Plasma miR-21 Research Articles

Association of tumor and plasma microRNA expression with tumor monosomy-3 in patients with uveal melanoma.

BackgroundEpigenetic events mediated by methylation and histone modifications have been associated with the development of metastasis in patients with uveal melanoma. The role of epigenetic events mediated by microRNA (miR) is less clear. Tumor and plasma miR expression was examined in patients with primary uveal melanoma with tumor monosomy-3, a predictor of metastasis.ResultsmiR profiling of tumors by microarray found six miRs over-expressed and 19 under-expressed in 33 tumors with monosomy-3 compared to 22 without. None of the miRs differentially expressed in tumors with and without monosomy-3 was differentially expressed in tumors with and without tumor infiltrating lymphocytes. Tumors manifesting monosomy-3 were also characterized by higher levels of TARBP2 and DDX17 and by lower levels of XPO5 and HIWI, miR biogenesis factors. miR profiling of plasma by a quantitative nuclease protection assay found elevated levels of 11 miRs and reduction in four in patients with tumor monosomy-3. Only three miRs differentially expressed in the tumor arrays were detectable in plasma. miRs implicated in uveal melanoma development were not differentially expressed. Elevated plasma levels in patients with tumor monosomy-3 of miR-92b, identified in the tumor array, and of miR-199-5p and miR-223, identified in the plasma array, were confirmed by quantitative real-time polymerase chain reaction. Levels were also higher in patients compared to normal controls.ConclusionsThese results support a role for epigenetic mechanisms in the development of metastasis in patients with uveal melanoma and the analysis of miRs as biomarkers of metastatic risk. They also suggest that potentially useful blood miRs may be derived from the host response as well as the tumor.

The role of microRNA-155, microRNA-222 and mitogen-activated protein kinase signaling pathway in ventricular septal defect

Objective To explore the expression and clinical significance of microRNA(miR)-155 and miR-222 in plasma of patients with ventricular septal defect(VSD), and to analyze the possible mechanism. Methods A total of 20 children with VSD who received treatment at the Department of Cardiovascular Surgery from August 2012 to June 2013 were enrolled (the VSD group) and 15 patients with fracture (the control group). The plasma miR-155 and miR-222 expression levels were measured by real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The potential target genes of miR-155 and miR-222 were predicted by using 3 currently available prediction programs, including TargetScan, mirbase and Miranda, and the signaling pathway of miRNA was predicted by Pathway-express analysis. Results Compared with the control group, the expression levels of miR-155(P=0.033) and miR-222(P<0.001) in the VSD group decreased significantly; miR-155 and miR-222 predicted target genes included 74 and 50, respectively.The Pathway-express analysis indicated that 7 signaling pathways played important roles in the occurrence of fetal VSD, including signaling pathways for heart development, such as: mitogen-activated protein kinase(MAPK) signaling pathway. Conclusions The expression levels of plasma miR-155 and miR-222 in VSD were significantly decreased.The target genes were related to signaling pathways for heart deve-lopment (MAPK signaling pathway), which indicates that miR-155 and miR-222 may be involved in the pathological process of VSD, and may serve as an independent evaluation indicator for the diagnosis of VSD. Key words: microRNA; Ventricular septal defect; Mitogen-activated protein kinase signaling pathway

MicroRNA-21 is associated with fibrosis in a rat model of nonalcoholic steatohepatitis and serves as a plasma biomarker for fibrotic liver disease.

Evidence indicates that hepatic fibrosis is the initial lesion of cirrhosis or hepatocellular carcinoma in diseases such as nonalcoholic steatohepatitis (NASH). To induce NASH, we fed rats a choline-deficient and iron-supplemented L-amino acid-defined (CDAA) diet. Histopathological examination revealed that fibrosis appeared from week 4 and progressed to bridging fibrosis from week 12. Using qRT-PCR assays, we detected increased expression of miR-21, Mmp-9, and Timp-1 in liver that peaked during week 4, when fibrosis was first detected. The expression pattern of miR-21 in plasma paralleled that in liver. Fibrosis tended to be resolved within 12 weeks of a recovery period after 12 weeks of feeding, and the expression of miR-21, Timp-1, and Mmp-9 decreased in liver. Comprehensive analyses of miRNA and mRNA expression in the liver using samples acquired at week 4 detected 16 miRNAs and 11 mRNAs that are mutually-interacting fibrosis-related factors. We therefore conclude that miR-21 was closely associated with fibrosis in a rat model of NASH and has potential as a plasma biomarker for hepatic fibrosis.

