MiR-451 suppresses proliferation, migration and promotes apoptosis of the human osteosarcoma by targeting macrophage migration inhibitory factor

Metformin Exhibits Anti-Inflammatory Effects by Regulating microRNA-451/CXCL16 and B Cell Leukemia/Lymphoma 2 in Patients With Osteoarthritis

OBJECTIVE

Osteoarthritis (OA) is the most common cause of chronic disability in joints among older individuals. The primary goal of OA treatment is pain relief to improve the quality of life. Inflammation and aging are involved in the pathogenesis of pain in OA. In this study, we evaluated the ability of metformin to regulate microRNAs, such as miR-451 and miR-15b, and their target proteins, CXCL16 and B cell leukemia/lymphoma 2 (BCL-2), involved in inflammation and apoptosis.

METHODS

In this double-blind placebo-controlled clinical trial, patients were randomly divided into two groups: one receiving metformin and the other receiving a placebo for four months (starting at 0.5 g/day for the first week, increasing to 1 g/day for the second week, and increasing to 1.5 g/day for the remaining period). In addition to evaluating the clinical response using the Knee Injury and Osteoarthritis Outcome Score questionnaire, miR-451 and miR-15b expression levels were detected using real-time polymerase chain reaction. The serum levels of CXCL16 and BCL-2 were evaluated using enzyme-linked immunosorbent assay kits before (time zero) and after treatment (month four).

RESULTS

Metformin increased miR-451 expression levels simultaneously with pain reduction, whereas miR-15b expression did not change significantly after four months of treatment. Also, metformin decreased the serum levels of BCL-2 and CXCL16 in patients with OA.

CONCLUSION

The effects of metformin in reducing pain can be attributed to many factors, including its anti-inflammatory and antiaging effects. Our findings suggest that metformin may reduce pain and inflammation in patients with OA through the regulation of miR-451/CXCL16 and BCL-2.

Regulation of immune cells by miR-451 and its potential as a biomarker in immune-related disorders: a mini review

In 2005, Altuvia and colleagues were the first to identify the gene that encodes miR-451 in the human pituitary gland, located in chromosome region 17q11.2. Subsequent studies have confirmed that miR-451 regulates various immune cells, including T cells, B cells, microglia, macrophages, and neutrophils, thereby influencing disease progression. The range of immune-related diseases affected encompasses various cancers, lymphoblastic leukemia, and injuries to the lungs and spinal cord, among others. Moreover, miR-451 is produced by immune cells and can regulate both their own functions and those of other immune cells, thus creating a regulatory feedback loop. This article aims to comprehensively review the interactions between miR-451 and immune cells, clarify the regulatory roles of miR-451 within the immune system, and assess its potential as both a therapeutic target and a biomarker for immune-related diseases.

The role of MIF in periodontitis: A potential pathogenic driver, biomarker, and therapeutic target

OBJECTIVE

Periodontitis is an inflammatory disease that involves an imbalance in the oral microbiota, activation of inflammatory and immune responses, and alveolar bone destruction. Macrophage migration inhibitory factor (MIF) is a versatile cytokine involved in several pathological reactions, including inflammatory processes and bone destruction, both of which are characteristics of periodontitis. While the roles of MIF in cancer and other immune diseases have been extensively characterized, its role in periodontitis remains inconclusive.

RESULTS

In this review, we describe a comprehensive analysis of the potential roles of MIF in periodontitis from the perspective of immune response and bone regulation at the cellular and molecular levels. Moreover, we discuss its potential reliability as a novel diagnostic and therapeutic target for periodontitis.

CONCLUSION

This review can aid dental researchers and clinicians in understanding the current state of MIF-related pathogenesis, diagnosis, and treatment of periodontitis.

The Landscape of microRNAs in Bone Tumor: A Comprehensive Review in Recent Studies

Cancer, the second greatest cause of mortality worldwide, frequently causes bone metastases in patients with advanced-stage carcinomas such as prostate, breast, and lung cancer. The existence of these metastases contributes to the occurrence of skeletal-related events (SREs), which are defined by excessive pain, pathological fractures, hypercalcemia, and spinal cord compression. These injurious incidents leave uncomfortably in each of the cancer patient's life quality. Primary bone cancers, including osteosarcoma (OS), chondrosarcoma (CS), and Ewing's sarcoma (ES), have unclear origins. MicroRNA (miRNA) expression patterns have been changed in primary bone cancers such as OS, CS, and ES, indicating a role in tumor development, invasion, metastasis, and treatment response. These miRNAs are persistent in circulation and exhibit distinct patterns in many forms of bone tumors, making them potential biomarkers for early detection and treatment of such diseases. Given their crucial regulatory functions in various biological processes and conditions, including cancer, this study aims to look at miRNAs' activities and possible contributions to bone malignancies, focusing on OS, CS, and ES. In conclusion, miRNAs are valuable tools for diagnosing, monitoring, and predicting OS, CS, and ES outcomes. Further research is required to fully comprehend the intricate involvement of miRNAs in these bone cancers and to develop effective miRNA-based treatments.

Enriched Environment Induces Sex-Specific Changes in the Adult Neurogenesis, Cytokine and miRNA Expression in Rat Hippocampus

An enriched environment stimulates adult hippocampal plasticity, but the exact cellular and molecular mechanisms are complex, and thus a matter of debate. We studied the behavior and hippocampal neurogenesis in adult male and female Wistar rats that were housed in an enriched environment (EE) for two months. Both EE males and females performed better than control animals in a Barnes maze, meaning that EE enhances spatial memory. However, the expression levels of neurogenesis markers KI67, DCX, Nestin, and Syn1 increased only in EE females, while in EE males only KI67 and BDNF were higher than in the corresponding control. The number of DCX+ neurons on brain slices increased in the dentate gyrus of EE females only, i.e., the level of adult hippocampal neurogenesis was increased in female but not in male rats. The level of anti-inflammatory IL-10 and signaling pathway components was upregulated in EE females. Of 84 miRNAs tested, in the hippocampi of EE female rats we detected upregulation in the expression levels of 12 miRNAs related to neuronal differentiation and morphogenesis, while in EE males four miRNAs were upregulated and involved in the regulation of cell proliferation/differentiation, and one was downregulated and associated with the stimulation of proliferation. Taken altogether, our results point to sex-specific differences in adult hippocampal plasticity, IL-10 expression, and miRNA profiles induced by an enriched environment.

