MicroRNA Expression in Myocardial Tissue and Plasma of Patients with End-Stage Heart Failure during LVAD Support: Comparison of Continuous and Pulsatile Devices

Aim

Pulsatile flow left ventricular assist devices (pf-LVADs) are being replaced by continuous flow LVADs (cf-LVADs) in patients with end-stage heart failure (HF). MicroRNAs (miRs) play an important role in the onset and progression of HF. Our aim was to analyze cardiac miR expression patterns associated with each type of device, to analyze differences in the regulation of the induced cardiac changes.

Methods and Results

Twenty-six miRs were selected (based on micro-array data and literature studies) and validated in myocardial tissue before and after pf- (n = 17) and cf-LVAD (n = 17) support. Of these, 5 miRs displayed a similar expression pattern among the devices (miR-129*, miR-146a, miR-155, miR-221, miR-222), whereas others only changed significantly during pf-LVAD (miR-let-7i, miR-21, miR-378, miR-378*) or cf-LVAD support (miR-137). In addition, 4 miRs were investigated in plasma of cf-LVAD supported patients (n = 18) and healthy controls (n = 10). Circulating miR-21 decreased at 1, 3, and 6 months after LVAD implantation. MiR-146a, miR-221 and miR-222 showed a fluctuating time pattern post-LVAD.

Conclusion

Our data show a different miR expression pattern after LVAD support, suggesting that differentially expressed miRs are partially responsible for the cardiac morphological and functional changes observed after support. However, the miR expression patterns do not seem to significantly differ between pf- and cf-LVAD implying that most cardiac changes or clinical outcomes specific to each device do not relate to differences in miR expression levels.     

High-Density Lipoprotein-Associated miR-223 Is Altered after Diet-Induced Weight Loss in Overweight and Obese Males

Background and Aims

microRNAs (miRNAs) are small, endogenous non-coding RNAs that regulate metabolic processes, including obesity. The levels of circulating miRNAs are affected by metabolic changes in obesity, as well as in diet-induced weight loss. Circulating miRNAs are transported by high-density lipoproteins (HDL) but the regulation of HDL-associated miRNAs after diet-induced weight loss has not been studied. We aim to determine if HDL-associated miR-16, miR-17, miR-126, miR-222 and miR-223 levels are altered by diet-induced weight loss in overweight and obese males.

Methods

HDL were isolated from 47 subjects following 12 weeks weight loss comparing a high protein diet (HP, 30% of energy) with a normal protein diet (NP, 20% of energy). HDL-associated miRNAs (miR-16, miR-17, miR-126, miR-222 and miR-223) at baseline and after 12 weeks of weight loss were quantified by TaqMan miRNA assays. HDL particle sizes were determined by non-denaturing polyacrylamide gradient gel electrophoresis. Serum concentrations of human HDL constituents were measured immunoturbidometrically or enzymatically.

Results

miR-16, miR-17, miR-126, miR-222 and miR-223 were present on HDL from overweight and obese subjects at baseline and after 12 weeks of the HP and NP weight loss diets. The HP diet induced a significant decrease in HDL-associated miR-223 levels (p = 0.015), which positively correlated with changes in body weight (r = 0.488, p = 0.032). Changes in miR-223 levels were not associated to changes in HDL composition or size.

Conclusion

HDL-associated miR-223 levels are significantly decreased after HP diet-induced weight loss in overweight and obese males. This is the first study reporting changes in HDL-associated miRNA levels with diet-induced weight loss.     

The Inhibition of the Highly Expressed Mir-221 and Mir-222 Impairs the Growth of Prostate Carcinoma Xenografts in Mice

Background

MiR-221 and miR-222 are two highly homologous microRNAs whose upregulation has been recently described in several types of human tumors, for some of which their oncogenic role was explained by the discovery of their target p27, a key cell cycle regulator. We previously showed this regulatory relationship in prostate carcinoma cell lines in vitro, underlying the role of miR-221/222 as inducers of proliferation and tumorigenicity.

