Exosomal miRNA Expression Research Articles

Serum exosomal miR-377-3p and miR-381-3p as diagnostic biomarkers in colorectal cancer.

Aim: This study aimed to identify specific and sensitive exosomal miRNAs in diagnosing patients with colorectal cancer (CRC). Methods: Serum exosomes were isolated from 175 CRC patients and 172 healthy donors by ultracentrifugationand identified by transmission electron microscopy, nanoparticle tracking analysisand western blotting. Exosomal miRNA expression wasdetected by quantitative PCR and the resultsanalyzed by receiver operating characteristicanalysis to illuminate the diagnostic accuracy. Results: Both exosomal miR-377-3p and miR-381-3p were downregulated in CRC patients as well as in early-stage patients compared with healthy donors; they could serve as circulating biomarkers of diagnosis, including early diagnosis, for CRC, possessing favorable diagnosticefficiency. Conclusion: Exosomal miR-377-3p and miR-381-3p levels were downregulated in CRC patients and may be usefulas novel and specific biomarkers for the diagnosis of CRC, especially early-stage CRC.

Evaluation of plasma exosomal miRNAs as potential diagnostic biomarkers of lymph node metastasis in papillary thyroid carcinoma.

The early diagnosis of lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) is clinically important, as it can aid in treatment decision-making and improve prognosis. In the present study, we aimed to identify whether plasma exosomal miRNAs could be potential diagnostic markers of LNM in PTC. Profiles of plasma exosomal miRNAs were screened using miRNA microarrays. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed in the validation and diagnostic sets to select candidate exosomal miRNAs. Finally, receiver operating characteristic (ROC) curves were generated to evaluate the efficiency of target exosomal miRNAs in distinguishing PTC-N1 patients from PTC-N0 patients. In total, 197 miRNAs were found to be differentially expressed in the testing set. Based on the qRT-PCR results, the expression of miR-6774-3p (p < 0.001) and miR-6879-5p (p < 0.001) in the PTC-N1 patients was significantly higher than that in the controls. The AUC values of plasma exosomal miR-6774-3p (0.802; 95% CI, 0.724-0.879) and miR-6879-5p (0.787; 95% CI, 0.706-0.867) and their combination (0.914; 95% CI, 0.865-0.962) were higher than those of the total miRNAs directly isolated from plasma. Moreover, the expression of exosomal miRNAs was stable after treatment with RNase A, prolonged incubation, or repeated freezing and thawing. The two plasma exosomal miRNAs (miR-6774-3p and miR-6879-5p) and their combination could serve as new promising biomarkers for the diagnosis of LNM in PTC patients.

Comprehensive Analyses of Type 1 Diabetes Ketosis- or Ketoacidosis-Related Genes in Activated CD56+CD16+ NK Cells.

ObjectivesAlterations in natural killer (NK) cells activity cause damage to pancreatic islets in type 1 diabetes mellitus (T1DM). The aim of this study is to identify T1DM ketosis- or ketoacidosis-related genes in activated CD56+CD16+ NK cells.MethodsMicroarray datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were analyzed using the GEO2R tool. Enrichment analyses were performed using Metascape online database and GSEA software. Cell-specific gene co-expression network was built using NetworkAnalyst tools. Cytoscape software was used to identify hub genes and construct co-expressed networks. Target miRNAs were predicted based on the DIANA-micro T, miRDB, and miRWalk online databases.ResultsA total of 70 DEGs were identified between T1DM patients recovered from ketosis or ketoacidosis and healthy control blood samples in GSE44314. Among the DEGs, 10 hub genes were screened out. The mature NK cell-specific gene co-expression network for DEGs in T1DM was built using NetworkAnalyst tools. DEGs between activated CD56+CD16+ NK cells and CD56brightCD16- NK cells were identified from GSE1511. After intersection, 13 overlapping genes between GSE44314 and GSE1511 microarray datasets were screened out, in which 7 hub genes were identified. Additionally, 59 target miRNAs were predicted according to the 7 hub genes. After validating with the exosome miRNA expression profile dataset of GSE97123, seven differentially expressed miRNAs (DEmiRNAs) in plasma-derived exosome were selected. Finally, a mRNA–miRNA network was constructed, which was involved in the T1DM ketosis or ketoacidosis process.ConclusionThis work identified seven hub genes in activated CD56+CD16+ NK cells and seven miRNAs in plasma-derived exosome as potential predictors of T1DM ketoacidosis, which provided a novel insight for the pathogenesis at the transcriptome level.

