miRNA Inhibitors Research Articles

Effect of miR-195 inhibition on human skeletal muscle-derived stem/progenitor cells.

The application of a circulating miR-195 inhibitor could be a helping factor in the in vitro model of human skeletal muscle-derived stem/progenitor cells (SkMDS/PCs). Previously, microRNA-195 (miR-195) expression has been reported to be a negative factor for myogenesis. The study aimed to obtain anti-apoptotic and anti-aging effects in in vitro cultured myoblasts and to improve their ability to form myotubes by suppressing miR-195 expression. Human wild-type (WT) SkMDS/PC cells incubated with control (nonspecific) miRNA inhibitor and miR-195-inhibited SkMDS/PCs were studied. Functional assays (myotube formation and cell aging), antioxidant, and myogenic gene expression analyses were performed at two time points, at the seventh and eleventh cell passages. Myotube formation was found to be almost 2-fold higher in the miR-195-inhibited SkMDS/PCs population (P < 0.05) compared to WT cells. miR-195 inhibition did not appear to affect cell aging or rejuvenate human SkMDS/PCs. Antioxidant (SOD3 and FOXO) gene expression was augmented in the miR-195-inhibited SkMDS/PCs population, but no positive effect on the remaining antioxidant genes (SOD1, SOD2, and catalase) was observed. A significant increase in MyoD gene expression with a concomitant decrease in MyoG (P < 0.05) was further documented in miR-195- -inhibited SkMDS/PCs compared to WT cells (the eleventh cell passage). The performed studies may lead to the preconditioning of myogenic stem cells to extend their potential for pro-regenerative activity. The miR-195 inhibitor may serve as a conditioning factor augmenting selective antioxidant gene expression and proliferative potential of SkMDS/PCs, but it does not have an impact on cell aging and/ or apoptosis.

Combined Treatment of Bronchial Epithelial Calu-3 Cells with Peptide Nucleic Acids Targeting miR-145-5p and miR-101-3p: Synergistic Enhancement of the Expression of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Gene.

The Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene encodes for a chloride channel defective in Cystic Fibrosis (CF). Accordingly, upregulation of its expression might be relevant for the development of therapeutic protocols for CF. MicroRNAs are deeply involved in the CFTR regulation and their targeting with miRNA inhibitors (including those based on Peptide Nucleic Acids, PNAs)is associated with CFTR upregulation. Targeting of miR-145-5p, miR-101-3p, and miR-335-5p with antisense PNAs was found to be associated with CFTR upregulation. The main objective of this study was to verify whether combined treatments with the most active PNAs are associated with increased CFTR gene expression. The data obtained demonstrate that synergism of upregulation of CFTR production can be obtained by combined treatments of Calu-3 cells with antisense PNAs targeting CFTR-regulating microRNAs. In particular, highly effective combinations were found with PNAs targeting miR-145-5p and miR-101-3p. Content of mRNAs was analyzed by RT-qPCR, the CFTR production by Western blotting. Combined treatment with antagomiRNAs might lead to maximized upregulation of CFTR and should be considered in the development of protocols for CFTR activation in pathological conditions in which CFTR gene expression is lacking, such as Cystic Fibrosis.

Human endothelial cell-derived exosomal microRNA-99a/b drives a sustained inflammatory response during sepsis by inhibiting mTOR expression.

The pathophysiology of sepsis and its accompanying hyper-inflammatory response are key events that lead to multi-organ failure and death. A growing body of literature now suggests that the vascular endothelium plays a critical role in driving early events of sepsis progression. In this study, we demonstrate how endothelial-derived exosomes contribute to a successive pro-inflammatory phenotype of monocytes. Exosomes isolated from S. aureus infected endothelial cells drive both CD11b and MHCII expression in monocytes and contribute dysregulated cytokine production. Conversely, healthy endothelial exosomes had no major effect. microRNA (miRNA) profiling of exosomes identified miR-99 upregulation which we hypothesised as driving this phenotypic change through mechanistic target of rapamycin (mTOR). Knockdown of mTOR with miR-99a and miR-99b mimetics in S. aureus infected monocytes increased IL-6 and decreased IL-10 production. Interestingly, inhibition of miRNAs with antagomirs has the opposing effect. Collectively, endothelial exosomes are driving a pro-inflammatory phenotype in monocytes through dysregulated expression of miR-99a and miR-99b.

CircGSAP regulates the cell cycle of pulmonary microvascular endothelial cells via the miR-942-5p sponge in pulmonary hypertension.

