lung adenocarcinoma transcript 1 (MALAT1), miR-125b and vascular endothelial-cadherin (VE-cadherin) in human retina microvascular endothelial cells (hRMECs) treated with high glucose (HG). Luciferase assay was used to detect interaction of MALAT1 with miR-125b and miR-125b with VE-cadherin. MTT assay, transwell assay, tube formation assay and vascular permeability assay were conducted to detect the cell viability, migration tube formation ability and permeability of hRMECs, respectively. ELISA was used to examine the release of VE-cadherin and vascular endothelial growth factor (VEGF). Western blotting was used to access the protein expression of VE-cadherin, VEGF, β-catenin, matrix metalloproteinase (MMP) 2 (MMP2) and MMP9. Results: MALAT1 and VE-cadherin were up-regulated while miR-125b was down-regulated in hRMECs treated with HG. MALAT1 could competitively bind to miR-125b against VE-cadherin at the site of 3'-untranslated region (3'-UTR), leading to the up-regulation of VE-cadherin. Knockdown of MALAT1 inhibited the proliferation, migration, tube formation and vascular permeability of hRMECs induced by HG through up-regulating miR-125b. Furthermore, we found the deletion of MALAT1 suppressed the VE-cadherin/β-catenin complex and neovascularization related proteins expression, which was up-regulated by HG. Conclusion: Knockdown of MALAT1 inhibited cell proliferation, migration and angiogenesis of hRMECs via suppressing the VE-cadherin/β-catenin complex through targeting miR-125b. Inhibition of MALAT1 may serve as a potential target for anti-angiogenic therapy for DR., (© 2019 The Author(s).)

Background: Cancer associated fibroblasts (CAFs) are key stroma cells that play dominant roles in tumor progression. However, the CAFs-derived molecular determinants that regulate colorectal cancer (CRC) metastasis and chemoresistance have not been fully characterized., Methods: CAFs and NFs were obtained from fresh CRC and adjacent normal tissues. Exosomes were isolated from conditioned medium and serum of CRC patients using ultracentrifugation method and ExoQuick Exosome Precipitation Solution kit, and characterized by transmission electronic microscopy, nanosight and western blot. MicroRNA microarray was employed to identify differentially expressed miRNAs in exosomes secreted by CAFs or NFs. The internalization of exosomes, transfer of miR-92a-3p was observed by immunofluorescence. Boyden chamber migration and invasion, cell counting kit-8, flow cytometry, plate colony formation, sphere formation assays, tail vein injection and primary colon cancer liver metastasis assays were employed to explore the effect of NFs, CAFs and exosomes secreted by them on epithelial-mesenchymal transition, stemness, metastasis and chemotherapy resistance of CRC. Luciferase report assay, real-time qPCR, western blot, immunofluorescence, and immunohistochemistry staining were employed to explore the regulation of CRC metastasis and chemotherapy resistance by miR-92a-3p, FBXW7 and MOAP1., Results: CAFs promote the stemness, epithelial-mesenchymal transition (EMT), metastasis and chemotherapy resistance of CRC cells. Importantly, CAFs exert their roles by directly transferring exosomes to CRC cells, leading to a significant increase of miR-92a-3p level in CRC cells. Mechanically, increased expression of miR-92a-3p activates Wnt/β-catenin pathway and inhibits mitochondrial apoptosis by directly inhibiting FBXW7 and MOAP1, contributing to cell stemness, EMT, metastasis and 5-FU/L-OHP resistance in CRC. Clinically, miR-92a-3p expression is significantly increased in CRC tissues and negatively correlated with the levels of FBXW7 and MOAP1 in CRC specimens, and high expression of exosomal miR-92a-3p in serum was highly linked with metastasis and chemotherapy resistance in CRC patients., Conclusions: CAFs secreted exosomes promote metastasis and chemotherapy resistance of CRC. Inhibiting exosomal miR-92a-3p provides an alternative modality for the prediction and treatment of metastasis and chemotherapy resistance in CRC.