Aberrant expression profiles and bioinformatic analysis of CAF-derived exosomal miRNAs from three moderately differentiated supraglottic LSCC patients.

BackgroundAberrant expression of exosomal miRNAs has emerged as a research hotspot. However, no studies have been conducted on the dysregulation of exosomal miRNAs derived from cancer‐associated fibroblasts (CAFs) in supraglottic laryngeal squamous cell carcinoma (SLSCC).MethodsCancer‐associated fibroblasts and paired normal fibroblasts (NFs) from SLSCC patients were cultured, and exosomes in the culture supernatants were collected and identified. Exosomal miRNA expression was compared in each pair of CAFs and NFs by next‐generation sequencing, and expression of selected exosomal miRNAs was validated by reverse transcription‑quantitative PCR. Four online bioinformatic algorithms predicted the potential target genes of aberrantly expressed miRNAs, while gene ontology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment and network analysis identified downstream target genes and their interactions.ResultsThree pairs of CAFs and NFs were successfully cultured and purified. CAF‐derived exosomal miRNAs were mostly downregulated and included miR‐656‐3p, miR‐337‐5p, miR‐29a‐3p and miR‐655‐3p; however, some, including miR‐184‐3p, miR‐92a‐1‐5p, miR‐212‐3p and miR‐3135b, were upregulated. Bioinformatics analysis revealed involvement of these miRNAs in biological processes, cellular components and molecular functions. KEGG analysis revealed the top 30 pathways involvement in cancer initiation and progression and in cell cycle regulation. An interaction network showed miR‐16‐5p, miR‐29a‐3p, miR‐34c‐5p, miR‐32‐5p and miR‐490‐5p as the top five miRNAs and CCND1, CDKN1B, CDK6, PTEN and FOS as the top five target genes.ConclusionsSLSCC patients showed aberrant expression of CAF‐derived exosomal miRNAs. The top five miRNAs and their target genes may jointly constitute a carcinogenic tumour microenvironment and act as biomarkers for SLSCC intervention.

Extracellular vesicles-derived microRNAs expression as biomarkers for neurological radiation injury: Risk assessment for space exploration

Space missions pose threats to the health of the astronauts due to long-term exposure to galactic cosmic rays and solar particle events comprised predominantly of medium to high energy protons, energetic helium ions, and energetic high atomic number particles (HZEs). While the tissue-specific effects of radiation have been studied extensively, the changes in exosomal miRNA expression levels in response to acute radiation exposure have not been assessed. Extracellular vesicles (EVs) originate from the host cells and contain nucleic acid and proteins that can modify the physiology of the receiving cells via the transfer of genomic, proteomic, and lipids cargo. Detection and analysis of miRNA cargo of circulating EVs is an emerging method for non-invasive diagnosis and monitoring of neurological disorders. This study characterizes the EV-derived miRNA expression profiles of human astrocytes to identify those that are altered after treatment with 3 Gy proton radiation as biomarkers of neurological radiation injury. The relationship between radiation and miRNA extracellular vesicles expression levels was investigated in human astrocytes after treatment with 3 Gy proton radiation at Willis-Knighton Cancer Center. Microarray analysis was performed using miRNA from the EVs enriched fraction in the cell culture medium collected from sham-control and radiation-treated cells. The exosomal levels of 13 miRNAs were significantly (FDR p < 0.05) down-regulated after exposure to high-energy radiation. The computational analysis identified hsa-miR-762, hsa-let-7c-5p, and has-let-7b-5p regulate the highest number of genes being associated with cognitive, mental, and motor delay. These miRNAs target the same subset of genes (Amd1, CCNF, COX6B, PLXND1) that are associated with epileptic encephalopathy; frontotemporal dementia; mitochondrial complex iv deficiency, and a rare neurological condition (Moebius syndrome) respectively. GO enrichment analysis of the biological processes identified overrepresentation in mRNA polyadenylation and regulation of glutamine and long fatty acids transport. Gene expression analysis confirmed the upregulation of the glutamine synthetase after irradiation. Significant fold enrichment of GO l-glutamine transmembrane transporter activity was identified in the molecular function category as well indicating exosome-mediated regulation of this important pathway after proton radiation exposure.

