VEGF-Induced Expression of miR-17-92 Cluster in Endothelial Cells Is Mediated by ERK/ELK1 Activation and Regulates Angiogenesis

MiRNA505/NET1 Axis Acts as a CD8+ T-TIL Regulator in Non-Small Cell Lung Cancer

Introduction

Lung adenocarcinoma (LUAD), which is the most important and common subtype of non-small cell lung cancer (NSCLC), is highly heterogeneous with a poor prognosis and poses great challenges to health worldwide. MicroRNAs (miRNAs) are regulators of gene expression with recognized roles in physiology and diseases, such as cancers, but little is known about their functional relevance to CD8⁺ T cell infiltration regulation in the tumor microenvironment (TME) of NSCLC patients, especially LUAD patients.

Methods

Bioinformatic analysis was used to analyze TCGA data. RT-PCT, Western blot, luciferase assay and immunohistochemistry were used to detect the expression levels and bindings of genes and miRNA. ELISA and cytotoxic assay were used to evaluate CD8⁺ T cell function.

Results

In this study, bioinformatic analysis unveiled the miR-505-3p/NET1 pair as a CD8⁺ T-tumor-infiltrating lymphocyte (TIL) regulator. Then, we confirmed the bioinformatic results with LUAD patient samples, and NET1 was shown to be a direct target of miR-505-3p in a luciferase assay. Functional experiments demonstrated that miR-505-3p enhanced CD8⁺ T-TIL function, while NET1 impaired CD8⁺ T-TIL function and partly reversed the effects of miR-505-3p. The observed effects might be exerted via the regulation of immunosuppressive receptors in T cells.

Discussion

Our study may provide novel insights into LUAD progression related to the TME mechanism and new possibilities for improving adoptive immunotherapy.

The role of microenvironment in tumor angiogenesis

Tumor angiogenesis is necessary for the continued survival and development of tumor cells, and plays an important role in their growth, invasion, and metastasis. The tumor microenvironment—composed of tumor cells, surrounding cells, and secreted cytokines—provides a conducive environment for the growth and survival of tumors. Different components of the tumor microenvironment can regulate tumor development. In this review, we have discussed the regulatory role of the microenvironment in tumor angiogenesis. High expression of angiogenic factors and inflammatory cytokines in the tumor microenvironment, as well as hypoxia, are presumed to be the reasons for poor therapeutic efficacy of current anti-angiogenic drugs. A combination of anti-angiogenic drugs and antitumor inflammatory drugs or hypoxia inhibitors might improve the therapeutic outcome.

Proliferation of Vascular Smooth Muscle Cells under ox-LDL Is Regulated by Alismatis rhizoma Decoction via InhibitingERK1/2 and miR-17∼92a Cluster Activation

Context: Alismatis rhizome decoction (AD) exhibits antiatherosclerotic activities. The activity of AD against vascular smooth muscle cell (VSMC) proliferation remains unclear. Objective. The mechanisms and effects of AD on oxidized low-density lipoprotein (ox-LDL)-induced VSMC proliferation were explored. Materials and methods. The male SD rats were fed with AD (2.56 g/mL) or 0.9% NaCl by oral gavage 4 mL twice daily for 7 d. Then, AD-containing serum (ADcs) was collected. MTS assay was applied to measure the VSMC viability. The proliferation of VSMCs was detected by 5-bromodeoxyuridine (BrdU) immunocytochemistry. The microRNA (miRNA) profiling was performed, and the target genes of miRNAs were searched from the TargetScan 7.2 database. The expressions of matrix metalloproteinases-2/9 (MMP-2/9), cyclin D1/E, cyclin-dependent kinase inhibitor 1B (p27), extracellular regulated protein kinases 1/2 (ERK1/2), and ERK1/2 phosphorylation were examined by western blotting or quantitative reverse transcription PCR. Results. The ox-LDL-induced miR-17-92a expression promoted VSMC proliferation. AD and the ERK1/2 inhibitor U0126 (10 μmol/L) inhibited VSMC proliferation and reduced the overexpression of miR-17∼92a. AD was found to inhibit phosphorylation of ERK1/2 and reduced the expression of MMP-2/9 in VSMCs. The expression of cyclin D1/E was suppressed, and p27 was elevated following treatment with AD as well as ERK1/2 inhibitor. According to the TargetScan 7.2 database, the target genes of miR-17∼92a act on tissue inhibitors of metalloproteinases (TIMPs)-MMPs, p27/21 cyclins, and peroxisome-proliferator-activated receptor α (PPARα) ATP-binding cassette transporter (ABC) A1/G1, which are involved in the process of atherosclerosis. Conclusions. AD inhibits ox-LDL-induced VSMC proliferation via inhibiting ERK1/2 and miR-17∼92a activation. The results provide the multitarget mechanisms for application of AD in the treatment of atherosclerosis. It would be helpful to the treatment of cardiovascular and cerebral diseases.

MicroRNAs and obesity-induced endothelial dysfunction: key paradigms in molecular therapy

The endothelium plays a pivotal role in maintaining vascular health. Obesity is a global epidemic that has seen dramatic increases in both adult and pediatric populations. Obesity perturbs the integrity of normal endothelium, leading to endothelial dysfunction which predisposes the patient to cardiovascular diseases. MicroRNAs (miRNAs) are short, single-stranded, non-coding RNA molecules that play important roles in a variety of cellular processes such as differentiation, proliferation, apoptosis, and stress response; their alteration contributes to the development of many pathologies including obesity. Mediators of obesity-induced endothelial dysfunction include altered endothelial nitric oxide synthase (eNOS), Sirtuin 1 (SIRT1), oxidative stress, autophagy machinery and endoplasmic reticulum (ER) stress. All of these factors have been shown to be either directly or indirectly caused by gene regulatory mechanisms of miRNAs. In this review, we aim to provide a comprehensive description of the therapeutic potential of miRNAs to treat obesity-induced endothelial dysfunction. This may lead to the identification of new targets for interventions that may prevent or delay the development of obesity-related cardiovascular disease.

Hepatocyte Growth Factor and Macrophage-stimulating Protein "Hinge" Analogs to Treat Pancreatic Cancer

Pancreatic cancer (PC) ranks twelfth in frequency of diagnosis but is the fourth leading cause of cancer related deaths with a 5 year survival rate of less than 7 percent. This poor prognosis occurs because the early stages of PC are often asymptomatic. Over-expression of several growth factors, most notably vascular endothelial growth factor (VEGF), has been implicated in PC resulting in dysfunctional signal transduction pathways and the facilitation of tumor growth, invasion and metastasis. Hepatocyte growth factor (HGF) acts via the Met receptor and has also received research attention with ongoing efforts to develop treatments to block the Met receptor and its signal transduction pathways. Macrophage-stimulating protein (MSP), and its receptor Ron, is also recognized as important in the etiology of PC but is less well studied. Although the angiotensin II (AngII)/AT1 receptor system is best known for mediating blood pressure and body water/electrolyte balance, it also facilitates tumor vascularization and growth by stimulating the expression of VEGF. A metabolite of AngII, angiotensin IV (AngIV) has sequence homology with the "hinge regions" of HGF and MSP, key structures in the growth factor dimerization processes necessary for Met and Ron receptor activation. We have developed AngIV-based analogs designed to block dimerization of HGF and MSP and thus receptor activation. Norleual has shown promise as tested utilizing PC cell cultures. Results indicate that cell migration, invasion, and pro-survival functions were suppressed by this analog and tumor growth was significantly inhibited in an orthotopic PC mouse model.

VEGFA and NFE2L2 Gene Expression and Regulation by MicroRNAs in Thyroid Papillary Cancer and Colloid Goiter

Deregulation of VEGFA (Vascular Endothelial Growth Factor A) and NFE2L2 (Nuclear Factor (Erythroid-derived 2)-Like 2), involved in angiogenesis and oxidative stress, can lead to thyroid cancer progression. MiR-17-5p and miR-612 are possible regulators of these genes and may promote thyroid disorders. In order to evaluate the involvement of VEGFA, NFE2L2, hsa-miR-17-5p, and hsa-miR-612 in thyroid pathology, we examined tissue samples from colloid goiter, papillary thyroid cancer (PTC), and a normal thyroid. We found higher levels of VEGFA and NFE2L2 transcripts and the VEGFA protein in goiter and PTC samples than in normal tissue. In the goiter, miR-612 and miR-17-5p levels were lower than those in PTC. Tumors, despite showing lower VEGFA mRNA expression, presented higher VEGFA protein levels compared to goiter tissue. In addition, NRF2 (Nuclear Related Transcription Factor 2) protein levels in tumors were higher than those in goiter and normal tissues. Inhibition of miR-17-5p resulted in reduced NFE2L2 expression. Overall, both transcript and protein levels of NFE2L2 and VEGFA were elevated in PTC and colloid goiter. Hsa-miR-612 showed differential expression in PTC and colloid goiter, while hsa-miR-17-5p showed differential expression only in colloid goiter, suggesting that hsa-miR-17-5p may be a positive regulator of NFE2L2 expression in PTC.

