MicroRNA-210 promotes proliferation and invasion of peripheral nerve sheath tumor cells targeting EFNA3

The possible correlation between miR-762, Hippo signaling pathway, TWIST1, and SMAD3 in lung cancer and chronic inflammatory diseases

MicroRNAs are small RNA molecules that have a significant role in translational repression and gene silencing through binding to downstream target mRNAs. MiR-762 can stimulate the proliferation and metastasis of various types of cancer. Hippo pathway is one of the pathways that regulate tissue development and carcinogenesis. Dysregulation of this pathway plays a vital role in the progression of cancer. This study aimed to evaluate the possible correlation between miR-762, the Hippo signaling pathway, TWIST1, and SMAD3 in patients with lung cancer, as well as patients with chronic inflammatory diseases. The relative expression of miR-762, MST1, LATS2, YAP, TWIST1, and SMAD3 was determined in 50 lung cancer patients, 30 patients with chronic inflammatory diseases, and 20 healthy volunteers by real-time PCR. The levels of YAP protein and neuron-specific enolase were estimated by ELISA and electrochemiluminescence immunoassay, respectively. Compared to the control group, miR-762, YAP, TWIST1, and SMAD3 expression were significantly upregulated in lung cancer patients and chronic inflammatory patients, except SMAD3 was significantly downregulated in chronic inflammatory patients. MST1, LATS2, and YAP protein were significantly downregulated in all patients. MiR-762 has a significant negative correlation with MST1, LATS2, and YAP protein in lung cancer patients and with MST1 and LATS2 in chronic inflammatory patients. MiR-762 may be involved in the induction of malignant behaviors in lung cancer through suppression of the Hippo pathway. MiR-762, MST1, LATS2, YAP mRNA and protein, TWIST1, and SMAD3 may be effective diagnostic biomarkers in both lung cancer patients and chronic inflammatory patients. High YAP, TWIST1, SMA3 expression, and NSE level are associated with a favorable prognosis for lung cancer.

Exercise-Induced miR-210 Promotes Cardiomyocyte Proliferation and Survival and Mediates Exercise-Induced Cardiac Protection against Ischemia/Reperfusion Injury

Exercise can stimulate physiological cardiac growth and provide cardioprotection effect in ischemia/reperfusion (I/R) injury. MiR-210 is regulated in the adaptation process induced by exercise; however, its impact on exercise-induced physiological cardiac growth and its contribution to exercise-driven cardioprotection remain unclear. We investigated the role and mechanism of miR-210 in exercise-induced physiological cardiac growth and explored whether miR-210 contributes to exercise-induced protection in alleviating I/R injury. Here, we first observed that regular swimming exercise can markedly increase miR-210 levels in the heart and blood samples of rats and mice. Circulating miR-210 levels were also elevated after a programmed cardiac rehabilitation in patients that were diagnosed of coronary heart diseases. In 8-week swimming model in wild-type (WT) and miR-210 knockout (KO) rats, we demonstrated that miR-210 was not integral for exercise-induced cardiac hypertrophy but it did influence cardiomyocyte proliferative activity. In neonatal rat cardiomyocytes, miR-210 promoted cell proliferation and suppressed apoptosis while not altering cell size. Additionally, miR-210 promoted cardiomyocyte proliferation and survival in human embryonic stem cell-derived cardiomyocytes (hESC-CMs) and AC16 cell line, indicating its functional roles in human cardiomyocytes. We further identified miR-210 target genes, cyclin-dependent kinase 10 (CDK10) and ephrin-A3 (EFNA3), that regulate cardiomyocyte proliferation and apoptosis. Finally, miR-210 KO and WT rats were subjected to swimming exercise followed by I/R injury. We demonstrated that miR-210 crucially contributed to exercise-driven cardioprotection against I/R injury. In summary, this study elucidates the role of miR-210, an exercise-responsive miRNA, in promoting the proliferative activity of cardiomyocytes during physiological cardiac growth. Furthermore, miR-210 plays an essential role in mediating the protective effects of exercise against cardiac I/R injury. Our findings suggest exercise as a potent nonpharmaceutical intervention for inducing miR-210, which can alleviate I/R injury and promote cardioprotection.

microRNA-365 attenuated intervertebral disc degeneration through modulating nucleus pulposus cell apoptosis and extracellular matrix degradation by targeting EFNA3

This present study is aimed to investigate the role of microRNA-365 (miR-365) in the development of intervertebral disc degeneration (IDD). Nucleus pulposus (NP) cells were transfected by miR-365 mimic and miR-365 inhibitor, respectively. Concomitantly, the transfection efficiency and the expression level of miRNA were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Meanwhile, NP cells apoptosis was measured through propidium iodide (PI)-AnnexinV-fluorescein isothiocyanate (FITC) apoptosis detection kit. Subsequently, immunofluorescence (IF) staining was performed to assess the expression of collagen II, aggrecan and matrix metalloproteinase 13 (MMP-13). In addition, bioinformatic prediction and Luciferase reporter assay were used to reveal the target gene of miR-365. Finally, we isolated the primary NP cells from rats and injected NP-miR-365 in rat IDD models. The results showed that overexpression of miR-365 could effectively inhibit NP cells apoptosis and MMP-13 expression and upregulate the expression of collagen II and aggrecan. Conversely, suppression of miR-365 enhanced NP cell apoptosis and elevated MMP-13 expression, but decreased the expression of collagen II and aggrecan. Moreover, the further data demonstrated that miR-365 mediated NP cell degradation through targeting ephrin-A3 (EFNA3). In addition, the cells apoptosis and catabolic markers were increased in NP cells when EFNA3 upregulated. More importantly, the vivo data supported that miR-365-NP cells injection ameliorated IDD in rats models. miR-365 could alleviate the development of IDD by regulating NP cell apoptosis and ECM degradation, which is likely mediated by targeting EFNA3. Therefore, miR-365 may be a promising therapeutic avenue for treatment IDD through EFNA3.

Impact of Hypoxia-Induced miR-210 on Pancreatic Cancer

Pancreatic cancer (PC) poses significant clinical challenges, with late-stage diagnosis and limited therapeutic options contributing to its dismal prognosis. A hallmark feature of PC is the presence of a profoundly hypoxic tumour microenvironment, resulting from various factors such as fibrotic stroma, rapid tumour cell proliferation, and poor vascularization. Hypoxia plays a crucial role in promoting aggressive cancer behaviour, therapeutic resistance, and immunosuppression. Previous studies have explored the molecular mechanisms behind hypoxia-induced changes in PC, focusing on the role of hypoxia-inducible factors (HIFs). Among the myriad of molecules affected by hypoxia, microRNA-210 (miR-210) emerges as a central player. It is highly responsive to hypoxia and regulated by HIF-dependent and HIF-independent pathways. miR-210 influences critical cellular processes, including angiogenesis, metastasis, and apoptosis, all of which contribute to PC progression and resistance to treatment. Understanding these pathways provides insights into potential therapeutic targets. Furthermore, investigating the role of miR-210 and its regulation in hypoxia sheds light on the potential development of early diagnostic strategies, which are urgently needed to improve outcomes for PC patients. This review delves into the complexities of PC and introduces the roles of hypoxia and miR-210 in the progression of PC.