Exploring the pathogenesis of type 2 diabetes mellitus intestinal damp-heat syndrome and the therapeutic effect of Gegen Qinlian Decoction from the perspective of exosomal miRNA

Ethnopharmacological relevanceDiabetes is a common, complex, chronic metabolic disease. A randomized, double-blind, placebo-parallel controlled clinical study has shown that Gegen Qinlian Decoction (GQD) can reduce glycosylated hemoglobin in type 2 diabetes mellitus (T2DM) intestinal damp-heat syndrome patients in a dose-dependent manner. AimTo explore the pathogenesis of T2DM intestinal damp-heat syndrome and the therapeutic effect of GQD from the perspective of exosomal microRNA (miRNA). MethodsEligible patients were selected and treated with GQD for 3 months to evaluate their clinical efficacy. Effective cases were matched with healthy volunteers, and saliva samples were collected. Exosomal miRNA was extracted from saliva and analyzed by chip sequencing. Subsequently, the function of the differential gene and the signal transduction pathway were analyzed using bioinformatics technology. Finally, three target miRNAs were randomly selected from the T2DM group/healthy group, and two target miRNAs in the T2DM before treatment/after treatment group were randomly selected for qPCR verification. Finally, we conducted a correlation analysis of the miRNAs and clinical indicators. The registration number for this research is ChiCTR-IOR-15006626. Results(1) The expression of exosomal miRNA chips showed that there were 14 differentially expressed miRNAs in the T2DM group/healthy group, and 26 differentially expressed miRNAs in the T2DM before treatment/after treatment group. (2) Enrichment results showed that in the T2DM group/healthy group, it was primarily related to cell development, body metabolism, TGF-β, and ErbB signaling pathways. In the T2DM before treatment/after treatment group, it was mainly related to cellular metabolic regulation processes, and insulin, Wnt, and AMPK signaling pathways. (3) The qPCR verification showed that the expressions of hsa-miR-9-5p, hsa-miR-150–5p, and hsa-miR-216b-5p in the T2DM group was higher (P<0.05). Following GQD treatment, hsa-miR-342–3p and hsa-miR-221–3p were significantly downregulated (P<0.05). (4) hsa-miR-9-5p was positively correlated with BMI (P<0.05), and hsa-miR-150–5p was positively correlated with total cholesterol and triglycerides (P<0.05). The GQD efficacy-related gene hsa-miR-342–3p was positively correlated with the patient's initial blood glucose level (P<0.05), and hsa-miR-221–3p was positively correlated with total cholesterol and triglycerides (P<0.05). ConclusionThe exosomal miRNA expression profile and signaling pathways related to T2DM intestinal damp-heat syndrome and the efficacy of GQD were established, which provides an alternative strategy for precision traditional Chinese medicine treatment.

A Dual Marker for Monitoring MDR-TB Treatment: Host-Derived miRNAs and M. tuberculosis-Derived RNA Sequences in Serum.

BackgroundIn the absence of a late marker of treatment failure or relapse in MDR-TB patients, biomarkers based on host-miRNAs coupled with M. tuberculosis-RNAs evaluated in extracellular vesicles (EVs) are an alternative follow-up for MDR-TB disease. Characterization of EVs cargo to identify differentially expressed miRNAs before and after treatment, and to identify M. tuberculosis-derived RNA in serum EVs from resistant TB patients.MethodsEVs were isolated from serum of 26 drug-resistant TB (DR-TB) patients and 16 healthy subjects. Differential expression of miRNAs in pooled exosomes from both untreated and treated patients was assessed and individually validated at different time points during treatment. In addition, M. tuberculosis RNA was amplified in the same samples by qPCR.ResultsA multivariate analysis using miR-let-7e-5p, -197-3p and -223-3p were found to be a more sensitive discriminator between healthy individuals and those with TB for both DR-TB (AUC= 0.96, 95%, CI=0.907-1) and MDR-TB groups (AUC= 0.95, 95%, CI= 0.89-1). Upregulation of miR-let-7e-5p were observed at the time of M. tuberculosis negative culture T(3-5) for MDR-TB group or for long-term T(9-15) for MDR-TB group without diabetes (T2DM). A second pathogen-based marker based on 30kDa and 5KST sequences was detected in 33% of the MDR-TB patients after the intensive phase of treatment. The miR-let7e-5p is a candidate biomarker for long-term monitoring of treatment for the group of MDR-TB without T2DM. A dual marker of host-derived miR-let7e-5p and M. tuberculosis-derived RNA for monitoring-TB treatment based in serum EVs.ConclusionA dual marker consisting of host-derived miR-let7e-5p and M. tuberculosis-derived RNA, could be an indicator of treatment failure or relapse time after treatment was completed.