Blood microRNA expressions in patients with mild to moderate psoriasis and the relationship between microRNAs and psoriasis activity

Background

In recent studies, microRNAs (mi-RNAs) have been shown to play an important role in psoriasis pathogenesis. However, studies evaluating mi-RNAs in the blood of psoriasis patients including a large number of mi-RNA panels are scarce.

Objective

The authors aimed to assess mi-RNA expressions in blood samples of psoriasis patients, as well as to evaluate the association between mi-RNA expression and psoriasis severity.

Methods

This was a case-control study on 52 patients with psoriasis vulgaris and 54 controls. Patients’ medical history, psoriasis area and severity index (PASI) scores, and dermatology life quality index (DLQI) scores were recorded. The 42 disease-related mi-RNA primers were assessed by real-time PCR.

Results

In the patient group, 13.4% presented nail involvement and 8.2% had psoriatic arthritis. The mean PASI and DLQI scores were 7.90 ± 8.83 and 8.13 ± 5.50, respectively. Among 42 mi-RNA primers; hsa-miR-155-5p, hsa-miR-369-3p, hsa-miR-193b-3p, hsa-miR-498, hsa-miR-1266-5p, hsa-let-7d-5p, hsa-miR-205-5p, hsa-let-7c-5p, hsa-miR-30b-3p, and hsa-miR-515-3p expressions were significantly up-regulated, whereas hsa-miR-21-5p, hsa-miR-142-3p, hsa-miR-424-5p, hsa-miR-223-3p, hsa-miR-26a-5p, hsa-miR-106b-5p, hsa-miR-126-5p, hsa-miR-181a-5p, hsa-miR-222-3p, hsa-miR-22-3p, hsa-miR-24-3p, hsa-miR-17-3p, hsa-miR-30b-5p, hsa-miR-130a-3p, hsa-miR-30e-5p, and hsa-miR-16-5p were significantly down-regulated in psoriasis patients when compared with the control group (p < 0.05).

Study limitations

As the study included patients with mild to moderate psoriasis who mostly only received topical treatments, changes in miRNA before and after systemic treatments were not assessed.

Conclusion

The detection of 24 mi-RNA expressions up- or down-regulated in psoriasis patients, even in those with milder disease, further supports the role of mi-RNAs in the psoriasis pathogenesis. Future studies should clarify whether mi-RNAs can be used as a marker for psoriasis prognosis or as a therapeutic agent in the treatment of psoriasis.

Impact of Phenol-Enriched Virgin Olive Oils on the Postprandial Levels of Circulating microRNAs Related to Cardiovascular Disease

SCOPE

We investigate the postprandial modulation of cardiovascular-related microRNAs elicited by extra virgin olive oil (EVOOs) containing different levels of their own polyphenols.

METHODS AND RESULTS

It is randomized, postprandial, parallel, double-blind study. Twelve healthy participants consumed 30 mL of EVOO containing low (L-EVOO; 250 mg total phenols kg-1 of oil), medium (M-EVOO; 500 mg total phenols kg-1 of oil), and high (H-EVOO; 750 mg total phenols kg-1 of oil) enriched EVOOs. Postprandial plasma microRNAs levels are analyzed by real-time quantitative PCR. The results show that L-EVOO intake is associated with decreased let-7e-5p and miR-328a-3p levels and increased miR-17-5p and miR-20a-5p, concentrations. M-EVOO decreases plasma let-7e-5p and increases miR-17-5p, miR-20a-5p, and miR-192-5p levels. Finally, H-EVOO decreases let-7e-5p, miR-10a-5p, miR-21-5p, and miR-26b-5p levels.

CONCLUSION

During the postprandial state, the levels of let-7e-5p decrease with EVOO regardless of polyphenol content suggesting a general response to the fatty acid composition of EVOO or/and the presence of at least 250 mg polyphenol kg-1 olive oil. Moreover, the miR-17-92 cluster increases by low and medium polyphenol content suggesting a role in fatty acid metabolism and nutrient sensing. Thus, postprandial modulation of circulating microRNAs levels could be a potential mechanism for the cardiovascular benefits associated with EVOO intake.

Inhibition of miR-17~92 Cluster Ameliorates High Glucose-Induced Podocyte Damage

The loss and damage of podocytes is an early feature of diabetic nephropathy (DN). The miR-17∼92 cluster was dysregulated in diabetic and polycystic kidney disease patients, but its role in DN is unclear. Hence, an in vitro study on the high glucose- (HG-) treated mouse podocytes (MPC5) was designed to elucidate the effect of miR-17∼92 cluster downregulation on cell viability, apoptosis, inflammation, fibrosis, and podocyte function. The results suggested that the miR-17∼92 cluster members miR-17-5p, miR-18a, miR-19a, miR-19b, miR-20a, and miR-92a were upregulated in the renal biopsy tissue of DN patients and HG-treated MPC5. The downregulation of the miR-17∼92 cluster effectively suppressed the cell apoptosis, inflammation, fibrosis, and podocyte dysfunction in HG-stimulated MPC5 cells. The bioinformatics analysis and rescue experiments showed that ABCA1 (ATP-binding cassette transporter A1) is an effector of the miR-17~92 cluster. Silence of ABCA1 inhibited the protective effect of the miR-17∼92 cluster downregulation on podocyte damage. In summary, this research indicated that the downregulation of the miR-17∼92 cluster ameliorates HG-induced podocyte damage via targeting ABCA1.

Circ-ADAM9 targeting PTEN and ATG7 promotes autophagy and apoptosis of diabetic endothelial progenitor cells by sponging mir-20a-5p

Dysfunction of endothelial progenitor cells (EPCs) is a key factor in vascular complications of diabetes mellitus. Although the roles of microRNAs and circular RNAs in regulating cell functions have been thoroughly studied, their role in regulating autophagy and apoptosis of EPCs remains to be elucidated. This study investigated the roles of mir-20a-5p and its predicted target circ-ADAM9 in EPCs treated with high glucose (30 mM) and in a diabetic mouse hind limb ischemia model. It is found that Mir-20a-5p inhibited autophagy and apoptosis of EPCs induced by high-concentration glucose. Further, mir-20a-5p could inhibit the expression of PTEN and ATG7 in EPCs, and promote the phosphorylation of AKT and mTOR proteins under high-glucose condition. Investigation of the underlying mechanism revealed that circ-ADAM9, as a miRNA sponges of mir-20a-5p, promoted autophagy and apoptosis of EPCs induced by high-concentration glucose. Circ-ADAM9 upregulated PTEN and ATG7 in interaction with mir-20a-5p, and inhibited the phosphorylation of AKT and mTOR to aggravate autophagy and apoptosis of EPCs under high glucose. In addition, silencing of circ-ADAM9 increased microvessel formation in the hind limbs of diabetic mice. Our findings disclose a novel autophagy/apoptosis-regulatory pathway that is composed of mir-20a-5p, circ-ADAM9, PTEN, and ATG7. Circ-ADAM9 is a potential novel target for regulating the function of diabetic EPCs and angiogenesis.

Maggot excretions/secretions promote diabetic wound angiogenesis via miR18a/19a - TSP-1 axis

AIMS

The impaired angiogenesis is one of the main factors affecting the healing of diabetic foot ulcer (DFU) wounds. Maggot debridement therapy (MDT) promotes granulation tissue growth and angiogenesis during DFU wound healing. Non-coding microRNAs can also promote local angiogenesis in DFU wounds by regulating wound repairing related gene expression. The purpose of this study was to investigate the mechanism of microRNAs in MDT promoting DFU wound angiogenesis.

METHODS

In this study, we applied MDT to treat DFU wound tissue and detect the expression of the miR-17-92 cluster. In vitro experiments, human umbilical vein endothelial cells (HUVECs) were treated with maggot excretions/secretions (ES), the miR-17-92 cluster and the predicted target gene expression were measured. Tube formation assay and cell scratch assay were performed when inhibition of miR-18a/19a or overexpression of thrombospondin-1 (TSP-1) were used in this study.