A ZEB1-miR-375-YAP1 pathway regulates epithelial plasticity in prostate cancer.

MicroRNA-375 (miR-375) is frequently elevated in prostate tumors and cell-free fractions of patient blood, but its role in genesis and progression of prostate cancer is poorly understood. In this study, we demonstrated that miR-375 is inversely correlated with epithelial-mesenchymal transition signatures (EMT) in clinical samples and can drive mesenchymal-epithelial transition (MET) in model systems. Indeed, miR-375 potently inhibited invasion and migration of multiple prostate cancer lines. The transcription factor YAP1 was found to be a direct target of miR-375 in prostate cancer. Knockdown of YAP1 phenocopied miR-375 overexpression, and overexpression of YAP1 rescued anti-invasive effects mediated by miR-375. Furthermore, transcription of the miR-375 gene was shown to be directly repressed by the EMT transcription factor, ZEB1. Analysis of multiple patient cohorts provided evidence for this ZEB1-miR-375-YAP1 regulatory circuit in clinical samples. Despite its anti-invasive and anti-EMT capacities, plasma miR-375 was found to be correlated with circulating tumor cells in men with metastatic disease. Collectively, this study provides new insight into the function of miR-375 in prostate cancer, and more broadly identifies a novel pathway controlling epithelial plasticity and tumor cell invasion in this disease.

Elevated levels of miR-210 correlate with anemia in β-thalassemia/HbE patients.

Ineffective erythropoiesis in β-thalassemia patients is caused by the premature death of red blood cell precursors due to excess α-globin chains. As a consequence, patients develop chronic anemia and hypoxia. Upregulation of miR-210, a hypoxia-induced miRNA, has been shown to regulate globin gene expression and erythroid differentiation in β-thalassemia/HbE erythroid progenitor cell culture. The present study examined whether the expression of miR-210 in circulation reflects the anemic condition in these patients. The level of miR-210 expression was directly examined from red blood cells and plasma of β-thalassemia/HbE patients. Transferrin receptor, a marker of erythropoiesis activity, was also analyzed. Increased expression of both red blood cells and plasma miR-210 as well as elevated levels of serum transferrin receptor in β-thalassemia/HbE patients were observed when compared to those of normal individuals (p<0.05). In addition, red blood cell miR-210 level was inversely correlated with hemoglobin levels (r=-0.7054, p<0.01) and hematocrit (r=-0.6017, p<0.05). The higher expression of miR-210 in these patients may be the consequence of hypoxia occurring from the lower hemoglobin level. Thus, analysis of red blood cell miR-210 may be useful as a method for assessing hypoxia in β-thalassemia patients.

Abstract 26: Low Plasma Mir-155 Levels and RhoA Activation Correlates with Small AAA Expansion

Introduction: Given increased abdominal imaging studies, the incidental diagnosis and treatment of small AAAs is problematic. Presently, no specific recommendations for medical management can be made other than serial observation. The ras homolog member A (RhoA) signaling cascade is implicated in vascular diseases due to its ability to modulate monocyte endothelial invasion. We sought to investigate the RhoA signaling pathway in AAA expansion, along with an endogenous inhibitor of RhoA, microRNA-155 (miR-155). Hypothesis: We hypothesize that RhoA is activated to enable AAA expansion, but once expanded, miR-155 is called on to inhibit RhoA activation so that the expanded AAA can be stabilized. Methods: Peripheral blood was collected for monocyte and plasma isolation from stable AAA (&lt; 0.1 cm/year) (n=9) and expanding AAA (≥ 0.1 cm/year) (n=10) patients. Rhotekin-RBD assay and western blots were used to assess relative Rho-GTP expression and quantitative PCR for miR-155 detection in blood plasma. T-test and χ2 analysis were used to determine statistical significance. Results: Given limited monocytes, 6 stable and 10 expanding AAA patients were identified for RhoA analysis. Monocytes from expanding AAA patients contained higher active Rho-GTP protein levels compared to stable AAA monocytes (Figure 1a: 1.60±.075 vs 1.20±.088, ρ=.0004). Plasma concentrations of miR-155 were significantly lower in expanding AAA plasma compared to stable AAAs (Figure 1b: -2.17±.95, P=.005). Conclusions: Expanding AAA patients have greater monocyte activation of RhoA and decreased plasma expression of miR-155, when compared to stable AAA patients. The RhoA signaling pathway has altered activation in AAA disease and its regulation may reduce expansion rates and inflammation.