Isolation and characterisation of graves’ disease-specific extracellular vesicles from tissue maintained on a bespoke microfluidic device

This report demonstrates the ability of a microfluidic device to maintain human Graves' disease tissue enabling the isolation and characterisation of Graves' disease specific exosomes. Graves' disease (n = 7) and non-Graves’ disease (Hashimoto's thyroiditis, n = 3; follicular adenoma, n = 1) human tissue was incubated in a microfluidic device for 6 days ± dexamethasone or methimazole and effluent was analysed for the size and concentration of extracellular vesicles (EV) using nanoparticle tracking analysis. Exosomes were isolated by centrifugation and characterised using Western blotting and qRT-PCR for miRNA-146a and miRNA-155, previously reported to be immunomodulatory. EV were detected in all effluent samples. No difference in concentration was observed in the EV released from Graves' compared to non-Graves’ disease tissue and although the size of EV from Graves' disease tissue was smaller compared to those from non-Graves’ disease tissue, the difference was not consistently significant. No effect of treatment was observed on the size or concentration of EV released. The exosome markers CD63 and CD81 were detectable in 2/5 Graves' disease tissue exosomes and CD63 was also evident in exosomes from a single non-Graves’ sample. miRNA-146a and miRNA-155 were detectable in all samples with no difference between tissue cohorts. Treatment did not influence miRNA expression in exosomes isolated from Graves' disease tissue. Although miRNA-146a and miRNA-155 were both elevated following treatment of non-Graves’ disease tissue with dexamethasone and methimazole, the increase was not significant. This study provides a proof of concept that incubation of tissue on a microfluidic device allows the detection, isolation and characterisation of extracellular vesicles from human tissue biopsies. • Use of microfluidic technology to maintain human tissue. • Collection and characterisation of tissue specific exosomes. • Determination of treatment effect on the release of extracellular vesicles.

Serum exosomal miRNAs profiling and functional study in patients with non-alcoholic fatty liver disease

Objective: Differential expression of serum exosomal miRNAs were detected for NAFLD patients and healthy controls, thereby determining the role of serum exosomal miRNAs in the pathogenesis, diagnosis, and treatment of NAFLD. Methods: Four patients with S2-3 NAFLD who shared similar demographic features and personal histories, and matched healthy controls were recruited for high-throughput sequencing of serum exosomal miRNAs. Four miRNAs with the most significant differential expression were verified by qRT-PCR in three groups (S1, S2-3, and control groups) with 20 cases in each group. Target gene prediction was performed for these differentially-expressed miRNAs, along with GO and KEGG enrichment analyses for the target genes. T-test or ANOVA were used for normally distributed data. Wilcoxon rank sum test was used for ranked data and non-normally distributed data. The count data used Pearson chi-square test or Fisher's exact test. Results: There were 19 serum exosomal miRNAs with significantly different levels of expression (P < 0.05) and a fold-change > 2. The expression of hsa-miR-122-5p, hsa-miR-146b-5p, and hsa-miR-197-3P was highest in the S2-3 group, followed by the S1 and control groups (in order); hsa-miR-483-3p expression was higher in the NAFLD group (S1 or S2-3) than the control group. There were 84 pathways significantly enriched in target genes. From 20 pathways closely related to NAFLD, at least 5 target genes which were simultaneously correlated to all 10 pathways were screened (PIK3R2, AKT2, AKT3, MAPK1, and NFKB1). Conclusion: Differential expression of serum exosomal miRNAs was detected in NAFLD patients and healthy controls. Four miRNAs with the greatest fold-changes were assessed to judge the severity of fatty degeneration of the liver. The research findings provide reference for non-invasive identification of new biomarkers and specific targets for NAFLD treatment.

Differential Expression of Serum Exosomal miRNAs in Breast Cancer Patients and Healthy Controls.

