Differences In miRNA Profiles Research Articles

MicroRNAs are differentially expressed in equine plasma of horses with osteoarthritis and osteochondritis dissecans versus control horses.

Osteoarthritis (OA) is a leading cause of lameness in horses with no effective disease-modifying treatment and challenging early diagnosis. OA is considered a disease of the joint involving the articular cartilage, subchondral bone, synovial membrane, and ligaments. Osteochondritis dissecans (OCD) is a joint disease consisting of focal defects in the osteochondral unit which may progress to OA later in life. MicroRNAs (miRNAs) have been recognized as small non-coding RNAs that regulate a variety of biological processes and have been detected in biological fluids. MiRNAs are currently investigated for their utility as biomarkers and druggable targets for a variety of diseases. The current study hypothesizes that miRNA profiles can be used to actively monitor joint health and differences in miRNA profiles will be found in healthy vs diseased joints and that differences will be detectable in blood plasma of tested horses. Five horses with OA, OCD, and 4 controls (C) had blood plasma and synovial fluid collected. Total RNA, including miRNA was isolated before generating miRNA libraries from the plasma of the horses. Libraries were sequenced at the Schroeder Arthritis Institute (Toronto). Differential expression analysis was done using DESeq2 and validated using ddPCR. KEGG pathway analysis was done using mirPath v.3 (Diana Tools). 57 differentially expressed miRNAs were identified in OA vs C plasma, 45 differentially expressed miRNAs in OC vs C plasma, and 21 differentially expressed miRNAs in OA vs OCD plasma. Notably, miR-140-5p expression was observed to be elevated in OA synovial fluid suggesting that miR-140-5p may serve as a protective marker early on to attenuate OA progression. KEGG pathway analysis of differentially expressed plasma miRNAs showed relationships with glycan degradation, glycosaminoglycan degradation, and hippo signaling pathway. Interestingly, ddPCR was unable to validate the NGS data suggesting that isomiRs may play an integral role in miRNA expression when assessed using NGS technologies.

Characterization of miRNA profiling in konjac-derived exosome-like nanoparticles and elucidation of their multifaceted roles in human health.

Plant-derived exosome-like nanoparticles (ELNs) have demonstrated cross-kingdom capabilities in regulating intercellular communication, facilitating drug delivery, and providing therapeutic interventions in humans. However, the functional attributes of konjac-derived ELNs (K-ELNs) remain largely unexplored. This study investigates the isolation, characterization, and functional analysis of K-ELNs, along with the profiling and differential expression analysis of associated miRNAs in both K-ELNs and Konjac tissues. K-ELNs were successfully isolated and characterized from two konjac species using ultracentrifugation, followed by Transmission Electron Microscopy (TEM) and Nanoparticle Tracking Analysis (NTA). Small RNA sequencing identified a total of 3,259 miRNAs across all samples. Differential expression analysis revealed significant differences in miRNA profiles between K-ELNs and tissue samples. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis of target genes provided insights into their roles in modulating pathways associated with diseases such as cancer and neurodegenerative disorders. Additionally, six miRNAs were selected for validation of sequencing results via RT-qPCR. The 5'RLM-RACE method was employed to validate the cleavage sites between differentially expressed miRNAs (DEMs) and their predicted target genes, further substantiating the regulatory roles of miRNAs in konjac. The findings of this study enhance our understanding of the molecular mechanisms underlying the biological functions and applications of K-ELNs, laying the groundwork for future research into their potential therapeutic roles in human health.

Identification and detection of microRNA kidney disease biomarkers in liquid biopsies.

MicroRNAs (miRNAs) are emerging rapidly as a novel class of biomarkers of major organ disorders, including kidney diseases. However, current PCR-based detection methods are not amenable to development for high-throughput, cost-effective miRNA biomarker quantification. MiRNA biomarkers show significant promise for diagnosis and prognosis of kidney diseases, including diabetic kidney disease, acute kidney injury, IgA nephropathy and delayed graft function following kidney transplantation. A variety of novel methods to detect miRNAs in liquid biopsies including urine, plasma and serum are being developed. As miRNAs are functional transcripts that regulate the expression of many protein coding genes, differences in miRNA profiles in disease also offer clues to underlying disease mechanisms. Recent findings highlight the potential of miRNAs as biomarkers to detect and predict progression of kidney diseases. Developing in parallel, novel methods for miRNA detection will facilitate the integration of these biomarkers into rapid routine clinical testing and existing care pathways. Validated kidney disease biomarkers also hold promise to identify novel therapeutic tools and targets. http://links.lww.com/CONH/A43.