Coronary Artery-Bypass-Graft Surgery Increases the Plasma Concentration of Exosomes Carrying a Cargo of Cardiac MicroRNAs: An Example of Exosome Trafficking Out of the Human Heart with Potential for Cardiac Biomarker Discovery.

IntroductionExosome nanoparticles carry a composite cargo, including microRNAs (miRs). Cultured cardiovascular cells release miR-containing exosomes. The exosomal trafficking of miRNAs from the heart is largely unexplored. Working on clinical samples from coronary-artery by-pass graft (CABG) surgery, we investigated if: 1) exosomes containing cardiac miRs and hence putatively released by cardiac cells increase in the circulation after surgery; 2) circulating exosomes and exosomal cardiac miRs correlate with cardiac troponin (cTn), the current “gold standard” surrogate biomarker of myocardial damage.Methods and ResultsThe concentration of exosome-sized nanoparticles was determined in serial plasma samples. Cardiac-expressed (miR-1, miR-24, miR-133a/b, miR-208a/b, miR-210), non-cardiovascular (miR-122) and quality control miRs were measured in whole plasma and in plasma exosomes. Linear regression analyses were employed to establish the extent to which the circulating individual miRs, exosomes and exosomal cardiac miR correlated with cTn-I. Cardiac-expressed miRs and the nanoparticle number increased in the plasma on completion of surgery for up to 48 hours. The exosomal concentration of cardiac miRs also increased after CABG. Cardiac miRs in the whole plasma did not correlate significantly with cTn-I. By contrast cTn-I was positively correlated with the plasma exosome level and the exosomal cardiac miRs.ConclusionsThe plasma concentrations of exosomes and their cargo of cardiac miRs increased in patients undergoing CABG and were positively correlated with hs-cTnI. These data provide evidence that CABG induces the trafficking of exosomes from the heart to the peripheral circulation. Future studies are necessary to investigate the potential of circulating exosomes as clinical biomarkers in cardiac patients.

Extracellular microRNA-21 and microRNA-26a increase in body fluids from rats with antigen induced pulmonary inflammation and children with recurrent wheezing.

BackgroundThis study aims to find out whether extracellular miRNAs is implicated in recurrent childhood wheezing with asthmatic risk.MethodsOne hundred and forty children of Chinese Han population were recruited for this study. Plasma and intracellular miRNAs from children with recurrent wheezing and rats with antigen induced pulmonary inflammation (AIPI) were detected by using reverse transcription-quantitative PCR. Differential leukocytes in blood were automatically counted. Total IgE was detected by enzyme-linked immunosorbent assay. Clinical implication in diagnosis was evaluated using receiver operating characteristic curves.ResultsThe increase of plasma miR-21 and miR-26a was screened out from 11 candidate miRNAs and validated in wheezing children. The level of expression for both miRNAs were comparable in different age and gender. Plasma miR-21 was more preferable to miR-26a and total IgE for diagnosis. Plasma miR-21 and miR-26a levels were not significantly correlated with various leukocyte counts or miRNA expression in blood cells. In acute and chronic AIPI rats, miR-21 levels increased in both plasma and lavaged lung compared with control. Moreover, circulating miR-21 and miR-26a levels were highly positively correlated with infiltrated cell counts in bronchoalveolar lavage fluid of AIPI rats.ConclusionsCirculating miR-21 and miR-26a increase in wheezing children and AIPI rats. This not only manifests their strong clinical implication in recurrent childhood wheezing with asthma risk, but also provides novel insights into the role of extracellular miRNAs during development of airway inflammation and recurrent wheezing.Electronic supplementary materialThe online version of this article (doi:10.1186/s12890-016-0216-2) contains supplementary material, which is available to authorized users.