Purpose: Breast cancer has become as a serious public health concern worldwide. Breast cancer cells release exosomes into the circulatory system, which are easily accessible for further analysis like cancer diagnosis. In this study, we aimed to investigate expression of circulating exosomal miRNAs (miRs) in the serum of individuals with breast cancer and healthy controls. Methods: Exosomes were collected from serum samples using a commercial kit and characterized by scanning electron microscopy (SEM) and flow cytometry analysis. Expression of miRs such as miR-21, miR-155, miR-182, miR-373, and miR-126 were evaluated by real-time PCR. Results: The result showed that the expression level of exosomal miR-21, miR-155, miR-182, and miR-373 in the serum of breast cancer patients was higher than of those controls (P<0.05). However, expression of miR-126 did not change between breast cancer and control individuals (P > 0.05). Conclusion: Our results showed a different miRs expression pattern between breast cancer and healthy samples, supposing potential biomarkers for breast cancer. Further studies focusing on these miRs are required to confirm our findings.

P-077: Bone marrow microenvironment analysis of exosomal microRNAs in multiple myeloma, extramedullary disease and plasma cell leukemia

<h3>Background</h3> Multiple myeloma (MM) is a heterogeneous plasma cell (PC) malignancy. These malignant PC are dependent on the bone marrow (BM) microenvironment. However, a subclone of PCs can escape the BM microenvironment and infiltrate soft tissues and organs in the so-called extramedullary disease (EMD). This subclone may also escape to peripheral blood; if there are more than 20% of circulating PC (cPC), the disease is reclassified as plasma cell leukemia (PCL). All cells in the BM microenvironment release exosomes. Exosomes are small membranous vesicles that originate from internal multivesicular bodies; they are found in all body fluids, including peripheral blood, breast milk, etc. Exosomes are important in intercellular communication, and they have been implicated in disease relapse, resistance to chemotherapy and many other processes important for tumorigenesis. They contain proteins and nucleic acids, such as microRNAs (miRNAs) - short non-coding RNA molecules that are involved in many physiological and pathological processes. <h3>Aims</h3> The aim of this work was to analyze expression of exosomal miRNAs in BM plasma samples of MM, EMD and PCL patients. <h3>Methods</h3> Exosomes were isolated using qEV columns. MiRNAs were isolated from exosomes using qEV original Size Exclusion Columns, following miRNA isolation using miRNeasy Micro Kit. For next generation sequencing (NGS), 8 MM, 7 EMD and 8 PCL samples were used. Results from NGS were validated on 40 MM, 25 EMD and 21 PCL samples by RT-qPCR using Taqman Advanced MiRNA Assays. <h3>Results</h3> NGS analysis showed 1128 different miRNAs that were present in analyzed samples. Out of these, 239 miRNAs were found in at least 8 samples and had more than 1 read per million; thus, they were included in subsequent analysis. Out of these miRNAs, there are 6 miRNAs (p<0.05) that are significantly dysregulated between MM, EMD and PCL patients. Furthermore, 11 miRNAs (p<0.05) were significantly dysregulated between MM and EMD patients, 4 miRNAs (p<0.10) between MM and PCL patients and 7 miRNAs (p<0.05) between PCL and MM patients. We validated 6 miRNAs which were differentially expressed between MM, EMD and PCL. <h3>Conclusions</h3> Using NGS, we showed that they are differentially expressed exosomal miRNAs between MM, EMD and PCL patients suggesting their role in pathogenesis of these diseases. This work was supported by AZV 17-29343A and AZV 18-003-00203.

A Pilot Study of miRNA Expression Profile as a Liquid Biopsy for Full-Marathon Participants.

Exosomal microRNA (miRNA) in plasma and urine has attracted attention as a novel diagnostic tool for pathological conditions. However, the mechanisms of miRNA dynamics in the exercise physiology field are not well understood in terms of monitoring sports performance. This pilot study aimed to reveal the miRNA dynamics in urine and plasma of full-marathon participants. Plasma and urine samples were collected from 26 marathon participants before, immediately after, 2 h after, and one day after a full marathon. The samples were pooled, and exosomal miRNAs were extracted and analyzed using next-generation sequencing. We determined that the exosomal miRNA expression profile changed under time dependency in full marathon. New uncharacterized exosomal miRNAs such as hsa-miR-582-3p and hsa-miR-199a-3p could be potential biomarkers reflecting physical stress of full marathon in plasma and urine. In addition, some muscle miRNAs in plasma and urine have supported the utility for monitoring physical stress. Furthermore, some inflammation-related exosomal miRNAs were useful only in plasma. These results suggest that these exosomal miRNAs in plasma and/or urine are highly sensitive biomarkers for physical stress in full marathons. Thus, our findings may yield valuable insights into exercise physiology.