Abstract PR001: Assessing differences in miRNA profiles by race and ethnicity: Implications for creating an equitable ovarian cancer early detection test

Abstract Introduction: Assessing serum micro RNA (miRNA) profiles is an emerging technique for earlier detection of ovarian cancer. A panel of miRNAs for ovarian cancer prediction has been proposed, but it is unknown whether race and ethnicity may influence their expression. The goal of this study was to determine how race affects expression of miRNAs associated with ovarian cancer risk to ensure creation of an equitable test. Methods: Serum samples from 1586 women from the Mass General Brigham BioBank were analyzed for the presence of 179 different miRNAs. The Abcam Fireplex® assay was used to assess miRNA expression determined by flow cytometry, measured in mean fluorescence units (MFI) and log2 normalized prior to analysis. Demographic characteristics and medical histories were abstracted from linked electronic medical records. Patients with missing race/ethnicity were excluded. Differences in miRNA profiles by race/ethnicity (white, non-Hispanic vs non-white) were assessed using dimension reduction. The miRNA expression data was mapped to two-dimensions using constrained least-squares, then the reduced dimension data was used to train a simple neural network to predict race/ethnicity. In addition, pairwise t-test analyses were performed to analyze racial/ethnic differences among eight miRNAs previously reported to be informative for prediction of ovarian cancer. Results: The racial/ethnic composition of the study population was similar to the state population (76.9% white, 13.4% Hispanic, 5.2% black, 2.6% Asian, 1.9% Other). Non-white patients were on average younger (41.9 years ± 13.2 vs 51.3 years ± 15.1, p<0.01) and had fewer comorbid conditions compared to white patients (3.5 comorbidities ± 2.7 vs 4.6 comorbidities ± 2.8, p<0.01). The dimension reduction and classification analysis showed a significant effect of race on miRNA profiles, with miRNAs able to predict race at an AUC of 0.71 (95% CI 0.68-0.74) after 10-fold cross validation. The AUC remained consistent when stratified for age, menopausal status, and comorbidities. Among eight miRNAs highly predictive of ovarian cancer, seven significantly varied by race (hsa-mir-150-5p, hsa-mir-200c-3p, hsa-mir-23b-3p, has-mir-29a-3p, hsa-mir-320c, hsa-mir-320d, and hsa-mir-32-5p, p<0.01). Hsa-mir-200c-3p was the most significantly different by race (7.19 mean log2 MFI among non-white vs 6.94 mean log2 MFI among white patients, p<0.01). Upon analyzing each racial subtype and variation in hsa-mir-200c-3p, black and Hispanic patients had relatively similar mean values which were significantly different from values observed among white patients. Conclusions: miRNA expression is significantly influenced by race and ethnicity, with differences remaining largely consistent even after controlling for confounders. Understanding baseline differences in biomarker test characteristics prior to clinical implementation of novel diagnostic tools is essential to ensuring instruments perform comparably across diverse populations. Citation Format: Stephanie Alimena, James Webber, Laura Wollborn, Marta Williams, Chad B. Sussman, Joyce Y. Wang, Julia Spiegel, Kevin M. Elias. Assessing differences in miRNA profiles by race and ethnicity: Implications for creating an equitable ovarian cancer early detection test [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PR001.

The potential of three whole blood microRNAs to predict outcome and monitor treatment response in sarcoid-bearing equids

MicroRNAs (miRNAs) have been proposed as biomarkers for equine sarcoid (ES) disease. In this study, the suitability of three whole blood miRNAs to diagnose ES and to predict and monitor the outcome of therapy was explored. Using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), expression levels of eca-miR-127, eca-miR-379, and eca-miR-432 in whole blood of ES-affected equids before and at least one year after therapy were compared to those of unaffected control equids. Associations of age, sex, species, diagnosis, and therapy outcome with miRNA expression levels were examined using general linear models. In total, 48 ES-affected equids and 47 control equids were recruited. From the affected animals, 31 responded favorably to treatment, and 17 demonstrated a failure of therapy. None of the tested miRNAs were influenced by age. Male equids showed increased expression of eca-miR-127 compared to females and horses showed higher expression levels of eca-miR-379 and eca-miR-432 than donkeys. Eca-miR-127 was confirmed as a diagnostic discriminator between ES-affected and control equids. No difference in miRNA profiles before therapy was found when comparing ES-affected equids with success vs. failure of therapy. Eca-miR-379 and eca-miR-432 decreased over time in horses where therapy was successful, but not in those cases where it failed. Biological variables influence equine whole blood miRNA expression, which may complicate biomarker validation. While none of the tested miRNAs could predict the response to therapy in ES-affected equids and eca-miR-127 showed poor diagnostic accuracy for ES, eca-miR-379 and eca-miR-432 miRNAs might allow refinement of monitoring of success of ES therapy.