Regulation of Molecular Targets in Osteosarcoma Treatment

The most prevalent malignant bone tumor, osteosarcoma, affects the growth plates of long bones in adolescents and young adults. Standard chemotherapeutic methods showed poor response rates in patients with recurrent and metastatic phases. Therefore, it is critical to develop novel and efficient targeted therapies to address relapse cases. In this regard, RNA interference technologies are encouraging options in cancer treatment, in which small interfering RNAs regulate the gene expression following RNA interference pathways. The determination of target tissue is as important as the selection of tissue-specific promoters. Moreover, small interfering RNAs should be delivered effectively into the cytoplasm. Lentiviral vectors could encapsulate and deliver the desired gene into the cell and integrate it into the genome, providing long-term regulation of targeted genes. Silencing overexpressed genes promote the tumor cells to lose invasiveness, prevents their proliferation, and triggers their apoptosis. The uniqueness of cancer cells among patients requires novel therapeutic methods that treat patients based on their unique mutations. Several studies showed the effectiveness of different approaches such as microRNA, drug- or chemotherapy-related methods in treating the disease; however, identifying various targets was challenging to understanding disease progression. In this regard, the patient-specific abnormal gene might be targeted using genomics and molecular advancements such as RNA interference approaches. Here, we review potential therapeutic targets for the RNA interference approach, which is applicable as a therapeutic option for osteosarcoma patients, and we point out how the small interfering RNA method becomes a promising approach for the unmet challenge.

Shexiang Baoxin Pill Regulates Intimal Hyperplasia, Migration, and Apoptosis after Platelet-Derived Growth Factor-BB-Stimulation of Vascular Smooth Muscle Cells via miR-451

OBJECTIVE

To investigate the regulatory roles of Shexiang Baoxin Pill (SXBXW) in neointimal formation and vascular smooth muscle cells (VSMCs) invasion and apoptosis as well as the potential molecular mechanisms using cultured VSMCs model of vascular injury (platelet-derived growth factor (PDGF)-BB-stimulated) in vitro.

METHODS

VSMCs were randomly assigned to 5 groups: blank, PDGF-BB (20 ng/mL+ 0.1% DMSO), SXBXW-L (PDGF-BB 20 ng/mL + SXBXW low dose 0.625 g/L), SXBXW-M (PDGF-BB 20 ng/mL + SXBXW medium dose 1.25 g/L) and SXBXW-H (PDGF-BB 20 ng/mL+ SXBXW high dose 2.5 g/L) group. Cell proliferation was assessed using cell counting kit-8 (CCK-8) assay and bromodeoxyuridine (BrdU) incorporation assay, the migration effects were detected by Transwell assay, cell apoptosis rate was measured by the Annexin V/propidium iodide (PI) apoptosis kit. The markers of contractile phenotype of VSMCs were detected with immunofluorescent staining. To validate the effects of miR-451 in regulating proliferation, migration and apoptosis treated with SXBXW, miR-451 overexpression experiments were performed, the VSMCs were exposed to PDGF-BB 20 ng/mL + 0.1% DMSO and later divided into 4 groups: mimic-NC (multiplicity of infection, MOI=50), SXBXW (1.25 g/L) + mimic-NC, mimic-miR451 (MOI=50), and SXBXW (1.25 g/L) + mimic-miR451, and alterations of proteins related to the miR-451 pathway were analyzed using Western blot.

RESULTS

PDGF-BB induced VSMCs injury causes acceleration of proliferation and migration. SXBXW inhibited phenotypic switching, proliferation and migration and promoted cell apoptosis in PDGF-BB-induced VSMCs. In addition, miR-451 was shown to be down-regulated in the VSMCs following PDGF-BB stimulation. SXBXW treatment enhanced the expression of miR-451 in PDGF-BB-induced VSMCs (P<0.05). Compared with SXBXW + mimic-NC and mimic-miR451 groups, the expression of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (Ywhaz) and p53 was further reduced in SXBXW + mimic-miR451 group, while activating transcription factor 2 (ATF2) was increased in VSMCs (P<0.05).

CONCLUSION

SXBXW regulated proliferation, migration and apoptosis via activation of miR-451 through ATF2, p53 and Ywhaz in PDGF-BB-stimulated VSMCs.

Molecular mechanism of microRNAs regulating apoptosis in osteosarcoma

Osteosarcoma is a primary malignant bone tumor with no effective treatment. Apoptosis, one of the programmed cell death, is any pathological form of cell death mediated by intracellular processes. Under the pathological state, the de-regulated regulation of apoptosis can disrupt the balance between cell proliferation and death, causing osteosarcoma proliferation and metastasis. As carcinogenic or tumor suppressor factors, microRNAs (miRNAs) regulate apoptosis of osteosarcoma cells by regulating apoptosis-related genes and apoptosis-related signaling pathways, such as mitochondrial apoptosis pathway, death receptor pathway, and endoplasmic reticulum pathway. Meanwhile as these abnormal miRNAs can be stored and transported by exosomes, detecting exosomes can be seen an effective method to diagnose osteosarcoma in the early stage. This review provides the current knowledge of miRNAs and their target genes related to the apoptosis of osteosarcoma, summarizes abnormal expression and regulation of miRNAs and signaling pathways in osteosarcoma and prospects the detection of exosome as a method for early diagnosis of osteosarcoma.