Expression, regulation, and function of exosome-derived miRNAs in cancer progression and therapy.

Exosomes are a novel class of intercellular signal modulators that contain a wide range of molecules and deliver information between cells and tissues. MicroRNAs (miRNAs), a type of regulatory non-coding RNA, are often incorporated into exosomes as signaling molecules. In this review, we discuss the expression of exosomal miRNAs from diverse origins such as tumor cells, solid tumor tissue, and biological fluids in various cancers (lung, breast, colorectal, liver, stomach, and pancreatic). We address the biological functions of exosome-derived miRNAs in processes such as tumor-cell proliferation, angiogenesis, metastasis, and chemoresistance in the tumor microenvironment. In particular, we discuss three oncogenic miRNAs, miR-21, miR-141, and miR-451, which occur within exosomes, in terms of gene regulation and intercellular communication. We consider therapeutic miRNA-based nanoparticles, which are widely expressed in tumors and show promise in drug therapy. The review assesses the wide-ranging evidence for using exosomal miRNAs as tumor markers in molecular diagnosis. Further, we consider the use of nanoparticle platforms to transport miRNAs, in the targeted treatment of disease and tumors.

Clinical impact of serum exosomal microRNA in liver fibrosis.

Background/aimWe investigated alterations in the expression of serum exosomal miRNAs with the progression of liver fibrosis and evaluated their clinical applicability as biomarkers.MethodsThis study prospectively enrolled 71 patients who underwent liver biopsy at an academic hospital in Korea. Exosomes were extracted from serum samples, followed by next-generation sequencing (NGS) of miRNAs and targeted real-time quantitative polymerase chain reaction. A model was derived to discriminate advanced fibrosis based on miRNA levels and the performance of this model was evaluated. Validation of the effect of miRNA on liver fibrosis in vitro was followed.ResultsNGS data revealed that exosomal miR-660-5p, miR-125a-5p, and miR-122 expression were changed significantly with the progression of liver fibrosis, of which miR-122 exhibited high read counts enough to be used as a biomarker. The level of exosomal miR-122 decreased as the pathologic fibrosis grade progressed and patients with biopsy-proven advanced fibrosis had significantly lower levels of exosomal miR-122 (P < 0.001) than those without advanced fibrosis. Exosomal miR-122 exhibited a fair performance in discriminating advanced fibrosis especially in combination with fibrosis-4 score and transient elastography. In a subgroup of patients with a non-viral etiology of liver disease, the performance of exosomal miR-122 as a biomarker was greatly improved. Inhibition of miR-122 expression increased the proliferation of the human hepatic stellate cell line, LX-2, and upregulated the expression of various fibrosis related proteins.ConclusionExosomal miR-122 may serve as a useful non-invasive biomarker for liver fibrosis, especially in patients with non-viral etiologies of chronic liver disease.

MicroRNAs sequencing of plasma exosomes derived from patients with atrial fibrillation: miR-124-3p promotes cardiac fibroblast activation and proliferation by regulating AXIN1.

MicroRNAs (miRNAs) play an important role in the pathogenesis of atrial fibrillation (AF). Exosomal miRNAs may develop as promising biomarkers for AF. To explore significant exosomal miRNAs in AF, plasma exosomes were extracted from 3 patients with AF and 3 patients with sinus rhythm (SR), respectively. Differential expression of exosomal miRNAs were screened by high-throughput sequencing analysis and verified by qRT-PCR from 40 patients with AF and 40 patients with SR. The target genes prediction, biological function, and signaling pathways analysis were conducted by miRanda software, gene ontology (GO), and KEGG analysis. The results showed that there were 40 differently expressed exosomal miRNAs from AF patients compared with SR patients, of which 13 miRNAs were upregulated and 27 miRNAs were downregulated. qRT-PCR validation demonstrated that miR-124-3p, miR-378d, miR-2110, and miR-3180-3p were remarkably upregulated, while miR-223-5p, miR-574-3p, miR-125a-3p, and miR-1299 were downregulated. To explore the function of miR-124-3p associated with AF, plasma exosomes derived from AF patients were co-incubated with rat myocardial fibroblasts. The expression of miR-124-3p was upregulated in myocardial fibroblasts. The viability and proliferation of myocardial fibroblasts were elevated by transfecting with miR-124-3p overexpression plasmids using CCK8 and immunofluorescence-staining methods. AXIN1 was verified to be the target of miR-124-3p by luciferase assay in vitro. Expression of AXIN1 was reduced, while β-catenin, Collagen 1, and α-SMA were increased in myocardial fibroblasts with miR-124-3p overexpression. In conclusion, these findings suggested that circulating exosomal miRNAs may serve as novel biomarkers for AF, and miR-124-3p promotes fibroblast activation and proliferation through regulating WNT/β-catenin signaling pathway via AXIN1.