Methodology/Principal Findings

Here we describe a number of in vivo approaches confirming our previous data. The ectopic overexpression of miR-221 is able, per se, to confer a high growth advantage to LNCaP-derived tumors in SCID mice. Consistently, the anti-miR-221/222 antagomir treatment of established subcutaneous tumors derived from the highly aggressive PC3 cell line, naturally expressing high levels of miR-221/222, reduces tumor growth by increasing intratumoral p27 amount; this effect is long lasting, as it is detectable as long as 25 days after the treatment. Furthermore, we provide evidence in favour of a clinical relevance of the role of miR-221/222 in prostate carcinoma, by showing their general upregulation in patient-derived primary cell lines, where we find a significant inverse correlation with p27 expression.

Conclusions/Significance

These findings suggest that modulating miR-221/222 levels may have a therapeutic potential in prostate carcinoma.     

miRNome traits analysis on endothelial lineage cells discloses biomarker potential circulating microRNAs which affect progenitor activities

Background

Endothelial progenitor cells (EPCs) play a fundamental role in not only blood vessel development but also post-natal vascular repair. Currently EPCs are defined as early and late EPCs based on their biological properties and their time of appearance during in vitro culture. Both EPC types assist angiogenesis and have been linked to ischemia-related disorders, including coronary artery disease (CAD).

Results

We found late EPCs are more mobile than early EPCs and matured endothelial cells (ECs). To pinpoint the mechanism, microRNA profiles of early EPCs late EPCs, and ECs were deciphered by small RNA sequencing. Obtained signatures made up of both novel and known microRNAs, in which anti-angiogenic microRNAs such as miR-221 and miR-222 are more abundant in matured ECs than in late EPCs. Overexpression of miR-221 and miR-222 resulted in the reduction of genes involved in hypoxia response, metabolism, TGF-beta signalling, and cell motion. Not only hamper late EPC activities in vitro, both microRNAs (especially miR-222) also hindered in vivo vasculogenesis in a zebrafish model. Reporter assays showed that miR-222, but not miR-221, targets the angiogenic factor ETS1. In contrast, PIK3R1 is the target of miR-221, but not miR-222 in late EPCs. Clinically, both miR-221-PIK3R1 and miR-222-ETS1 pairs are deregulated in late EPCs of CAD patients.

Conclusions

Our results illustrate EPCs and ECs exploit unique miRNA modalities to regulate angiogenic features, and explain why late EPC levels and activities are reduced in CAD patients. These data will further help to develop new plasma biomarkers and therapeutic approaches for ischemia-related diseases or tumor angiogenesis.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-802) contains supplementary material, which is available to authorized users.     

Circulating microRNA 132-3p and 324-3p Profiles in Patients after Acute Aneurysmal Subarachnoid Hemorrhage

Background

Aneurysmal subarachnoid hemorrhage (SAH) is a highly morbid and fatal condition with high rate of cognitive impairment and negative impact in quality of life among survivors. Delayed cerebral infarction (DCI) is one the major factors for these negative outcomes. In this study we compared the circulating microRNA profiles of SAH patients and healthy individuals, and the circulating microRNA profiles of SAH patients with and without DCI.

Methods

Peripheral blood samples on Day 7 after the onset of SAH were subjected to microarray analysis with Affymetrix miRNA 3.0 array and quantitative PCR analysis. SAH patients with (N = 20) and without DCI (N = 20) and Healthy controls (N = 20) were included for analyses.

Results

We demonstrated that 99 miRNAs were found to be dysregulated in the SAH patient group with DCI. 81 miRNAs were upregulated and 18 were downregulated. Findings from KEGG pathway analysis showed that miRNAs and target genes for axon guidance and TGF-beta signaling were involved, implying that the resulted differential miRNA expression pattern reflect the results of SAH instead of etiology of the disease. miR-132-3p and miR-324-3p showed distinctive upregulations in qPCR [miR-132: 9.5 fold (95%CI: 2.3 to 16.7) in DCI group and 3.4 fold (95%CI: 1.0 to 5.8) in Non-DCI group; miR-324: 4924 fold (95%CI: 2620 to 7228) in DCI group and 4545 fold (95%CI: 2408 to 6683) in non-DCI group]. However, there were no significant differences in fold changes between SAH patients with and without DCI [fold change ratios (mean+/-SD): 2.7+/-4.2 and 1.1+/-1.1 for miRNA-132 and miRNA-324].