Objective: Allergic rhinitis (AR) is a chronic inflammatory disease. This study aimed to investigate the role of microRNA-155 (miR-155) in type-2 innate lymphoid cells (ILC2s) on AR., Patients and Methods: Nasal mucosa tissues and peripheral blood samples were collected. mRNA expression of miR-155, interleukin-25 (IL-25), and interleukin-33 (IL-33) in nasal mucosa tissues was determined using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The AR model was established by injecting with murine IL-33. The frequency of ILC2s was quantified using flow cytometry. MiR-155 agomir or antagomir was intranasally administrated to mice. MiR-155 and helper T cell 2 (Th2) cytokines were measured with quantitative Real-time PCR (qRT-PCR), enzyme-linked immunosorbent assay (ELISA) or Western blotting, respectively. Hematoxylin and eosin (HE) staining was used for the histopathological examination., Results: Compared with controls, mRNA levels miR-155 (p<0.001), IL-25 (p<0.05), and IL-33 (p<0.001) were increased in nasal mucosa tissues of AR patients and AR mice, and ILC2s ratios were enhanced in human peripheral blood (p<0.0001), which were much higher after intranasal administration with miR-155 agomir (p<0.0001). MiR-155 expression of AR mice was significantly reduced after intranasal administration with miR-155 antagomir (p<0.05). Frequencies of ILC2s in human peripheral blood significantly correlated with miR-155 (r=0.4803, p=0.0130). MiR-155 up-regulation markedly increased frequencies of nasal rubbing/sneezing and levels of IL-4, IL-5, IL-9, and IL-13. Pathological changes were worsened after miR-155 agomir and ameliorated after miR-155 antagomir administration. MiR-155 agomir mice (p<0.001) showed higher ILC2s, whereas lower in miR-155 antagomir mice compared to AR mice (p<0.05)., Conclusions: MiR-155 played critical effects on Th2 factor expression and allergic inflammatory response in ILC2 cells in AR.

Melanoma develops from pigment-producing melanocytes in the epidermis, and is the most common type of skin cancer. Because of the lack of effective therapies, the median survival of patients developing metastatic melanoma is less the 1 year. In this paper, we studied the oncogenic role of miR-135b in melanoma cells. We compared the miR-135b levels in 20 melanoma tissues in reference to their corresponding nontumor regions. Next, we studied the impact of miR-135b or its inhibitor on cell proliferation, migration, or apoptosis in either primary melanocytes or the melanoma cell line, respectively. Finally, we validated large tumor suppressor kinase 2 (LATS2) as the downstream target of miR-135b in a luciferase reporter assay, western blotting analysis, and knockdown study in primary melanocytes. MiR-135b expression was significantly upregulated in melanoma tissue. Overexpressing miR-135b in primary melanocytes promoted cell proliferation and migration. In contrast, inhibition of miR-135b expression suppressed the growth and metastasis of A-375 cells and enhanced cell apoptosis. LATS2 was confirmed as the target of miR-135b. Knockdown of LATS2 in melanocytes also promoted cell growth, but not cell invasion potential. Our findings showed miR-135b as a novel oncogene in melanoma tumorigenesis. The oncogenic mechanism may involve the downregulation of LATS2.

Objective: Mounting evidence has suggested that microRNAs (miRNAs) play crucial roles in the progression of nasopharyngeal carcinoma (NPC). However, the molecular mechanism remains not fully understood. We aimed to examine the expression and biological function of miR-122-5p in NPC., Materials and Methods: Quantitative Real Time-Polymerase Chain Reaction was conducted to examine the expression of miR-122-5p. Cell Counting Kit-8 assay, colony formation assay, wound healing assay and transwell assay were performed to measure cell proliferation, colony formation, migration and invasion. Luciferase reporter assay and Western blot assay were used to confirm the target gene of miR-122-5p., Results: The results showed that miR-122-5p was significantly downregulated in NPC cell lines. Additionally, it was demonstrated that special AT-rich sequence-binding protein 1 (SATB1) was targeted by miR-122-5p. Furthermore, our results revealed that miR-122-5p inhibits cell proliferation, colony formation, cell migration and cell invasion by targeting SATB1., Conclusions: Our data suggested that miR-122-5p functions as a tumor suppressor and may be a therapeutic target for NPC.

