miR-21 Inhibitor Research Articles

Investigating miR-9 as a mediator in laryngeal cancer health disparities.

For several decades, Black patients have carried a higher burden of laryngeal cancer among all races. Even when accounting for sociodemographics, a disparity remains. Differentially expressed microRNAs have been linked to racially disparate clinical outcomes in breast and prostate cancers, yet an association in laryngeal cancer has not been addressed. In this study, we present our computational analysis of differentially expressed miRNAs in Black compared with White laryngeal cancer and further validate microRNA-9-5p (miR-9-5p) as a potential mediator of cancer phenotype and chemoresistance. Bioinformatic analysis of 111 (92 Whites, 19 Black) laryngeal squamous cell carcinoma (LSCC) specimens from the TCGA revealed miRNAs were significantly differentially expressed in Black compared with White LSCC. We focused on miR-9-5 p which had a significant 4-fold lower expression in Black compared with White LSCC (p<0.05). After transient transfection with either miR-9 mimic or inhibitor in cell lines derived from Black (UM-SCC-12) or White LSCC patients (UM-SCC-10A), cellular migration and cell proliferation was assessed. Alterations in cisplatin sensitivity was evaluated in transient transfected cells via IC50 analysis. qPCR was performed on transfected cells to evaluate miR-9 targets and chemoresistance predictors, ABCC1 and MAP1B. Northern blot analysis revealed mature miR-9-5p was inherently lower in cell line UM-SCC-12 compared with UM-SCC-10A. UM -SCC-12 had baseline increase in cellular migration (p < 0.01), proliferation (p < 0.0001) and chemosensitivity (p < 0.01) compared to UM-SCC-10A. Increasing miR-9 in UM-SCC-12 cells resulted in decreased cellular migration (p < 0.05), decreased proliferation (p < 0.0001) and increased sensitivity to cisplatin (p < 0.001). Reducing miR-9 in UM-SCC-10A cells resulted in increased cellular migration (p < 0.05), increased proliferation (p < 0.05) and decreased sensitivity to cisplatin (p < 0.01). A significant inverse relationship in ABCC1 and MAP1B gene expression was observed when miR-9 levels were transiently elevated or reduced in either UM-SCC-12 or UM-SCC-10A cell lines, respectively, suggesting modulation by miR-9. Collectively, these studies introduce differential miRNA expression in LSCC cancer health disparities and propose a role for low miR-9-5p as a mediator in LSCC tumorigenesis and chemoresistance.

Engineered Cancer-Derived Small Extracellular Vesicle-Liposome Hybrid Delivery System for Targeted Treatment of Breast Cancer

Cancer-derived small extracellular vesicles (sEVs) may be a promising drug delivery system that targets cancer cells due to their unique features, such as native homing ability, biological barrier crossing capability, and low immune response. However, the oncogenic cargos within them pose safety concerns, hence limiting their application thus far. We proposed using an electroporation-based strategy to extract the endogenous cargos from cancer-derived sEVs and demonstrated that their homing ability was still retained. A membrane fusion technique was used to fuse these sEVs with liposomes to form hybrid particles, which possessed both benefits of sEVs and liposomes. Anti-EGFR monoclonal antibodies were modified on the hybrid particles to improve their targeting ability further. The engineered hybrid particles showed higher drug loading ability that is 33.75 and 43.88% higher than that of liposomes and sEVs, respectively, and improved targeting ability by 52.23% higher than hybrid particles without modification. This delivery system showed >90% cell viability and enhanced treatment efficiency with 91.58 and 79.26% cell migration inhibition rates for the miR-21 inhibitor and gemcitabine, respectively.

MiR-124 is upregulated in diabetic mice and inhibits proliferation and promotes apoptosis of high-glucose-induced β-cells by targeting EZH2.