RESULTS

miR-18a/19a transcription significantly up-regulated and TSP-1 expression down-regulated in patients wound tissue and in HUVECs. Inhibition of miR-18a/19a or overexpression of TSP-1 partially blocked the migration and tube formation ability stimulated by ES.

CONCLUSION

Targeted activation of miR-18a/19a transcription levels and subsequent regulation of TSP-1 expression may be a novel therapeutic strategy for DFU.

Downregulation of CRABP2 Inhibit the Tumorigenesis of Hepatocellular Carcinoma In Vivo and In Vitro

Cellular retinoic acid-binding protein 2 (CRABP2) binds retinoic acid (RA) in the cytoplasm and transports it into the nucleus, allowing for the regulation of specific downstream signal pathway. Abnormal expression of CRABP2 has been detected in the development of several tumors. However, the role of CRABP2 in hepatocellular carcinoma (HCC) has never been revealed. The current study aimed to investigate the role of CRABP2 in HCC and illuminate the potential molecular mechanisms. The expression of CRABP2 in HCC tissues and cell lines was detected by western blotting and immunohistochemistry assays. Our results demonstrated that the expression levels of CRABP2 in HCC tissues were elevated with the tumor stage development, and it was also elevated in HCC cell lines. To evaluate the function of CRABP2, shRNA-knockdown strategy was used in HCC cells. Cell proliferation, metastasis, and apoptosis were analyzed by CCK-8, EdU staining, transwell, and flow cytometry assays, respectively. Based on our results, knockdown of CRABP2 by shRNA resulted in the inhibition of tumor proliferation, migration, and invasion in vitro, followed by increased tumor apoptosis-related protein expression and decreased ERK/VEGF pathway-related proteins expression. CRABP2 silencing in HCC cells also resulted in the failure to develop tumors in vivo. These results provide important insights into the role of CRABP2 in the development and development of HCC. Based on our findings, CRABP2 may be used as a novel diagnostic biomarker, and regulation of CRABP2 in HCC may provide a potential molecular target for the therapy of HCC.

Suppressing miR-21 activity in tumor-associated macrophages promotes an antitumor immune response

microRNA-21 (miR-21) is the most commonly upregulated miRNA in solid tumors. This cancer-associated microRNA (oncomiR) regulates various downstream effectors associated with tumor pathogenesis during all stages of carcinogenesis. In this study, we analyzed the function of miR-21 in noncancer cells of the tumor microenvironment to further evaluate its contribution to tumor progression. We report that the expression of miR-21 in cells of the tumor immune infiltrate, and in particular in macrophages, was responsible for promoting tumor growth. Absence of miR-21 expression in tumor- associated macrophages (TAMs), caused a global rewiring of their transcriptional regulatory network that was skewed toward a proinflammatory angiostatic phenotype. This promoted an antitumoral immune response characterized by a macrophage-mediated improvement of cytotoxic T-cell responses through the induction of cytokines and chemokines, including IL-12 and C-X-C motif chemokine 10. These effects translated to a reduction in tumor neovascularization and an induction of tumor cell death that led to decreased tumor growth. Additionally, using the carrier peptide pH (low) insertion peptide, we were able to target miR-21 in TAMs, which decreased tumor growth even under conditions where miR-21 expression was deficient in cancer cells. Consequently, miR-21 inhibition in TAMs induced an angiostatic and immunostimulatory activation with potential therapeutic implications.

Alternagin-C (ALT-C), a disintegrin-like protein, attenuates alpha2beta1 integrin and VEGF receptor 2 signaling resulting in angiogenesis inhibition

Angiogenesis, a crucial process in tumor progression, is mainly regulated by vascular endothelial growth factor (VEGF) and its receptor, VEGFR2. Studies have shown the interaction between α₂β₁ integrin, a collagen receptor, and VEGFR2 in VEGF-driven angiogenesis in vitro and in vivo. Alternagin-C (ALT-C), an ECD-disintegrin-like protein from Bothrops alternatus snake venom, has high affinity for α₂β₁ integrin and shows antiangiogenic activity in concentrations higher than 100 nM. Despite previous results, its mechanism of action on angiogenic signaling pathways has not been addressed. Here we evaluate the antiangiogenic activity of ALT-C in human umbilical vein endothelial cells (HUVECs) associated or not with VEGF, as well as its interference in the α₂β₁/VEGFR2 crosstalk. ALT-C (1000 nM) affected actin cytoskeleton, decreased the number of cell filopodia, and strongly inhibited HUVEC tube formation, adhesion to type I collagen and cell migration. Down-regulation of α₂β₁/VEGFR2 crosstalk by ALT-C decreased the protein content and phosphorylation of VEGFR2 and β₁ integrin subunit, inhibited ERK 1/2 and PI3K signaling and regulated FAK/Src and paxillin pathways. Furthermore, ALT-C increased the content of the autophagic markers LC3B and Beclin-1 in the presence of VEGF, which is associated with decreased angiogenesis. In conclusion, we suggest that ALT-C, after binding to α₂β₁ integrin, inhibits VEGF/VEGFR2 signaling, which results in impaired angiogenesis. These results demonstrate that ALT-C may be a potential candidate for the development of antiangiogenic therapies for tumor and metastasis treatment and help to understand the complexity and fundamental role of integrin inhibition in the tumor microenvironment.

Role of miR-92a-3p, oxidative stress, and p38MAPK/NF-κB pathway in rats with central venous catheter related thrombosis

BACKGROUND

miR-92a-3p and oxidative stress are reportedly associated with venous thrombosis. However, the role of miR-92a-3p and oxidative stress in catheter-related thrombosis (CRT) remains ambiguous. Herein, we studied the roles of miR-92a-3p, oxidative stress, and p38-mitogen-activated protein kinase/nuclear factor kappa-B (MAPK/NF-κB) pathway in CRT.

METHODS

Forty-five male rats were randomly and equally divided into control, sham operation, and CRT groups. The rats were sacrificed after 10 days. Reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA) levels in the serum were determined by enzyme-linked immunosorbent assay (ELISA). The expression levels of miR-92a-3p, heme oxygenase-1 (HO-1), NF-κB p65, and p38 MAPK in the venous tissues were detected with quantitative polymerase chain reaction (qPCR) and Western blot.

RESULTS

Thrombosis was observed only in the CRT group. Compared with the levels in the control and sham operation groups, ROS and MDA significantly increased in the CRT group, but SOD significantly decreased. qPCR and Western blot results showed that miR-92a-3p, HO-1, p38 MAPK, and NF-κB p65 expression was significantly upregulated in the venous tissues of the CRT group. Moreover, miR-92a-3p was positively correlated with HO-1, which was positively correlated with p38 MAPK and NF-κB p65.

CONCLUSION

miR-92a-3p was correlated with oxidative stress in CRT. miR-92a-3p and oxidative stress contributed to endothelial dysfunction and simultaneously was associated with CRT.

MicroRNA-18a-5p Administration Suppresses Retinal Neovascularization by Targeting FGF1 and HIF1A

Pathologic ocular neovascularization commonly results in visual impairment or even blindness in numerous fundus diseases, including proliferative diabetic retinopathy (PDR), retinopathy of prematurity (ROP), and age-related macular degeneration (AMD). MicroRNAs regulate angiogenesis through modulating target genes and disease progression, making them a new class of targets for drug discovery. In this study, we investigated the potential role of miR-18a-5p in retinal neovascularization using a mouse model of oxygen-induced proliferative retinopathy (OIR). We found that miR-18a-5p was highly expressed in the retina of pups as well as retinal endothelial cells, and was consistently down-regulated during retinal development. On the other hand, miR-18a-5p was increased significantly during pathologic neovascularization in the retinas of OIR mice. Moreover, intravitreal administration of miRNA mimic, agomiR-18a-5p, significantly suppressed retinal neovascularization in OIR models. Accordingly, agomir-18a-5p markedly suppressed human retinal microvascular endothelial cell (HRMEC) function including proliferation, migration, and tube formation ability. Additionally, we demonstrated that miR-18a-5p directly down-regulated known vascular growth factors, fibroblast growth factor 1 (FGF1) and hypoxia-inducible factor 1-alpha (HIF1A), as the target genes. In conclusion, miR-18a-5p may be a useful drug target for pathologic ocular neovascularization.

miR-136-3p targets PTEN to regulate vascularization and bone formation and ameliorates alcohol-induced osteopenia

Alcohol consumption is regarded as one of the leading risk factors for secondary osteopenia. Coupled angiogenesis and osteogenesis via distinct type-H vessels orchestrates subtle biological processes of bone homeostasis. The dysfunction of angiogenesis and osteogenesis contributes to decreased bone mass during the development of osteopenia. Herein, we identified microRNA-136-3p was remarkedly downregulated in the mouse model of alcohol-induced osteopenia. Following the alcohol administration, downregulated microRNA-136-3p significantly suppressed vascularization and osteogenic differentiation in human umbilical vein endothelial cells (HUVECs) and bone mesenchymal stem cells (BMSCs), respectively. Furthermore, microRNA-136-3p could target phosphatase and tensin homolog deleted on chromosome ten (PTEN) in both HUVECs and BMSCs, thus substantially modulating the capacity of vessel formation and osteogenic differentiation. In the mouse model, microRNA-136-3p Agomir ameliorated alcohol-induced osteopenia, with the concomitant restoration of bone mass and type-H vessel formation. For the first time, this study demonstrated the pivotal role of microRNA-136-3p/PTEN axis in regulations of vascularization and bone formation, which might become the potential therapeutic target of alcohol-induced bone loss.