Objective: A comprehensive review of the network regulation of exosomes and microRNAs (miRNAs) in neurodegenerative diseases was done, centering on the mechanism of the formation of exosomes and miRNAs and the sorting mechanism of exosomal miRNAs, with the aim to provide a theoretical basis in the search of biomarkers and the treatment of neurodegenerative diseases., Data Sources: The comprehensive search used online literature databases including NCBI PubMed, Web of Science, Google Scholar, and Baidu Scholar., Study Selection: The study selection was based on the following keywords: exosomes, miRNAs, central nervous system (CNS), and neurodegenerative diseases. The time limit for literature retrieval was from the year 2000 to 2018, with language restriction in English. Relevant articles were carefully reviewed, with no exclusions applied to study design and publication type., Results: Exosomes are the smallest nanoscale membranous microvesicles secreted by cells and contain important miRNAs, among other rich contents. In the CNS, exosomes can transport amyloid β-protein, α-synuclein, Huntington-associated protein 1, and superoxide dismutase I to other cells. These events relieve the abnormal accumulation of proteins and aggravating neurological diseases. In some neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, miRNAs are pathologically altered as an inexorable course, suggesting that miRNAs may contribute neurodegeneration. Exosomes and miRNAs form a network to regulate the homeostasis of the CNS, both synergistically and individually., Conclusion: The network of exosomes and miRNAs that regulates CNS homeostasis is a promising biomarker for the diagnosis and treatment of neurodegenerative diseases., Competing Interests: There are no conflicts of interest

MicroRNAs (miRNAs), a class of short, single‑stranded non‑coding RNAs, regulate and control gene expression in eukaryotes by degrading mRNA at the post‑transcriptional level. Regulation by miRNAs involves a plethora of biological processes, such as cell differentiation, proliferation, metastasis, metabolism, apoptosis, tumorigenesis and others. miRNAs also represent a powerful tool in disease diagnosis and prognosis. The miR‑17‑92 cluster, one of the most extensively investigated microRNA clusters, comprises six mature miRNA members, including miR‑17, miR‑18a, miR‑19a, miR‑19b, miR‑20a and miR‑92a. Originally identified as being involved in tumorigenesis, it is currently evident that the expression of the miR‑17‑92 cluster is upregulated in a wide range of tumor cells and cancer types; thus, this cluster has been identified as a potential oncogene. Considering the growing interest in the field of miR‑17‑92 research, we herein review recent advances in the expression and regulation of this cluster in various cancer cells, discuss the proposed mechanism of action for tumorigenesis and tumor development, and propose clinical and therapeutic applications for miR‑17‑92 cluster members, such as potential cancer biomarkers.

F-box proteins are critical components of the SKP1-CUL1-F-box (SCF) E3 ubiquitin ligases and involved in the ubiquitin-dependent proteolytic pathway. Dysregulation of F-box protein-mediated proteolysis often leads to human malignancies. F-box only protein 8 (FBX8), a novel component of F-box proteins, is down-regulated in several tumors and closely correlates with tumor progression. However, little is known about its function, regulatory mechanisms and substrates in the progression of colorectal carcinoma (CRC). Combining microRNA (miRNA) assay, functional characterization, mechanistic studies with clinical validation, we identify FBX8 as a CRC metastasis suppressor downstream of miR-223, a metastasis promoting miRNA that is transcriptionally regulated by Myocyte enhancer factor (MEF2A). mTOR is a substrate of FBX8 for ubiquitin-mediated degradation and is required for FBX8 induced cell proliferation and invasion in CRC cells. FBX8 is down-regulated in human CRC tissues and correlates with MEF2A, miR-223 and mTOR expression levels. Notably, low FBX8 expression status in CRC tissues was a significant prognostic factor for poor overall survival of patients. These findings illustrate FBX8 as a metastasis suppressor that functions through mTOR signaling pathway and has significant prognostic power., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