Diabetes is a chronic metabolic disease, and a variety of miRNA are involved in the occurrence and development of diabetes. In clinical studies, miR-124 is highly expressed in the serum of patients with diabetes and in pancreatic islet β-cells. However, few reports exist concerning the role and mechanism of action of miR-124 in diabetes. To investigate the expression of miR-124 in diabetic mice and the potential mechanism of action in islet β-cells. The expression levels of miR-124 and enhancer of zeste homolog 2 (EZH2) in pancreatic tissues of diabetic mice were detected. The targeted relationship between miR-124 and EZH2 was predicted by Targetscan software and verified by a double luciferase reporter assay. Mouse islet β-cells Min6 were grown in a high glucose (HG) medium to mimic a diabetes model. The insulin secretion, proliferation, cell cycle and apoptosis of HG-induced Min6 cells were detected after interference of miR-124a and/or EZH2. The expression of miR-124 was upregulated and EZH2 was downregulated in the pancreatic tissue of diabetic mice compared with control mice, and the expression of miR-124 was negatively correlated with that of EZH2. miR-124 was highly expressed in HG-induced Min6 cells. Inhibition of miR-124 promoted insulin secretion and cell proliferation, induced the transition from the G0/G1 phase to the S phase of the cell cycle, and inhibited cell apoptosis in HG-induced Min6 cells. EZH2 was one of the targets of miR-124. Co-transfection of miR-124 inhibitor and siRNA-EZH2 could reverse the effects of the miR-124 inhibitor in HG-induced Min6 cells. miR-124 is highly expressed in diabetic mice and HG-induced Min6 cells and regulates insulin secretion, proliferation and apoptosis of islet β-cells by targeting EZH2.

Serum Exosome-Derived MiR-7 Exacerbates Chronic Obstructive Pulmonary Disease by Regulating Macrophage Differentiation.

Polarization of macrophages and miR-7 have been reported to greatly influence the progress of chronic obstructive pulmonary disease (COPD). However, the interaction is unclear. We aimed to investigate the role of miR-7 in the serum exosome of COPD, thus further revealing the underlying mechanism of COPD. The study was conducted in 2022 in The Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University, Changzhou, China. COPD mouse model was established. Macrophages were sorted by flow cytometry assay. ELISA kits were used to detect the levels of TNF-α and IL-6. Exosomes were identified by confocal microscopy and PKH67 staining. RT-qPCR and western blot assay were performed to determine the mRNA and protein expressions. H&E staining assay was used to assess the tissue injury. CCK-8 assay was applied to evaluate cell viability. Luciferase reporter assay was used to confirm the binding between PIM1 and miR-7. The exosomes derived from the COPD mice serum exerted high level of miR-7, which induced M1 differentiation of macrophages and increased the secretion of proinflammatory factors in vivo and in vitro. The effects of exosomes from COPD mice could be inhibited by miR-7 inhibitor. Bioinformatic prediction, luciferase reporter assay, and western blot assay showed an interaction between miR-7 and PIM1. Further examination showed that miR-7 regulated macrophage activation and differentiation to M1 via PIM1 in vitro. miR-7 from serum exosomes might exacerbate COPD by stimulating macrophage differentiation to M1, supplying a potential therapeutic target for COPD treatment.

Long non‑coding RNA DSCAM‑AS1 functions as an oncogene in thyroid cancer via regulating miR‑211.

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

MiR-214 Expression Is Elevated in Chronic Rhinosinusitis Mucosa and Regulates Lipopolysaccharide-Mediated Responses in Undifferentiated Human Nasal Epithelial Cell Culture.

Chronic rhinosinusitis (CRS) is an inflammatory disorder of the upper airways. MicroRNAs (miRs) are reported to regulate several diverse physiological and pathological processes. This study aimed to evaluate the impact of miR-214 on lipopolysaccharide (LPS)-mediated inflammation, and mucin 5AC (MUC5AC) expression in human nasal epithelial cells. The expression of miR-214 was detected in CRS with polyps (CRSwNP) and CRS without polyps (CRSsNP) tissues. Cells were treated with LPS and a miR-214 inhibitor. The level of miR-214 was detected by quantitative real-time reverse transcriptase-PCR (qRT-PCR). The inflammatory cytokines (IL-6, IL-8, TNF, and IL-1β) and MUC5AC production were determined by qRT-PCR and ELISA. MUC5AC protein level was detected using western blot. Similarly, we determined the relationship between miR-214 and Sirtuin 1 (SIRT1) using the Dual luciferase activity assay. miR-214 was increased in CRSwNP and CRSsNP tissues. LPS triggered the expression of miR-214, while miR-214 inhibition diminished the level of miR-214. MiR-214 inhibition prevented LPS-mediated the production of inflammatory cytokines. LPS treatment augmented MUC5AC mRNA, protein levels, and secretion, whereas miR-214 loss inhibited MUC5AC production in the presence of LPS. SIRT1 is a direct target of miR-214. Impairing SIRT1 by siRNA (siSIRT1) or EX527 (a selective SIRT1 inhibitor) reversed the effects of miR-214 inhibitor on inflammation and MUC5AC expression. Furthermore, miR-214 depression inhibited the STAT3/GDF15 pathway via targeting SIRT1. Upregulation of STAT3 or GDF15 partly abolished the anti-inflammatory roles of miR-214 inhibitor. Taken together, miR-214 regulates LPS-mediated inflammation and MUC5AC expression via targeting SIRT1, and STAT3/GDF15 may involve in the regulation of miR-214 inhibitor on inflammation and MUC5AC expression.