Influence of Trichomonas vaginalis macrophage migration inhibitory factor on the proliferation activity of prostate epithelial cell line and its preliminary mechanism

Currently, the pathogenesis of prostate diseases is still under investigation, but it is generally clinically recognized to be related to the imbalance of prostate cell viability. Trichomonas vaginalis macrophage migration inhibitory factor (TvMIF) has been reported to induce the proliferation and invasion of prostate cancer cells, but for normal PECs, the relationship between them has not been reliably confirmed. Therefore, this research aims to determine the influence of macrophage TvMIF on prostate epithelial cells (PECs) and its preliminary mechanism. The activity of RWPE-1 human normal prostate epithelial cells, the inflammatory response state, the expression of miR-451, and the effect of miR-451 on RWPE-1 were detected after TvMIF intervention. We found that TvMIF can enhance RWPE-1 cell proliferation and activate inflammatory factors by suppressing miR-451, thus taking part in the development and proliferation of diseases such as prostatic hyperplasia and prostatitis.

An Overview on the Role of miR-451 in Lung Cancer: Diagnosis, Therapy, and Prognosis

MicroRNAs (miRNAs) are highly conserved non-coding RNAs involved in many physiological processes such as cell proliferation, inhibition, development of apoptosis, differentiation, suppresses tumorigenicity, and regulating cell growth. The description of the alterations of miRNA expression patterns in cancers will be helpful to recognize biomarkers for early detection and possible therapeutic intervention in the treatment of cancers. Recent studies have shown that miR-451 is broadly dysregulated in lung cancer and is a crucial agent in lung tumor progression. This review summarizes recent advances of the potential role of miR-451 in lung cancer diagnosis, prognosis, and treatment and provides an insight into the potential use of miR-451 for the development of advanced therapeutic methods in lung cancer.

microRNA-451 (miR-451) Regulates the Apoptosis of Non-Small Cell Lung Cancer Cells by Targeting Macrophage Migration Promoting Factors

MicroRNA (miRNA) participates in cellular activities. This article mainly discusses whether miR-451 has a role in the apoptosis of non-small cell lung cancer (NSCLC) cells. A549 cell was divided into blank group, miR-451 overexpression group and NC group followed by analysis of level of miR-451, MIF mRNA, MIF, NF-κB, and nuclear expression of NF-κB by immunofluorescence, clone formation, cell apoptosis rate and cell cycle. miR-451 overexpression significantly inhibited MIF and NF-κB expression. In the case of miR-451 overexpression, NSCLC clone formation was inhibited time-dependently The nuclear NF-κB expression in miR451 group was significantly inhibited, indicating inhibition of MIF by miR-451, leading to inhibition of NSCLC cell proliferation. Further results showed that cell apoptotic rate of miR-451 high expression group was elevated with increased cell number in G2 phase, confirming that miR-451 overexpression promoted NSCLC cell apoptosis. miR-451 over-expression can inhibit MIF level by inhibiting NF-κB signaling pathway, thereby promoting NSCLC cell apoptosis, providing a new therapeutic approach for the clinical targeted therapy.

Extracellular vesicle-shuttled miRNAs as a diagnostic and prognostic biomarker and their potential roles in gallbladder cancer patients

Circulating microRNAs (miRNAs) in serum extracellular vesicles (EVs) are a promising biomarker in cancer. We aimed to elucidate the serum EVs miRNA biomarkers to identify patients with gallbladder cancer (GBC) and to clarify their potential roles. One hundred nineteen serum EVs from GBC and non-GBC individuals were isolated by pure-EVs-yieldable size-exclusion chromatography, and then were analyzed using a comprehensive miRNAs array and RT-qPCR-based validation. The functional roles of the identified miRNAs were also investigated using GBC cell lines. Serum EVs miR-1246 and miR-451a were significantly upregulated and downregulated, respectively in GBC patients (P = 0.005 and P = 0.001), in line with their expression levels in cancer tissue according to an in silico analysis. The combination of CEA and CA19-9 with miR-1246 showed the highest diagnostic power (AUC, 0.816; Sensitivity, 72.0%; Specificity, 90.8%), and miR-1246 was an independent prognostic marker of GBC (Hazard ratio, 3.05; P = 0.017) according to a Cox proportional hazards model. In vitro, miR-1246 promoted cell proliferation and invasion, while miR-451a inhibited cell proliferation and induced apoptosis with the targeting of MIF, PSMB8 and CDKN2D. Taken together, miR-1246 in serum EVs has potential application as a diagnostic and prognostic marker and miR-451a may be a novel therapeutic target in GBC.

Biological relevance and therapeutic potential of G-quadruplex structures in the human noncoding transcriptome

Noncoding RNAs are functional transcripts that are not translated into proteins. They represent the largest portion of the human transcriptome and have been shown to regulate gene expression networks in both physiological and pathological cell conditions. Research in this field has made remarkable progress in the comprehension of how aberrations in noncoding RNA drive relevant disease-associated phenotypes; however, the biological role and mechanism of action of several noncoding RNAs still need full understanding. Besides fulfilling its function through sequence-based mechanisms, RNA can form complex secondary and tertiary structures which allow non-canonical interactions with proteins and/or other nucleic acids. In this context, the presence of G-quadruplexes in microRNAs and long noncoding RNAs is increasingly being reported. This evidence suggests a role for RNA G-quadruplexes in controlling microRNA biogenesis and mediating noncoding RNA interaction with biological partners, thus ultimately regulating gene expression. Here, we review the state of the art of G-quadruplexes in the noncoding transcriptome, with their structural and functional characterization. In light of the existence and further possible development of G-quadruplex binders that modulate G-quadruplex conformation and protein interactions, we also discuss the therapeutic potential of G-quadruplexes as targets to interfere with disease-associated noncoding RNAs.

Micro-RNA-451 Reduces Proliferation of B-CPAP Human Papillary Thyroid Cancer Cells by Downregulating Expression of Activating Transcription Factor 2

Background

MicroRNAs (miRNAs) are novel biomarkers that are important in tumorigenesis and cancer treatment resistance. miR-451 is expressed in human papillary thyroid carcinoma (PTC) tissues and is associated with tumor progression. This study investigated the molecular mechanism associated with the effects of miR-451 on B-CPAP human PTC cells in vitro.