Droplet digital PCR and qRT-PCR to detect circulating miR-21 in laryngeal squamous cell carcinoma and pre-malignant laryngeal lesions

Conclusions: The present study indicates that miR-21 is involved in progression from normal to pre-malignant laryngeal lesions (PLLs) and from PLLs to laryngeal squamous cell carcinoma (LSCC). Furthermore, normalized PCR results for miR-21 might be used to discriminate between normal and ordinary hyperplasia before the emergence of dysplasias and pre-malignant lesions with malignant potential. Objective: To investigate a sensitive marker that contributes to progression from normal tissue to PLLs and from PLLs to LSCC. Methods: In 116 PLLs and LSCC patients and 19 without dysplasia matched sets of tissue and plasma samples from Beijing Tongren Hospital, miR-21 was analysed by droplet digital PCR and quantitative real-time polymerase chain reaction based on paraffin-embedded tumour tissue and plasma. Results: Compared with controls, miR-21 levels in tissue and plasma were significantly higher for both PLL and LSCC groups (for both groups vs controls: p < 0.0001 for tissue; p < 0.05 for plasma). Areas under receiver-operating curves (AUC) for tissue miR-21 were PLL group vs controls: 0.9026 and LSCC group vs controls: 0.8681. For plasma miR-21, AUCs were PLL group vs controls: 0.7355 and LSCC group vs control: 0.6723.

Tailoring Conformation-Induced Chromism of Polythiophene Copolymers for Nucleic Acid Assay at Resource Limited Settings

Here we report on the design and synthesis of cationic water-soluble thiophene copolymers as reporters for colorimetric detection of microRNA (miRNA) in human plasma. Poly(3-alkoxythiophene) (PT) polyelectrolytes with controlled ratios of pendant groups such as triethylamine/1-methyl imidazole were synthesized for optimizing interaction with target miRNA sequence (Tseq). Incorporation of specific peptide nucleic acid (PNA) sequences with the cationic polythiophenes yielded distinguishable responses upon formation of fluorescent PT-PNA-Tseq triplex and weakly fluorescent PT-Tseq duplex, thereby enabling selective detection of target miRNA. Unlike homopolymers of PT (hPT), experimental results indicate the possibility of utilizing copolymers of PT (cPT) with appropriate ratios of pendant groups for miRNA assay in complex matrices such as plasma. As an illustration, colorimetric responses were obtained for lung cancer associated miRNA sequence (mir21) in human plasma, with a detection limit of 10 nM, illustrating the feasibility of proposed methodology for clinical applications without involving sophisticated instrumentation. The described methodology therefore possesses high potential for low-cost nucleic acid assays in resource-limited settings.

Expression of plasma microRNA-223 (miR-223) in pediatric severe pneumonia patients and its relationship with severe pneumonia

Objective To investigate the changes of plasma microRNA-223 (miR-223) in pediatric severe pneumonia patients and its relationship with severe pneumonia. Methods There were 50 children with severe pneumonia enrolled in the study (observation group), and 50 healthy children were selected as control group (normal control group). The expression levels of plasma miR-223 were detected by real time polymerase chain reaction.The relationship between miR-223 and procalcitonin (PCT), C-reactive protein (CRP), tumor necrosis factor-α (TNF)-α, and interleukin (IL)-10 were analyzed. The predictive value of miR-223 in plasma, PCT, and CRP to severe pneumonia was evaluated by receiver operating characteristic (ROC) curve. The relationship between miR-223, T cells, TNF-α, and IL-10 was analyzed. Results The plasma miR-223 expression levels in observation group were upregulated compared to those in the normal control group[(16.01±5.17)×10-4 mg/L vs (5.44±2.21)×10-4 mg/L, t=7.46, P<0.01]. The CRP and PCT expression levels in severe pneumonia patients were higher than those of the normal control group[z=5.496, 5.198, P<0.05, or P<0.01]. The expressions of CD4+ CD25+ Treg, miR-223, and IL-10 in observation group were higher than those of normal control group (P<0.05). The expression of CD4+ CD25+ Treg, miR-223, and IL-10 in the death children were higher. There was a positive correlation between miR-223 and IL-10 (r=0.335, 0.571, P<0.01). The sensitivity and specific degrees to predict the severe pneumonia in mir-223, PCT, and CRP were 83.79%, 86.12%, 66.68%, 91.05%, 78.01%, and 44.23%, respectively. miR-223 was better than PCT and CRP to predict severe pneumonia in children. Conclusions The expression levels of plasma miR-223 in children with severe pneumonia could reflect the immunity, and it can be used as early prognostic markers to reflect the severity of inflammation in some degree. Key words: MicroRNAs/ME; Pneumonia/ME; Prognosis

Relationship between local production of microRNA-328 and atrial substrate remodeling in atrial fibrillation