Downregulation of miR-137 Facilitates CD4+ T Cell Pyroptosis in Systemic Lupus Erythematosus via Stimulating AMPK Pathway.

From the pathogenic mechanism point of view, systemic lupus erythematosus (SLE) features prominently in T lymphocyte apoptosis. Yet the regulatory mechanism underlying SLE cell apoptosis remains to be explored. This research intends to clarify the role played by miR-137 in SLE and the underlying mechanisms. Twenty SLE patients (SLE group) and twenty healthy controls (control group) were selected, from whom peripheral blood CD4+ T cells were isolated via magnetic-activated cell sorting. Reverse transcription-polymerase chain reaction (RT-PCR) quantified miR-137 and AMP-activated protein kinase (AMPK) in CD4+ T cells. Further, transfection of miR-137 mimics and inhibitors into CD4+ T cells was carried out to alter miR levels. Levels of pyroptosis, apoptosis, and inflammatory- and pyroptosis-related proteins were determined through PI staining, flow cytometry, and Western blotting, respectively. A luciferase reporter gene assay identified the targeting relation between miR-137 and AMPK. SLE patients showed downregulated miR-137 and upregulated AMPK in CD4+ T cells than controls. miR-137 upregulation by miR-137 mimic transfection inhibited Jurkat cell pyroptosis and apoptosis at both mRNA and protein levels and suppressed NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome activity and pyroptosis-related protein gasdermin D (GSDMD), while miR-137 inhibitor transfection contributed to completely opposite effects. miR-137 directly targeted AMPK, as indicated by the luciferase reporter gene assay. Furthermore, miR-137 inhibitor intervention induced healthy CD4+ T cell pyroptosis and apoptosis via mediating AMPK, whereas miR-137 mimic transfection into CD4+ T cells of SLE patients leads to opposite results. Upregulating miR-137 inhibits CD4+ T cell pyroptosis in SLE patients by modulating the AMPK pathway, suggesting the potential diagnostic and therapeutic role of miR-137 in SLE.

Effects of miR-107 on Breast Cancer Cell Growth and Death via Regulation of the PTEN/AKT Signaling Pathway.

Investigate the influence of miR-107 on breast cancer cell growth and death through the PTEN/AKT signaling pathway. As study subjects, the human breast cancer cell line MCF-7 and the normal breast cell line Hs 578Bst were chosen, and MCF-7 cells were, respectively, transfected with control miRNA and miR-107 inhibitor. CCK-8, flow cytometry, scratch assay, and Transwell assay were used to analyze the proliferation, apoptosis, and invasion, and in order to identify the proteins associated with apoptosis in each of the three categories, we used western blot analysis. Bcl-2, cleaved caspase-3, and cleaved caspase-9 expression, as well as PTEN/AKT signaling pathway-associated protein expression, are correlated. The expression of miR-107 in MCF-7 cells was significantly greater than that in Hs 578Bst cells, with a P < 0.05 difference; compared to the blank and miRNA control groups, the miR-107 inhibitor group had a P < 0.05 difference. P < 0.05 showed a decrease in proliferation (42.52) but no difference in proliferation between the blank and miRNA control groups (P > 0.05); the miR-107 inhibitor group had higher apoptosis (38.96) with P < 0.05 than the blank group (4.85) and the miRNA control group (5.89); there was no difference in apoptosis between the blank and miRNA groups (P > 0.05). There was no significant difference between the blank group and the miRNA control group with P > 0.05; compared with the blank group, the miR-107 inhibitor group had a lower expression of Bcl-2 protein (0.18), in addition to the degraded paradigms (0.73) and caspase-9 protein concentrations (0.79), respectively. The PTEN/AKT signaling pathway may be regulated by miR-107 to limit breast cancer cell growth and increase apoptosis, which suggests that miR-107 may be exploited as a tumor marker for therapeutic therapy.