Background We recently demonstrated that circGSAP was diminished in lung tissues from patients with pulmonary arterial hypertension and in hypoxia-induced pulmonary microvascular endothelial cells (PMECs). However, the underlying role of circGSAP in PMECs remains unknown. The study aimed to investigate the contribution of circGSAP to proliferation, apoptosis and cell cycle of PMECs in hypoxic environment and explore the mechanism. Methods The expression of circGSAP was quantified by real-time PCR or immunofluorescence in human lung tissue and PMECs. CircGSAP plasmid, circGSAP small interfering RNA (siRNA), miRNA inhibitor and target gene siRNA were synthesized to verify the role of circGSAP on regulating the proliferation, apoptosis, and cell cycle of PMECs. Results CircGSAP levels were decreased in lungs and plasma of patients with pulmonary hypertension second to chronic obstructive pulmonary disease (COPD-PH) and were associated with poor outcomes of COPD-PH patients. Upregulation of circGSAP inhibited proliferation, apoptosis resistance and G1/S transition of PMECs. Dual luciferase reporter assays showed that circGSAP acted as a competitive endogenous RNA regulating miR-942-5p, and identified SMAD4 as a target gene of miR-942-5p, Then, we verified the functions of miR-942-5p and SMAD4 in PMECs. In addition, the effect of circGSAP siRNA on PMECs was mitigated by transfection of miR-942-5p inhibitor, and the effect of miR-942-5p inhibitor on PMECs was inhibited by SMAD4 siRNA. Conclusion Our findings demonstrated that diminished circGSAP accelerated cell cycle to facilitate cell proliferation and apoptosis resistance through competitively binding miR-942-5p to modulate SMAD4 expressions in hypoxia-induced PMECs, indicating potential therapeutic strategies for PH.

Mesenchymal stromal cells-derived extracellular vesicles reprogramme macrophages in ARDS models through the miR-181a-5p-PTEN-pSTAT5-SOCS1 axis

RationaleA better understanding of the mechanism of action of mesenchymal stromal cells (MSCs) and their extracellular vesicles (EVs) is needed to support their use as novel therapies for acute respiratory...

Persistent TLR4 Activation Promotes Hepatocellular Carcinoma Growth through Positive Feedback Regulation by LIN28A/Let-7g miRNA

Chronic inflammation caused by liver damage or infection plays an important role in the development and progression of hepatocellular carcinoma (HCC). The activation of Toll-like receptors 4 (TLR4) is involved in HCC tumorigenesis. Moreover, high TLR4 expression in HCC has been linked to poor prognosis. Although the expression of TLR4 in HCC is relatively low compared to hematopoietic cells, it is important to explore the molecular mechanism leading to the elevation of TLR4 in HCC. In this study, we aimed to investigate the positive regulating loop for TLR4 expression in HCC in response to chronic inflammation. Our results confirm that the mRNA expression of TLR4 and proinflammatory cytokines, including interleukin 6 (IL6) and C-C motif chemokine ligand 2 (CCL2), positively correlate in human HCC samples. High TLR4 expression in HCC is more susceptible to lipopolysaccharide (LPS); TLR4 activation in HCC provides growth and survival advantages and thus promotes tumorigenesis. It has been shown that the LIN28/let-7 microRNA (miRNA) axis is a downstream effector of the TLR4 signal pathway, and let-7 miRNA is a potential post-transcriptional regulator for TLR4. Thus, we investigated the correlation between TLR4 and LIN28A mRNA and let-7g miRNA in HCC clinical samples and found that the expression of TLR4 was positively correlated with LIN28A and negatively correlated with let-7g miRNA. Moreover, by culturing PLC/PRF5 (PLC5) HCC cells in low-dose LPS-containing medium to mimic chronic inflammation for persistent TLR4 activation, the mRNA and protein levels of TLR4 and LIN28A were elevated, and let-7g miRNA was decreased. Furthermore, the 3’ untranslated region (3’UTR) of TLR4 mRNA was shown to be the target of let-7g miRNA, suggesting that inhibition of let-7g miRNA is able to increase TLR4 mRNA. While parental PLC5 cells have a low susceptibility to LPS-induced cell growth, long-term LPS exposure for PLC5 cells leads to increased proliferation, cytokine expression and stemness properties. In conclusion, our studies demonstrate positive feedback regulation for chronic TLR4 activation in the modulation of TLR4 expression level through the LIN28A/let-7g pathway in HCC and suggest a connection between chronic inflammation and TLR4 expression level in HCC for promoting tumorigenesis.