Material/Methods

Binding of miRNAs to the 3′ untranslated region (3′UTR) of messenger RNA (mRNA) was determined with a luciferase reporter assay. miRNAs and plasmids were transfected into human PTC B-CPAP cells with Lipofectamine 2000 Transfection Reagent. Cell viability was tested with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. The levels of miRNAs and mRNA were determined with quantitative polymerase chain reaction and protein levels were analyzed with immunoblotting.

Results

miR-451 bound to wild-type but not mutant 3′-UTR of activating transcription factor 2 (ATF2). MiR-451 mimics inhibited the growth of B-CPAP cells and reduced mRNA and protein levels in ATF2, whereas miR-451 inhibitors promoted the growth of B-CPAP cells and increased mRNA and protein levels in ATF2.

Conclusions

miR-451 directly bound to the 3′UTR of ATF2, decreased mRNA and protein levels in ATF2, and inhibited growth of B-CPAP cells. Our findings suggest that miR-451 may be a potential therapeutic target for PTC.

Human umbilical cord mesenchymal stem cells-derived exosomal microRNA-451a represses epithelial-mesenchymal transition of hepatocellular carcinoma cells by inhibiting ADAM10

Exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs) expressing microRNAs (miRNAs) have been highlighted in human cancers. However, the detailed molecular mechanism of hucMSCs-derived exosomal miR-451a on hepatocellular carcinoma (HCC) remains further investigation. Our study aims to explore the impact of exosomal miR-451a on the progression of HCC. Expression of miR-451a and a disintegrin and metalloprotease 10 (ADAM10) in HCC tissues and adjacent normal tissues were determined. The exosomes were extracted from hucMSCs and co-cultured with Hep3B and SMMC-7721 cell lines. After the treatment of relative exosomes or exosome inhibitor GW4869 in Hep3B and SMMC-7721 cells, the paclitaxel resistance and malignant phenotypes of HCC cells were measured. Moreover, the effect of hucMSCs-derived exosomes on the expression of miR-451a and ADAM10 in HCC cells was assessed. The targeting relationship between miR-451a and ADAM10 was verified to detect the impact of ADAM10-wild type and ADAM10-mutant type (MUT) on HCC cell processes. Low expression of miR-451a and high expression of ADAM10 indicated a poor prognosis of HCC patients. MiR-451a was up-regulated while ADAM10 was down-regulated in HCC cells after co-culture with HucMSC-derived exosomes. The exosomes elevated miR-451a and inhibited ADAM10 to suppress the paclitaxel resistance, cell cycle transition, proliferation, migration and invasion, and promote apoptosis of HCC cells. ADAM10 was verified to be a target gene of miR-451a. ADAM10-MUT promoted HCC process independent of miR-451a mimic. HucMSC-derived exosomal miR-451a could restrict the epithelial-mesenchymal transition of HCC cells by targeting ADAM10, which might provide new targets for HCC treatment.

Role of microRNAs in the crosstalk between osteosarcoma cells and the tumour microenvironment

Osteosarcoma (OS) is the most common primary bone tumour, with a peak incidence in adolescents, and the five-year survival rate of patients with metastasis or recurrence is much lower than that of patients without metastasis and recurrence. OS is initiated and develops in a complex tumour microenvironment (TME) that contains many different components, such as osteoblasts, osteoclasts, mesenchymal stem cells, fibroblasts, immune cells, extracellular matrix (ECM), extracellular vesicles, and cytokines. The extensive interaction between OS and the TME underlies OS progression. Therefore, rather than targeting OS cells, targeting the key factors in the TME may yield novel therapeutic approaches. MicroRNAs (miRNAs) play multiple roles in the biological behaviours of OS, and recent studies have implied that miRNAs are involved in mediating the communication between OS cells and the surrounding TME. Here, we review the TME landscape and the miRNA dysregulation of OS, describe the role of the altered TME in OS development and highlight the role of miRNA in the crosstalk between OS cells and the TME.

COLEC12 regulates apoptosis of osteosarcoma through Toll-like receptor 4-activated inflammation

OBJECTIVE

To investigate the role of COLEC12 in osteosarcoma and observe the relationship between COLEC12 knockdown and the inflammation of osteosarcoma. Then, further explore whether the process is regulated by TLR4.

METHOD

GEPIA and TCGA systems were used to predict the potential function of COLEC12. Western blot and RT-PCR were used to analyze the protein expression, or mRNA level, of COLEC12 in different tissue or cell lines. The occurrence and development of osteosarcoma were observed by using COLEC12 knockdown lentivirus. The inflammation indexes of osteosarcoma, in vitro and in vivo, were explored. TLR4 knockdown lentivirus was applied to the relationship between COLEC12 and TLR4.

RESULTS

COLEC12 expression in SARC tumor tissue was higher than in normal, and a high expression of COLEC12 in SARC patients had a worse prognostic outcome. Pairwise gene correlation analysis revealed a potential relationship between COLEC12 and TLR4. The COLEC12 expression and mRNA level in the tumor or Saos-2 cells were increased. COLEC12 knockdown lentivirus could inhibit osteosarcoma development, in vivo and vitro, through reducing tumor volume and weight, weakening tumor proliferation, migration, and invasion, and enhancing apoptosis. Furthermore, COLEC12 knockdown could increase inflammation of osteosarcoma, in vivo and in vitro, through inducing myeloperoxidase (MPO), TLR4, NF-κB, and C3, and expression of related inflammatory factors. Finally, TLR4 knockdown lentivirus inhibits the progress of inflammation after COLEC12 regulation, in vivo and vitro.