Overview of Crosstalk Between Multiple Factor of Transcytosis in Blood Brain Barrier

Blood brain barrier (BBB) conserves unique regulatory system to maintain barrier tightness while allowing adequate transport between neurovascular units. This mechanism possess a challenge for drug delivery, while abnormality may result in pathogenesis. Communication between vascular and neural system is mediated through paracellular and transcellular (transcytosis) pathway. Transcytosis itself showed dependency with various components, focusing on caveolae-mediated. Among several factors, intense communication between endothelial cells, pericytes, and astrocytes is the key for a normal development. Regulatory signaling pathway such as VEGF, Notch, S1P, PDGFβ, Ang/Tie, and TGF-β showed interaction with the transcytosis steps. Recent discoveries showed exploration of various factors which has been proven to interact with one of the process of transcytosis, either endocytosis, endosomal rearrangement, or exocytosis. As well as providing a hypothetical regulatory pathway between each factors, specifically miRNA, mechanical stress, various cytokines, physicochemical, basement membrane and junctions remodeling, and crosstalk between developmental regulatory pathways. Finally, various hypotheses and probable crosstalk between each factors will be expressed, to point out relevant research application (Drug therapy design and BBB-on-a-chip) and unexplored terrain.

MicroRNAs in Vascular Eye Diseases

Since the discovery of the first microRNA (miRNA) decades ago, studies of miRNA biology have expanded in many biomedical research fields, including eye research. The critical roles of miRNAs in normal development and diseases have made miRNAs useful biomarkers or molecular targets for potential therapeutics. In the eye, ocular neovascularization (NV) is a leading cause of blindness in multiple vascular eye diseases. Current anti-angiogenic therapies, such as anti-vascular endothelial growth factor (VEGF) treatment, have their limitations, indicating the need for investigating new targets. Recent studies established the roles of various miRNAs in the regulation of pathological ocular NV, suggesting miRNAs as both biomarkers and therapeutic targets in vascular eye diseases. This review summarizes the biogenesis of miRNAs, and their functions in the normal development and diseases of the eye, with a focus on clinical and experimental retinopathies in both human and animal models. Discovery of novel targets involving miRNAs in vascular eye diseases will provide insights for developing new treatments to counter ocular NV.

Nucleophosmin contributes to vascular inflammation and endothelial dysfunction in atherosclerosis progression

OBJECTIVE

It is unclear whether nucleophosmin (NPM) participates in cardiovascular disease. The present study aimed to investigate the role and underlying mechanisms of NPM in atherosclerosis.

METHODS

Levels and location of NPM in human carotid atherosclerotic plaques and healthy controls were detected by real-time polymerase chain reaction, immunoblots, and immunofluorescence. Atherosclerotic prone ApoE^-/- mice were fed with a Western diet for 16 weeks as an in vivo model. Human primary umbilical vein endothelial cells (HUVECs) were cultured as an in vitro model.

RESULTS

Compared with controls, we found that NPM levels in human carotid atherosclerotic plaques were more than twice as high as in normal arteries, which mainly localized in endothelial cells. In vivo, adenovirus-containing NPM small hairpin RNA attenuated atherosclerotic lesion and promoted plaque stabilization in ApoE^-/- mice fed a Western diet by reducing vascular inflammation, maintaining endothelial function, and decreasing macrophage infiltration. Furthermore, NPM knockdown decreased nuclear factor-κB (NF-κB) p65 phosphorylation. In cultured HUVECs, palmitic acid increased the protein levels of NPM and induced the expression of inflammatory cytokines and monocyte adhesion, whereas NPM knockdown attenuated this effect. In HUVECs, NPM protein physically interacted with NF-κB p65 subunit and promoted its nuclear transposition. NPM also increased the transcriptional activity of NF-κB p65 promoter and enhance its binding to target genes, including interleukin-1β, interleukin-6, intercellular adhesion molecule-1, and E-selectin.

CONCLUSIONS

These data provide novel evidence that NPM promotes atherosclerosis by inducing vascular inflammation and endothelial dysfunction through the NF-κB signaling pathway and suggest that NPM may be a promising target for atherosclerosis prevention and treatment.

Insights into the Regulation of Tumor Angiogenesis by Micro-RNAs

One of the hallmarks of cancer is angiogenesis, a series of events leading to the formation of the abnormal vascular network required for tumor growth, development, progression, and metastasis. MicroRNAs (miRNAs) are short, single-stranded, non-coding RNAs whose functions include modulation of the expression of pro- and anti-angiogenic factors and regulation of the function of vascular endothelial cells. Vascular-associated microRNAs can be either pro- or anti-angiogenic. In cancer, miRNA expression levels are deregulated and typically vary during tumor progression. Experimental data indicate that the tumor phenotype can be modified by targeting miRNA expression. Based on these observations, miRNAs may be promising targets for the development of novel anti-angiogenic therapies. This review discusses the role of various miRNAs and their targets in tumor angiogenesis, describes the strategies and challenges of miRNA-based anti-angiogenic therapies and explores the potential use of miRNAs as biomarkers for anti-angiogenic therapy response.

The role of endothelial miRNAs in myocardial biology and disease

The myocardium is a highly structured pluricellular tissue which is governed by an intricate network of intercellular communication. Endothelial cells are the most abundant cell type in the myocardium and exert crucial roles in both healthy myocardium and during myocardial disease. In the last decade, microRNAs have emerged as new actors in the regulation of cellular function in almost every cell type. Here, we review recent evidence on the regulatory function of different microRNAs expressed in endothelial cells, also called endothelial microRNAs, in healthy and diseased myocardium. Endothelial microRNA emerged as modulators of angiogenesis in the myocardium, they are implicated in the paracrine role of endothelial cells in regulating cardiac contractility and homeostasis, and interfere in the crosstalk between endothelial cells and cardiomyocytes.

Associations of microRNAs, Angiogenesis-Regulating Factors and CFH Y402H Polymorphism-An Attempt to Search for Systemic Biomarkers in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) remains the leading cause of blindness in elderly people, but the pathophysiology of this disease is still largely unknown. We investigated the systemic expression of angiogenesis-regulating growth factors and selected miRNAs known to regulate angiogenesis in AMD patients. We also focused on possible correlations of their expression with the presence of CFH Y402H or ARMS A69S risk variants. A total of 354 AMD patients and 121 controls were enrolled in this study. The levels of angiogenesis-regulating factors were analyzed in plasma samples using Luminex technology. The expression of selected miRNAs was analyzed in peripheral blood plasma using real-time qPCR. The genetic analysis was performed with an Illumina NextSeq500 system. AMD was an independent factor associated with lower levels of angiogenin (β = −0.29, p < 0.001), endostatin (β = −0.18, p < 0.001), FGF-basic (β = −0.18, p < 0.001), PlGF (β = −0.24, p < 0.001), miRNA-21-3p (β = −0.13, p = 0.01) and miRNA-155-5p (β = −0.16, p = 0.002); and with higher levels of FGF-acidic (β = 0.11, p = 0.03), miRNA-23a-3p (β = 0.17, p < 0.001), miRNA-126-5p (β = 0.13, p = 0.009), miRNA-16-5p (β = 0.40, p < 0.001), miRNA-17-3p (β = 0.13, p = 0.01), miRNA-17-5p (β = 0.17, p < 0.001), miRNA-223-3p (β = 0.15, p = 0.004), and miRNA-93 (β = 0.11, p = 0.04). The expression of analyzed miRNA molecules significantly correlated with the levels of tested angiogenesis-regulating factors and clinical parameters in AMD patients, whereas such correlations were not observed in controls. We also found an association between the CFH Y402H polymorphism and miRNA profiles, whereby TT homozygotes showed evidently higher expression of miRNA-16-5p than CC homozygotes or TC heterozygotes (p = 0.0007). Our results suggest that the balance between systemic pro- and anti-angiogenic factors and miRNAs is vital in multifactorial AMD pathogenesis.