AMP-activated protein kinase (AMPK) activation could protect osteoblasts from dexamethasone (Dex). This study aims to provoke AMPK activation via microRNA downregulation of its negative regulator protein kinase C ζ (PKCζ). Results show that microRNA-25-5p (miR-25-5p) targets PKCζ's 3' untranslated regions (UTRs). Forced-expression of miR-25 downregulated PKCζ and activated AMPK in human osteoblastic cells (OB-6 and hFOB1.19 lines), which thereafter protected cells from Dex. Reversely, expression of antagomiR-25, the miR-25 inhibitor, upregulated PKCζ and inhibited AMPK activation, exacerbating Dex damages. Notably, PKCζ shRNA knockdown similarly activated AMPK and protected osteoblastic cells from Dex. AMPK activation was required for miR-25-induced osteoblastic cell protection. AMPKα shRNA or dominant negative mutation almost completely blocked miR-25-induced cytoprotection against Dex. Further studies showed that miR-25 expression increased NADPH activity and suppressed Dex-induced oxidative stress in osteoblastic cells. Such effects by miR-25 were abolished with AMPKα knockdown or mutation. Significantly, miR-25-5p level was increased in patients' necrotic femoral head tissues, which was correlated with PKCζ downregulation and AMPK hyper-activation. These results suggest that miR-25-5p targets PKCζ and protects osteoblastic cells from Dex possibly via activating AMPK signaling.

BACKGROUND The aim of this study was to investigate the diagnostic and prognostic value of microRNA (miRNA)-21, miRNA-23a, and miRNA-125b in Burkitt lymphoma (BL) in children. MATERIAL AND METHODS We recruited 41 children with BL for the case group, 56 children with lymph node inflammation for the positive control group, and 60 healthy children for the negative control group. Real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was conducted for detection of circulating miRNA-21, miRNA-23a, and miRNA-125b. A receiver operating characteristic (ROC) curve was drawn to compare the diagnostic value of miRNA-21, miRNA-23a, and miRNA-125b. Kaplan-Meier method and log-rank test were used for prognostic analyses. RESULTS MiRNA-21 and miRNA-23a had significantly higher expression in cases than in positive and negative controls (all P<0.05). Overexpression of miRNA-21 and miRNA-23a were associated with staging, WBC, upregulated serum lactate dehydrogenase (LDH) level, presence of lymphoma size ≥6 cm, and cluster of differentiation 10 (CD10) expression, while miRNA-125b expression had an association with staging and upregulated serum LDH level (both P<0.05). ROC curves of miRNA-21, miRNA-23a, and miRNA-125b presented an area under curve (AUC) of 0.759, 0.853 and 0.615, respectively. MiRNA-21 and miRNA-23a in combination had an AUC of 0.869. After treatment, both miRNA-21 and miRNA-23a expression were significantly decreased (both P<0.05). Advanced clinical stage, upregulated LDH, and lymphoma size of ³6 cm were related to low complete remission rate (all P<0.05). CONCLUSIONS Patients with high expression of miRNA-21 and miRNA-23a had significantly lower complete remission rates and survival rates than those with low expression. Expression of miRNA-21 and miRNA-23a may serve as useful diagnostic and prognostic biomarkers in children with BL.

Background: MiR-214 is aberrantly regulated in several tumours, but its underlying mechanisms in colorectal cancer (CRC) metastasis remain largely unknown. This study aimed to demonstrate the function and potential mechanism of miR-214 in regulating invasion and metastasis of CRC., Methods: The transcription factor and targets of miR-214 were predicted by bioinformatics and validated using ChIP and dual-luciferase reporter assay. DNA methylation status was explored using bisulphite sequencing PCR. The in vitro and in vivo function of miR-214 in CRC was evaluated using MTT, plate colony formation, Matrigel invasion and animal models. Real-time PCR or western blotting was performed to detect FOXD3, miR-214 and MED19 expressions in CRC cells and clinical specimens., Results: MiR-214 was downregulated in CRC and was significantly correlated with lymphatic metastasis. Downregulation of miR-214 might due to promoter hypermethylation in CRC. FOXD3 was validated as a transcription factor of miR-214 by ChIP assay. Dual-luciferase assay identified MED19 as a target of miR-214 in CRC. In vitro and in vivo experiments showed that miR-214 mediated the inhibiting effect of FOXD3 on proliferation, invasion and metastasis by targeting MED19. Spearman's correlation analysis showed a positive correlation between FOXD3 and miR-214, and negative correlations between FOXD3 and MED19, miR-214 and MED19 in CRC cells and clinical specimens., Conclusions: FOXD3/miR-214/MED19 axis is important for the regulation of growth, invasion and metastasis of CRC. Targeting the miR-214-mediated axis might be helpful for the treatment of CRC.