CONCLUSION

COLEC12 may be able to regulate apoptosis and inflammation of osteosarcoma, and TLR4 may be the downstream target factor of COLEC12 in inflammation.

ssc-miR-451 Regulates Porcine Primary Adipocyte Differentiation by Targeting ACACA

miRNA is a small non-coding RNA, which plays an important role in diverse biological processes. In the present study, we explore the effect of ssc-miR-451 on porcine adipose development and meat quality. We observed that ssc-miR-451 was downregulated during porcine primary adipocyte differentiation. Overexpression of ssc-miR-451 inhibited adipogenic differentiation, while inhibition of ssc-miR-451 promoted adipogenic differentiation. The dual luciferase reporter system indicated Acetyl-CoA carboxylase alpha (ACACA) as a target gene of ssc-miR-451. Correlation analysis negatively correlated miR-451 expression with intramuscular fat content (IMF) and positively correlated ACACA expression with IMF. Further analysis of fatty acid composition revealed that pigs with high expression of ssc-miR-451 had higher monounsaturated fatty acid (MUFA) and lower polyunsaturated fatty acid (PUFA). Taken together, our study suggests that ssc-miR-451 regulates lipid deposition and fatty acid composition by targeting ACACA, and ssc-miR-451 may serve as a potential genetic marker to improve pork quality.

The role of significantly deregulated MicroRNAs in osteosarcoma based on bioinformatic analysis

OBJECTIVE

This study aimed to identify potential key microRNAs (miRNAs) in osteosarcoma and construct miRNA-mRNA negative regulatory networks through analysis of the Gene Expression Omnibus (GEO) database.

METHODS

The differentially expressed miRNAs (DE-miRNAs) in GSE28423 were screened, and their prognostic value was assessed with the prognostic data of GSE39058. The target genes of prognostic DE-miRNAs were predicted and underwent Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. In addition, the expression of all predicted target genes were assessed using the mRNA array data of GSE28424. Finally, the gene-drug interaction network was constructed.

RESULTS

We identified 205 DE-miRNAs between osteosarcoma cells and normal bone. Among them, high expression of miR-411-3p and miR-487b-5p were correlated with prolonged survival. Furthermore, 2659 genes predicted as targets of miR-411-3p or miR-487b-5p were clustered in 42 significant GO categories, including "regulation of neurotransmitter secretion" and "phosphoprotein binding", as well as 23 significant KEGG pathways, such as "MAPK signaling pathway" and "Ras signaling pathway". Five of the 75 overlapping target genes of miR-411-3p and miR-487b-5p were downregulated in osteosarcoma, including ZBTB20, ADAMTS4, GLIPR2, CLIC5 and CBX7.

CONCLUSIONS

Our findings might help clarify molecular mechanisms underlying the oncogenesis and development, and offer potential targets for osteosarcoma.

Inhibition of microRNA-451 is associated with increased expression of Macrophage Migration Inhibitory Factor and mitgation of the cardio-pulmonary phenotype in a murine model of Bronchopulmonary Dysplasia

Background

Macrophage migration inhibitory factor (MIF) has been implicated as a protective factor in the development of bronchopulmonary dysplasia (BPD) and is known to be regulated by MicroRNA-451 (miR-451). The aim of this study was to evaluate the role of miR-451 and the MIF signaling pathway in in vitro and in vivo models of BPD.

Methods

Studies were conducted in mouse lung endothelial cells (MLECs) exposed to hyperoxia and in a newborn mouse model of hyperoxia-induced BPD. Lung and cardiac morphometry as well as vascular markers were evaluated.

Results

Increased expression of miR-451 was noted in MLECs exposed to hyperoxia and in lungs of BPD mice. Administration of a miR-451 inhibitor to MLECs exposed to hyperoxia was associated with increased expression of MIF and decreased expression of angiopoietin (Ang) 2. Treatment with the miR-451 inhibitor was associated with improved lung morphometry indices, significant reduction in right ventricular hypertrophy, decreased mean arterial wall thickness and improvement in vascular density in BPD mice. Western blot analysis demonstrated preservation of MIF expression in BPD animals treated with a miR-451 inhibitor and increased expression of vascular endothelial growth factor-A (VEGF-A), Ang1, Ang2 and the Ang receptor, Tie2.

Conclusion

We demonstrated that inhibition of miR-451 is associated with mitigation of the cardio-pulmonary phenotype, preservation of MIF expression and increased expression of several vascular growth factors.

Phase I study of imalumab (BAX69), a fully human recombinant antioxidized macrophage migration inhibitory factor antibody in advanced solid tumours

Aim

Preclinical evidence suggests that oxidized macrophage migration inhibitory factor (oxMIF) may be involved in carcinogenesis. This phase 1 study (NCT01765790) assessed the safety, tolerability, pharmacokinetics and antitumour activity of imalumab, an oxMIF inhibitor, in patients with advanced cancer using ‘3 + 3’ dose escalation.

Methods

In Schedule 1, patients with solid tumours received doses from 1 to 50 mg/kg IV every 2 weeks. In Schedule 2, patients with metastatic colorectal adenocarcinoma, non‐small‐cell lung, or ovarian cancer received weekly doses of 10 or 25 mg/kg IV (1 cycle = 28 days). Treatment continued until disease progression, unacceptable toxicity, dose‐limiting toxicity, or withdrawal of consent.

Results

Fifty of 68 enrolled patients received imalumab. The most common treatment‐related adverse events (TRAEs) included fatigue (10%) and vomiting (6%); four grade 3 serious TRAEs (two patients) occurred. The dose‐limiting toxicity was allergic alveolitis (one patient, 50 mg/kg every 2 weeks). The maximum tolerated and biologically active doses were 37.5 mg/kg every 2 weeks and 10 mg/kg weekly, respectively. Of 39 assessed patients, 13 had stable disease (≥4 months in 8 patients).

Conclusions

Imalumab had a maximum tolerated dose of 37.5 mg/kg every 2 weeks in patients with advanced solid tumours, with a biologically active dose of 10 mg/kg weekly. Further investigation will help define the role of oxMIF as a cancer treatment target.

lncRNA FLVCR-AS1 promotes osteosarcoma growth by targeting miR381-3p/CCND1

Purpose

This article reports on FLVCR-AS1 effects on osteosarcoma (OS) growth.

Methods

Tumor tissue and adjacent normal tissue of 48 OS patients were collected. HOS and 143B cells were transfected. Gene expression was examined with qRT-PCR and Western blot. CCK8 assays and cell cloning was performed to measure cell proliferation. Cell cycle and apoptosis were assessed. Luciferase-reporter gene assays and RNA pull-down tests were used to detect targeting relationships between genes.