MiRNA novel_268 targeting NlABCG3 is involved in nitenpyram and clothianidin resistance in Nilaparvata lugens

The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the most destructive pests that seriously threatens the high-quality and safe production of rice. However, due to the unscientific use of chemical insecticides, N. lugens has developed varying levels of resistance to insecticides, including nitenpyram and clothianidin. The ATP-binding cassette (ABC) transporter plays a nonnegligible role in phase III of the detoxification process, which may play an important role in insecticide resistance. In the present study, NlABCG3 was significantly overexpressed in both the NR and CR populations compared with susceptible populations. Silencing NlABCG3 significantly increased the susceptibility of BPH to nitenpyram and clothianidin. In addition, RNAi-mediated knockdown of three key genes in the miRNA biogenesis pathway altered the level of NlABCG3. Subsequently, the luciferase reporter assays demonstrated that novel_268 binds to the NlABCG3 coding region and downregulates its expression. Furthermore, injection of miRNA inhibitors or mimics of novel_268 significantly altered the susceptibility of N. lugens to nitenpyram and clothianidin. These results suggest that miRNA novel_268 targeting NlABCG3 is involved in nitenpyram and clothianidin resistance in N. lugens. These findings may help to enhance our knowledge of the transcriptional regulation of the ABC transporter that mediate insecticide resistance in N. lugens.

MiR-146b-5p regulates IL-23 receptor complex expression in chronic lymphocytic leukemia cells

AbstractChronic lymphocytic leukemia (CLL) cells express the interleukin-23 receptor (IL-23R) chain, but the expression of the complementary IL-12Rβ1 chain requires cell stimulation via surface CD40 molecules (and not via the B-cell receptor [BCR]). This stimulation induces the expression of a heterodimeric functional IL-23R complex and the secretion of IL-23, initiating an autocrine loop that drives leukemic cell expansion. Based on the observation in 224 untreated Binet stage A patients that the cases with the lowest miR-146b-5p concentrations had the shortest time to first treatment (TTFT), we hypothesized that miR-146b-5p could negatively regulate IL-12Rβ1 side chain expression and clonal expansion. Indeed, miR-146b-5p significantly bound to the 3′-UTR region of the IL-12Rβ1 mRNA in an in vitro luciferase assay. Downregulation of miR-146b-5p with specific miRNA inhibitors in vitro led to the upregulation of the IL-12Rβ1 side chain and expression of a functional IL-23R complex similar to that observed after stimulation of the CLL cell through the surface CD40 molecules. Expression of miR-146b-5p with miRNA mimics in vitro inhibited the expression of the IL-23R complex after stimulation with CD40L. Administration of a miR-146b-5p mimic to NSG mice, successfully engrafted with CLL cells, caused tumor shrinkage, with a reduction of leukemic nodules and of IL-12Rβ1–positive CLL cells in the spleen. Our findings indicate that IL-12Rβ1 expression, a crucial checkpoint for the functioning of the IL-23 and IL-23R complex loop, is under the control of miR-146b-5p, which may represent a potential target for therapy since it contributes to the CLL pathogenesis. This trial is registered at www.clinicaltrials.gov as NCT00917540.

S-Adenosylmethionine Inhibits Colorectal Cancer Cell Migration through Mirna-Mediated Targeting of Notch Signaling Pathway.

Metastasis is a leading cause of mortality and poor prognosis in colorectal cancer (CRC). Thus, the identification of new compounds targeting cell migration represents a major clinical challenge. Recent findings evidenced a central role for dysregulated Notch in CRC and a correlation between Notch overexpression and tumor metastasis. MicroRNAs (miRNAs) have been reported to cross-talk with Notch for its regulation. Therefore, restoring underexpressed miRNAs targeting Notch could represent an encouraging therapeutic approach against CRC. In this context, S-adenosyl-L-methionine (AdoMet), the universal biological methyl donor, being able to modulate the expression of oncogenic miRNAs could act as a potential antimetastatic agent. Here, we showed that AdoMet upregulated the onco-suppressor miRNAs-34a/-34c/-449a and inhibited HCT-116 and Caco-2 CRC cell migration. This effect was associated with reduced expression of migration-/EMT-related protein markers. We also found that, in colorectal and triple-negative breast cancer cells, AdoMet inhibited the expression of Notch gene, which, by luciferase assay, resulted the direct target of miRNAs-34a/-34c/-449a. Gain- and loss-of-function experiments with miRNAs mimics and inhibitors demonstrated that AdoMet exerted its inhibitory effects by upregulating miRNAs-34a/-34c/-449a. Overall, these data highlighted AdoMet as a novel Notch inhibitor and suggested that the antimetastatic effects of AdoMet involve the miRNA-mediated targeting of Notch signaling pathway.

MiR-208b/miR-21 Promotes the Progression of Cardiac Fibrosis Through the Activation of the TGF-β1/Smad-3 Signaling Pathway: An in vitro and in vivo Study.