BackgroundThe underlying mechanism of atrial substrate remodeling in atrial fibrillation (AF) remains unknown. In this study, we investigated whether local and systemic levels of microRNA (miR) might be associated with the presence of AF and with left atrial (LA) substrate properties. MethodsBlood from the periphery, pulmonary vein (PV), and left atrial appendage (LAA) was sampled from 30 patients with AF undergoing PV isolation, and from 10 control subjects with Wolff-Parkinson-White syndrome and without AF. We measured peripheral, PV, and LAA plasma levels of miR-1, -26, -133a, -328, and -590 by reverse transcription-polymerase chain reaction. LA global contact mapping during sinus rhythm was performed before PV isolation. ResultsPlasma levels of miR-328 were higher in patients with AF than in control subjects. Plasma miR-328 levels were significantly higher in the LAA than in the periphery and PV in patients with AF, but not in control subjects. Plasma miR-1 levels were also higher in the LAA than in the PV in AF patients. Interestingly, LAA plasma levels of miR-328 showed a positive correlation with the LA voltage zone index (area with voltage <0.5mV divided by total LA surface area) and a weak correlation with LA volume. ConclusionLocal production of miR-328 in the left atrium may be involved in the process of atrial remodeling in patients with AF.

Plasma miR-124-3p and miR-16 concentrations as prognostic markers in acute stroke

ObjectivesThis study aimed to investigate plasma concentrations of miR-124-3p and miR-16 as prognostic markers in emergency department patients with acute stroke. Design and methodsPlasma concentrations of miR-124-3p and miR-16 of 84 stroke patients (presenting to the emergency department within 24h from onset of symptoms) were determined by RT-qPCR. The primary outcome measure was 3-month mortality and the secondary outcome measure was post-stroke modified Rankin Score (mRS). ResultsTwelve patients (14.3%) died within 3months of hospital admission and forty-one (48.8%) patients as achieved a 3-month mRS>2. Median plasma miR-124-3p concentrations were elevated in patients who died compared to patients who survived (p=0.0052), and its levels were found to be higher in patients with a 3-month mRS>2 compared with patients with mRS≤2 (p=0.0312). Higher plasma miR-16 concentrations were observed in patients who survived than in patients who died (p=0.0394), while its concentrations were lower in patients achieving mRS>2 than in patients with mRS≤2 (p=0.0124). For a subgroup of cases presenting to the emergency department within 6h from time of symptom onset (n=36), plasma miR-124-3p concentrations predicted 3-month mortality with an area under the ROC curve of 0.87 (95%CI: 0.72–0.96). ConclusionsPlasma miR-124-3p and miR-16 are molecular markers which could be useful for the early prediction of mortality and mRS.

Plasma micro-RNA profiles in patients with major depressive disorder (MDD)

IntroductionMicro-RNAs (miRs) are involved in processes associated with MDD such as neural plasticity, neurogenesis, synaptogenesis and stress response. MiRs are detectable in biological fluids; however, no data is available regarding the use of plasma circulating miRs as markers of MDD, only whole blood or serum being reported so far.ObjectivesWe investigated plasma miR profiles as potential markers for MDD in patients treated with antidepressants.AimsTo detect and characterize differentially expressed miRs in the plasma of MDD patients, before and after treatment with escitalopram.MethodsBlood was collected from patients with MDD before and after 12 weeks of treatment. Plasma profiles of 1008 miRs were measured by real time PCR. The fold change of expression between time points was calculated and a paired t test was used for statistical significance. Gene targets and pathways were assessed in miRWalk2.0.ResultsFrom 222 plasma miRs expressed, 40 were significantly different after treatment. Upregulated miRs (23) belonged to 43 pathways, down-regulated miRs (17) belonged to 46 pathways; the top 5 significant pathways identified being pathways in cancer, Wnt signalling, endocytosis, axon guidance and MAPK signalling. Six of these miRs are common to all five pathways: miR-146a-5p, miR-146b-5p, miR-221-3p, miR-24-3p, miR-26a-5p.ConclusionsOur analysis of significant changes in plasma miRs after escitalopram treatment of MDD might open new avenues for the understanding of its mode of action and its side effects. To our knowledge, this is the first study to assess miRs affected by antidepressant treatment in plasma of MDD patients.Disclosure of interestThe authors have not supplied their declaration of competing interest.