EphrinA3 is a key regulator of malignant behaviors and a potential prognostic factor in lung adenocarcinoma

BACKGROUND

As a member of the Ephrin protein family that elicits short distance cell-cell signaling, EphrinA3 has been shown to promote or inhibit tumorigenesis depending on tumor types, but its roles and the underlying mechanisms in lung adenocarcinoma (LUAD) have not been reported.

MATERIALS AND METHODS

The TCGA database and Kaplan-Meier Plotter database were used to analyze the differential expression of EphrinA3 between LUAD and para-carcinoma tissues, and its effect on overall survival of LUAD patients. CCK-8 assay, Edu assay, and flow cytometry were used to probe the effect of EphrinA3 on the proliferation of LUAD cells, and transwell assay was employed to examine its effect on migration and invasion. In addition, the effect of EphrinA3 on the growth of LUAD was further evaluated using a xenograft tumor model.

RESULTS

EphrinA3 was expressed highly in LUAD, and its expression level was negatively correlated with the prognosis of LUAD patients. In addition, EphrinA3 promoted proliferation, migration, and invasion of LUAD cells, and accelerated tumor growth in a xenograft LUAD model. The reported EphrinA3 receptors, EphA1 and EphA10, were expressed in clinical LUAD tissues and co-localized with EphrinA3 in LUAD cells. Mechanistically, EphrinA3/Eph signaling activated AKT, ERK, and p38MAPK, induced epithelial-mesenchymal transition (EMT), and upregulated matrix metalloproteases-2 and -9 (MMP-2/-9).

CONCLUSION

EphrinA3 expression was negatively correlated with prognosis of patients with LUAD. EphrinA3 promoted proliferation, migration, and invasion of LUAD cells. EphrinA3 enhanced the phosphorylation of ERK and AKT, and potentiates EMT and MMP expression in LUAD cells.

LncRNA LINC01270 aggravates the progression of gastric cancer through modulation of miR-326/EFNA3 axis

Gastric cancer (GC) is lethal malignancy, which is associated with high mortality. Long noncoding RNA LINC01270 has been identified to act as a potential oncogene in several cancers. However, its role and related regulatory mechanism in GC are yet to be illustrated. The levels of lncRNA LINC01270, miR-326, and EphrinA3 (EFNA3) were assessed by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Cell counting kit-8 (CCK-8) and colony formation assays were applied for analyzing cell proliferation. Transwell assay was used for measuring cellular migration and invasion. Western blot analysis was employed for evaluating the protein levels. Luciferase reporter and RNA pull-down assays were utilized to verify the binding ability between LINC01270 (or EFNA3) and miR-326. Our findings indicated that LINC01270 expression was significantly up-regulated in GC tissues and cell lines. Additionally, LINC01270 knockdown attenuated GC progression through inhibiting cell proliferation, migration, and invasion. Functional experiments identified that lncRNA LINC01270 could positively regulate EFNA3 expression by serving as a competing endogenous RNA (ceRNA) for miR-326. Through rescue assays, inhibition of GC progression caused by LINC01270 suppression was found to be reversed by the application of miR-326 inhibitor or EFNA3 overexpression. Overall, our work demonstrated that lncRNA LINC01270 can accelerate cell proliferation, migration, and invasion via modulating miR-326/EFNA3 axis. These findings might implicate the potential role of lncRNA LINC01270 in GC treatment.

How miRNAs Regulate Schwann Cells during Peripheral Nerve Regeneration-A Systemic Review

A growing body of studies indicate that small noncoding RNAs, especially microRNAs (miRNA), play a crucial role in response to peripheral nerve injuries. During Wallerian degeneration and regeneration processes, they orchestrate several pathways, in particular the MAPK, AKT, and EGR2 (KROX20) pathways. Certain miRNAs show specific expression profiles upon a nerve lesion correlating with the subsequent nerve regeneration stages such as dedifferentiation and with migration of Schwann cells, uptake of debris, neurite outgrowth and finally remyelination of regenerated axons. This review highlights (a) the specific expression profiles of miRNAs upon a nerve lesion and (b) how miRNAs regulate nerve regeneration by acting on distinct pathways and linked proteins. Shedding light on the role of miRNAs associated with peripheral nerve regeneration will help researchers to better understand the molecular mechanisms and deliver targets for precision medicine.

EFNA3 as a predictor of clinical prognosis and immune checkpoint therapy efficacy in patients with lung adenocarcinoma

BACKGROUND

Ephrin receptors (Eph) and their ligands, called ephrins, function in various disease processes. However, the expression level and prognostic value of Eph/ephrins in lung adenocarcinoma (LUAD) are still unclear.

METHODS

The Oncomine and GEPIA databases were used to explore the differential expression of Eph/ephrins in LUAD. Kaplan-Meier plotter was selected to explore the prognostic value of Eph/ephrins. The cBioPortal database was used to analyze the genetic variation of the EFNA3 gene. Immunohistochemistry was used to analyze the expression level and clinical value of ephrin-A3 protein in clinical LUAD tissue. Weighted coexpression network analysis (WGCNA) and gene set enrichment analysis (GSEA) identified the potential regulatory mechanism of EFNA3. CCK-8 assays and colony-forming experiments were used to investigate whether EFNA3 can regulate cell proliferation ability in LUAD. Analysis of lactate, ATP, and glucose uptake levels was used to explore the effect of EFNA3 on glycolysis ability. In addition, we investigated the relationship between EFNA3 and tumor infiltrating immune cells (TIICs). Finally, the potential immunotherapy response prediction value of EFNA3 was also explored.

RESULTS

In this study, we found that EFNA3 expression was significantly correlated with both overall survival (OS) and progression-free survival (PFS) in LUAD patients based on a comprehensive analysis of the Eph/Ephrin family. Next, the expression of the EFNA3 protein was increased in LUAD tissues and was designated an independent prognostic risk factor. Mechanistically, EFNA3 may be involved in nuclear division, synaptic function, and ion channel activity-related pathways. In vitro experiments confirmed the role of EFNA3 in promoting LUAD cells and showed that it could regulate glycolytic capacity. Moreover, EFNA3 was negatively associated with immunity, stromal infiltration, and several TIICs. Finally, EFNA3 was found to be positively related to multiple immunotherapy biomarkers.

CONCLUSIONS

In conclusion, increased EFNA3 in LUAD patients predicted worse clinical prognosis, promoted LUAD cell proliferation and glycolysis ability, and was related to immunotherapy response.

Prognostic and clinicopathological significance of miR-638 in cancer patients: A meta-analysis

INTRODUCTION

MiR-638 is believed to be involved in human cancers. However, the prognostic value of miR-638 in human carcinomas is controversial and inconclusive. Therefore, we conducted this meta-analysis to investigate the association between miR-638 expression and clinical outcomes in the patients with various cancers.

METHODS

We searched Pubmed, Embase, Wanfang, and the China National Knowledge Infrastructure (CNKI) up to September 1, 2020 to identify relevant studies. Hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were used to correlate expression of miR-638 with prognosis and clinicopathological features.