BackgroundRegulatory molecule microRNAs (miRNAs) have been implicated in myocardial fibrosis. However, the specific mechanism by which they lead to myocardial fibrosis remains unclear. This study aimed to explore the roles of miR-208b, miR-21 and transforming growth factor-β1 (TGF-β1)/Smad-3 signaling pathway components in cardiac fibrosis development.Materials and MethodsThirty-six consecutive acute myocardial infarction (AMI) patients were included in this study. Plasma was collected on admission and at 24 h, 48 h and 6 d. The levels of plasma miR-208b, miR-21, TGF-β1, and Smad-3 were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and cardiac calcium protein T (cTnT) and creatine kinase isoenzyme (CK-MB) were detected by electrochemiluminescence analysis. H9C2 cells were exposed to hypoxia and divided into 4 groups (hypoxia treatment for 6 h, 24 h, 48 h, and 72 h). These stimulated cells were then transfected with miRNA inhibitors and mimics for gene overexpression and inhibition. RT-qPCR was used to detect the expression of miR-208b, miR-21, TGF-β1, and Smad-3, and western blot analysis was used to detect TGF-β1 and Smad-3 protein expression.ResultsThe plasma analysis showed cTnT and CK-MB expression peaked at 24 h after symptom onset; miR-208b, miR-21, TGF-β1, and Smad-3 levels showed no peak and increased gradually with time. Cell experiments revealed that miR-208b and TGF-β1 were upregulated along with increased hypoxia exposure; miR-21 expression peaked at 24 h and 72 h, with the highest peak at 72 h, and Smad-3 expression peaked at 6 h and 72 h, with the highest peak at 72 h. miR-208b and miR-21 expressions were positively correlated with TGF-β/Smad-3 expression. TGF-β1/Smad-3 mRNA and protein levels were elevated in the miR-208b and miR-21 overexpression groups and reduced in the miR-208b and miR-21 inhibition groups.ConclusionMiR-208b and miR-21 promote cardiac fibrosis progression through TGF-β1/Smad-3 signaling pathway activation.

The Role of microRNA in the Development, Diagnosis, and Treatment of Cardiovascular Disease: Recent Developments.

Since their discovery in 1993, microRNAs (miRNAs) have emerged as important regulators of many crucial cellular processes, and their dysregulation have been shown to contribute to multiple pathologic conditions, including cardiovascular disease (CVD). miRNAs have been found to regulate the expression of various genes involved in cardiac development and function and in the development and progression of CVD. Many miRNAs are master regulators fine-tuning the expression of multiple, often interrelated, genes involved in inflammation, apoptosis, fibrosis, senescence, and other processes crucial for the development of different forms of CVD. This article presents a review of recent developments in our understanding of the role of miRNAs in the development of CVD and surveys their potential applicability as therapeutic targets and biomarkers to facilitate CVD diagnosis, prognosis, and treatment. There are currently multiple potential miRNA-based therapeutic agents in different stages of development, which can be grouped into two classes: miRNA mimics (replicating the sequence and activity of their corresponding miRNAs) and antagomiRs (antisense inhibitors of specific miRNAs). However, in spite of promising preliminary data and our ever-increasing knowledge about the mechanisms of action of specific miRNAs, miRNA-based therapeutics and biomarkers have yet to be approved for clinical applications. SIGNIFICANCE STATEMENT: Over the last few years microRNAs have emerged as crucial, specific regulators of the cardiovascular system and in the development of cardiovascular disease, by posttranscriptional regulation of their target genes. The minireview presents the most recent developments in this area of research, including the progress in diagnostic and therapeutic applications of microRNAs. microRNAs seem very promising candidates for biomarkers and therapeutic agents, although some challenges, such as efficient delivery and unwanted effects, need to be resolved.

LncRNA FAM13A-AS1 Regulates Proliferation and Apoptosis of Cervical Cancer Cells by Targeting miRNA-205-3p/DDI2 Axis.

The aim of this study was to explore the function of long noncoding RNA (lncRNA) FAM13A-AS1 and its associated mechanism in cervical cancer. A total of 30 cervical cancer tissues and adjacent tissues were collected. Cervical cancer cell lines, including SiHa and HeLa, were transfected with constructs expressing LV-FAM13A-AS1, silencing RNA LV-siFAM13A-AS1, miRNA mimics, and miRNA inhibitors. RT-qPCR was used to detect the expression of FAM13A-AS1 in cervical cancer tissues, including SiHa, HeLa, and HUCEC cells. MTT, flow cytometry, and transwell assays were performed to explore the influence of FAM13A-AS1 on cervical cancer cell proliferation, apoptosis, invasion, and migration. A bioinformatics analysis and a dual-luciferase assay were carried to confirm the target relationship between FAM13A-AS1 or DDI2 and miRNA-205-3p. Finally, in vivo tumorigenesis experiments were performed in nude mice to explore the effect of FAM13A-AS1 expression on cervical cancer. Low FAM13A-AS1 expression and high miRNA-205-3p expression were observed in cervical cancer tissues and cell lines (SiHa and HeLa). Upregulating the expression of FAM13A-AS1 inhibited proliferation, migration, and invasion of SiHa and HeLa cells, while the apoptosis of SiHa and HeLa cells was increased. More importantly, LV-FAM13A-AS1 could improve tumor development in vivo. In addition, FAM13A-AS1 negatively regulated the expression of miRNA-205-3p, while miRNA-205-3p reduced DDI2 expression, and miRNA-205-3p mimic reversed the effects of FAM13A-AS1 overexpression in vitro. In conclusion, FAM13A-AS1 inhibits the progression of cervical cancer by targeting the miRNA-205-3p/DDI2 axis, suggesting that FAM13A-AS1 might be a potential target for cancer cell treatment.