Colorectal cancer cells differentially impact migration and microRNA expression in endothelial cells

Angiogenesis is an essential step in cancer progression and metastasis. Changes in the microRNA (miRNA or miR) expression profiles of endothelial cells (ECs) elicited by cancer cells promote angiogenesis. Vascular endothelial growth factor (VEGF), a key pro-angiogenic factor, influences miRNA expression in ECs; however, the exact role that VEGF serves in miRNA regulation during angiogenesis is poorly defined. The present study aimed to demonstrate the differential angiogenic effects on human umbilical vein endothelial cells (HUVECs) of five different colorectal cancer (CRC) cell lines by in vitro HUVEC migration and angiogenesis assays in response to CRC-conditioned medium (CM). Among the tested CMs, LoVo was the most effective cell line in eliciting HUVEC angiogenic phenotypes, at least partially due to its high VEGF level. It was also observed that pro-angiogenesis-regulatory miRNAs (angio-miRNA) miR-296, miR-132, miR-105 and miR-200 were upregulated in the VEGF-rich LoVo CM compared with the VEGF-scarce SW620 CM. In addition, treatment with VEGF receptor 2 inhibitor downregulated the pro-angio-miRNAs, with the exception of miR-132, suggesting that VEGF, as well as additional signaling, is required for angio-miRNA expression. Quantitative analyses on pro-angio-miRNA target expression suggested that independent pathways may be involved in the regulation of their expression. Overall, the data from the present study indicated that multiple paracrine factors, including VEGF secreted by CRCs, effectively modulated angio-miRNA expression, thus impacting their target expression and the angiogenic phenotypes of HUVECs.

miR17~92 restrains pro-apoptotic BIM to ensure survival of haematopoietic stem and progenitor cells

The miR17~92 cluster plays important roles in haematopoiesis. However, it is not clear at what stage of differentiation and through which targets miR17~92 exerts this function. Therefore, we generated miR17~92^fl/fl; RosaCreERT2 mice for inducible deletion of miR17~92 in haematopoietic cells. Bone marrow reconstitution experiments revealed that miR17~92-deleted cells were not capable to contribute to mature haematopoietic lineages, which was due to defects in haematopoietic stem/progenitor cells (HSPCs). To identify the critical factor targeted by miR17~92 we performed gene expression analysis in HSPCs, demonstrating that mRNA levels of pro-apoptotic Bim inversely correlated with the expression of the miR17~92 cluster. Strikingly, loss of pro-apoptotic BIM completely prevented the loss of HSPCs caused by deletion of miR17~92. The BIM/miR17~92 interaction is conserved in human CD34⁺ HSPCs, as miR17~92 inhibition or blockade of its binding to the BIM 3'UTR reduced the survival and growth of these cells. Despite the prediction that miR17~92 functions by impacting a plethora of different targets, the absence of BIM alone is sufficient to prevent all defects caused by deletion of miR17~92 in haematopoietic cells.

Irisin exerts a therapeutic effect against myocardial infarction via promoting angiogenesis

Irisin, a myokine, is cleaved from the extracellular portion of fibronectin domain-containing 5 protein in skeletal muscle and myocardium and secreted into circulation as a hormone during exercise. Irisin has been found to exert protective effects against lung and heart injuries. However, whether irisin influences myocardial infarction (MI) remains unclear. In this study we investigated the therapeutic effects of irisin in an acute MI model and its underlying mechanisms. Adult C57BL/6 mice were subjected to ligation of the left anterior descending coronary artery and treated with irisin for 2 weeks after MI. Cardiac function was assessed using echocardiography. We found that irisin administration significantly alleviated MI-induced cardiac dysfunction and ventricular dilation at 4 weeks post-MI. Irisin significantly reduced infarct size and fibrosis in post-MI hearts. Irisin administration significantly increased angiogenesis in the infarct border zone and decreased cardiomyocyte apoptosis, but did not influence cardiomyocyte proliferation. In human umbilical vein endothelial cells (HUVEC), irisin significantly increased the phosphorylation of ERK, and promoted the migration of HUVEC detected in wound-healing and transwell chamber migration assay. The effects of irisin were blocked by the ERK inhibitor U0126. In conclusion, irisin improves cardiac function and reduces infarct size in post-MI mouse heart. The therapeutic effect is associated with its pro-angiogenic function through activating ERK signaling pathway.

BDNF (Brain-Derived Neurotrophic Factor) Promotes Embryonic Stem Cells Differentiation to Endothelial Cells Via a Molecular Pathway, Including MicroRNA-214, EZH2 (Enhancer of Zeste Homolog 2), and eNOS (Endothelial Nitric Oxide Synthase)

Objective- The NTs (neurotrophins), BDNF (brain-derived neurotrophic factor) and NT-3 promote vascular development and angiogenesis. This study investigated the contribution of endogenous NTs in embryonic stem cell (ESC) vascular differentiation and the potential of exogenous BDNF to improve the process of ESC differentiation to endothelial cells (ECs). Approach and Results- Mouse ESCs were differentiated into vascular cells using a 2-dimensional embryoid body (EB) model. Supplementation of either BDNF or NT-3 increased EC progenitors' abundance at day 7 and enlarged the peripheral vascular plexus with ECs and SM22α⁺ (smooth muscle 22 alpha-positive) smooth muscle cells by day 13. Conversely, inhibition of either BDNF or NT-3 receptor signaling reduced ECs, without affecting smooth muscle cells spread. This suggests that during vascular development, endogenous NTs are especially relevant for endothelial differentiation. At mechanistic level, we have identified that BDNF-driven ESC-endothelial differentiation is mediated by a pathway encompassing the transcriptional repressor EZH2 (enhancer of zeste homolog 2), microRNA-214 (miR-214), and eNOS (endothelial nitric oxide synthase). It was known that eNOS, which is needed for endothelial differentiation, can be transcriptionally repressed by EZH2. In turn, miR-214 targets EZH2 for inhibition. We newly found that in ESC-ECs, BDNF increases miR-214 expression, reduces EZH2 occupancy of the eNOS promoter, and increases eNOS expression. Moreover, we found that NRP-1 (neuropilin 1), KDR (kinase insert domain receptor), and pCas¹³⁰ (p130 Crk-associated substrate kinase), which reportedly induce definitive endothelial differentiation of pluripotent cells, were increased in BDNF-conditioned ESC-EC. Mechanistically, miR-214 mediated the BDNF-induced expressional changes, contributing to BDNF-driven endothelial differentiation. Finally, BDNF-conditioned ESC-ECs promoted angiogenesis in vitro and in vivo. Conclusions- BDNF promotes ESC-endothelial differentiation acting via miR-214.