Conclusion

Our study demonstrated that as compared to healthy control, miR-132 and miR-324 showed a upregulation in both SAH DCI and Non-DCI groups. However, the differences between the SAH DCI and non-DCI groups were not statistically significant.     

Cardiovascular and Cerebrovascular Disease Associated microRNAs Are Dysregulated in Placental Tissues Affected with Gestational Hypertension,Preeclampsia and Intrauterine Growth Restriction

Aims

To demonstrate that pregnancy-related complications are associated with alterations in cardiovascular and cerebrovascular microRNA expression. Gene expression of 32 microRNAs (miR-1-3p, miR-16-5p, miR-17-5p, miR-20a-5p, miR-20b-5p, miR-21-5p, miR-23a-3p, miR-24-3p, miR-26a-5p, miR-29a-3p, miR-33a-5p, miR-92a-3p, miR-100-5p, miR-103a-3p, miR-122-5p, miR-125b-5p, miR-126-3p, miR-130b-3p, miR-133a-3p, miR-143-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-181a-5p, miR-195-5p, miR-199a-5p, miR-208a-3p, miR-210-3p, miR-221-3p, miR-342-3p, miR-499a-5p, and miR-574-3p) was assessed in placental tissues, compared between groups (35 gestational hypertension, 80 preeclampsia, 35 intrauterine growth restriction and 20 normal pregnancies) and correlated with the severity of the disease with respect to clinical signs, delivery date, and Doppler ultrasound parameters. Initially, selection and validation of endogenous controls for microRNA expression studies in placental tissues affected by pregnancy-related complications have been carried out.

Results

The expression profile of microRNAs was different between pregnancy-related complications and controls. The up-regulation of miR-499a-5p was a common phenomenon shared between gestational hypertension, preeclampsia, and intrauterine growth restriction. Preeclamptic pregnancies delivering after 34 weeks of gestation and IUGR with abnormal values of flow rate in the umbilical artery demonstrated up-regulation of miR-1-3b. Preeclampsia and IUGR requiring termination of gestation before 34 weeks of gestation were associated with down-regulation of miR-26a-5p, miR-103a-3p and miR-145-5p. On the other hand, some of microRNAs (miR-16-5p, miR-100-5p, miR-122-5p, miR-125b-5p, miR-126-3p, miR-143-3p, miR-195-5p, miR-199a-5p, miR-221-3p, miR-342-3p, and miR-574-3p) were only down-regulated or showed a trend to down-regulation just in intrauterine growth restriction pregnancies requiring the delivery before 34 weeks of gestation.

Conclusion

Epigenetic changes induced by pregnancy-related complications in placental tissue may cause later onset of cardiovascular and cerebrovascular diseases in offspring.     

Circulating microRNAs and Outcome in Patients with Acute Heart Failure

Background

The biomarker value of circulating microRNAs (miRNAs) has been extensively addressed in patients with acute coronary syndrome. However, prognostic performances of miRNAs in patients with acute heart failure (AHF) has received less attention.

Methods

A test cohort of 294 patients with acute dyspnea (236 AHF and 58 non-AHF) and 44 patients with stable chronic heart failure (CHF), and an independent validation cohort of 711 AHF patients, were used. Admission levels of miR-1/-21/-23/-126/-423-5p were assessed in plasma samples.

Results

In the test cohort, admission levels of miR-1 were lower in AHF and stable CHF patients compared to non-AHF patients (p = 0.0016). Levels of miR-126 and miR-423-5p were lower in AHF and in non-AHF patients compared to stable CHF patients (both p<0.001). Interestingly, admission levels of miR-423-5p were lower in patients who were re-admitted to the hospital in the year following the index hospitalization compared to patients who were not (p = 0.0001). Adjusted odds ratio [95% confidence interval] for one-year readmission was 0.70 [0.53–0.93] for miR-423-5p (p = 0.01). In the validation cohort, admission levels of miR-423-5p predicted 1-year mortality with an adjusted odds ratio [95% confidence interval] of 0.54 [0.36–0.82], p = 0.004. Patients within the lowest quartile of miR-423-5p were at high risk of long-term mortality (p = 0.02).