The Prognostic Value of Plasma MicroRNA-155 and MicroRNA-146a Level in Severe Sepsis and Sepsis-Induced Acute Lung Injury Patients.

Sepsis induced acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are lifethreatening disorders. Acute Physiology and Chronic Health Evaluation (APACHE) scores and several plasma biological markers have been identified to predict the death or treatment outcome of sepsis induced ALI. Immune related microRNAs also have the potential as biomarkers to monitor this kind of disease. A total of 44 patients with severe sepsis, 102 patients with sepsis, and 19 healthy volunteers were enrolled in this study. Plasma miR-155 and miR-146a were determined by qRT-PCR. Genotyping analysis of miR146a rs2690164 was performed using PCR-restriction fragment length polymorphism assay. The relative plasma miR-155 and miR-146a concentrations were significantly increased in severe sepsis and sepsis-induced cases of ALI, compared with control subjects. The AUC of miR-155 and miR-146a for predicting 30-day mortality in ALI patients was 0.782 (95% CI 0.694 - 0.870) and 0.733 (95% CI 0.640 - 0.827), respectively. CC genotype of miR-146a rs2910164 was associated with worse treatment outcome of these patients. The current study provides evidence that the plasma miR-155 and miR-146a could be novel biomarkers for predicting the mortality and treatment outcome of sever sepsis and sepsis-induced acute lung injury.

Evaluation of Plasma miR-21 and miR-152 as Diagnostic Biomarkers for Common Types of Human Cancers

Stable blood based miRNA species have allowed for the differentiation of patients with various types of cancer. Therefore, specific blood-based miRNA might be considered as a methodology which could be informative of the presence of cancer potentially from multiple distinct organ sites. Recently, miR-21 has been identified as an “oncomir” in various tumors while miR-152 as a tumor suppressor. In this study, we investigated whether circulating miR-21 and miR-152 can be used for early detection of lung cancer (LuCa), colorectal carcinoma (CRC), breast cancer (BrCa) and prostate cancer (PCa), with distinguishing cancer from various benign lesions on these organ sites. We measured the two miRNA levels by using real-time RT-PCR in plasma samples from a total of 204 cancer patients, 159 various benign lesions, and 228 normal subjects. We observed significantly elevated expression of miR-21 and miR-152 in LuCa, CRC, and BrCa when compared with normal controls. We also found upregulation of plasma miR-21 and miR-152 levels in patients with benign lesions of lung and breast, as compared to normal controls, respectively. No significant expression variation of the two miRNAs was observed in PCa or prostatic benign lesions as compared to healthy controls. Receiver operating characteristic (ROC) analyses revealed that miR-21 and/or miR-152 can discriminate LuCa, CRC and BrCa from normal controls. Our results suggest that plasma miR-21 and miR-152 may serve as non-specific noninvasive biomarkers for early screening of LuCa, CRC, and BrCa, but not PCa.

Inflammation Related MicroRNAs Are Modulated in Total Plasma and in Extracellular Vesicles from Rats with Chronic Ingestion of Sucrose.

Circulating microRNAs (miRNAs) and the functional implications of miRNAs contained in extracellular vesicles (EVs) have gained attention in the last decade. Little is known about the regulation of the abundance of plasma miRNAs in response to chronic ingestion of carbohydrates. Therefore, we explored the circulating levels of miR-21, miR-146a, miR-155, and miR-223 in rats consuming sucrose in drinking water. Weanling Wistar rats were 25 weeks with 30% sucrose in drinking water, and miRNAs expression was determined in total plasma and in microvesicles, by RT-qPCR with TaqMan probe based assays for miR-21, miR-146a, miR-155, and miR-223, using cel-miR-39 (as spike in control and reference). Endotoxemia was also measured. Sucrose-fed animals showed higher body weight and retroperitoneal adipose tissue as well as higher glucose and triglyceride plasma levels than controls. Plasma endotoxin levels were low and not different among groups. Plasma miR-21 and miR-223 were higher in the sucrose group (p < 0.05), whereas miR-155 tended to be lower (p = 0.0661), and miR-146a did not show significant differences. In the plasma EVs the same trend was found except for miR-146a that showed significantly higher levels (p < 0.05). Overall, our results show that high carbohydrate ingestion modulates circulating miRNAs levels related to an inflammatory response.