Results

Prominently higher FLVCR-AS1 expression was found in OS tissue and cells, and was associated with poor prognosis (P<0.05, P<0.01, or P<0.001). Compared with the siCtrl group, 143B and HOS cells of the siFLVCR-AS1 group had significantly lower OD₄₅₀ values and clone numbers and obviously higher percentages of cells in the G₁ phase and apoptosis (P<0.01 or P<0.001). miR381-3p expression was directly inhibited by FLVCR-AS1, and CCND1 expression was directly suppressed by miR381-3p. Compared with the FLVCR-AS1 group, 143B cells of the FLVCR-AS1⁺ miR381-3p mimic group and FLVCR-AS1⁺ siCCND1 group showed remarkably lower OD₄₅₀ values and clone numbers obviously higher apoptosis and percentage of cells in the G₁ phase (P<0.05, P<0.01, or P<0.001).

Conclusion

FLVCR-AS1 promoted OS growth by upregulating CCND1 expression via downregulation of miR381-3p.

miR-451: A Novel Biomarker and Potential Therapeutic Target for Cancer

MicroRNAs (miRNAs) are endogenous, non-coding, single-stranded small RNAs involved in a variety of cellular processes, including ontogeny, cell proliferation, differentiation, and apoptosis. They can also function as oncogenes or tumor suppressor genes. Recent studies have revealed that miRNA-451 (miR-451) is involved in the regulation of various human physiological and pathological processes. Furthermore, it has been shown that miR-451 not only directly affects the biological functions of tumor cells but also indirectly affects tumor cell invasion and metastasis upon secretion into the tumor microenvironment via exosomes. Thus, miR-451 also influences the progression of tumorigenesis and drug resistance. This review summarizes the expression of miR-451 in various cancer types and the relationship between miR-451 and the diagnosis, treatment, and drug resistance of solid tumors. In addition, we address possible mechanisms of action of miR-451 and its potential application as a biomarker in the diagnosis and treatment of human cancers.

miRNA signatures in childhood sarcomas and their clinical implications

Progresses in multimodal treatments have significantly improved the outcomes for childhood cancer. Nonetheless, for about one-third of patients with Ewing sarcoma, rhabdomyosarcoma, or osteosarcoma steady remission has remained intangible. Thus, new biomarkers to improve early diagnosis and the development of precision-targeted medicine remain imperative. Over the last decade, remarkable progress has been made in the basic understanding of miRNAs function and in interpreting the contribution of their dysregulation to cancer development and progression. On this basis, this review focuses on what has been learned about the pivotal roles of miRNAs in the regulation of key genes implicated in childhood sarcomas.

Upregulation of miR‑95-3p inhibits growth of osteosarcoma by targeting HDGF

Osteosarcoma is the most common bone malignancy and miR-95-3p plays an important role in multiple cancers. The purpose of this study was to explore the effect and potential mechanism of miR-95-3p on the growth of osteosarcoma. In vitro, the osteosarcoma cell lines, SAOS-2 and U2OS cells, were transfected with miR-95-agomir to assess the role of miR-95-3p in proliferation and apoptosis of osteosarcoma cells. We determined that overexpression of miR-95-3p significantly attenuated cell proliferation but enhanced apoptosis in SAOS-2 and U2OS cells. We also found that overexpression of miR-95-3p in osteosarcoma cells downregulated the expression of hepatoma-derived growth factor (HDGF). Next, knockdown of HDGF by siRNA targeting HDGF clearly inhibited cell proliferation and induced apoptosis in U2OS cells. In vivo, a tumor formation assay in BALB/c nude mice was conducted by injecting the pre-miR-95 or control vector lentivirus-infected U2OS cells to determine the effect of miR-95-3p on the growth of osteosarcoma. Results showed miR-95-3p overexpression inhibited the osteosarcoma growth and downregulated the HDGF expression in xenografted tumor. For mechanism study, we co-transfected HDGF/pcDNA3.1 plasmid and miR-95-agomir to U2OS cells, and we demonstrated that overexpression of HDGF could attenuate the effects of miR-95-3p on U2OS cell proliferation, apoptosis and migration. These findings indicated that miR-95-3p might act as a potential tumor suppressor in osteosarcoma by targeting HDGF. Thus, miR-95-3p may become a potential therapeutic in treatment of osteosarcoma.

Downregulation of microRNA‑451 improves cell migration, invasion and tube formation in hypoxia‑treated HUVECs by targeting MIF

Angiogenesis is a critical process of recovery from cerebrovascular disease. A growing body of evidence has confirmed that microRNAs (miRNAs/miRs) have an important role in the modulation of angiogenesis under physiological and pathological conditions including cerebral ischemia injury (CII). Therefore, the aim of the present study was to explore the function and mechanism of microRNAs in regulating angiogenesis using a cell model of CII. Firstly, a miRNA microarray was performed to analyze miRNA expression in serum samples from patients with cerebral ischemia and the results revealed that miR-451 was one of the miRNAs that was the most significantly downregulated. Subsequently, human umbilical vein endothelial cells (HUVECs) were used as an in vitro model to further explore the mechanisms governing angiogenesis during hypoxia. The results demonstrated that overexpression of miR-451 had a significantly anti-angiogenic effect by suppressing tube formation, migration and wound healing in vitro. By contrast, reducing the expression of miR-451 promoted HUVEC migration and tubulogenesis under normoxic conditions. The present study further identified that macrophage migration inhibitory factor (MIF), an important angiogenic regulator, was a novel target of miR-451 that could reverse the effects of miR-451 on the regulation of angiogenesis in HUVECs under hypoxic or normoxic conditions. These results revealed that downregulation of miR-451 promotes angiogenesis by targeting MIF in hypoxic HUVECs and indicated that miR-451 is a potential candidate for CII therapeutics.