RESULTS

A total of 18 studies involving 1886 patients were included in the meta-analysis. The results revealed that low miR-638 expression was significantly correlated with poor overall survival (OS) (HR = 2.09, 95% CI: 1.46-2.98, P < .001), but not with disease-free survival (DFS) (HR = 1.71, 95% CI: 0.31-9.56, P = .540). Subgroup analysis found that low miR-638 expression was associated with worse OS in patients with digestive system cancer (HR = 2.47, 95% CI: 1.85-3.30, P < .001), the reported directly from articles group (HR = 2.12, 95% CI: 1.34-3.33, P < .001), survival curves group (HR = 2.02, 95% CI: 1.07-3.80, P = .029), in studies with sample size ≥100 (HR = 2.12, 95% CI: 1.34-3.35, P = .001), and in studies with sample size <100 (HR = 2.02, 95%CI: 1.09-3.75, P = .025). Moreover, cancer patients with low miR-638 expression were prone to tumor size (OR = 1.47, 95% CI: 1.03-2.09, P = .035), earlier lymph node metastasis (present vs absent, OR = 2.26, 95% CI: 1.63-3.14, P < .001), earlier distant metastasis (present vs absent, OR = 2.60, 95% CI: 1.45-4.67, P < .001), TNM stage (III-IV vs I-II, OR = 2.01, 95% CI: 1.35-2.99, P = .001), and portal vein invasion (present vs absent, OR = 4.39, 95% CI:2.23-8.64, P < .001), but not associated with age, gender, tumor differentiation, and vascular invasion.

CONCLUSIONS

MiR-638 may serve as a promising indicator in the prediction of prognosis and clinicopathological features in patients with different kinds of cancers.

Establishment and genomic characterization of a sporadic malignant peripheral nerve sheath tumor cell line

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive Schwann cell-derived neoplasms that occur sporadically or in patients with neurofibromatosis type 1 (NF1). Preclinical research on sporadic MPNSTs has been limited as few cell lines exist. We generated and characterized a new sporadic MPNST cell line, 2XSB, which shares the molecular and genomic features of the parent tumor. These cells have a highly complex karyotype with extensive chromothripsis. 2XSB cells show robust invasive 3-dimensional and clonogenic culture capability and form solid tumors when xenografted into immunodeficient mice. High-density single nucleotide polymorphism array and whole exome sequencing analyses indicate that, unlike NF1-associated MPNSTs, 2XSB cells have intact, functional NF1 alleles with no evidence of mutations in genes encoding components of Polycomb Repressor Complex 2. However, mutations in other genes implicated in MPNST pathogenesis were identified in 2XSB cells including homozygous deletion of CDKN2A and mutations in TP53 and PTEN. We also identified mutations in genes not previously associated with MPNSTs but associated with the pathogenesis of other human cancers. These include DNMT1, NUMA1, NTRK1, PDE11A, CSMD3, LRP5 and ACTL9. This sporadic MPNST-derived cell line provides a useful tool for investigating the biology and potential treatment regimens for sporadic MPNSTs.

circKMT2D contributes to H2O2-attenuated osteosarcoma progression via the miR-210/autophagy pathway

Circular RNAs (circRNAs) have been demonstrated to be involved in osteosarcoma (OS) development; however, the underlying mechanism of circKMT2D in OS progression remains unclear. The present study aimed to elucidate how circKMT2D could affect hydrogen peroxide (H₂O₂)-induced OS progression. H₂O₂ (100 µmol/l) was used to treat MG63 and U2OS cells. The cell viability, invasive ability, apoptosis and circKMT2D expression were detected using Cell Counting Kit-8 assay, Transwell assay, flow cytometry and reverse transcription-quantitative PCR, respectively. Furthermore, MG63 and U2OS cells transfected with circKMT2D short hairpin RNA and negative control were treated with H₂O₂, and circKMT2D expression and cell phenotype were determined. Dual-luciferase reporter assay was conducted to determine the association between circKMT2D and miR-210 expression level. Rescue experiments were conducted to examine the mechanisms through which circKMT2D and miR-210 could affect H₂O₂-treated MG63 cells. In addition, the effects of miR-210 on the expression of the autophagy-related proteins Beclin1 and p62 in H₂O₂-treated MG63 cells were detected by western blotting. An autophagy inhibitor was used to treat the MG63 cells, and whether miR-210 could affect the H₂O₂-treated MG63 cell phenotype through autophagy was investigated. The results demonstrated that H₂O₂ treatment promoted cell apoptosis and decreased cell viability, invasive ability and circKMT2D expression in MG63 and U2OS cells. Furthermore, circKMT2D knockdown decreased the cell viability and invasive ability and enhanced the apoptosis of H₂O₂-treated MG63 and U2OS cells. circKMT2D possessed binding sites for miR-210 and inhibited miR-210 expression. In H₂O₂-treated MG63 cells, miR-210 silencing partially reversed the circKMT2D knockdown-induced cell viability inhibition and apoptosis promotion. In addition, miR-210 elevated Beclin1 expression and decreased p62 expression in H₂O₂-treated MG63 cells. The use of the autophagy inhibitor partially reversed the miR-210 overexpression-induced promotion of apoptosis and inhibition of the viability and invasive ability of H₂O₂-treated MG63 cells. Taken together, these findings indicated that circKMT2D knockdown may contribute to the inhibition of H₂O₂-attenuated OS progression via miR-210/autophagy pathway.

Human mesenchymal stromal cells and derived extracellular vesicles: Translational strategies to increase their proangiogenic potential for the treatment of cardiovascular disease

Mesenchymal stromal cells (MSCs) offer great potential for the treatment of cardiovascular diseases (CVDs) such as myocardial infarction and heart failure. Studies have revealed that the efficacy of MSCs is mainly attributed to their capacity to secrete numerous trophic factors that promote angiogenesis, inhibit apoptosis, and modulate the immune response. There is growing evidence that MSC‐derived extracellular vesicles (EVs) containing a cargo of lipids, proteins, metabolites, and RNAs play a key role in this paracrine mechanism. In particular, encapsulated microRNAs have been identified as important positive regulators of angiogenesis in pathological settings of insufficient blood supply to the heart, thus opening a new path for the treatment of CVD. In the present review, we discuss the current knowledge related to the proangiogenic potential of MSCs and MSC‐derived EVs as well as methods to enhance their biological activities for improved cardiac tissue repair. Increasing our understanding of mechanisms supporting angiogenesis will help optimize future approaches to CVD intervention.