Conclusions

In AHF patients, low circulating levels of miR-423-5p at presentation are associated with a poor long-term outcome. This study supports the value of miR-423-5p as a prognostic biomarker of AHF.     

MiRNA Analysis by Quantitative PCR in Preterm Human Breast Milk Reveals Daily Fluctuations of hsa-miR-16-5p

Background and Aims

Human breast milk is an extremely dynamic fluid containing many biologically-active components which change throughout the feeding period and throughout the day. We designed a miRNA assay on minimized amounts of raw milk obtained from mothers of preterm infants. We investigated changes in miRNA expression within month 2 of lactation and then over the course of 24 hours.

Materials and Methods

Analyses were performed on pooled breast milk, made by combining samples collected at different clock times from the same mother donor, along with time series collected over 24 hours from four unsynchronized mothers. Whole milk, lipids or skim milk fractions were processed and analyzed by qPCR. We measured hsa-miR-16-5p, hsa-miR-21-5p, hsa-miR-146-5p, and hsa-let-7a, d and g (all -5p). Stability of miRNA endogenous controls was evaluated using RefFinder, a web tool integrating geNorm, Normfinder, BestKeeper and the comparative ΔΔCt method.

Results

MiR-21 and miR-16 were stably expressed in whole milk collected within month 2 of lactation from four mothers. Analysis of lipids and skim milk revealed that miR-146b and let-7d were better references in both fractions. Time series (5H-23H) allowed the identification of a set of three endogenous reference genes (hsa-let-7d, hsa-let-7g and miR-146b) to normalize raw quantification cycle (Cq) data. We identified a daily oscillation of miR-16-5p.

Perspectives

Our assay allows exploring miRNA levels of breast milk from mother with preterm baby collected in time series over 48–72 hours.     

Micro-RNAs Let7e and 126 in Plasma as Markers of Metabolic Dysfunction in 10 to 12 Years Old Children

Background

Growing evidence shows that metabolic syndrome (MetS) is already starting in childhood however there is no consensus regarding how to diagnose this condition in pediatric population. Studies in adults show that altered levels of specific micro-RNAs are related with components of the MetS.

Objective

We determined the plasma levels of four MetS-associated micro-RNAs (miR-126, miR-132, mir-145 and Let-7e) in 10 to 12 years old children with or without MetS traits.

Design

Pediatric subjects were selected from a cohort of 3325 school-age children, and clustered by the absence (control, n = 30), or the presence of 1 (n = 50), 2 (n = 41) or 3 (n = 35) MetS traits according to Cook´s criteria. Micro-RNAs were isolated from plasma, and levels of miR-126, miR-132, miR-145 and Let-7e were determined by Taqman qPCR.

Results

Regression analysis of the different MetS traits regarding the different miRNAs analyzed showed that Let-7e presented a negative association with HDL-C levels, but a positive correlation with the number of MetS traits. Levels of miR-126 presented a positive correlation with waist circumference, waist to hip ratio, BMI, and plasma triglycerides and VLDL-C. Levels of miR-132 showed a positive correlation with waist to hip ratio. Plasma levels of Let-7e were increased (~3.4 fold) in subjects with 3 MetS traits, and showed significant AUC (0.681; 95%CI = [0.58, 0.78]; p < 0.001) in the ROC analysis which were improved when miR-126 was included in the analysis (AUC 0.729; p < 0.001). In silico analysis of the interaction of proteins derived from mRNAs targeted by Let7 and miR-126 showed an important effect of both Let-7e and miR-126 regulating the insulin signaling pathway.

Conclusions

These results suggest that changes in the plasma levels of Let-7e and miR-126 could represent early markers of metabolic dysfunction in children with MetS traits.     