Osteoblasts-Derived Exosomal lncRNA-MALAT1 Promotes Osteoclastogenesis by Targeting the miR-124/NFATc1 Signaling Axis in Bone Marrow-Derived Macrophages.

Emerging studies have explained the crucial role of non-coding RNA (lncRNA) in various pathological progressions. The study was designed to examine the role of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and miRNA-124 in the differentiation of osteoclasts, to provide new clues or evidences for the pathogenesis of periodontitis. We constructed an osteoblast-osteoclast Transwell co-culture system and osteoblast-derived exosomes (OB-exo) intervention model. We assessed the osteoclastogenesis as well as the level of lncRNA-MALAT1 and miRNA-124. The mechanism for lncRNA MALAT1 targeting miR-124 modulating the differentiation of osteoclasts was investigated by cell transfection, quantitative real-time reverse transcription PCR (RT-qPCR), Western blot, and Dual-Luciferase reporter assays. Osteoblast-derived exosomes were isolated and identified. Co-culture and OB-exo intervention can promote osteoclastogenesis, also significantly up-regulate the expression of MALAT1, while the level of miR-124 is the opposite. Transfection of cells with small interfering RNA (si-MALAT1) and miR-124 mimic decreased the formation of TRAP+ osteoclasts and inhibited the expression of NFATc1. However, the effect was reversed when transfected with miR-124 inhibitor and si-MALAT1. The Dual-Luciferase reporter assay confirmed the binding sites between MALAT1 and miR-124, and miR-124 and NFATc1. LncRNA MALAT1 functioned as an endogenous sponge by competing for miR-124 binding to regulate NFATc1 expression, accelerating the progression of osteoclastogenesis.

PVT1/miR-16/CCND1 axis regulates gastric cancer progression.

Long non-coding RNA plasmacytoma variant translocation 1 (PVT1) has been reported to be a vital modulator in tumorigenesis of gastric cancer (GC). However, the detailed regulatory mechanism of PVT1 in GC remains largely unclear. In this work, the expressions of PVT1 and microRNA-16 (miR-16) were detected by quantitative real-time PCR (qRT-PCR) in GC tissues and cell lines. GC cell lines NCI-N87 and MKN45 cell lines were chosen for the following assays. After PVT1 was overexpressed or depleted, CCK-8 and Transwell assays were performed to examine the cell viability and invasive capacity. Cell cycle was analyzed by flow cytometry. The expression of cyclin D1 (CCND1) at mRNA and protein levels was measured by qRT-PCR and western blot. The competitive endogenous RNA molecular mechanism among PVT1, miR-16 and CCND1 was verified by bioinformatics analysis, luciferase-reporter gene assay and RNA immunoprecipitation assay. In the present study, it was revealed that PVT1 expression was remarkably evaluated in GC tissues and cell lines than that in the corresponding control group. PVT1 positively regulated the proliferation, migration and cell cycle progression of GC cells. Besides, miR-16 was identified as a target of PVT1, and CCND1 was identified as a target of miR-16. The depletion of PVT1 promoted the expression of miR-16 and suppressed CCND1 expression. Moreover, either miR-16 inhibitor or CCND1 overexpression plasmid could reverse the promoting effects of PVT1 on the malignant biological behaviors of GC cells. In conclusion, PVT1 promoted CCND1 expression by negatively regulating miR-16 expression to enhance the viability, invasion and cell cycle progression of GC cells.

LncRNA MEG3 inhibits renal fibrinoid necrosis of diabetic nephropathy via the MEG3/miR-21/ORAI1 axis.