A comprehensive review on miR-451: A promising cancer biomarker with therapeutic potential

MicroRNAs (miRNAs) are proposed as a family of short noncoding molecules able to manage and control the expression of the gene targets at the posttranscriptional level. They contribute in several fundamental physiological mechanisms as well as a verity of human and animal diseases such as cancer progression. Among these tiny RNAs, miR-451 placed on chromosome 17 at 17q11.2 presents an essential role in many biological processes in health condition and also in pathogenesis of different diseases. Besides, it has been recently considered as a valuable biomarker for cancer detection, prognosis and treatment. Therefore, this review will provide the critical functions of miR-451 on biological mechanisms including cell cycle and proliferation, cell survival and apoptosis, differentiation and development as well as disease initiation and progression such as tumor formation, migration, invasion, and metastasis.

Regulation of extracellular matrix vesicles via rapid responses to steroid hormones during endochondral bone formation

Endochondral bone formation is a precise and highly ordered process whose exact regulatory framework is still being elucidated. Multiple regulatory pathways are known to be involved. In some cases, regulation impacts gene expression, resulting in changes in chondrocyte phenotypic expression and extracellular matrix synthesis. Rapid regulatory mechanisms are also involved, resulting in release of enzymes, factors and micro RNAs stored in extracellular matrisomes called matrix vesicles. Vitamin D metabolites modulate endochondral development via both genomic and rapid membrane-associated signaling pathways. 1α,25-dihydroxyvitamin D3 [1α,25(OH)₂D₃] acts through the vitamin D receptor (VDR) and a membrane associated receptor, protein disulfide isomerase A3 (PDIA3). 24R,25-dihydroxyvitamin D3 [24R,25(OH)₂D₃] affects primarily chondrocytes in the resting zone (RC) of the growth plate, whereas 1α,25(OH)₂D₃ affects cells in the prehypertrophic and upper hypertrophic cell zones (GC). This includes genomically directing the cells to produce matrix vesicles with zone specific characteristics. In addition, vitamin D metabolites produced by the cells interact directly with the matrix vesicle membrane via rapid signal transduction pathways, modulating their activity in the matrix. The matrix vesicle payload is able to rapidly impact the extracellular matrix via matrix processing enzymes as well as providing a feedback mechanism to the cells themselves via the contained micro RNAs.

Glucose dependent miR-451a expression contributes to parathyroid hormone mediated osteoblast differentiation

Parathyroid hormone (PTH; amino acid 1-34, known as teriparatide) has reported promoting differentiation and glucose uptake in osteoblasts. However, how PTH regulates glucose metabolism to facilitate osteoblast differentiation is not understood. Here, we report that PTH promotes glucose dependent miR-451a expression which stimulates osteoblast differentiation. In addition to glucose uptake, PTH suppresses AMPK phosphorylation via PI3K-mTOR-AKT axis thereby preventing phosphorylation and inactivation of octamer-binding transcription factor 1 (OCT-1) which has been reported to act on the promoter region of miR-451a. Modulation of AMPK activity controls miR-451a levels in differentiating osteoblasts. Moreover, pharmacological inhibition of PI3K-mTOR-AKT axis suppressed miR-451a via increased AMPK activity. We report that this glucose regulated miRNA is an anabolic target and transfection of miR-451a mimic induces osteoblast differentiation and mineralization in vitro. These actions were mediated through the suppression of Odd-skipped related 1 (Osr1) and activation of Runx2 transcription. When injected in vivo, the miR-451a mimic significantly increased osteoblastogenesis, mineralization, reversed ovariectomy induced bone loss and improved bone strength. Together, these findings suggest that enhanced osteoblast differentiation associated with bone formation in case of PTH therapy is also a consequence of elevated miR-451a levels via glucose regulation. Consequently, this miRNA has the potential to be a therapeutic target for conditions of bone loss.

MiR-451a attenuates free fatty acids-mediated hepatocyte steatosis by targeting the thyroid hormone responsive spot 14 gene

The thyroid hormone responsive spot 14 (THRSP) gene is a de novo lipogenesis-related gene that plays a significant role in the initiation and development of nonalcoholic fatty liver disease (NAFLD). Several previous studies had shown that endogenous and environmental factors could regulate the expression of THRSP. The role of microRNAs (miRNAs), however, in controlling THRSP expression has not been investigated. In this study, we first constructed the hepatic steatosis cell model by using a mixture of free fatty acids (FFAs; oleate/palmitate, 2:1 ratio) to treat and demonstrate the promotive role of THRSP in lipid accumulation in hepatic cells. By analyzing the photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) database and performing a luciferase reporter assay, we confirmed that microRNA-451a specifically binds to mouse and human THRSP 3'UTR and inhibits its activity. Overexpression of miR-451a efficiently reduced THRSP mRNA and protein expression as well as triglyceride (TG) accumulation in cultured hepatic cells (AML12 and HepG2). Moreover, overexpression of miR-451a significantly decreases TG accumulation in the livers of mice injected with an miR-451a agomir. All these results demonstrated that miR-451a might participate in the FFA-induced hepatic steatosis by regulating the expression of the THRSP gene which represents a new potential target for NAFLD therapy.

Potential Role of miRNAs as Theranostic Biomarkers of Epilepsy

Epilepsy includes a group of disorders of the brain characterized by an enduring predisposition to generate epileptic seizures. Although familial epilepsy has a genetic component and heritability, the etiology of the majority of non-familial epilepsies has no known associated genetic mutations. In epilepsy, recent epigenetic profiles have highlighted a possible role of microRNAs in its pathophysiology. In particular, molecular profiling identifies a significant number of microRNAs (miRNAs) altered in epileptic hippocampus of both animal models and human tissues. In this review, analyzing molecular profiles of different animal models of epilepsy, we identified a group of 20 miRNAs commonly altered in different epilepsy-animal models. As emerging evidences highlighted the poor overlap between signatures of animal model tissues and human samples, we focused our analysis on miRNAs, circulating in human biofluids, with a principal role in epilepsy hallmarks, and we identified a group of 8 diagnostic circulating miRNAs. We discussed the functional role of these 8 miRNAs in the epilepsy hallmarks. A few of them have also been proposed as therapeutic molecules for epilepsy treatment, revealing a great potential for miRNAs as theranostic molecules in epilepsy.