Combination of Epigallocatechin-3-gallate and Silibinin: A Novel Approach for Targeting Both Tumor and Endothelial Cells

Despite promising benefits, anti-angiogenic strategies have revealed several drawbacks, which necessitate development of novel approaches in cancer therapy strategies including non-small-cell lung cancer, as one of the leading causes of cancer death, all over the world. Combination of flavonoids could be a safe and effective option to synergize their impact on mechanisms controlling tumor angiogenesis. In this study, we have investigated the plausible synergism of epigallocatechin-3-gallate (EGCG) and silibinin on endothelial cells, for the first time. Cell viability and migration were evaluated by survival and wound healing assays, respectively. Then, we assessed the expression of VEGF, VEGFR2, and miR-17-92 cluster using real-time polymerase chain reaction in endothelial-tumor cell and endothelial-fibroblast coculture models. EGCG ± silibinin suppressed endothelial and lung tumor cell migration in lower than 50% toxic doses. VEGF, VEGFR2, and pro-angiogenic members of the miR-17-92 cluster were downregulated upon treatments. Specifically, the combination treatment upregulated an anti-angiogenic member of the cluster, miR-19b. Our data provides evidence to utilize the EGCG and silibinin combination as a novel approach to target tumor angiogenesis in the future.

gga-miR-146c Activates TLR6/MyD88/NF-κB Pathway through Targeting MMP16 to Prevent Mycoplasma Gallisepticum (HS Strain) Infection in Chickens

Mycoplasma gallisepticum (MG), a pathogen that infects chickens and some other birds, triggers chronic respiratory disease (CRD) in chickens, which is characterized by inflammation. The investigation of microbial pathogenesis would contribute to the deep understanding of infection control. Since microribonucleic acids (miRNAs) play a key role in this process, gga-mir-146c, an upregulated miRNA upon MG infection, was selected according to our previous RNA-sequencing data. In this paper, we predicted and validated that MMP16 is one of gga-miR-146c target genes. Results show that MMP16 is the target of gga-miR-146c and gga-miR-146c can downregulate MMP16 expression within limits. gga-miR-146c upregulation significantly increased the expression of TLR6, NF-κB p65, MyD88, and TNF-α, whereas the gga-miR-146c inhibitor led to an opposite result. gga-miR-146c upregulation effectively decreased apoptosis and stimulated DF-1 cells proliferation upon MG infection. On the contrary, gga-miR-146c inhibitor promoted apoptosis and repressed the proliferation. Collectively, our results suggest that gga-miR-146c upregulation upon MG infection represses MMP16 expression, activating TLR6/MyD88/NF-κB pathway, promoting cell proliferation by inhibiting cell apoptosis, and, finally, enhancing cell cycle progression to defend against host MG infection.

Glioma stem cells-derived exosomal miR-26a promotes angiogenesis of microvessel endothelial cells in glioma

BACKGROUND

Cancer stem cells (CSCs), which are involved in cancer initiation and metastasis, could potentially release exosomes that mediate cellular communication by delivering microRNAs (miRNAs). Based on the role of miR-26a in angiogenesis of glioma, our study was performed to investigate whether glioma stem cells (GSCs)-derived exosomes containing miR-26a could exert effects on angiogenesis of microvessel endothelial cells in glioma, in order to provide a new therapeutic RNA vehicle for glioma therapies.

METHODS

The expression of miR-26a and PTEN in glioma was quantified and the interaction among miR-26a, PTEN and PI3K/Akt signaling pathway was examined. Next, a series of gain- and loss-of function experiments were conducted to determine the role of miR-26a in angiogenesis of human brain microvascular endothelial cells (HBMECs). Subsequently, HBMECs were exposed to exosomes derived from GSCs with the gain-/loss-of-function of miR-26a. Finally, the effect of exosomal miR-26a on angiogenesis of HBMECs was assessed both in vitro and in vivo.

RESULTS

The results revealed that PTEN was down-regulated, while miR-26a was up-regulated in glioma. miR-26a activated the PI3K/Akt signaling pathway by targeting PTEN. Restored miR-26a promoted proliferation, migration, tube formation, and angiogenesis of HBMECs in vitro. In addition, GSCs-derived exosomes overexpressing miR-26a contributed to enhanced proliferation and angiogenesis of HBMECs in vitro through inhibition of PTEN. The angiogenic effects of GSCs-derived exosomes overexpressing miR-26a in vivo were consistent with the above-mentioned in vitro findings.

CONCLUSION

Collectively, our study demonstrates that GSCs-derived exosomal miR-26a promotes angiogenesis of HBMECs, highlighting an angiogenic role of miR-26a via exosomes.

Construction of Pedicled Smooth Muscle Tissues by Combining the Capsule Tissue and Cell Sheet Engineering

The survival of engineered tissue requires the formation of its own capillary network, which can anastomose with the host vasculature after transplantation. Currently, while many strategies, such as modifying the scaffold material, adding endothelial cells, or angiogenic factors, have been researched, engineered tissue implanted in vivo cannot timely access to sufficient blood supply, leading to ischemic apoptosis or shrinkage. Constructing vascularized engineered tissue with its own axial vessels and subsequent pedicled transfer is promising to solve the problem of vascularization in tissue engineering. In this study, we used the tissue expander capsule as a novel platform for vascularizing autologous smooth muscle cell (SMC) sheets and fabricating vascularized engineered tissue with its own vascular pedicle. First, we verified which time point was the most effective for constructing an axial capsule vascular bed. Second, we compared the outcome of SMC sheet transplantation onto the expander capsule and classical dorsal subcutaneous tissue, which was widely used in other studies for vascularization. Finally, we transplanted multilayered SMC sheets onto the capsule bed twice to verify the feasibility of fabricating thick pedicled engineered smooth muscle tissues. The results indicated that the axial capsule tissue could be successfully induced, and the capsule tissue 1 week after full expansion was the most vascularized. Quantitative comparisons of thickness, vessel density, and apoptosis of cell sheet grafts onto two vascular beds proved that the axial capsule vascular bed was more favorable to the growth and vascularization of transplants than classical subcutaneous tissue. Furthermore, thick vascularized smooth muscle tissues with the vascular pedicle could be constructed by multi-transplanting cell sheets onto the capsule bed. The combination of axial capsule vascular bed and cell sheet engineering may provide an efficient strategy to overcome the problem of slow or insufficient vascularization in tissue engineering.

MicroRNAs in endothelial cell homeostasis and vascular disease

PURPOSE OF REVIEW

Since the first discovery of microRNAs (miRNAs) in 1993, the involvement of miRNAs in different aspects of vascular disease has emerged as an important research field. In this review, we summarize the fundamental roles of miRNAs in controlling endothelial cell functions and their implication with several aspects of vascular dysfunction.

RECENT FINDINGS

MiRNAs have been found to be critical modulators of endothelial homeostasis. The dysregulation of miRNAs has been linked to endothelial dysfunction and the development and progression of vascular disease which and open new opportunities of using miRNAs as potential therapeutic targets for vascular disease.

SUMMARY

Further determination of miRNA regulatory circuits and defining miRNAs-specific target genes remains key to future miRNA-based therapeutic applications toward vascular disease prevention. Many new and unanticipated roles of miRNAs in the control of endothelial functions will assist clinicians and researchers in developing potential therapeutic applications.

Mechanism of piR-DQ590027/MIR17HG regulating the permeability of glioma conditioned normal BBB

Background

The blood-brain barrier (BBB) strongly restricts the entry of anti-glioma drugs into tumor tissues and thus decreases chemotherapy efficacy. Malignant gliomas are highly invasive tumours that use the perivascular space for invasion and co-opt existing vessels as satellite tumor form. Because regulation of the effect of noncoding RNA on BBB function is attracting growing attention, we investigated the effects of noncoding RNA on the permeability of glioma conditioned normal BBB and the mechanism involved using PIWI-associated RNA piR-DQ590027 as a starting point.

Methods

The mRNA levels of MIR17HG, miR-153, miR-377, ZO-1, occludin, and claudin-5 were determined using real-time PCR. Transient cell transfection was performed using Lipofectamine 3000 reagent. TEER and HRP flux were applied to measure the permeability of glioma conditioned normal BBB. Western blotting and immunofluorescence assays were used to measure ZO-1, occludin, and claudin-5 levels. Reporter vector construction and a luciferase reporter assay were performed to detect the binding sites of MIR17HG and piR-DQ590027, MIR17HG and miR-153 (miR-377), and FOXR2 and miR-153 (miR-377). RNA immunoprecipitation was used to test the interaction between miR-153 (miR-377) and its target proteins. Chromatin immunoprecipitation was performed to detect the interaction between the transcription factor FOXR2 and ZO-1, occludin, and claudin-5.

Results

piR-DQ590027 was expressed at low levels in glioma-conditioned ECs (GECs) of the in vitro glioma conditioned normal BBB model. Overexpression of piR-DQ590027 down-regulated the expressions of ZO-1, occludin, and claudin-5 and increased the permeability of glioma conditioned normal BBB. MIR17HG had high expression in GECs but miR-153 and miR-377 had low expression. piR-DQ590027 bound to and negatively regulated MIR17HG. FOXR2 was a downstream target of miR-153 and miR-377; MIR17HG bound separately to miR-153 and miR-377 and negatively regulated their ability to mediate FOXR2 expression. FOXR2 associated with the promoter regions of ZO-1, occludin, and claudin-5 in GECs to promote their transcription.

Conclusion

The piR-DQ590027/MIR17HG/miR-153 (miR-377)/FOXR2 pathway plays an important role in regulating glioma conditioned normal BBB permeability and provides a new target for the comprehensive treatment of glioma.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0886-0) contains supplementary material, which is available to authorized users.