Diabetic nephropathy (DN) is one of the most common and lethal diabetic complications worldwide and is associated with a high risk of mortality. However, the exact mechanism behind its development is unknown. The mesangial cells (MCs) and non-coding RNAs are critical for DN, but it is unknown whether a MEG3/miR-21/ORAI1 regulatory axis exists in MCs. Hence, in this study, we aimed to understand whether the MEG3/miR-21/ORAI1 regulatory axis has a role in the pathophysiology of DN. We demonstrated that high-glucose stimuli downregulated MEG3 and ORAI1 expression while enhancing miR-21 expression. Exogenous miR-21 mimics inhibited ORAI1 expression, which was partially salvaged or reversed by MEG3 overexpression. Furthermore, RIP assay demonstrated that the beads labeled with AGO2 antibody could enrich more miR-21 and MEG3 than those labeled with control IgG antibody; both of them formed the RNA-induced silencing complex. Further, the biochemical indicators of db/db mice significantly improved, and renal fibrinoid necrosis was ameliorated using a miR-21 inhibitor. The MEG3/miR-21/ORAI1 axis regulates the manifestation of DN in diabetic mice and MCs, and the miR-21 inhibitor can be a potential therapeutic strategy to alleviate DN, once the presence of such an axis is found in humans.

Hypoxia-induced downregulation of microRNA-186-5p in endothelial cells promotes non-small cell lung cancer angiogenesis by upregulating protein kinase C alpha

The tumor microenvironment stimulates the angiogenic activity of endothelial cells (ECs) to facilitate tumor vascularization, growth, and metastasis. The involvement of microRNA-186-5p (miR-186) in regulating the aberrant activity of tumor-associated ECs has so far not been clarified. In the present study, we demonstrated that miR-186 is significantly downregulated in ECs microdissected from human non-small cell lung cancer (NSCLC) tissues compared with matched non-malignant lung tissues. Invitro analyses of primary human dermal microvascular ECs (HDMECs) exposed to different stimuli indicated that this miR-186 downregulation is triggered by hypoxia viaactivation of hypoxia-inducible factor 1 alpha (HIF1α). Transfection of HDMECs with miR-186 mimic (miR-186m) significantly inhibited their proliferation, migration, tube formation, and spheroid sprouting. In contrast, miR-186 inhibitor (miR-186i) exerted pro-angiogenic effects. Invivo, endothelial miR-186 overexpression inhibited the vascularization of Matrigel plugs and the initial growth of tumors composed of NSCLC cells (NCI-H460) and HDMECs. Mechanistic analyses revealed that the gene encoding for protein kinase C alpha (PKCα) is a bona fide target of miR-186. Activation of this kinase significantly reversed the miR-186m-repressed angiogenic activity of HDMECs. These findings indicate that downregulation of miR-186 in ECs mediates hypoxia-stimulated NSCLC angiogenesis by upregulating PKCα.

CircRNA-SMO upregulates CEP85 to promote proliferation and migration of glioblastoma via sponging miR-326.

Circular RNAs (circRNAs) play an important role in cancer development by sponging microRNAs (miRNAs) to regulate the signaling axis. However, more comprehensive mechanisms of circRNAs in glioblastoma need to be elucidated. RT-qPCR was used to detect the expression levels of circRNA-SMO and miR-326. Dual-luciferase reporter assays were conducted to verify the interaction among circRNA-SMO, miR-326, and CEP85. Flow cytometric analysis was performed to detect apoptosis. Western blotting was used to determine the protein levels of the different molecules. Animal xenograft experiments were performed to evaluate the role of circRNA-SMO in vivo. CircRNA-SMO was upregulated in glioblastoma tissues and glioblastoma cells. CircRNA-SMO downregulation inhibited the viability and colony-forming ability of the glioblastoma cells. In addition, miR-326 was downregulated in glioblastoma cells, which was verified to sponge circRNA-SMO and interact with CEP85. Moreover, circRNA-SMO inhibition induced the elevation of miR-326 and apoptosis, accompanied by a decrease in CEP85. CircRNA-SMO knockdown-mediated tumor inhibition was prevented by an miR-326 inhibitor. Furthermore, circRNA-SMO inhibition inhibited tumor growth in vivo, accompanied by an increase in miR-326 and a decline in CEP85 in tumor tissues. Conclusions. CircRNA-SMO sponges miR-326 to promote glioblastoma proliferation and migration by upregulating CEP85 expression. This study clarified the role of circRNA-SMO in the development of glioblastoma, providing novel insights for its treatment.