MicroRNAs as Predictor Markers for Response to Interferon Treatment of Chronic Hepatitis C Genotype-4 in Egyptian Patients

Background

Hepatitis C virus genotype 4 (HCV-4) infection is common in the Middle East and Africa, with an extraordinarily high prevalence in Egypt. MicroRNAs (miRNAs) play an important role in various diseases, including HCV infection. The aim of the present study was to assess serum miR-122, miR-221 and miR-21 expression profiles in HCV-4 patients prior to treatment with HCV-4 combination therapy (pegylated alpha interferon and ribavirin) and to determine whether the miRNAs were associated with the drug response.

Methods

RNA was extracted from pretreatment serum samples, and miR-122, miR-221 and miR-21 levels were measured by quantitative PCR. The results were compared among patients with sustained virological responses (SVR) and non-responders (NR).

Results

The expression levels of miR-21 and miR-122 were significantly different between the SVR and NR groups. Receiver operator characteristic (ROC) analysis revealed that the sensitivity, specificity and positive predictive values of miR-21 were 82.2%, 77.3% and 88.1%, respectively, with a cut-off value of 1.7. The sensitivity, specificity and positive predictive values of miR-122 were 68.9%, 59.1% and 77.5%, respectively, with a cut-off value of 3.5.

Conclusion and Significance

miR-21 and miR-122 might be useful predictors for SVR in HCV-4 patients prior to the administration of combination therapy. A higher predictive response power was obtained for miR-21 than for miR-122. These results should reduce ineffective treatments.     

Carboplatin with Decitabine Therapy,in Recurrent Platinum Resistant Ovarian Cancer,Alters Circulating miRNAs Concentrations: A Pilot Study

Objective

Plasma miRNAs represent potential minimally invasive biomarkers to monitor and predict outcomes from chemotherapy. The primary goal of the current study—consisting of patients with recurrent, platinum-resistant ovarian cancer—was to identify the changes in circulating miRNA concentrations associated with decitabine followed by carboplatin chemotherapy treatment. A secondary goal was to associate clinical response with changes in circulating miRNA concentration.

Methods

We measured miRNA concentrations in plasma samples from 14 patients with platinum-resistant, recurrent ovarian cancer enrolled in a phase II clinical trial that were treated with a low dose of the hypomethylating agent (HMA) decitabine for 5 days followed by carboplatin on day 8. The primary endpoint was to determine chemotherapy-associated changes in plasma miRNA concentrations. The secondary endpoint was to correlate miRNA changes with clinical response as measured by progression free survival (PFS).

Results

Seventy-eight miRNA plasma concentrations were measured at baseline (before treatment) and at the end of the first cycle of treatment (day 29). Of these, 10 miRNAs (miR-193a-5p, miR-375, miR-339-3p, miR-340-5p, miR-532-3p, miR-133a-3p, miR-25-3p, miR-10a-5p, miR-616-5p, and miR-148b-5p) displayed fold changes in concentration ranging from -2.9 to 4 (p<0.05), in recurrent platinum resistant ovarian cancer patients, that were associated with response to decitabine followed by carboplatin chemotherapy. Furthermore, lower concentrations of miR-148b-5p after this chemotherapy regimen were associated (P<0.05) with the PFS.

Conclusions

This is the first report demonstrating altered circulating miRNA concentrations following a combination platinum plus HMA chemotherapy regiment. In addition, circulating miR-148b-5p concentrations were associated with PFS and may represent a novel biomarker of therapeutic response, with this chemotherapy regimen, in women with recurrent, drug-resistant ovarian cancer.     

MicroRNAs in Serum and Bile of Patients with Primary Sclerosing Cholangitis and/or Cholangiocarcinoma

Background and Aim

Patients with primary sclerosing cholangitis (PSC) are at high risk for the development of cholangiocarcinoma (CC). Analysis of micro ribonucleic acid (MiRNA) patterns is an evolving research field in biliary pathophysiology with potential value in diagnosis and therapy. Our aim was to evaluate miRNA patterns in serum and bile of patients with PSC and/or CC.

Methods

Serum and bile from consecutive patients with PSC (n = 40 (serum), n = 52 (bile)), CC (n = 31 (serum), n = 19 (bile)) and patients with CC complicating PSC (PSC/CC) (n = 12 (bile)) were analyzed in a cross-sectional study between 2009 and 2012. As additional control serum samples from healthy individuals were analyzed (n = 12). The miRNA levels in serum and bile were determined with global miRNA profiling and subsequent miRNA-specific polymerase chain reaction-mediated validation.