OSCC Exosomes Regulate miR-210-3p Targeting EFNA3 to Promote Oral Cancer Angiogenesis through the PI3K/AKT Pathway

This study is aimed at determining how oral squamous cell carcinoma (OSCC) regulates the angiogenesis of HUVECs through miR-210-3p expression and exploring the relationship among miR-210-3p, its target protein, and the possible mechanism of angiogenesis regulation. miR-210-3p expression was detected in OSCC tissues and juxta cancerous tissues (JCT), and the relationship among miR-210-3p, microvessel density (MVD), and histopathologic features was analyzed. A conditioned medium (CM) of the OSCC cell line CAL27 was collected to stimulate human umbilical vein endothelial cells (HUVECs), and the miR-210-3p levels and tube formation capability of HUVECs were measured. The target protein level of miR-210-3p was altered; then, PI3K/AKT pathway activation in HUVECs was detected. miR-210-3p was tested in exosomes separated from CAL27 CM, and the transfer of miR-210-3p from OSCC exosomes to HUVECs was verified. Then, we found that the OSCC tissues had higher miR-210-3p levels than the JCT, and miR-210-3p level was positively correlated with MVD and tumor grade. CAL27 CM was able to elevate miR-210-3p levels in HUVECs and promoted tube formation. EFNA3 was the target gene of miR-210-3p, and ephrinA3 protein level was able to influence the migration and proliferation of HUVECs. The levels of phosphorylated AKT in the HUVECs increased when ephrinA3 was downregulated, and the upregulation of ephrinA3 resulted in the suppression of the PI3K/AKT pathway. miR-210-3p was detected in exosomes isolated from the CM of CAL27 cells, and miR-210-3p level in the HUVECs was elevated after absorbing the OSCC exosomes. In conclusion, miR-210-3p was more overexpressed in OSCC tissues than in the JCT. The exosomes secreted by OSCC cells were able to upregulate miR-210-3p expression and reduce ephrinA3 expression in HUVECs and promoted tube formation through the PI3K/AKT signaling pathway.

RABL6A Is an Essential Driver of MPNSTs that Negatively Regulates the RB1 Pathway and Sensitizes Tumor Cells to CDK4/6 Inhibitors

PURPOSE

Malignant peripheral nerve sheath tumors (MPNST) are deadly sarcomas that lack effective therapies. In most MPNSTs, the retinoblastoma (RB1) tumor suppressor is disabled by hyperactivation of cyclin-dependent kinases (CDK), commonly through loss of CDK-inhibitory proteins such as p27(Kip1). RABL6A is an inhibitor of RB1 whose role in MPNSTs is unknown. To gain insight into MPNST development and establish new treatment options, we investigated RABL6A-RB1 signaling and CDK inhibitor-based therapy in MPNSTs.

EXPERIMENTAL DESIGN

We examined patient-matched MPNSTs and precursor lesions by RNA sequencing (RNA-Seq) and IHC. Molecular and biological effects of silencing RABL6A and/or p27 in MPNST lines and normal human Schwann cells were determined. Tumor-suppressive effects of CDK inhibitors were measured in MPNST cells and orthotopic tumors.

RESULTS

RABL6A was dramatically upregulated in human MPNSTs compared with precursor lesions, which correlated inversely with p27 levels. Silencing RABL6A caused MPNST cell death and G₁ arrest that coincided with p27 upregulation, CDK downregulation, and RB1 activation. The growth-suppressive effects of RABL6A loss, and its regulation of RB1, were largely rescued by p27 depletion. Importantly, reactivation of RB1 using a CDK4/6 inhibitor (palbociclib) killed MPNST cells in vitro in an RABL6A-dependent manner and suppressed MPNST growth in vivo. Low-dose combination of drugs targeting multiple RB1 kinases (CDK4/6, CDK2) had enhanced antitumorigenic activity associated with potential MPNST cell redifferentiation.

CONCLUSIONS

RABL6A is a new driver of MPNST pathogenesis that acts in part through p27-RB1 inactivation. Our results suggest RB1 targeted therapy with multiple pathway drugs may effectively treat MPNSTs.

Protective effect inhibiting the expression of miR-181a on the diabetic corneal nerve in a mouse model

To investigate the protective effect of inhibiting miR-181a on diabetic corneal nerve in mice, we chose male C57BL/6 mice with streptozotocin (STZ) -induced diabetes as animal models. The expression of miR-181a in trigeminal ganglion tissue (TG) of diabetic mice was detected by real-time PCR. In vitro, we cultured mouse trigeminal ganglion neurons and measured the neuronal axon growth when treated under miR-181a antagomir and negative conditions (NTC). Immunofluorescence showed a significant increase in neuronal axon length in trigeminal ganglion cells treated with miR-181a antagomir. In animal models, we performed epithelial scraping and subconjunctival injection of the miR-181a antagomir and miRNA antagomir NTC to observe the corneal nerve repair by corneal nerve staining. miR-181a antagomir subconjunctival injection significantly increased the corneal epithelium healing of diabetic mice compared with that of the NTC group. Meanwhile, corneal nerve staining showed that the repair of corneal nerve endings was significantly promoted. As the targets of the 181a, ATG5 and BCL-2 were previously identified. The results of Western blot showed that the expression of autophagy associated protein ATG5 and LC3B-II and the expression of anti-apoptotic protein Bcl-2 were decreased in the high-glucose cell culture environment and the diabetic TG tissue. The expression of ATG5, LC3B-II and Bcl-2 were significantly increased after miR-181a antagomir treatment compared with negative control group. This study showed that inhibition of miR-181a expression in diabetic mice could increase ATG5-mediated autophagic activation, BCL-2-mediated inhibition of apoptosis, and promote the growth of trigeminal sensory neurons and the regeneration of corneal nerve fibers. It has a protective effect on diabetic corneal neuropathy.

MiR-34c Participates in Diabetic Corneal Neuropathy Via Regulation of Autophagy

Purpose

To investigate the contribution and mechanism of miRNAs and autophagy in diabetic peripheral neuropathy.

Methods

In this study, we used streptozotocin (STZ)-induced type I diabetes C57 mice as animal models, and we detected the expression of miR-34c and autophagic intensity in trigeminal ganglion (TG) tissue. The bioinformatics software was used to predict and analyze the potential targets of miR-34c. Primary trigeminal ganglion neurons were cultured in vitro to investigate the effect of miR-34c on axon growth and survival of TG cells. A corneal epithelial damage-healing model was established on the diabetic mice, then miR-34c antagomir was injected subconjunctivally. The condition of corneal epithelial healing was observed through sodium fluorescein staining, and the peripheral nerve degeneration of the cornea was evaluated by β-tublin corneal nerve staining.

Results

The expression of miR-34c was significantly increased in TG tissue of type I diabetic mice by real-time PCR. Western blot showed that autophagy-related proteins Atg4B and LC3-II were significantly down-regulated in diabetes TG compared with normal control. Trigeminal neuron immunofluorescence showed that the length of the trigeminal ganglion cell synapses was significantly increased after miR-34c antagomir treatment compared with normal cultures. Subconjunctival injection of miR-34c antagomir can significantly promote corneal epithelium healing of diabetic mice and appreciably promote the regeneration of corneal nerve. At the same time, it can significantly increase the expression of autophagy in TG tissue of type I diabetic mice.

Conclusions

In this study , miR-34c was found to affect the growth of trigeminal sensory neurons and the repair of diabetic corneal nerve endings by acting directly on Atg4B.

Up-Regulation of hsa-miR-210 Promotes Venous Metastasis and Predicts Poor Prognosis in Hepatocellular Carcinoma

Objective: To investigate the potential biomarkers for venous metastasis of hepatocellular carcinoma (HCC), and briefly discuss their target genes and the signaling pathways they are involved in.