The Role and underlying mechanism of dental pulp stem cell-derived exosomal miR-31 in the treatment of osteoarthritis by targeting mTOR to enhance chondrocyte autophagy levels

IntroductionOsteoarthritis is the most prevalent musculoskeletal progressive disease that leads to functional impairment and decreased quality of life. However, the current treatments remain unsatisfactory. Recent studies reveal that exosomes derived from mesenchymal stem cells offer a promising approach to improve the pathological changes of osteoarthritis, cartilage tissue, and chondrocyte homeostasis.Material and methodsA randomized, controlled animal experiment was conducted on nine-week-old male C57BL/6 mice that were obtained from Charles River Laboratories. In this in vitro and in vivo study, we studied the role and mechanisms of dental pulp stem cell-derived exosomes (DPSCs-exosomes) on osteoarthritis in the mouse model.ResultsThe study findings showed that a dental pulp stem cell could generate typical-characteristic exosomes. The injection of DPSCs-exosomes ameliorated destruction of cartilage, promoted matrix synthesis, inhibited cell apoptosis, and decreased the catabolic factors expression. However, this effect was shown to be almost eliminated when miR-31 antagomir was injected.ConclusionsFurthermore, DPSCs-exosomes show an ability to promote autophagy in chondrocytes through mTOR inhibition, in addition to reducing the mTOR luciferase activity. The ability of DPSCs-exosomes to partially regulate autophagy was blocked upon inhibition of miR-31. In brief, DPSCs-exosomes have a chondroprotective role in the mice osteoarthritis model. The underlying mechanism is possibly related to miR-31-mediated suppression of the mTOR-autophagy pathway.

Hypoxia-Elicited Mesenchymal Stem Cell-Derived Small Extracellular Vesicles Alleviate Myocardial Infarction by Promoting Angiogenesis through the miR-214/Sufu Pathway.

Myocardial infarction is a leading cause of mortality worldwide. Angiogenesis in the infarct border zone is vital for heart function restoration after myocardial infarction. Hypoxia-induced MSC modification is a safe and effective approach for angiogenesis in clinical therapy; however, the mechanism still requires further investigation. In our study, we preconditioned human umbilical cord mesenchymal stem cells (huMSCs) with hypoxia and isolated the small extracellular vesicles (sEVs) to promote cardiac repair. We also investigated the potential mechanisms. huMSCs were preconditioned with hypoxia (1% O2 and 5% CO2 at 37°C for 48 hours), and their sEVs were isolated using the Total Exosome Isolation reagent kit. To explore the role of miR-214 in MSC-derived sEVs, sEVs with low miR-214 expression were prepared by transfecting miR-214 inhibitor into huMSCs before hypoxia pretreatment. Scratch assays and tube formation assays were performed in sEVs cocultured with HUVECs to assess the proangiogenic capability of MSC-sEVs and MSChyp-sEVs. Rat myocardial infarction models were used to investigate the ability of miR-214-differentially expressed sEVs in cardiac repair. Echocardiography, Masson's staining, and immunohistochemical staining for CD31 were performed to assess cardiac function, the ratio of myocardial fibrosis, and the capillary density after sEV implantation. The potential mechanism by which MSChyp-sEVs enhance angiogenesis was explored in vitro by RT-qPCR and western blotting. Tube formation and scratch assays demonstrated that the proangiogenic capability of huMSC-derived sEVs was enhanced by hypoxia pretreatment. Echocardiography and Masson's staining showed greater improvements in heart function and less ventricular remodeling after MSChyp-sEV transplantation. The angiogenic capability was reduced following miR-214 knockdown in MSChyp-sEVs. Furthermore, Sufu, a target of miR-214, was decreased, and hedgehog signaling was activated in HUVECs. We found that hypoxia induced miR-214 expression both in huMSCs and their sEVs. Transplantation of MSChyp-sEVs into a myocardial infarction model improved cardiac repair by increasing angiogenesis. Mechanistically, MSChyp-sEVs promote HUVEC tube formation and migration by transferring miR-214 into recipient cells, inhibiting Sufu expression, and activating the hedgehog pathway. Hypoxia-induced vesicle modification is a feasible way to restore heart function after myocardial infarction.