Highly expressed placental miRNAs control key biological processes in human cancer cell lines

Despite being a healthy tissue, the constituent cells of the placenta, share similar characteristics with tumor cells, such as increased cell growth, migration, and invasion. However, while these processes are stochastic and uncontrolled in cancer cells, in placenta they are precisely controlled. Since miRNAs have been reported to regulate genes that control the molecular mechanisms necessary for the development of both human placenta and cancer, we addressed for miRNAs highly expressed in the placenta that could be involved in tumorigenesis. Here, we assessed the miRNA profile in placenta samples using microarray analysis. The results showed that miR-451 and miR-720, highly expressed placental miRNAs, presented very low or undetectable expression in cancer cell lines compared to the normal placenta and healthy tissues. Additionally, transfection of miR-451 or miR-720 mimics in choriocarcinoma cell line (JEG3) and colorectal adenocarcinoma cell line (HT-29) resulted in impaired cell proliferation, decreased cell migration and invasion and reduced ability of colony formation. These findings provide evidence that placenta may work as an alternative model to identify novel miRNAs involved in pathways controlling tumorigenesis.

Long Noncoding RNA LINC01133 Functions as an miR-422a Sponge to Aggravate the Tumorigenesis of Human Osteosarcoma

Long noncoding RNAs (lncRNAs) have been verified to participate in various types of malignant tumors, including osteosarcoma (OS), which is the most common primary bone tumor with outstanding morbidity. Although an increasing number of lncRNAs have been reported to mediate the occurrence of OS, the potential mechanisms are still unclear. This study intends to uncover the mechanism by which lncRNA LINC01133 functions as an miRNA sponge to mediate OS tumorigenicity. In this study, we found that the expression level of LINC01133 was statistically upregulated in OS tumor tissue and cell lines compared to noncancerous tissues and a normal human osteoplastic cell line. LINC01133 silencing could also observably suppress the proliferation, migration, and invasion of OS cells (HOS and U2-OS). Bioinformatics analysis predicted that LINC01133 specifically targeted miR-422a, which was validated by dual-luciferase reporter assay. Furthermore, functional experiments revealed that miR-422a played a tumor-suppressive role in OS progression and could effectively reverse the function of LINC01133. In summary, our study discovered that lncRNA LINC01133 aggravates the proliferation, migration, and invasion of OS by sponging miR-422a, which provides a novel insight in the tumorigenesis of OS.

G-Quadruplexes influence pri-microRNA processing

RNA G-Quadruplexes (G4) have been shown to possess many biological functions, including the regulation of microRNA (miRNA) biogenesis and function. However, their impact on pri-miRNA processing remains unknown. We identified G4 located near the Drosha cleavage site in three distinct pri-miRNAs: pri-mir200c, pri-mir451a, and pri-mir497. The folding of the potential G4 motifs was determined in solution. Subsequently, mutations disrupting G4 folding led to important changes in the mature miRNAs levels in cells. Moreover, using small antisense oligonucleotides binding to the pri-miRNA, it was possible to modulate, either positively or negatively, the mature miRNA levels. Together, these data demonstrate that G4 motifs could contribute to the regulation of pri-mRNA processing, a novel role for G4. Considering that bio-informatics screening indicates that between 9% and 50% of all pri-miRNAs contain a putative G4, these structures possess interesting potential as future therapeutic targets.

The low expression of miR-451 predicts a worse prognosis in non-small cell lung cancer cases

PURPOSE

miR-451 is a tumor suppressive microRNA with several target genes, including Macrophage migration inhibitory factor (MIF). As little is known about the expression and clinicopathological significance of mir-451 in NSCLC, we performed a clinicopathological study of 370 NSCLC cases to clarify them. Cell biological experiments were also performed on NSCLC cell lines to confirm the tumor-suppressive role of miR-451 and whether or not MIF is targeted by miR-451.

METHODS

We analyzed 370 NSCLC cases for the miR-451 expression by quantitative real-time polymerase chain reaction and the MIF expression by immunohistochemistry. Eighty-four background lung tissue samples were also evaluated for the miR-451 expression. The clinicopathological and genetic factors surveyed were the disease-free survival, smoking status, histological type, disease stage, EGFR gene mutations and ALK rearrangements. In 286 adenocarcinoma cases, the invasive status (adenocarcinoma in situ, minimally invasive adenocarcinoma and invasive adenocarcinoma) was also evaluated. Five NSCLC cell lines (H23, H441, H522, H1703, and H1975) were cultured and evaluated for their miR-451 and MIF expression. The cell lines with lower miR-451 and higher MIF expressions were then selected and transfected with miR-451-mimic to observe its effects on MIF expression, Akt and Erk status, cell proliferation, and cell migration.

RESULTS

The miR-451 expression was down-regulated in cancer tissues compared with background lung tissues (P<0.0001). Factors such as advanced disease stage, positive pleural invasion and nodal status and being a smoker were significantly correlated with a lower expression of miR-451 (P<0.05 each), while EGFR gene mutations and ALK rearrangements were not. In adenocarcinoma, invasive and minimally invasive adenocarcinoma showed lower expression of miR-451 than adenocarcinoma in situ (P<0.0005, respectively). A survival analysis showed that a lower expression of miR-451 was an independent predictor of a poor prognosis for NSCLC (P<0.05). The MIF expression was inversely correlated with the miR-451 expression. Out of 5 NSCLC cell lines examined, H441 and H1975 showed higher MIF and lower miR-451 expressions. After the transfection of miR-451-mimic, the MIF expression and phosphorylated Akt expression of these cell lines was suppressed, as were cell proliferation and cell migration.

CONCLUSION

This clinicopathological study of 370 NSCLC cases and the cell biological studies of NSCLC cell lines clarified the tumor-suppressive role of miR-451 and its prognostic value. We also validated MIF as a target of miR-451 in NSCLC.