MicroRNAs Regulating Reactive Oxygen Species in Cardiovascular Diseases

SIGNIFICANCE

Oxidative stress caused by overproduction of reactive oxygen species (ROS) in cells is one of the most important contributors to the pathogenesis of cardiovascular and metabolic diseases such as hypertension and atherosclerosis. Excessive accumulation of ROS impairs, while limiting oxidative stress protects cardiovascular and metabolic function through various cellular mechanisms. Recent Advances: MicroRNAs (miRNAs) are novel regulators of oxidative stress in cardiovascular cells that modulate the expression of redox-related genes. This article summarizes recent advances in our understanding of how miRNAs target major ROS generators, antioxidant signaling pathways, and effectors in cells of the cardiovascular system.

CRITICAL ISSUES

The role of miRNAs in regulating ROS in cardiovascular cells is complicated because miRNAs can target multiple redox-related genes, act on redox regulatory pathways indirectly, and display context-dependent pro- or antioxidant effects. The complex regulatory network of ROS and the plethora of targets make it difficult to pin point the role of miRNAs and develop them as therapeutics. Therefore, these properties should be considered when designing strategies for therapeutic or diagnostic development.

FUTURE DIRECTIONS

Future studies can gain a better understanding of redox-related miRNAs by investigating their own regulatory mechanisms and the dual role of ROS in the cardiovascular systems. The combination of improved study design and technical advancements will reveal newer pathophysiological importance of redox-related miRNAs.

The regulatory role of microRNAs in angiogenesis-related diseases

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at a post-transcriptional level via either the degradation or translational repression of a target mRNA. They play an irreplaceable role in angiogenesis by regulating the proliferation, differentiation, apoptosis, migration and tube formation of angiogenesis-related cells, which are indispensable for multitudinous physiological and pathological processes, especially for the occurrence and development of vascular diseases. Imbalance between the regulation of miRNAs and angiogenesis may cause many diseases such as cancer, cardiovascular disease, aneurysm, Kawasaki disease, aortic dissection, phlebothrombosis and diabetic microvascular complication. Therefore, it is important to explore the essential role of miRNAs in angiogenesis, which might help to uncover new and effective therapeutic strategies for vascular diseases. This review focuses on the interactions between miRNAs and angiogenesis, and miRNA-based biomarkers in the diagnosis, treatment and prognosis of angiogenesis-related diseases, providing an update on the understanding of the clinical value of miRNAs in targeting angiogenesis.

Phenotypic miRNA Screen Identifies miR-26b to Promote the Growth and Survival of Endothelial Cells

Endothelial cell (EC) proliferation is a crucial event in physiological and pathological angiogenesis. MicroRNAs (miRNAs) have emerged as important modulators of the angiogenic switch. Here we conducted high-content screening of a human miRNA mimic library to identify novel regulators of EC growth systematically. Several miRNAs were nominated that enhanced or inhibited EC growth. Of these, we focused on miR-26b, which is a conserved candidate and expressed in multiple human EC types. miR-26b overexpression enhanced EC proliferation, migration, and tube formation, while inhibition of miR-26b suppressed the proliferative and angiogenic capacity of ECs. A combinatory functional small interfering RNA (siRNA) screening of 48 predicted gene targets revealed that miR-26b enhanced EC growth and survival through inhibiting PTEN expression. Local administration of miR-26b mimics promoted the growth of new microvessels in the Matrigel plug model. In the mouse model of hindlimb ischemia, miR-26b was found to be downregulated in endothelium in the first week following ischemia, and local overexpression of miR-26b improved the survival of capillaries and muscle fibers in ischemic muscles. Our findings suggest that miR-26b enhances EC proliferation, survival, and angiogenesis. miR-26b is a potential target for developing novel pro-angiogenic therapeutics in ischemic disease.

miR-17-92 cluster is connected with disease progression and oxaliplatin/capecitabine chemotherapy efficacy in advanced gastric cancer patients: A preliminary study

This study aimed to determine the role of plasma miR-17-92 cluster level in predicting chemoresistance in patients with gastric cancer (GC) undergoing oxaliplatin/capecitabine (XELOX) chemotherapy.Patients recently diagnosed with advanced GC were chosen as participants based on the inclusion criteria. The plasma levels of miR-17-5p, miR-18a, miR-19a/b, miR-20a, and miR-92-1 (miR-17-92 cluster) were determined through quantitative RT-PCR of blood samples from GC patients and healthy volunteers. All the patients received XELOX chemotherapy, and the effectiveness of the chemotherapy was evaluated.The miR-17-92 plasma level was increased in advanced GC patients and decreased after XELOX chemotherapy. Moreover, the miR-17-92 cluster level was associated with chemotherapy response but not with chemotherapy-related toxicity. The miR-17-92 cluster plasma level was decreased in chemosensitive patients, but not in chemoresistant patients, after chemotherapy. The sensitivity and specificity of the combined detection of the miR-17-92 cluster in patients with advanced GC were 100% each.The results suggest that the miR-17-92 plasma level is associated with the progression of advanced GC and effectiveness of XELOX chemotherapy.

Non-coding RNAs in cardiovascular diseases: diagnostic and therapeutic perspectives

Recent research has demonstrated that the non-coding genome plays a key role in genetic programming and gene regulation during development as well as in health and cardiovascular disease. About 99% of the human genome do not encode proteins, but are transcriptionally active representing a broad spectrum of non-coding RNAs (ncRNAs) with important regulatory and structural functions. Non-coding RNAs have been identified as critical novel regulators of cardiovascular risk factors and cell functions and are thus important candidates to improve diagnostics and prognosis assessment. Beyond this, ncRNAs are rapidly emgerging as fundamentally novel therapeutics. On a first level, ncRNAs provide novel therapeutic targets some of which are entering assessment in clinical trials. On a second level, new therapeutic tools were developed from endogenous ncRNAs serving as blueprints. Particularly advanced is the development of RNA interference (RNAi) drugs which use recently discovered pathways of endogenous short interfering RNAs and are becoming versatile tools for efficient silencing of protein expression. Pioneering clinical studies include RNAi drugs targeting liver synthesis of PCSK9 resulting in highly significant lowering of LDL cholesterol or targeting liver transthyretin (TTR) synthesis for treatment of cardiac TTR amyloidosis. Further novel drugs mimicking actions of endogenous ncRNAs may arise from exploitation of molecular interactions not accessible to conventional pharmacology. We provide an update on recent developments and perspectives for diagnostic and therapeutic use of ncRNAs in cardiovascular diseases, including atherosclerosis/coronary disease, post-myocardial infarction remodelling, and heart failure.

Role of endothelial microRNA-23 clusters in angiogenesis in vivo

The capillary network is distributed throughout the body, and its reconstruction is induced under various pathophysiological conditions. MicroRNAs are small noncoding RNAs that regulate gene expression via posttranscriptional mechanisms and are involved in many biological functions, including angiogenesis. Previous studies have shown that each microRNA of miR-23 clusters, composed of the miR-23a cluster (miR-23a~27a~24-2) and miR-23b cluster (miR-23b~27b~24-1), regulates angiogenesis in vitro. However, the role of miR-23 clusters, located within a single transcription unit, in angiogenesis in vivo has not been elucidated. In the present study, we generated vascular endothelial cell (EC)-specific miR-23 cluster double-knockout (DKO) mice and demonstrated sprouting angiogenesis under various conditions, including voluntary running exercise, hindlimb ischemia, skin wound healing, and EC sprouting from aorta explants. Here, we demonstrated that EC-specific miR-23 DKO mice are viable and fertile, with no gross abnormalities observed in pups or adults. The capillary number was normally increased in the muscles of these DKO mice in response to 2 wk of voluntary running and hindlimb ischemia. Furthermore, we did not observe any abnormalities in skin wound closure or EC sprouting from aortic ring explants in EC-specific miR-23 cluster DKO mice. Our results suggest that endothelial miR-23 clusters are dispensable for embryonic development and postnatal angiogenesis in vivo. NEW & NOTEWORTHY We generated vascular endothelial cell (EC)-specific miR-23a/b cluster double-knockout mice and determined sprouting angiogenesis under various conditions, including voluntary running exercise, hindlimb ischemia, skin wound healing, and EC sprouting from aorta explants. We demonstrated that the double-knockout mice were viable and fertile, with no gross abnormalities in exercise- and ischemia-induced angiogenesis and skin wound closure or EC sprouting from aortic ring explants.