Is miR-21 A Therapeutic Target in Cardiovascular Disease?

microRNA-21 (miR-21) serves a multitude of functions at the molecular level through its regulation of messenger RNA. Previous research has sparked interest in the role of miR-21 as a potential therapeutic target in cardiovascular diseases. miR-21 expression contributes to the differentiation, proliferation, and maturation of many cell types, such as fibroblasts, endothelial cells, cardiomyocytes, and endothelial progenitor cells. The function of miR-21 depends upon its expression level in the specific cell types and downstream targets, which determine cell fate. Under pathological conditions, the expression level of miR-21 is altered, leading to abnormal gene regulation of downstream signaling and cardiovascular diseases such as hypertension, cardiac hypertrophy and fibrosis, atherosclerosis, and heart failure. Agomirs or antagomirs can be introduced into the respective tissue type to reverse or stop the progression of the disease. Exosomes in the extracellular vesicles, which mediate many cellular events with high biocompatibility, have a high potential of efficiently delivering miR-21 to their targeted cells. The critical role of miR-21 in cardiovascular disease (CVD) is indisputable, but there are controversial reports on the function of miR-21 in the same disease. This discrepancy sparks interest in better understanding the role of miR-21 in different tissues under different stages of various diseases and the mechanism of how miR-21 inhibitors work.

Circ_0101692 knockdown retards the development of clear cell renal cell carcinoma through miR-384/FN1 pathway

PurposeCircular RNA_0101692 (circ_0101692) is overexpressed in clear cell renal cell carcinoma (ccRCC) by microarray analyses. However, its function and action mechanism in ccRCC tumorigenesis is still elusive. MethodsWestern blotting and qRT-PCR were executed to assess the circ_0101692, miR-384 and FN1 expression in ccRCC cells and tissues. Target relationships among them were determined via dual luciferase reporter and/or RNA immunoprecipitation assays. Cell proliferation was evaluated by CCK-8 assay. Caspase-3 activity assay was utilized to analyze cell apoptosis. To find out whether ccRCC cells might migrate, a transwell assay was performed. To assess the effects of circ_0101692 on tumor development in vivo, a mouse xenograft model was used. ResultsHigh expression of circ_0101692 and FN1, and decreased miR-384 were determined in ccRCC. Cell growth, migration and viability were decreased whereas cell apoptosis was stimulated when circ_0101692 was knockdown. miR-384 inhibitor transfection attenuated the inhibiting impacts of circ_0101692 silencing on ccRCC cell progression. FN1 deletion further inverted the cancer-promoting effect of miR-384 downregulation on cell viability and migration. In addition, circ_0101692 could sponge miR-384 to relieve the inhibition of miR-384 on FN1 in ccRCC. ConclusionsCirc_0101692 targeted miR-384/FN1 axis to facilitate cell proliferation, migration and repress apoptosis, thereby accelerating the development of ccRCC. This points out that circ_0101692/miR-384/FN1 axis might be a prospective target implemented for the future treatment of ccRCC.

MiR-145 Alleviates Smooth Muscle Cell Phenotype Transition via ADAM17-Mediated ACE2 Shedding.

It has been shown that miR-145 is involved in the differentiation of vascular smooth muscle cells (VSMCs) and may regulate vascular remodeling. However, the molecular mechanisms behind these pathological processes in hypertension are not fully elucidated. The present study was to examine whether miR-145 modulates phenotypic transformation of VSMCs under normal state and synthetic state and to explore the possible role of ADAM17-mediated ACE2 shedding and ACE2-Ang-(1-7)-Mas receptor axis. Wistar rats were fed with high-sucrose/high-fat diet for 30 weeks to establish a metabolic hypertension animal model. VSMCs were cultured and treated with Ang II with or without miR-145 mimics or miR-145 inhibitor. Results showed the expression of contractile markers α-SMA and SM22α, miR-145, ACE2, and Mas receptor reduced in the thoracic aorta of metabolic hypertensive rats (MHRs), while that of synthetic marker OPN increased as compared to the control group. In in vitro study, miR-145 inhibitor inhibited the expression of α-SMA, SM22α, ACE2, Mas receptor, and the Ang-(1-7) excretion and induced the expression of synthetic markers OPN, EREG, and MMP2. However, miR-145 mimic produced opposite effects on the VSMCs. In addition, in the synthetic VSMC induced by Ang II, miR-145 inhibitor partially reversed the induced expression of OPN, EREG, and MMP2 by Ang II, while further decreasing the expression of α-SMA and SM22α and ACE2-Ang-(1-7)-Mas receptor. Cotreatment with ADAM17 siRNA partially reversed the inducible effect of miR-145 inhibitor on the EREG and MMP2, induced Ang-(1-7) excretion, and upregulated ACE2 and Mas receptor expression. In conclusion, miR-145 alleviates phenotype transition from contractile to synthetic type via ADAM17-mediated ACE2 shedding in VSMCs and retains the activation of ACE2-Ang-(1-7)-Mas axis, which may benefit the vascular structural remodeling in the metabolic hypertension.