Abstract 1487: Role of micro-RNA199a-3p in lymph node stromal extracellular vesicles on tumorigenesis in colorectal cancer

Abstract Introduction: MicroRNAs (miRNAs) are short non-coding RNAs implicated in post-transcriptional regulation of gene expression. Abnormal expression of miRNAs in cancer is associated with enhanced tumorigenesis and metastatic potential. Our previous data has shown that extracellular vesicles (EV) secreted by human lymph node stromal cells (LNSC) enhance tumorigenesis in colorectal cancer (CRC). By systemic searching and modifying miRNAs carried by EV through overexpression and inhibition on LNSC, we aim to demonstrate their effect on CRC progression in vitro and orthotopic mouse model. Methods: Total microRNA sequencing was analyzed using in-silico computer prediction models. Four overexpressed miRNAs in the LNSC-EV were selected (miR-155-5p, miR-199a-3p, mi-143-3p, and mi-214-3p). Tumor cell proliferation assay was performed using a CRC SW620 cell line transfected with selected miRNA mimics or inhibitors or controls. In our mouse model, miRNA transfected SW620 cells tagged with luciferase/RFP, were injected into the rectal submucosa of NOD/SCID mice. Tumor growth and metastases were observed by weekly bioluminescent imaging (BLI). At week 7, tumors were weighed and BLI of the tumors and organs were recorded. Immunohistochemistry staining was performed on the paraffin sections of tumors, livers and lung collected from these mice. Results: In vitro proliferation assays, cells transfected with the mimic of miRNA 199a-3p significantly increased CRC SW620 cell proliferation (p&amp;lt;0.01) while cells treated with the inhibitor showed decreased proliferation (p&amp;lt;0.05). In our orthotopic mouse model, mice with SW620 cells transfected with the mimic had increased frequencies of tumorigenesis (94% vs. 14%) and liver and lung metastasis comparing to control group (56% vs 9.5%, 50% vs 0%). Mice injected with SW620 cells transfected with the miRNA inhibitor had decreased tumor growth compared to the negative control (p&amp;lt;0.05). Conclusion: Our study shows that miRNAs carried in LNSC-EV are crucial for CRC progression. Specifically, inhibition of miRNA-199a-3p may serve as a therapeutic target in the treatment of CRC. Understanding the role and mechanisms of this miRNA in CRC could lead to the improved management of patients with CRC. Citation Format: Hallie Baer, Jessica Simon, Lara McKean-Baste, Alicia N. Ray, Heather Green, Grace Maresh, Xin Zhang, David Marjolin, Jennifer Paruch, Li Li. Role of micro-RNA199a-3p in lymph node stromal extracellular vesicles on tumorigenesis in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1487.

Focused ultrasound-induced targeted delivery of miR-155-5p inhibitor employing biomimetic microbubbles reduces NADPH oxidase expression and inflammation in atherosclerotic ApoE-/- mice