Investigating differential miRNA expression profiling using serum and urine specimens for detecting potential biomarkers for early prostate cancer diagnosis

Background/aimMicroRNAs (miRNAs) are known up-to-date candidate biomarkers for several diseases. In addition, obtaining miRNA from different body fluids such as serum, plasma, saliva, and urine is relatively easy to handle. Herein we aimed to detect miRNAs as biomarkers for early stage prostate cancer (PC). For this purpose, we used urine and serum samples to detect any significant differences in miRNA profiles between patients and healthy controls.Materials and methodsTotal ribonucleic acid (RNA) in urine and serum samples were isolated from eight untreated PC patients, thirty healthy individuals were screened for miRNA profile, and candidate miRNAs were validated. Whole urinary and serum miRNA profile was analyzed using Affymetrix GeneChip miRNA 4.0 Arrays. Candidate miRNAs were investigated by stem-loop reverse transcription-polymerase chain reaction.ResultsWhen we analyzed the urinary samples of PC patients, 49 miRNAs were detected to be upregulated and 14 miRNAs were found to be downregulated when compared with healthy controls. According to the serum samples, 19 miRNAs were found to be upregulated, and 21 miRNAs were found to be downregulated when compared with healthy individuals as well. Interestingly, we detected only four overlapping miRNAs (MIR320A, MIR4535, MIR4706, MIR6750) that commonly increase or decrease in both serum and urine samples. Among them, MIR320A was found to be downregulated, and MIR4535, MIR4706, and MIR6750 were found to be upregulated for urine samples. However, only MIR6750 was upregulated and the other three miRNAs were downregulated for serum samples.ConclusionNotably, the expression profile of MIR320A was significantly altered in urine specimens of prostate cancer patients. We considered that MIR320A has been evaluated as a valuable biomarker that can be used in the early diagnosis of PC.

MiRNA expression of hepatocytes derived from induced pluripotent stem cells of coronary artery disease patients

Background and Aims: Identifying the coronary artery disease (CAD) patients with an increased risk for acute infarction is an ongoing challenge. CAD is often accompanied by abnormal serum composition of molecular lipids, however, the mechanisms behind this change are unknown. Liver contributes largely to serum lipids and miRNAs are known to regulate key pathways of lipid metabolism. In this work we investigated differences in miRNA profiles of iPSC-derived hepatocytes from acute and stable CAD patients and healthy individuals to shed more light on atherogenic mechanisms and discover new biomarkers.

Extracellular Vesicles in Synovial Fluid from Rheumatoid Arthritis Patients Contain miRNAs with Capacity to Modulate Inflammation

In rheumatoid arthritis (RA), extracellular vesicles (EVs) are associated with both the propagation and attenuation of joint inflammation and destruction. However, the specific EV content responsible for these processes is largely unknown. Investigations into identifying EV content are confounded by the challenges in obtaining high-quality EV preparations from synovial fluid. Implementing a size exclusion chromatography-based method of EV isolation, coupled with small RNA sequencing, we accurately characterised EV miRNAs in synovial fluid obtained from RA patients and investigated the differences between joints with high- and low-grade inflammation. Synovial fluid was obtained from the joints of 12 RA patients and, based on leukocyte counts, classified as either high (n = 7)- or low (n = 5)-grade inflammation. Using size exclusion chromatography, EVs were purified and small RNA was extracted and sequenced on a NextSeq 500. Sequencing reads were aligned to miRBase v21, and differences in miRNA profiles between RA patients with high- and low-grade joint inflammation were analysed. In total, 1972 distinct miRNAs were identified from RA synovial fluid EVs. miRNAs with less than five reads in fewer than five patients were filtered out, leaving 318 miRNAs for analysis. Analysis of the most abundant miRNAs suggested that they negatively regulate multiple genes relevant to inflammation, including signal transducer and activator of transcription 3 (STAT3), which lies downstream of IL-6 and has a pro-inflammatory role in RA. Synovial fluid from joints with high-grade inflammation contained 3.5-fold more EV miRNA per mL of synovial fluid (p = 0.0017). Seventy-eight EV miRNAs were differentially expressed between RA joints with high- and low-grade inflammation, and pathway analysis revealed that their target genes were commonly involved a variety of processes, including cellular apoptosis, proliferation and migration. Of the 49 miRNAs that were elevated in joints with high-grade inflammation, pathway analysis revealed that genes involved in cytokine-mediated signalling pathways were significantly enriched targets. In contrast, genes associated with reactive oxygen species signalling were significantly enriched as targets of the 29 miRNAs elevated in joints with low-grade inflammation. Our study identified an abundance of EV miRNAs from the synovial fluid of RA patients with the potential to modulate inflammation. In doing so, we defined potential mechanisms by which synovial fluid EVs may contribute to RA pathophysiology.