Silencing of long noncoding RNA X-inactive specific transcript alleviates Aβ1-42-induced microglia-mediated neurotoxicity by shifting microglial M1/M2 polarization.

This experimental study aims to investigate the role of long noncoding RNA X-inactive specific transcript (lncRNA XIST) in the microglial polarization and microglia-mediated neurotoxicity in Alzheimer's disease (AD). The levels of XIST and microRNA-107 (miR-107) were detected by quantitative real-time polymerase chain reaction. The spatial learning and memory capability of APPswe/PS1dE9 (APP/PS1) mice were evaluated by the Morris water maze test. The morphology of mouse hippocampus cells was evaluated by hematoxylin and eosin staining. The Iba1-positive microglia were labeled by immunohistochemistry staining. The protein levels were determined by western blot and enzyme-linked immunosorbent assay. Neurotoxicity was evaluated by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, caspase-3 activity, and Cell Counting Kit-8 assay. The XIST, miR-107, and AD targets were predicted by bioinformatics analysis. The level of XIST was increased in APP/PS1 mice, and XIST silencing ameliorated AD progression. XIST silencing suppressed microglia activation, microglial M1 polarization, and proinflammatory factor levels, but promoted microglial M2 polarization in APP/PS1 mice and Aβ1-42-treated BV-2 cells. XIST knockdown reduced Aβ1-42-induced microglia-mediated apoptosis and enhanced cell viability in HT22 cells. XIST silencing down-regulated miR-107 level and attenuated Aβ1-42-caused suppression of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling. Those effects of XIST silencing were attenuated by miR-107 inhibitor or LY294002. Downregulation of XIST lessened Aβ1-42-induced microglia-mediated neurotoxicity by modulating microglial M1/M2 polarization, which may be mediated by the miR-107/PI3K/Akt pathway.

MiR-140 Aggravates Chronic Obstructive Pulmonary Disease by Inducing Oxidative Stress in Diaphragm Cells by Targeting Nuclear Factor Erythroid 2-Related Factor 2

Our research proposes to explore the function of miR-140 in the development of COPD. A COPD model was established in rats, and bronchial epithelial cells (BECs) were extracted in the present study, followed by transfection with mimic NC+inhibitor NC, miR-144 mimic, and miR-144 inhibitor. Significantly higher apoptotic rate; downregulated Bcl-2; upregulated Bax and caspase-3; promoted production of IL-6, IL-1β, and MCP-1; higher ROS and MDA levels; lower SOD activity; and inactivated Nrf2 signaling were observed in miR-140 mimic-treated BECs, with opposite results observed in miR-140 inhibitor-treated BECs. The binding site between miR-140 and the 3′UTR region of Nrf2 was predicted and verified using the dual-luciferase gene reporter assay. COPD rats were administered with NC (agomir-NC and antagomir-NC), agomir-140, and antagomir-140. Compared to sham, dramatically lower pulmonary function, higher wet/dry value, severe pathological changes in lung tissues, higher release of inflammatory factors, enhanced apoptosis, higher ROS and MDA levels, lower SOD activity, and inactivated Nrf2 signaling were observed in the model and NC groups, which were greatly aggravated by agomir-140 and significantly reversed by antagomir-140. Collectively, our data suggest that miR-140 aggravates COPD by inducing OS in diaphragm cells by targeting Nrf2.