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UEFISCDI Background MicroRNAs are important biomarkers and potential therapeutic targets in atherosclerosis. MiR-155-5p amplifies inflammation in atherosclerosis by targeting negative regulators of NF-kB signaling pathway. Inhibition of pro-atherogenic miRNAs or mimicking the function of selected anti-atherogenic miRNAs have emerged as prospective oligonucleotide-base therapeutic interventions in order to correct the expression of key genes that are mechanistically linked to atherosclerotic lesion formation. Purpose The aim of this study was to develop a strategy to reduce oxidative stress and inflammation in atherosclerotic mice employing sterically stabilized biomimetic microbubbles (MB) as focused ultrasound-responsive targeted delivery systems of miR-155-5p inhibitor. Methods ApoE-/- mice were fed a normal (control) or a high-fat, cholesterol-rich diet for 14 weeks to accelerate de development of aortic atherosclerotic lesions. FAM-labelled miRNA negative control inhibitor, miRNA negative control inhibitor or miR-155-5p inhibitor were charge-coupled to VCAM1-targeted MB. Targeted MB were delivered to mice in a single dose via retro-orbital injection. Ultrasound imaging interrogation of atherosclerotic lesions in ApoE-/- mice was performed using a conventional 30 MHz transducer (Vevo 2100 System). The Sonidel SP100 sonoporator was used for ultrasound-induced targeted release of miRNA inhibitors in mice. The biodistribution of MB was monitored by high-resolution fluorescence imaging. Atherosclerotic lesions were assessed by Oil Red O staining. Real time PCR and Western blot were employed to determine the expression of NADPH oxidase (Nox) subtypes, a major source of oxidative stress, and markers of oxidative stress inflammation (4-HNE-protein adducts, inducible nitric oxide synthase/NOS2, CD68). Results Epi-fluorescence analysis demonstrated the enhanced uptake of FAM-labelled miRNA control inhibitor by lungs and the atherosclerotic aorta of ApoE-/- mice following ultrasound wave exposure (1 MHz, 2.0 w/cm2, 50% duty cycles, 15 minutes). The mRNA/protein levels of Nox1-4 subtypes, 4-HNE-protein adducts, NOS2, and macrophage infiltration marker CD68 were found significantly elevated in the atherosclerotic aorta of ApoE-/- mice. The expression levels of Nox isoforms, 4-HNE-protein adducts, NOS2, and CD68 were significantly decreased in the atherosclerotic aorta of ApoE-/- mice 1-week after administration of targeted MB carrying miR-155-5p inhibitor as compared with atherosclerotic ApoE-/- mice treated with targeted MB carrying miRNA negative control inhibitor. Conclusion Systemic administration of miR-155-5p inhibitor conjugated with VCAM1-targeted MB reduces the expression of oxidative stress and inflammation-related markers in experimental atherosclerosis. Ultrasound-induced targeted delivery of miRNA-oriented oligonucleotides could become an important theranostic strategy combining imaging and treatment procedures in clinical atherosclerosis.

Erxian herbal pair enhances bone formation in infected bone nonunion models and attenuates lipopolysaccharide-induced osteoblastinhibition by regulating miRNA-34a-5p

ABSTRACT Bacterium-induced inflammatory responses cause bone nonunion. Although antibiotics suppress infection, bone loss after antibacterial treatment remains a critical challenge. Erxian herbal pair (EHP) has been proven effective in promoting bone formation. Our study aimed to investigate the effect of EHP on bone repair after anti-infection treatment, explore its effect on a lipopolysaccharide (LPS)-induced osteoblast. We evaluated effects of EHP on bone repair with Micro-CT, and morphology detecting. Chemical constituents of EHP and EHP-containing serum (EHP-CS) were identified by UHPLC-Q/TOF-MS. In addition, osteoblast induced by LPS was established and administrated with EHP-CS. Cell proliferationwas assessed by MTT. Target prediction identified SMAD2 as a potential target of miRNA-34a-5p. MiRNA mimic, inhibitor and siRNA were transiently transfected into osteoblasts. The mRNA levels and protein expressions of miRNA-34a-5p, BMP2, Runx2, SMAD2 were assessed. The results showed that the main biocactivity ingredients in EHP-CS were Baohuoside Ι and Orcinol Glucoside. EHP could promote bone remolding after anti-infection therapy and restore the activity of LPS-induced osteoblasts. Moreover, miRNA-34a-5p was dramatically downregulated and SMAD2 was upregulated after LPS stimulation, while EHP resisted the inhibition of LPS by promoting miRNA-34a-5p, ALP, and BMP2 expressions. Whereas downregulation of miRNA-34a-5p reversed these effects. Silencing endogenous SMAD2 expression markedly promoted BMP2 and ALP activity and enhanced osteogenesis. Taken together, EHP restored LPS-induced bone loss by regulating miRNA-34a-5p levels and repressing its target gene SMAD2. EHP might be a potential adjuvant herbal remedy for the treatment of bone nonunion, and miRNA-34a-5p is a novel target for controlling bone and metabolic diseases.

Synergistic Effects of A Combined Treatment of Glioblastoma U251 Cells with An Anti-miR-10b-5p Molecule and An AntiCancer Agent Based on 1-(3',4',5'-Trimethoxyphenyl)-2-Aryl-1H-Imidazole Scaffold.

(1) Background: In the development of new and more effective anticancer approaches, combined treatments appear of great interest. Combination therapy could be of importance in the management of glioblastoma (GBM), a lethal malignancy that accounts for 42% of cancer of the central nervous system, with a median survival of 15 months. This study aimed to verify the activity on a glioblastoma cancer cell line of one of the most active compounds of a novel series of tubulin polymerization inhibitors based on the 1-(3′,4′,5′-trimethoxyphenyl)-2-aryl-1H-imidazole scaffold, used in combination with a miRNA inhibitor molecule targeting the oncomiRNA miR-10b-5p. This microRNA was selected in consideration of the role of miR-10b-5p on the onset and progression of glioblastoma. (2) Methods: Apoptosis was analyzed by Annexin-V and Caspase 3/7 assays, efficacy of the anti-miR-10b-5p was assessed by determining the miR-10b-5p content by RT-qPCR. (3) Results: The results obtained show that a “combination therapy” performed by combining the use of an anti-miR-10b-5p and a 1-(3′,4′,5′-trimethoxyphenyl)-2-aryl-1H-imidazole derivative is an encouraging strategy to boost the efficacy of anticancer therapies and at the same time to reduce side effects.