Evaluation of miR-122 level in the plasma of chronically HCV infected patients

MicroRNAs (miRNAs) are small non-coding RNA molecules, which have an important function in regulating RNA stability and gene expression. They also can circulate in a cell-free form in the blood thatmakes them potential disease markers. The liver contains various classes of miRNAs in which miR-122 accounts for about 70% of all miRNAs and it has been proved that its level increases in case of liver damage. Here, we investigated plasma levels of miR-122 as a useful disease parameter in patients with chronic hepatitis C (CHC) infection. Thirty five hemophilia and thalassemia patients with CHC were studied. The total RNA was extracted from plasma samples, and miR-122 levels were measured by qPCR and then compared with the specific liver markers. The plasma levels of alanine transaminase (ALT) and aspartate transaminase(AST) were correlated with plasma miR-122 level in CHC patients, and the level of circulating miR-122 in healthy individual groups were rarely lower than those of patients with CHC. In our study, miR-122 levels correlated well with markers of liver inflammatory activity. Plasma miR-122 can be assumed to be another marker in liver similar to the currently used specific markers such as ALT and AST for evaluation of liver damage in hepatitis C virus (HCV) infected patients. Moreover, the correlation between miR-122 and ALT was shown to be higher than between miR-122 and AST.

Inhibition of miR-155 Protects Against LPS-induced Cardiac Dysfunction and Apoptosis in Mice.

Sepsis-induced myocardial dysfunction represents a major cause of death in intensive care units. Dysregulated microRNAs (miR)-155 has been implicated in multiple cardiovascular diseases and miR-155 can be induced by lipopolysaccharide (LPS). However, the role of miR-155 in LPS-induced cardiac dysfunction is unclear. Septic cardiac dysfunction in mice was induced by intraperitoneal injection of LPS (5 mg/kg) and miR-155 was found to be significantly increased in heart challenged with LPS. Pharmacological inhibition of miR-155 using antagomiR improved cardiac function and suppressed cardiac apoptosis induced by LPS in mice as determined by echocardiography, terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) assay, and Western blot for Bax and Bcl-2, while overexpression of miR-155 using agomiR had inverse effects. Pea15a was identified as a target gene of miR-155, mediating its effects in controlling apoptosis of cardiomyocytes as evidenced by luciferase reporter assays, quantitative real time-polymerase chain reaction, Western blot, and TUNEL staining. Noteworthy, miR-155 was also found to be upregulated in the plasma of patients with septic cardiac dysfunction compared to sepsis patients without cardiac dysfunction, indicating a potential clinical relevance of miR-155. The receiver-operator characteristic curve indicated that plasma miR-155 might be a biomarker for sepsis patients developing cardiac dysfunction. Therefore, inhibition of miR-155 represents a novel therapy for septic myocardial dysfunction.

The Expression of MicroRNA-155 in Plasma and Tissue Is Matched in Human Laryngeal Squamous Cell Carcinoma.

PurposeTumor-associated microRNAs have been detected in cancer, though whether plasma microRNA-155 (miR-155) could be a potential biomarker for laryngeal squamous cell carcinoma (LSCC) prognosis is unclear. We aimed to determine how miR-155 can be used to predict the clinical characteristics of patients with LSCC and correctly diagnose them.Materials and MethodsWe collected tissue samples and peripheral blood samples before and after treatment from 280 LSCC cases and 560 controls. Real-time quantitative reverse transcription PCR was employed in this study to compare the relative expression of miR-155.ResultsA total of 280 LSCC patients and 560 age- and sex-matched controls were included in the study. The miR-155 level was more up-regulated in LSCC tissue than in the non-tumor tissues (13.6±2.4 vs. 3.1±0.80, p<0.001). Additionally, a significantly higher miR-155 level in plasma samples from LSCC patients than in those of the controls (8.9±1.25 vs. 1.8±0.8, p<0.001) was reported. Tissue miR-155 showed an area under the curve (AUC) of 0.933, with a sensitivity of 82.6% and a specificity of 89.2%. The AUC for plasma miR-155 was 0.757, with a sensitivity of 58.4% and a specificity of 69.5%. When early LSCC in TNM I stage was considered, tissue miR-155 showed an area under the curve of 0.804, with a sensitivity of 85.2% and a specificity of 87.3%.ConclusionThe expression of tissue and plasma miR-155 were significantly up-regulated in patients with LSCC. Our work will serve as a basis for further investigation, preferably large-scale validation in clinical trials.