Activation of AMP-activated protein kinase (AMPK) could potently protect osteoblasts/osteoblastic cells from dexamethasone (Dex). We aim to induce AMPK activation via microRNA ("miRNA") downregulation of its phosphatase Ppm1e. We discovered that microRNA-135b ("miR-135b") targets the 3' untranslated regions (UTRs) of Ppm1e. In human osteoblasticOB-6 cells and hFOB1.19 cells, forced-expression of miR-135b downregulated Ppm1e and activated AMPK signaling. miR-135b also protected osteoblastic cells from Dex. shRNA-induced knockdown of Ppm1e similarly activated AMPK and inhibited Dex-induced damages. Intriguingly, in the Ppm1e-silenced osteoblastic cells, miR-135b expression failed to offer further cytoprotection against Dex. Notably, AMPK knockdown (via shRNA) or dominant negative mutation abolished miR-135b-induced AMPK activation and cytoprotection against Dex. Molecularly, miR-135b, via activating AMPK, increased nicotinamide adenine dinucleotide phosphate (NADPH) activity and inhibited Dex-induced oxidative stress. At last, we found that miR-135b level was increased in human necrotic femoral head tissues, which was correlated with Ppm1e downregulation and AMPK activation. There results suggest that miR-135b expression downregulates Ppm1e to activate AMPK signaling, which protects osteoblastic cells from Dex.

Objective: In this work, we aimed to study whether myocardial infarction associated transcript (MIAT) exerts a regulative effect on cardiac hypertrophy via acting as a miR-150 sponge., Materials and Methods: Cardiac hypertrophy was induced using Angiotensin II (Ang II). MIAT and miR-150 expression were quantified using qRT-PCR. Rat heart-derived H9c2 cells were used as the in vitro model. Cardiac hypertrophic features were assessed by quantifying cardiac hypertrophic genes and measurement of cell surface, protein synthesis and total protein content., Results: MIAT is significantly increased in Ang II induced cardiac hypertrophy in a mouse model and in H9c2 cells. MIAT siRNA substantially alleviated the Ang II induced upregulation of ANP, BNP and β-MHC in H9c2 cells and markedly attenuated the Ang II induced increase of the cell surface area and the protein synthesis. MIAT overexpression in H9c2 cells significantly reduced the miR-150 expression. MIAT inhibition also partly restored the miR-150 levels under Ang II treatment. MiR-150 overexpression could attenuate the Ang II induced upregulation of hypertrophic marker genes and suppress the Ang II induced hypertrophic phenotypes of the cells., Conclusions: MIAT is significantly increased in Ang II induced cardiac hypertrophy and contributes to the pathological development. MIAT can suppress miR-150 expression in cardiomyocytes and miR-150 is a downstream effector of MIAT in the development of cardiac hypertrophy.

Objective: To investigate the effect of MiR-200b on human retinal endothelial cells (hRECs) cultured in high glucose and explore the mechanism., Methods: hRECs cultured in high glucose or in normal media were examined for MiR-200b mRNA expression using real-time PCR. The effect of MiR-200b transfection on hREC proliferation in high-glucose culture was evaluated with MTT assay, and real-time PCR and Western blotting were performed to determine vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGFβ1) expression in the transfected cells., Results: The cells in high-glucose culture showed significantly decreased MiR-200b expression and active proliferation. Compared with those in normal control cells, VEGF and TGFβ1 mRNA and protein expressions increased markedly in cells cultured in high glucose (P<0.05). MiR-200b transfection of the cells caused significantly increased cellular expression of MiR-200b but decreased expression levels of VEGF and TGFβ1 mRNA and protein, and suppressed hREC proliferation in high glucose culture (P<0.05)., Conclusion: MiR-200b can regulate REC growth and proliferation by changing VEGF and TGFβ1 expressions and thus play a role in the pathogenesis and progression of diabetic retinopathy.