Macrophage deficiency of miR-21 promotes apoptosis, plaque necrosis, and vascular inflammation during atherogenesis

Atherosclerosis, the major cause of cardiovascular disease, is a chronic inflammatory disease characterized by the accumulation of lipids and inflammatory cells in the artery wall. Aberrant expression of microRNAs has been implicated in the pathophysiological processes underlying the progression of atherosclerosis. Here, we define the contribution of miR‐21 in hematopoietic cells during atherogenesis. Interestingly, we found that miR‐21 is the most abundant miRNA in macrophages and its absence results in accelerated atherosclerosis, plaque necrosis, and vascular inflammation. miR‐21 expression influences foam cell formation, sensitivity to ER‐stress‐induced apoptosis, and phagocytic clearance capacity. Mechanistically, we discovered that the absence of miR‐21 in macrophages increases the expression of the miR‐21 target gene, MKK3, promoting the induction of p38‐CHOP and JNK signaling. Both pathways enhance macrophage apoptosis and promote the post‐translational degradation of ABCG1, a transporter that regulates cholesterol efflux in macrophages. Altogether, these findings reveal a major role for hematopoietic miR‐21 in atherogenesis.

Post-transcriptional Modulation of Sphingosine-1-Phosphate Receptor 1 by miR-19a Affects Cardiovascular Development in Zebrafish

Sphingosine-1-phosphate is a bioactive lipid and a signaling molecule integrated into many physiological systems such as differentiation, proliferation and migration. In mammals S1P acts through binding to a family of five trans-membrane, G-protein coupled receptors (S1PRs) whose complex role has not been completely elucidated. In this study we use zebrafish, in which seven s1prs have been identified, to investigate the role of s1pr1. In mammals S1PR1 is the most highly expressed S1P receptor in the developing heart and regulates vascular development, but in zebrafish the data concerning its role are contradictory. Here we show that overexpression of zebrafish s1pr1 affects both vascular and cardiac development. Moreover we demonstrate that s1pr1 expression is strongly repressed by miR-19a during the early phases of zebrafish development. In line with this observation and with a recent study showing that miR-19a is downregulated in a zebrafish Holt-Oram model, we now demonstrate that s1pr1 is upregulated in heartstring hearts. Next we investigated whether defects induced by s1pr1 upregulation might contribute to the morphological alterations caused by Tbx5 depletion. We show that downregulation of s1pr1 is able to partially rescue cardiac and fin defects induced by Tbx5 depletion. Taken together, these data support a role for s1pr1 in zebrafish cardiovascular development, suggest the involvement of this receptor in the Tbx5 regulatory circuitry, and further support the crucial role of microRNAs in early phase of zebrafish development.

Angiogenic role of miR-20a in breast cancer

Background

Angiogenesis is a key process for tumor progression and a target for treatment. However, the regulation of breast cancer angiogenesis and its relevance for clinical resistance to antiangiogenic drugs is still incompletely understood. Recent developments on the contribution of microRNA to tumor angiogenesis and on the oncogenic effects of miR-17-92, a miRNA cluster, point to their potential role on breast cancer angiogenesis. The aim of this work was to establish the contribution of miR-20a, a member of miR-17-92 cluster, to tumor angiogenesis in patients with invasive breast carcinoma.

Methods

Tube-formation in vitro assays with conditioned medium from MCF7 and MDA-MB-231 breast cancer cell lines were performed after transfection with miR-20a and anti-miR20a. For clinical validation of the experimental findings, we performed a retrospective analysis of a series of consecutive breast cancer patients (n = 108) treated with neoadjuvant chemotherapy and with a full characterization of their vessel pattern and expression of angiogenic markers in pre-treatment biopsies. Expression of members of the cluster miR-17-92 and of angiogenic markers was determined by RT-qPCR after RNA purification from FFPE samples.

Results

In vitro angiogenesis assays with endothelial cells and conditioned media from breast cancer cell lines showed that transfection with anti-miR20a in MDA-MB-231 significantly decreased mean mesh size and total mesh area, while transfection with miR-20a in MCF7 cells increased mean mesh size. MiR-20a angiogenic effects were abrogated by treatment with aflibercept, a VEGF trap. These results were supported by clinical data showing that mir-20a expression was higher in tumors with no estrogen receptor or with more extensive nodal involvement (cN2-3). A higher miR-20a expression was associated with higher mean vessel size (p = 0.015) and with an angiogenic pattern consisting in larger vessels, higher VEGFA expression and presence of glomeruloid microvascular proliferations (p<0.001). This association was independent of tumor subtype and VEGFA expression.

Conclusions

Transfection of breast cancer cells with miR-20a induces vascular changes in endothelial tube-formation assays. Expression of miR-20a in breast invasive carcinomas is associated with a distinctive angiogenic pattern consisting in large vessels, anomalous glomeruloid microvascular proliferations and high VEGFA expression. Our results suggest a role for miR-20a in the regulation of breast cancer angiogenesis, and raise the possibility of its use as an angiogenic biomarker.

MicroRNA-181a promotes angiogenesis in colorectal cancer by targeting SRCIN1 to promote the SRC/VEGF signaling pathway

Colorectal cancer (CRC) is a very common metastatic tumor with active angiogenesis that requires active angiogenesis. Recently, increased microRNA-181a-5p (miR-181a) expression was found to be significantly associated with liver metastasis and poor outcome in CRC patients. In this study, the role of miR-181a in tumor angiogenesis was further investigated. Capillary tube formation assays were used to demonstrate the ability of miR-181a to promote tumor angiogenesis. Bioinformatics analyses identified SRC kinase signaling inhibitor 1 (SRCIN1) as a potential target of miR-181a. Next, two CRC cell lines (HT29 and SW480) were used to clarify the function of miR-181a through SRCIN1 targeting. In addition, the biological effects of SRCIN1 inhibition by miR-181a were examined in vitro by quantitative RT-PCR, western blotting and enzyme-linked immunosorbent assay and in vivo by Matrigel plug angiogenesis assays and immunohistochemical staining. In clinical samples, Fluorescence in situ hybridization and immunofluorescence were performed to detect the relation between miR-181a and SRCIN1. In addition, SRCIN1 protein and miR-181a expression levels in CRC tissues were also measured by western blot and quantitative real-time polymerase chain reaction. MiR-181a markedly augmented the capability of CRC cells to advance tube formation in endothelial cells in vitro. The Matrigel plug assay showed that miR-181a promoted angiogenesis in vivo. In conclusion, miR-181a inhibited SRCIN1, which caused SRC to transform from an inactive status to an active conformation and to trigger vascular endothelial growth factor secretion, leading to increased angiogenesis. MiR-181a dysregulation contributes to angiogenesis in CRC, and downregulation of miR-181a represents a promising, novel strategy to achieve an efficient antiangiogenic response in anti-CRC therapy.

Inhibition of hsa-miR-6086 protects human umbilical vein endothelial cells against TNFα-induced proliferation inhibition and apoptosis via CDH5

MiRNAs are considered as a novel class of biomarkers or treatment targets for cardiovascular diseases. Hsa-miR-6086, a novel mi-RNA, was reported to be downregulated during the differentiation of human embryonic stem cells into endothelial cells (ECs). Interestingly, CDH5 (cadherin 5), encoding a classical cadherin of the cadherin superfamily, is a cellular marker of ECs and has been reported to be a target of hsa-miR-6086. However, the role of hsa-miR-6086 in ECs is virtually unknown. Herein, we report that hsa-miR-6086 was markedly induced by TNFα stimulation in human umbilical vein endothelial cells (HUVECs), whereas CDH5 expression was greatly reduced. Importantly, TNFα-induced suppression of CDH5 expression was largely prevented by inhibiting hsa-miR-6086, and hsa-miR-6086 mimic greatly decrease CDH5 expression in HUVECs, suggesting that the induction of hsa-miR-6086 is responsible for CDH5 downregulation by TNFα. In addition, restoration of CDH5 expression level by either inhibiting hsa-miR-6086 or exogenously expressing CDH5 cDNA that is not affected by hsa-miR-6086 protected HUVECs against TNFα-induced apoptosis and cell growth inhibition. Taken together, our study reveals that hsa-miR-6086 is induced by TNFα and mediates TNFα-induced HUVEC growth inhibition through downregulating CDH5 expression. Hence, hsa-miR-6086 might be a new target for treating TNFα-induced endothelial dysfunction.