Exosomal miR-214-3p as a potential novel biomarker for rhabdoid tumor of the kidney.

Rhabdoid tumor of the kidney (RTK) is a rare, highly aggressive pediatric renal tumor. No specific biomarkers are available for detection of RTK, and the initial differential diagnosis from other pediatric abdominal tumors, including neuroblastoma (NB), is difficult. Exosomal miRNAs are novel cancer biomarkers that can be detected in biological fluids. We explored candidate RTK-specific exosomal miRNAs as novel biomarkers of RTK. Exosomal miRNAs were collected from conditioned media of human RTK-derived cell lines, a human embryonic renal cell line, and human NB-derived cell lines. miRNA sequencing (miRNA-Seq) was performed to detect candidate RTK-specific exosomal miRNAs. The exosomal miRNA expression in conditioned media of tumor cell lines and serum from RTK xenograft-bearing mice was analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The expression of exosomal miR-214-3p detected by miRNA-Seq was highest in RTK-derived cell lines. Exosomal miR-214-3p expression level determined by qRT-PCR was significantly higher in RTK-derived cell lines than in the human embryonic renal cell line or NB-derived cell lines. Furthermore, the serum exosomal miR-214-3p expression level was significantly higher in RTK xenograft mice than controls. Our data indicated that exosomal miR-214-3p has potential as a novel biomarker of RTK.

MiR-3064 in Epicardial Adipose-Derived Exosomes Targets Neuronatin to Regulate Adipogenic Differentiation of Epicardial Adipose Stem Cells.

Backgroud: The metabolism of epicardial adipose tissue (EAT) is closely related to coronary atherosclerotic heart disease (CAHD), but the specific mechanism is not fully understood. In this study, we investigated the effects of EAT microenvironment on adipose metabolism from the viewpoint of EAT-derived exosomes and epicardial adipose stem cells (EASCs).Methods: EAT samples from CAHD patients and non-CAHD patients were collected to obtain exosomes via tissue culture. MiRNA sequencing was performed to analyze differences in miRNA expression in exosomes between groups. Luciferase reporter assay was then performed to verify the miRNA target gene. EAT was digested by collagenase to obtain EASCs, which were induced to mature adipocytes in vitro. Immunochemical staining and western blotting were performed to detect protein expression levels.Results: The results showed that CAHD patients had higher levels of EASCs in EAT, and no significant difference in the adipogenic differentiation ability of EASCs was observed between CAHD and non-CAHD patients in vitro. This indicates that the EAT microenvironment is a key factor affecting the adipogenic differentiation of EASCs. The EAT-derived exosomes from CAHD patients inhibited adipogenic differentiation of EASCs in vitro. Sequencing analysis showed that miR-3064-5p was highly expressed in EAT-derived exosomes in CAHD patients, and its inhibitor could improve the adipogenic differentiation of EASCs. Luciferase reporter assay results showed that the target gene of miR-3064-5p is neuronatin (Nnat). Nnat remained silent in EASCs and was less expressed in EAT of CAHD patients.Conclusion: Abovementioned results suggest that Nnat is the key to regulating the adipogenic differentiation of EASCs, and miR-3064-5p in EAT-derived exosomes can inhibit the expression of Nnat by targeting its mRNA, thereby affecting the adipogenic differentiation of EASCs.

Exosomal and non-exosomal miRNA expression levels in patients with HCV-related cirrhosis and liver cancer.