HBV induced the discharge of intrinsic antiviral miRNAs in HBV-replicating hepatocytes via extracellular vesicles to facilitate its replication.

Hepatitis B virus (HBV), which can cause chronic hepatitis B, has sophisticated machinery to establish persistent infection. Here, we report a novel mechanism whereby HBV changed miRNA packaging into extracellular vesicles (EVs) to facilitate replication. Disruption of the miRNA machinery in hepatocytes enhanced HBV replication, indicating an intrinsic miRNA-mediated antiviral state. Interference with EV release only decreased HBV replication if there was normal miRNA biogenesis, suggesting a possible link between HBV replication and EV-associated miRNAs. Microarray and qPCR analyses revealed that HBV replication changed miRNA expression in EVs. EV incubation, transfection of miRNA mimics and inhibitors, and functional pathway and network analyses showed that EV miRNAs are associated with antiviral function, suggesting that to promote survival HBV coopts EVs to excrete anti-HBV intracellular miRNAs. These data suggest a novel mechanism by which HBV maintains its replication, which has therapeutic implications.

AB0030 THE BIOLOGICAL FUNCTION AND MECHANISM EXPLORATION OF TACI IN SJOGREN’S SYNDROME

Backgroundprimary Sjogren’s syndrome (pSS) is a chronic autoimmune disease that affects the lacrimal, salivary and other exocrine glands. More and more studies have shown that B cells play a central role in the pathogenesis of SS.ObjectivesWe intended to explore the expression of the transmembrane activator, calcium modulator and cyclophilin ligand interactor (TACI) on the B cells, its role in pSS, and possible signal transduction pathways.MethodsWe included 34 naive pSS patients who visited the rheumatology department of Peking University First Hospital, and 37 gender- and age-distribution matched healthy controls (HCs). (1) To compare the B cell subsets, expression of TACI and relevant receptors in pSS patients, peripheral blood mononuclear cells were separated to analyze the ratio of B subsets, TACI, and BAFF-R by flow cytometry; ELISA was applied to detect the serum BAFF and soluble TACI (sTACI) concentration. (2) As for functional research of TACI, CD19+ B cells separated by magnetic sorting were treated under in vitro culture circumstances with raw TACI, TACI knocked down by siRNA, and sTACI analog (telitacicept) intervention with varing doses. The apoptosis, proliferation, differentiation and regulatory capacity on T cells were analyzed by flow cytometry, inflammatory cytokines and immunoglobulin levels in the culture supernatants were detected by CBA. (3) As for TACI-associated signaling pathway exploration, based on our previous miRNA data and relevant report of high quality, miRNA associated with TACI with significantly biased expression was confirmed by RT-qPCR. Screening the target gene of the candidate miRNA, and miRNA overexpression and inhibition experiments were conducted to validate the targeted relationship in B cells. And TACI-associated signaling pathway was explored via overexpressing and inhibiting the target gene.Results(1) Compared to HC, peripheral blood B subsets of pSS patients exhibited a significant bias, manifesting as increased proportion of CD19+CD24hiCD38hi Breg and decreased ratio of CD19+CD24+CD38- memory B cells. The expression of TACI in all B subsets was down-regulated, while that of BAFF-R was up-regulated. Both the serum concentration of BAFF and sTACI in pSS patients increased significantly. (2) As for functional research of TACI, in the setting of raw TACI, B cells in the pSS group showed higher apoptosis rate than HC under culture in vitro, where the ligand of TACI (APRIL or BAFF) addition turned the rate comparable; more active proliferation, and impaired capacity of inducing Treg cells to secrete IL-10. When TACI was knocked down by 50%, B cells performed less late apoptosis, significantly increased proliferation, impaired differentiation, significant dysfunction of Breg itself and impaired induction of Treg cells to secrete IL-10. While telitacicept intervention increased early apoptosis rate of B cells, significantly inhibited proliferation in 500ng/mL group and impaired ability of Breg and Treg cells to secrete IL-10. Besides, increased TACI on B cells treated with telitacicept, decreased IgG and increased IgA in the culture supernatants were observed. (3) As for TACI-associated signaling pathway exploration, hsa-miR-30b-5p showed satisfactory correlation between both transmembrane and sTACI. Besides, the expression of hsa-miR-30b-5p was significantly down-regulated, and inhibition its expression in vitro could lead to differentiation retard, impaired secretion of IL-10 by Breg cells. SMAD1 was screened based on database and validated as its target gene by overexpressing and inhibiting hsa-miR-30b-5p in B cell. After targeted up- or down-regulating the transcription of SMAD1 further, the transcription of ID2 downstream the TGF-β/Hippo signaling pathway changed accordingly.ConclusionThe expression of TACI on peripheral blood B cells was deficient in pSS patients. TACI deficiency was closely associated with the downregulation of hsa-miR-30b-5p, activating TGF-β/Hippo pathway mediated by its target gene SMAD1 and taking part in the pathogenesis of pSS.Disclosure of InterestsNone declared