Materials and Method: The dataset GSE6857 was downloaded from GEO. Significantly differentially expressed miRNAs were identified using the R package “limma,” After that, the survival analysis was conducted to discover the significance of these up-regulated miRNAs for the prognosis of HCC patients. Additionally, miRNAs which were up-regulated in venous metastasis positive HCC tissues and were significant for the prognosis of HCC patients were further verified in clinical samples using RT-qPCR. The miRNAs were then analyzed for their correlations with clinical characteristics including survival time, AFP level, pathological grade, TNM stage, tumor stage, lymph-node metastasis, distant metastasis, child-pugh score, vascular invasion, liver fibrosis and race using 375 HCC samples downloaded from the TCGA database. The target genes of these miRNAs were obtained using a miRNA target gene prediction database, and their functions were analyzed using the online tool DAVID.

Results: 15 miRNAs were differentially expressed in samples with venous metastasis, among which 7 were up-regulated in venous metastasis positive HCC samples. As one of the up-regulated miRNAs, hsa-miR-210 was identified as an independent prognostic factor for HCC. Using RT-qPCR, it was evident that hsa-miR-210 expression was significantly higher in venous metastasis positive HCC samples (p = 0.0036). Further analysis indicated that hsa-miR-210 was positively associated with AFP level, pathological grade, TNM stage, tumor stage and vascular invasion. A total of 168 hsa-miR-210 target genes, which are mainly related to tumor metastasis and tumor signaling pathways, were also predicted in this study.

Conclusion: hsa-miR-210 might promote vascular invasion of HCC cells and could be used as a prognostic biomarker.

Potential role of HIF-1-responsive microRNA210/HIF3 axis on gemcitabine resistance in cholangiocarcinoma cells

MicroRNA-210 (miR-210) is a robust target for hypoxia-inducible factor, and its overexpression has been detected in a variety of solid tumors. However, the role of miR-210 in the development, progression and response to therapy in cholangiocarcinoma (CCA) remains undefined. We report here that high miR-210 expression was significantly correlated with the shorter survival of CCA patients. Overexpression of miR-210 inhibited CCA cell proliferation at the G2/M phase and reduced the gemcitabine sensitivity in CCA cells under CoCl₂-induced pseudohypoxia. Concomitantly, inhibition of endogenous miR-210 activity using miRNA sponges increased cell proliferation under CoCl₂-induced pseudohypoxia, resulting in an increase in gemcitabine sensitivity in CCA cells. We showed that HIF-3α, a negative controller of HIF-1α, was a target of miR-210 constituting a feed-forward hypoxic regulatory loop. Our data suggest an important role of miR-210 in sustaining HIF-1α activity via the suppression of HIF-3α, regulating cell growth and chemotherapeutic drug resistance in CCA.

Long non-coding RNA CTA sensitizes osteosarcoma cells to doxorubicin through inhibition of autophagy

Recently, several long non-coding RNAs (lncRNAs) have been implicated in osteosarcoma (OS). However, the regulatory roles of lncRNAs in chemotherapy resistance of OS still remain unclear. This study aimed to screen a novel lncRNA that contributes to chemotherapeutic resistance of OS, and to explore the underlying mechanisms. Our data showed that lncRNA CTA was markedly downregulated in OS tissues compared to their matched non-tumor tissues, and low expression of lncRNA CTA was significantly associated with the advanced clinical stage and tumor size. In addition, OS patients with low lncRNA CTA levels showed a worse prognosis when compared with those with high expression of lncRNA CTA. Furthermore, we report that lncRNA CTA has an inverse relationship with miR-210 expression in OS tissues. LncRNA CTA could be activated by doxorubicin (DOX), and could promote OS cell apoptosis by competitively binding miR-210, while inhibit cell autophagy. On the other hand, lncRNA CTA was downregulated in DOX-resistant OS cells. Overexpression of lncRNA CTA reduced autophagy and subsequently overcame DOX resistance of OS in vitro and in vivo. Therefore, we demonstrate that lncRNA CTA is an essential regulator in DOX-induced OS cell apoptosis, and the lncRNA CTA-miR-210 axis plays an important role in reducing OS chemoresistance.

Expression of microRNA 638 and sex-determining region Y-box 2 in hepatocellular carcinoma: Association between clinicopathological features and prognosis

The aim of the present study was to determine the expression profile of microRNA 638 (miR-638) and sex-determining region Y-box 2 (SOX2) in hepatocellular carcinoma (HCC), and to investigate their association with clinicopathological features and survival. Reverse transcription-quantitative polymerase chain reaction analysis was used to investigate miR-638 and SOX2 expression in 78 patients with HCC. Western blot and immunohistochemical analyses were performed in order to determine SOX2 protein expression in HCC samples. Combined with the clinical postoperative follow-up data, the expression of miR-638 and SOX2 and the association between this and the prognostic values of patients with HCC were statistically analyzed. The results of the present study confirmed that miR-638 expression in tumor tissues was significantly downregulated (P<0.001), while SOX2 expression was significantly increased, compared with healthy control tissues (P<0.05). In addition, a significant inverse correlation between miR-638 and SOX2 expression was also observed in the HCC tissues (r=-0.675; P<0.05). Clinicopathological correlation analysis demonstrated that reduced miR-638 and elevated SOX2 expression was significantly associated with the Tumor-Node-Metastasis stage and portal vascular invasion (P<0.05). However, no significant differences were observed in other clinicopathological features, including age, sex, tumor size, tumor differentiation and hepatitis status (P>0.05). Notably, follow-up analysis revealed that patients with HCC with low miR-638 expression and high SOX2 expression tended to have a significantly shorter postoperative survival time (P<0.001). It was concluded that miR-638 may serve a vital role in the occurrence and progression of HCC by regulating SOX2 expression and thus, that miR-638 and SOX2 may be critical as novel diagnostic and prognostic biomarkers for HCC.

Long non-coding RNA and tumor hypoxia: new players ushered toward an old arena

Hypoxia is a classic feature of the tumor microenvironment with a profound impact on cancer progression and therapeutic response. Activation of complex hypoxia pathways orchestrated by the transcription factor HIF (hypoxia-inducible factor) contributes to aggressive phenotypes and metastasis in numerous cancers. Over the past few decades, exponentially growing research indicated the importance of the non-coding genome in hypoxic tumor regions. Recently, key roles of long non coding RNAs (lncRNAs) in hypoxia-driven cancer progression have begun to emerge. These hypoxia-responsive lncRNAs (HRLs) play pivotal roles in regulating hypoxic gene expression at chromatic, transcriptional, and post-transcriptional levels by acting as effectors of the indirect response to HIF or direct modulators of the HIF-transcriptional cascade. Notably, the aberrant expression of HRLs significantly correlates with poor outcomes in cancer patients, showing promise for future utility as a tumor marker or therapeutic target. Here we address the latest advances made toward understanding the functional relevance of HRLs, the involvement of these transcripts in hypoxia response and the underlying action mechanisms, highlighting their specific roles in HIF-1 signaling regulation and hypoxia-associated malignant transformation.