Results

Serum analysis revealed significant differences for miR-1281 (p = 0.001), miR-126 (p = 0.001), miR-26a (p = 0.001), miR-30b (p = 0.001) and miR-122 (p = 0.034) between patients with PSC and patients with CC. All validated miRNAs were significantly lower in healthy individuals. MiR-412 (p = 0.001), miR-640 (p = 0.001), miR-1537 (p = 0.003) and miR-3189 (p = 0.001) were significantly different between patients with PSC and PSC/CC in bile.

Conclusions

Patients with PSC and/or CC have distinct miRNA profiles in serum and bile. Furthermore, miRNA concentrations are different in bile of patients with CC on top of PSC indicating the potential diagnostic value of these miRNAs.     

MiRNA-615-5p Functions as a Tumor Suppressor in Pancreatic Ductal Adenocarcinoma by Targeting AKT2

Background

Aberrant microRNA (miRNA) expression is associated with tumor development. This study aimed to elucidate the role of miR-615-5p in the development of pancreatic ductal adenocarcinoma (PDAC).

Methods

Locked nucleic acid in situ hybridization (LNA-ISH) was performed to compare miR-615-5p expression in patients between PDAC and matched adjacent normal tissues. Effects of miR-615-5p overexpression on cell proliferation, apoptosis, colony formation, migration, and invasion were determined in the pancreatic cancer cell lines PANC-1 and MIA PaCa-2. Effects of miR-615-5p on AKT2 were examined by dual-luciferase reporter assay. Lentivirus expressing miR-615 was used to create stable overexpression cell lines, which were subsequently used in mouse xenograft and metastasis models to assess tumor growth, apoptosis and metastasis.

Results

miR-615-5p expression was significantly lower in PDAC than in adjacent normal tissues. Low levels of miR-615-5p were independently associated with poor prognosis (HR: 2.243, 95% CI: 1.190-4.227, P=0.013). AKT2 protein expression was inversely correlated with miR-615-5p expression (r=-0.3, P=0.003). miR-615-5p directly targeted the 3’-untranslated region of AKT2 mRNA and repressed its expression. miR-615-5p overexpression inhibited pancreatic cancer cell proliferation, migration, and invasion in vitro, and tumor growth and metastasis in vivo. Furthermore, miR-615-5p overexpression also induced pancreatic cancer cell apoptosis both in vitro and in vivo.

Conclusions

These results show that miR-615-5p inhibits pancreatic cancer cell proliferation, migration, and invasion by targeting AKT2. The data implicate miR-615-5p in the prognosis and treatment of PDAC.     

MicroRNA Signature Characterizes Primary Tumors That Metastasize in an Esophageal Adenocarcinoma Rat Model

Objective

To establish a miRNA signature for metastasis in an animal model of esophageal adenocarcinoma (EAC).

Background

The incidence of esophageal adenocarcinoma (EAC) has dramatically increased and esophageal cancer is now the sixth leading cause of cancer deaths worldwide. Mortality rates remain high among patients with advanced stage disease and esophagectomy is associated with high complication rates. Hence, early identification of potentially metastatic disease would better guide treatment strategies.

Methods

The modified Levrat’s surgery was performed to induce EAC in Sprague-Dawley rats. Primary EAC and distant metastatic sites were confirmed via histology and immunofluorescence. miRNA profiling was performed on primary tumors with or without metastasis. A unique subset of miRNAs expressed in primary tumors and metastases was identified with Ingenuity Pathway Analysis (IPA) along with upstream and downstream targets. miRNA-linked gene expression analysis was performed on a secondary cohort of metastasis positive (n=5) and metastasis negative (n=28) primary tumors.