MicroRNA Expression Profiling in Age-Dependent Renal Impairment.

BackgroundAge-dependent renal impairment contributes to renal dysfunction in both the general population and young and middle-aged patients with renal diseases. Pathological changes in age-dependent renal impairment include glomerulosclerosis and tubulointerstitial fibrosis. The molecules involved in age-dependent renal impairment are not fully elucidated. MicroRNA (miRNA) species were reported to modulate various renal diseases, but the miRNA species involved in age-dependent renal impairment are unclear. Here, we investigated miRNAs in age-dependent renal impairment, and we evaluated their potential as biomarkers and therapeutic targets.MethodsWe conducted an initial microarray profiling analysis to screen miRNAs whose expression levels changed in kidneys of senescence-accelerated resistant (SAMR1)-10-week-old (wk) mice and SAMR1-50wk mice and senescence-accelerated prone (SAMP1)-10wk mice and SAMP1-50wk mice. We then evaluated the expressions of differentially expressed miRNAs in serum from 13 older patients (>65 years old) with age-dependent renal impairment (estimated glomerular filtration ratio <60 mL/min/1.73 m2) by a quantitative real-time polymerase chain reaction (qRT-PCR) and compared the expressions with those of age-matched subjects with normal renal function. We also administered miRNA mimics or inhibitors (5 nmol) with a non-viral vector (polyethylenimine nanoparticles: PEI-NPs) to SAMP1-20wk mice to investigate the therapeutic effects.ResultsThe qRT-PCR revealed a specific miRNA (miRNA-503-5p) whose level was significantly changed in SAMP1-50wk mouse kidneys in comparison to the controls. The expression level of miRNA-503-5p was upregulated in the serum of the 13 patients with age-dependent renal impairment compared to the age-matched subjects with normal renal function. The administration of a miRNA-503-5p-inhibitor with PEI-NPs decreased the miRNA-503-5p expression levels, resulting in the inhibition of renal fibrosis in mice via an inhibition of a pro-fibrotic signaling pathway and a suppression of glomerulosclerosis in mice by inhibiting intrinsic signaling pathways.ConclusionThe serum levels of miRNA-503-5p were decreased in patients with age-dependent renal impairment. However, inhibition of miRNA-503-5p had no effect on age-dependent renal impairment, although inhibition of miRNA-503-5p had therapeutic effects on renal fibrosis and glomerulosclerosis in an in vivo animal model. These results indicate that miRNA-503-5p might be related to age-dependent renal impairment.

Multi-omics analysis revealed TEK and AXIN2 are potential biomarkers in multifocal papillary thyroid cancer

BackgroundPapillary thyroid carcinoma (PTC), the most common endocrine cancer, accounts for 80–85% of all malignant thyroid tumors. This study focused on identifying targets that affect the multifocality of PTC. In a previous study, we determined 158 mRNAs related to multifocality in BRAF-mutated PTC using The Cancer Genome Atlas.MethodsWe used multi-omics data (miRNAs and mRNAs) to identify the regulatory mechanisms of the investigated mRNAs. miRNA inhibitors were used to determine the relationship between mRNAs and miRNAs. We analyzed the target protein levels in patient sera using ELISA and immunohistochemical staining of patients’ tissues.ResultsWe identified 44 miRNAs that showed a negative correlation with mRNA expression. Using in vitro experiments, we identified four miRNAs that inhibit TEK and/or AXIN2 among the target mRNAs. We also showed that the downregulation of TEK and AXIN2 decreased the proliferation and migration of BRAF ( +) PTC cells. To evaluate the diagnostic ability of multifocal PTC, we examined serum TEK or AXIN2 in unifocal and multifocal PTC patients using ELISA, and showed that the serum TEK in multifocal PTC patients was higher than that in the unifocal PTC patients. The immunohistochemical study showed higher TEK and AXIN2 expression in multifocal PTC than unifocal PTC.ConclusionsBoth TEK and AXIN2 play a potential role in the multifocality of PTC, and serum TEK may be a diagnostic marker for multifocal PTC.