MicroRNA-210 contributes to peripheral nerve regeneration through promoting the proliferation and migration of Schwann cells

Peripheral nerve injury impacts the daily life of affected individuals. MicroRNA (miR)-210 is a multifunctional miR and has effects on the proliferation, migration and differentiation of cells. However, whether miR-210 has effects on peripheral nerve regeneration has remained elusive. In the present study, the miR-210 levels in a rat model of sciatic nerve injury were evaluated by reverse-transcription quantitative PCR and the effects of miR-210 on the proliferation and migration of Schwann cells were explored. Elevated miR-210 levels were discovered in the sciatic nerve injury rat model. miR-210 mimics were found to promote the proliferation and migration of Schwann cells, while miR-210 inhibitor was found to inhibit the proliferation and migration of Schwann cells. Further study showed that miR-210 had effects on the expression of growth-associated protein-43, myelin-associated glycoprotein and myelin basic protein. These results showed that miR-210 had effects on the proliferation and migration of Schwann cells and may be involved in the peripheral nerve regeneration.

Identification of novel diagnostic and prognostic miRNA signatures in endometrial cancer

With the goal of identifying diagnostic and prognostic biomarkers in endometrial cancer, miRNA-profiling was carried out with formalin-fixed paraffin embedded (FFPE) tissue samples from 49 endometrial cancer patients. Results using an 84-cancer specific miRNA panel identified the upregulation of miR-141-3p and miR-96-5p along with a downregulation of miR-26, miR-126-3p, miR-23b, miR-195-5p, miR-374a and let-7 family of miRNAs in endometrial cancer. We validated the dysregulated expression of the identified miRNAs in a panel of endometrial cancer cell-lines. Immunohistochemical analysis of the tissue micro array derived from these patients established the functional correlation between the decreased expression of tumor suppressive miRNAs and their target oncogenes: ERBB2, EGFR, EPHA2, BAX, GNA12, GNA13, and JUN. Comparative analysis of the samples from the patients with extended progression-free survival (PFS) ( > 21 months) versus the patients with the PFS of < 21 months indicated increased expression of tumor suppressive miR-142-3p, miR-142-5p, and miR-15a-5p in samples from extended PFS patients. In addition to defining a specific set of miRNAs and their target genes as potential diagnostic biomarkers, our studies have identified tumor suppressive miR-142 cluster and miR-15a as predictors of favorable prognosis for therapy response in endometrial cancer.

MicroRNA-215 acts as a tumor suppressor in breast cancer by targeting AKT serine/threonine kinase 1

There are accumulating reports that microRNAs are dysregulated in a number of human cancer types, and that they may function as tumor suppressors or oncogenes in tumorigenesis and tumor development. microRNA-215 (miR-215) has been identified as a tumor suppressor in epithelial ovarian, pancreatic, non-small cell lung and colon cancer, whereas it may act as an oncogene in gastric and cervical cancer. The role of miR-215 in breast cancer carcinogenesis and progression has yet to be elucidated. In the present study, the expression level of miR-215 was determined in breast cancer tissues and cell lines using the reverse transcription-quantitative polymerase chain reaction. The effects of miR-215 overexpression on proliferation and the invasive capacity of breast cancer cells were assessed using MTT and cell invasion assays. The results revealed that miR-215 was significantly downregulated in breast cancer tissues and cell lines. Restoration of miR-215 expression inhibited the proliferation and invasion of breast cancer cells. The underlying molecular mechanism for the suppression of proliferation and invasion by miR-215 was investigated. AKT serine/threonine kinase 1 (AKT1) was validated as a novel direct target of miR-215, and the effect of AKT1 small interfering RNA mimicked the effect of miR-215 overexpression in breast cancer cells. These results indicated that miR-215 acted as a tumor suppressor, and that its downregulation in tumor tissues may contribute to the carcinogenesis and progression of breast cancer, indicating that miR-215 may be a novel therapeutic target for the treatment of breast cancer.

MicroRNA-10b inhibits proliferation, migration and invasion in cervical cancer cells via direct targeting of insulin-like growth factor-1 receptor

MicroRNAs are deregulated in numerous types of human cancers and have crucial roles in the carcinogenesis and progression of human cancers. MicroRNA-10b (miR-10b) has been studied in several types of human cancer. However, the expression and roles of miR-10b in cervical cancer remain unknown. In the present study, the expression, functions and molecular mechanisms of miR-10b were explored in cervical cancer. The present data revealed that miR-10b was significantly downregulated in cervical cancer tissues and cell lines. In addition, miR-10b overexpression inhibited the proliferation, migration and invasion of cervical cancer cells, while miR-10b under-expression had the opposite effect. Based on bioinformatics analysis, a luciferase reporter assay and western blot analysis, insulin-like growth factor-1 receptor (IGF-1R) was identified as a direct target of miR-10b in cervical cancer. In addition, IGF-1R small interfering RNA-mediated knockdown of IGF-1R also inhibited the proliferation, migration and invasion of the cervical cancer cells. In conclusion, the present study demonstrated that miR-10b serves an important role in cervical cancer progression by targeting IGF-1R.

Hypoxia-induced miR-210 promoter demethylation enhances proliferation, autophagy and angiogenesis of schwannoma cells

Hypoxia, a dominant feature in cancer occurrence and evolution, exists throughout the progression of most malignant tumors. This study focused on the mechanism of hypoxia-induced miR-210 upregulation, and the miR-210 functions in schwannoma. We detected microvascular density, vascular endothelial growth factor (VEGF) and miR-210 expression levels using schwannoma tissue mciroarray. The results showed that miR-210 expression was significantly associated with VEGF. Moreover, the cytological tests showed that hypoxia induced miR-210 expression, while reduce ephrin-A3 expression. The bisulfate genomic sequencing PCR results showed that miR-210 promoter region was hypermethylated in RT4-D6P2T in normoxia, while demethylated in hypoxia, and the region included the hypoxia-inducible factor-1α (HIF-1α) response element site. Cellular function research showed that hypoxia resulted in RT4-D6P2T apoptosis, higher autophage and invasion. Besides, hypoxia can affect HIF-1α/VEGF-mediated angiogenesis. To learn about the specific functions of miR-210, we found that with miR-210 inhibition, tumor cell apoptosis increased, autophagy and angiogenesis reduced, and the cell cycle was arrested. Hypoxia promoted miR-210 expression through promoter demethylation, then consequently enhanced tumor cell proliferation and autophagy, increasing tumor cell angiogenesis. Thus, miR-210 could be a potential marker for judging tumor malignancy and be taken as an effective target for clinical auxiliary treatment of neurilemmoma.