Results

The epithelial origin of distant metastasis was established by IF using villin (VIL1) and mucin 5AC (MUC5AC) antibodies. miRNome analysis identified four down-regulated miRNAs in metastasis positive primary tumors compared to metastasis negative tumors: miR-92a-3p (p=0.0001), miR-141-3p (p=0.0022), miR-451-1a (p=0.0181) and miR133a-3p (p=0.0304). Six target genes identified in the top scoring networks by IPA were validated as significantly, differentially expressed in metastasis positive primary tumors: Ago2, Akt1, Kras, Bcl2L11, CDKN1B and Zeb2.

Conclusion

In vivo metastasis was confirmed in the modified Levrat’s model. Analysis of the primary tumor identified a distinctive miRNA signature for primary tumors that metastasized.     

Expression of adipose microRNAs is sensitive to dietary conjugated linoleic acid treatment in mice

Background

Investigation of microRNAs (miRNAs) in obesity, their genetic targets and influence by dietary modulators is of great interest because it may potentially identify novel pathways involved in this complex metabolic disorder and influence future therapeutic approaches. This study aimed to determine whether miRNAs expression may be influenced by conjugated linoleic acid (CLA), currently used to induce fat loss.

Methodology/Principal Findings

We determined retroperitoneal adipose tissue (rWAT) expression of five miRNAs related to adipocyte differentiation (miRNA-143) and lipid metabolism (miRNA-103 and -107) and altered in obesity (miRNA-221 and -222), using the TaqMan®MicroRNA Assay (Applied-Biosystems). In the first experiment, mice were fed with a standard fat diet and orally treated with sunflower oil (control group) and 3 or 10 mg CLA/day for 37 days. In the second experiment, mice were fed with a high fat diet for 65 days. For the first 30 days, mice received the same doses of CLA described above and, from that time onwards, animals received a double dose. Results showed that expression of selected miRNAs was modified in response to CLA treatment and metabolic status. Interestingly, a strong correlation was observed between miR-103 and -107 expression, as well as miR-221 and -222 in both experiments. Moreover, changes in miRNAs expression correlated with several adipocyte gene expressions: miR-103 and -107 correlated with genes involved in fatty acid metabolism whereas miR-221 and miR-222 correlated with the expression of adipocytokines. Regarding the minor changes observed in miR-143 expression, no differences in expression of adipogenic markers were observed.

Conclusions/Significance

Although elucidating the functional implications of miRNAs is beyond the scope of this study, these findings provide the first evidence that miRNAs expression may be influenced by dietary manipulation, reflecting or even contributing to the new metabolic state originated by CLA treatment.     

Identification of a Plasma Four-microRNA Panel as Potential Noninvasive Biomarker for Osteosarcoma

Background

Circulating microRNAs (miRNAs) are emerging as promising biomarkers for human cancer. Osteosarcoma is the most common human primary malignant bone tumor in children and young adults. The objective of this study was to investigate whether circulating miRNAs in plasma could be a useful biomarker for detecting osteosarcoma and monitoring tumor removal dynamics.

Methods

Plasma samples were obtained from 90 patients before surgery, 50 patients after one month of surgery, and 90 healthy individuals. The study was divided into three steps: First, initial screening of the profiles of circulating miRNAs in pooled plasma samples from healthy controls and pre-operative osteosarcoma patients using a TaqMan low density array (TLDA). Second, evaluation of miRNA concentration in individual plasma samples from 90 pre-operative osteosarcoma patients and 90 healthy controls by a quantitative real time PCR (qRT-PCR) assay. Third, evaluation of miRNA concentration in paired plasma samples from 50 pre- and post-operative osteosarcoma patients by qRT-PCR assay.

Results

Four plasma miRNAs including miR-195-5p, miR-199a-3p, miR-320a, and miR-374a-5p were significantly increased in the osteosarcoma patients. Receiver operating characteristics curve analysis of the combined populations demonstrated that the four-miRNA signature could discriminate cases from controls with an area under the curve of 0.9608 (95% CI 0.9307-0.9912). These 4 miRNAs were markedly decreased in the plasma after operation. In addition, circulating miR-195-5p and miR-199a-3p were correlated with metastasis status, while miR-199a-3p and miR-320a were correlated with histological subtype.

Conclusions

Our data suggest that altered levels of circulating miRNAs might have great potential to serve as novel, non-invasive biomarkers for osteosarcoma.