Patients with HCV-related cirrhosis are at risk for liver cancer development. For these patients miRNAs may serve as preclinical markers, which expression levels are deregulated in cancer and which are stable to the damaging factors partly through complex formation with proteins or packaging into exosomes. In this research we have tried to identify what miRNA fraction in plasma – exosomal or not packed into exosomes (non-exosomal) – is stronger associated with primary liver cancer. The second question was whether saliva miRNA expression levels – both exosomal and non-exosomal – are associated with primary liver cancer. We evaluated exosomal and non-exosomal miRNAs – let-7a-5p, -16-5p, -18a-5p, -21-5p, -22-3p, -34a-5p, -103a-3p, -122-5p, -221-3p, -222-3p – in plasma and saliva of patients with HCV-related liver cirrhosis (n = 24), primary liver cancer (n = 24) and healthy volunteers (n = 21). Relative expression level was calculated with normalization of exosomal miRNA to exosomal miRNA-16-5p, non-exosomal miRNA to non-exosomal miRNA-16-5p and as a ratio of exosomal miRNA to non-exosomal miRNA. In this study, non-exosomal miRNAs (let-7a, miRNA-21-5p, -22-3p, -103a, -122-5p, -221-3p and 222-3p) normalized to non-exosomal miRNA-16-5p showed strong association with liver cancer in plasma. Three miRNAs, those with the mostly pronounced change of expression levels in plasma, – miRNA-21-5p, 122-5p, 221-3p – were detected in saliva. In contrast, exosomal miRNAs show stronger association with primary liver over non-exosomal miRNAs when working with saliva. Thus, depending on the examined biological material both miRNA fractions may serve as a valuable source for diagnostic and prognostic data.

Analysis of serum microRNA in exosomal vehicles of papillary thyroid cancer.

In this study, we investigated the profile of microRNAs (miRNAs) contained in exosomes secreted in the serum of patients with papillary thyroid cancer (PTC). Exosome were isolated by adding ExoQuick Exosome Precipitation Solution. Dynamic light scattering (DLS) and western blotting analysis were used to ensure the quality of exosomes. The expression levels of miRNAs were investigated using custom-designed TaqMan Advanced miRNA Array Cards in the screening cohort and using specific TaqMan Advanced MicroRNA Assays in the validation cohort. We identified miR24-3p, miR146a-5p, miR181a-5p and miR382-5p with different expression levels in two different series of 56 and 58 PTC patients as compared with healthy controls. Significant differences in the expression of three PTC exosomal miRNAs, depending on the presence of lymph node metastasis, were detected in only one PTC series. When comparing the expression levels of some PTC-specific exosomal miRNAs with those of the same miRNAs circulating free of any encapsulation, we found a significant correlation for only miR24-3p, suggesting that only select miRNAs are secreted in exosomes. Our findings demonstrate that four miRNAs are differently secreted in the exosomes of PTC patients, whereas no conclusive results were found to characterize PTCs with lymph node metastasis, suggesting caution in the use of circulating exosomal miRNA expression levels as lymph node metastasis biomarkers. Further investigation into the mechanisms governing miRNA secretion in tumor cells are required.

Evaluation of the severity of nonalcoholic fatty liver disease through analysis of serum exosomal miRNA expression.

Noninvasive techniques for evaluating the severity of nonalcoholic fatty liver disease (NAFLD) have shown limited diagnostic performance. MicroRNAs (miRNAs) are useful biomarkers for diagnosing and monitoring the progression and treatment response to several diseases. Here, we evaluated whether serum exosomal miRNAs could be used for the diagnosis and prognosis of NAFLD severity. Exosomal miRNAs were isolated from the sera of 41 patients with NAFLD (diagnosed using liver biopsy) for microarray profiling. The degree of NAFLD severity was determined using inflammation, steatosis, and ballooning scores and the NAFLD activity score (NAS). Correlations between miRNA expression, clinical and biochemical parameters, and mRNA expression were analyzed. Overall, 25, 11, 13, and 14 miRNAs correlated with the inflammation score, steatosis score, ballooning score, and NAS, respectively, with 33 significant correlations observed between 27 miRNAs and six clinical variables. Eight miRNAs (let-7b-5p, miR-378h, -1184, -3613-3p, -877-5p, -602, -133b, and 509-3p) showed anticorrelated patterns with the corresponding mRNA expression. In fibrosis, 52 and 30 interactions corresponding to high miRNA-low mRNA and low miRNA-high mRNA expression, respectively, were observed. The present results therefore suggest that serum exosomal miRNAs can be used to evaluate NAFLD severity and identify potential targets for NAFLD treatment.