Role of Epigenetics in Uveal Melanoma

Uveal melanoma (UM) is a severe human malignancy with a high mortality rate that demands continued research into new and alternative forms of prevention and treatment. The emerging field of epigenetics is beginning to unfold an era of contemporary approaches to reducing the risk and improving the clinical treatment of UM. Epigenetic changes have a high prevalence rate in cancer, are reversible in nature, and can lead to cancer characteristics even in mutation-free cells. The information contained in this review highlights and expands on the main mechanisms of epigenetic dysregulation in UM tumorigenesis, progression and metastasis, including microRNA expression, hypermethylation of genes and histone modification. Epigenetic drugs have been shown to enhance tumor suppressor gene expression and drug sensitivity in many other cancer cell lines and animal models. An increased understanding of epigenetic mechanisms in UM will be invaluable in the design of more potent epigenetic drugs, which when used in combination with traditional therapies, may permit improved therapeutic outcomes.

The tumour hypoxia induced non-coding transcriptome

Recent investigations have highlighted the importance of the non-coding genome in regions of hypoxia in tumours. Such regions are frequently found in solid tumours, and are associated with worse patient survival and therapy resistance. Hypoxia stabilises the transcription factors, hypoxia inducible factors (HIF1α and HIF2α) which coordinate transcriptomic changes that occur in hypoxia. The changes in gene expression induced by HIF1α and HIF2α contribute to many of the hallmarks of cancer phenotypes and enable tumour growth, survival and invasion in the hypoxic tumour microenvironment. Non-coding RNAs, in particular microRNAs (miRNAs), which regulate mRNA stability and translation, and long-non-coding RNAs (lncRNAs), which have diverse functions including chromatin modification and transcriptional regulation, are also important in enabling the key hypoxia regulated processes. They have roles in the regulation of metabolism, angiogenesis, autophagy, invasion and metastasis in the hypoxic microenvironment. Furthermore, HIF1α and HIF2α expression and stabilisation are also regulated by both miRNAs and lncRNAs. Here we review the recent developments in the expression, regulation and functions of miRNAs, lncRNAs and other non-coding RNA classes in tumour hypoxia.

MicroRNAs and Endothelial (Dys) Function

Accumulating evidence indicates that microRNAs (miRs)-non-coding RNAs that can regulate gene expression via translational repression and/or post-transcriptional degradation-are becoming one of the most fascinating areas of physiology, given their fundamental roles in countless pathophysiological processes. The relative roles of different miRs in vascular biology as direct or indirect post-transcriptional regulators of fundamental genes implied in vascular remodeling designate miRs as potential biomarkers and/or promising drug targets. The mechanistic importance of miRs in modulating endothelial cell (EC) function in physiology and in disease is addressed here. Drawbacks of currently available therapeutic options are also discussed, pointing at the challenges and clinical opportunities provided by miR-based treatments. J. Cell. Physiol. 231: 1638-1644, 2016. © 2015 Wiley Periodicals, Inc.

microRNA-762 promotes breast cancer cell proliferation and invasion by targeting IRF7 expression

OBJECTIVES

miRNAs play crucial roles in human tumourigenesis. This study was performed to measure expression and function of miR-762 in breast cancer.

MATERIALS AND METHODS

Expression of miR-762 in breast tissues and cell lines (SK-BR-3, DA-MB-435s, MCF-7 and MDA-MB-231, HBL-100) was measured by using real-time RT-PCR. We restored expression of miR-762 in MCF-7 cells to measure its functional roles. Luciferase assays were performed to reveal the target gene of miR-762.

RESULTS

Expression of miR-762 was high in both breast cancer cell lines and specimens, and its overexpression increased breast cancer cell proliferation and invasion. Interferon regulatory factor 7 (IRF7) is a direct target of miR-762 and overexpression of miR-762 reduced expression of IRF7. Moreover, IRF7 was repressed, its levels inversely correlated to miR-762 expression. IRF7 rescued miR-762-induced cell invasion and proliferation.

CONCLUSIONS

These results demonstrate that miR-762 tumour effect was achieved by targeting IRF7 in human breast cancer specimens.

The MicroRNA-217 Functions as a Potential Tumor Suppressor in Gastric Cancer by Targeting GPC5

Gastric cancer (GC) is one of the most common malignancies worldwide. Emerging evidence has shown that aberrant expression of microRNAs (miRNAs) plays important roles in cancer progression. However, little is known about the potential role of miR-217 in GC. In this study, we investigated the role of miR-217 on GC cell proliferation and invasion. The expression of miR-217 was down-regulated in GC cells and human GC tissues. Enforced expression of miR-217 inhibited GC cells proliferation and invasion. Moreover, Glypican-5 (GPC5), a new ocncogene, was identified as the potential target of miR-217. In addition, overexpression of miR-217 impaired GPC5-induced promotion of proliferation and invasion in GC cells. In conclusion, these findings revealed that miR-217 functioned as a tumor suppressor and inhibited the proliferation and invasion of GC cells by targeting GPC5, which might consequently serve as a therapeutic target for GC patients.

Dissecting the roles of Ephrin-A3 in malignant peripheral nerve sheath tumor by TALENs

Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue sarcoma for which effective treatments have not yet been established due to poor understanding of its pathogenesis. Our previous study indicated that miR-210-mediated Ephrin-A3 (EFNA3) promotion of proliferation and invasion of MPNST cells plays an important role in MPNST tumorigenesis and progression. The purpose of the present study was to further investigate the roles of EFNA3 in MPNST. Constructed transcription activator-like effector nucleases (TALENs) and lentiviral vectors were transfected into MPNST ST88-14 (NF1 wild-type) and sNF96.2 (NF1 mutant type) cell lines to obtain gain- and loss-of-function cell lines for the EFNA3 function study. The results showed that the knockout of ENFA3 increased cellular viability and invasiveness of the MPNST cells. However, the adhesion ability of MPNST cells was enhanced or inhibited when EFNA3 was overexpressed or knocked out, respectively. It was also observed that knockout of EFNA3 significantly decreased the expression of phosphorylated FAK (p-FAK) and the tumor necrosis factor α (TNF-α) compared to that in the control cells, yet the expression of phosphatidylinositol 3-kinase (PI3K), GTPase, integrins, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1α (HIF-α) increased significantly. Inversely, overexpression of EFNA3 significantly increased the expression of p-FAK and TNF-α compared to that in the control cells, yet the expression of PI3K, GTPase, integrins, VEGF and HIF-α decreased significantly. The results indicated that EFNA3 serves as a tumor suppressor in MPNST cells and it may play a critical role in the focal adhesion kinase (FAK) signaling and VEGF-associated tumor angiogenesis pathway. These findings may not only facilitate the better understanding of MPNST pathogenesis, but also suggest EFNA3 as a promising target for MPNST treatment.

Serum microRNA-210 as a potential noninvasive biomarker for the diagnosis and prognosis of glioma

BACKGROUND

MicroRNA-210 (miR-210) is an oncogenic miRNA previously associated with prognosis in human gliomas, an incurable tumour type of the central nervous system. Here miR-210 was investigated as a potential serum biomarker in the diagnosis and prognosis of glioma.

METHODS

Serum was immediately prepared from blood samples collected from patients with glioma grades I-IV at primary diagnosis (n=136) and healthy controls (n=50) from February 2007 to March 2014 in the Department of Neurosurgery of the First Affiliated Hospital of Wannan Medical College (Wuhu, China). Total RNA was isolated from serum. cDNA was synthesised with primers specific for miR-210 and miR-16-1 (internal control), and quantitative real-time RT-PCR was performed. Results were statistically analysed to determine the role of miR-210 in the diagnosis and prognosis of human glioma patients.

RESULTS

An approximately seven-fold increase in miR-210 expression was detected in serum samples from glioblastoma patients relative to healthy controls. A threshold expression value (2.259) was chosen from receiver operator characteristic curves (ROC), and the low and high miR-210 expression groups were analysed by multivariate Cox proportional hazard regression and Kaplan-Meier analyses. Results revealed an association of high serum miR-210 expression with tumour grade and poor patient outcome (P-values <0.001).

CONCLUSIONS

Serum miR-210 is a promising diagnostic and prognostic biomarker that can be detected in the peripheral blood of patients with glioma.

miR-709 up-regulated in hepatocellular carcinoma, promotes proliferation and invasion by targeting GPC5

OBJECTIVES

Hepatocellular carcinoma (HCC) is one of the most common cancers and is a significant leading cause of cancer-related deaths worldwide. Emerging evidence has shown that microRNAs (miRNAs) are associated with cancer development and progression. However, up to now little has been known concerning the role of miR-709 in HCC.

MATERIALS AND METHODS

Real-time RT-PCR was performed to detect expression of miR-709 in HCC cell lines and tissues. To further understand its role in HCC, we restored its expression in HepG2 cell line through transfection with miR-709 mimics or inhibitors. CCK-8 proliferation assay, migration assay and invasion assay were used to detect functional roles of miR-709. Luciferase assay and western blotting were performed to detect the target gene of miR-709.

RESULTS

We found that miR-709 was highly expressed in HCC tissues and in HCC cell lines by qRT-PCR. Re-expression of miR-709 in HCC cells remarkably promoted cell migration and invasiveness in vitro. Subsequent investigation revealed that glypican-5 (GPC5) was a direct and functional target of miR-709 in HCC cells where overexpression of miR-709 impaired GPC5-induced inhibition of proliferation and invasion. Finally, analysis of miR-709 and GPC5 levels in human HCC tissues revealed that miR-709 inversely correlated with GPC5 expression.

CONCLUSIONS

These results suggest that miR-709 may positively regulate invasion and metastasis of HCC through targeting GPC5.

MicroRNA dysregulation in uveal melanoma: a new player enters the game

Uveal melanoma is the second most common form of melanoma and a predominant intraocular malignant tumor in adults. The development of uveal melanoma is a multistep process involving genetic and epigenetic alteration of proto-oncogenes and tumor-suppressor genes. Recent discoveries have shed a new light on the involvement of a class of noncoding RNA known as microRNAs (miRNAs) in uveal melanoma. A lot of miRNAs show differential expressions in uveal melanoma tissues and cell lines. Genes coding for these miRNAs have been characterized as novel oncogene and tumor-suppressor genes based on findings that these miRNAs control malignant phenotypes of uveal melanoma cells. Several studies have confirmed that dysregulation of miRNAs promotes cell-cycle progression, confers resistance to apoptosis, and enhances invasiveness and metastasis. Moreover, several miRNAs have also been shown to correlate with uveal melanoma initiation and progression, and thus may be used as biomarkers for early diagnosis and prognosis. Elucidating the biological aspects of miRNA dysregulation may help us better understand the pathogenesis of uveal melanoma and promote the development of miRNA directed-therapeutics against this disease.

microRNAs Distinctively Regulate Vascular Smooth Muscle and Endothelial Cells: Functional Implications in Angiogenesis, Atherosclerosis, and In-Stent Restenosis

Endothelial cells (EC) and vascular smooth muscle cells (VSMC) are the main cell types within the vasculature. We describe here how microRNAs (miRs)--noncoding RNAs that can regulate gene expression via translational repression and/or post-transcriptional degradation--distinctively modulate EC and VSMC function in physiology and disease. In particular, the specific roles of miR-126 and miR-143/145, master regulators of EC and VSMC function, respectively, are deeply explored. We also describe the mechanistic role of miRs in the regulation of the pathophysiology of key cardiovascular processes including angiogenesis, atherosclerosis, and in-stent restenosis post-angioplasty. Drawbacks of currently available therapeutic options are discussed, pointing at the challenges and potential clinical opportunities provided by miR-based treatments.

MicroRNA expression and its clinical implications in Ewing's sarcoma

Ewing's sarcoma (EWS) is the second most common primary bone cancer, and is a predominant childhood malignant disease. Due to limited understanding of its pathogenesis and frequent occurrence of resistance to conventional types of treatment, its management remains difficult, and mortality is frequent. Development of EWS is a multistep process involving genetic and epigenetic alterations of protein-coding proto-oncogenes and tumour-suppressor genes. MicroRNAs (miRNAs) have recently been discovered as a new category of non-protein coding; small RNA molecules that regulate gene expression at the post-transcriptional level. Substantial numbers of deregulated miRNAs have been documented in EWS and their biological significance has been confirmed in multiple functional experiments. Several studies have confirmed involvement of miRNAs in various steps of EWS pathogenesis, from occurrence to metastasis. Functionally, miRNA dysregulation may promote cell-cycle progression, confer resistance to apoptosis, and enhance invasiveness and metastasis. These miRNAs have opened a novel field in cancer research with potential clinical utilization for screening, diagnosis, prognostics and prediction of response to treatment. Elucidating biological aspects of miRNA dysregulation may help better understand pathogenesis of EWS and promote development of miRNA directed-therapeutics against it.

MiR-210 up-regulation inhibits proliferation and induces apoptosis in glioma cells by targeting SIN3A

Background

The aim of this study was to determine whether miR-210 can affect the apoptosis and proliferation of human U251 glioma cells from down-regulating SIN3A.

Material/Methods

The expression of miRNA-210 was detected by quantitative real-time PCR in normal brain tissue and glioma samples. The apoptosis and proliferation ability of U251 cells were analyzed by MTT and flow cytometry assay after anti-miR-210 transfection. For the regulation mechanism analysis of miR-210, TargetScan, PicTar, and microRNA were selected to predict some potential target genes of miR-210. The predicted gene was identified to be the direct and specific target gene of miR-210 by luciferase activities assay and Western blot. RNA interference technology was used to confirm that the apoptosis and proliferation effects of miR-210 were directly induced by SIN3A.

Results

The expression of miR-210 increased significantly in glioma in comparison with normal brain tissue. The silence of miR-210 expression could inhibit the proliferation of U251 cells and induce the apoptosis. Mechanism analysis revealed that SIN3A was a specific and direct target gene of miR-210. The siRNA-SIN3A could down-regulate the expression of SIN3A protein, which was up-regulated in U251 cells by anti-miR-210 transfection, and our experiments found that silence of SIN3A could inhibit the apoptosis and sharply increase the proliferation of U251 cells. The regulation effects of anti-miR-210 on apoptosis and proliferation can be reversed respectively by the expression silence of SIN3A.

Conclusions

Aberrantly expressed miR-210 regulates human U251 glioma cells apoptosis and proliferation partly through directly down-regulating SIN3A protein expression. This might offer a new potential therapeutic stratagem for glioma.