Secondary mitral regurgitation-Insights from microRNA assessment.

BackgroundWhile secondary mitral regurgitation (sMR) is associated with adverse outcome in heart failure with reduced ejection fraction (HFrEF), key pathophysiologic mechanisms remain poorly understood and might be elucidated by microRNAs (miRNA/miR), that were recently related to cardiac remodelling. This study sought to assess (i) the differences of miRNA profiles in patients with severe sMR compared to matched disease controls, (ii) the correlation between circulating miRNAs and surrogates of sMR severity as well as (iii) the prognostic implications of miRNA levels in severe sMR.Materials and methodsSixty‐six HFrEF patients were included, of these 44 patients with severe sMR 2:1 matched to HFrEF controls with no/mild sMR. A comprehensive set of miRNAs (miR‐21, miR‐29a, miR‐122, miR‐132, miR‐133a, miR‐let7i) were measured and correlated to echocardiographic sMR severity.ResultsmiRNA patterns differed distinctly between patients with severe sMR and HFrEF controls (P < .05). Among the panel of assessed miRNAs, miR‐133a correlated most strongly with surrogates of sMR severity (r = −0.41, P = .001 with sMR vena contracta width). Interestingly, elevated levels of miR‐133 were associated with an increased risk for cardiovascular death and/or HF hospitalizations with and adjusted HR of 1.85 (95% CI 1.24‐2.76, P = .003).ConclusionsThis study unveils distinct pathophysiologic maladaptions at a cellular level in patients with severe sMR compared to no/mild sMR by showing significant differences in miRNA profiles and correlations with sMR severity, supporting the concept that sMR drives cardiac remodelling in heart failure. Moreover, the increased risk for adverse outcome in HFrEF patients with severe sMR conveyed by miR‐133a might indicate irreversible myocardial damage.

Genome-wide miRNA profiling in plasma of pregnant women with down syndrome fetuses

Down syndrome (DS) is one of the most common causes of intellectual disability and new approaches allowing its rapid and effective prenatal detection are being explored. In this study, we investigated the diagnostic potential of plasma microRNAs (miRNAs). This study builds upon our previous study in DS placentas, where seven miRNAs were found to be significantly up-regulated. A total of 70 first-trimester plasma samples from pregnant women were included in the present study (35 samples with DS fetuses; 35 with euploid fetuses). Genome-wide miRNA profiling was performed in the pilot study using Affymetrix GeneChip™ miRNA 4.1 Array Strips (18 samples). Selected miRNAs were then analysed in the validation study using quantitative reverse transcription PCR (RT-qPCR; 52 samples). Based on the current pilot study results (12 miRNAs), our previous research on chorionic villi samples (7 miRNAs) and the literature (4 miRNAs), a group of 23 miRNAs was selected for the validation study. Although the results of the pilot study were promising, the validation study using the more sensitive RT-qPCR technique and a larger group of samples revealed no significant differences in miRNA profiles between the compared groups. Our results suggest that testing of the first-trimester plasma miRNAs is probably not suitable for non-invasive prenatal testing (NIPT). Different results could be theoretically achieved at later gestational ages; however, such a result probably would have limited use in clinical practice.

Customized hepatocellular carcinoma prediction panel

Abstract Background West Africa is a hotbed of hepatocellular carcinoma (HCC) partly due to aflatoxin B (AFB) contamination. In Russia, there is now a pool of patients who have liver cirrhosis due to hepatitis C virus (HCV), who were treated with direct antiviral agents and HCV negative, but due to cirrhosis are in the risk group for HCC development. MiRNAs are candidate molecules for HCC prediction panel. The question is if it is possible to use the same miRNAs for HCC development risk despite background or it is reasonable to have a special miRNA set according to background (for example, HCC, HBV, continuous AFB consumption etc.). Methods Samples from Somalia: 40 plasmas of HCV negative patients with HCC, 8 plasmas of HCV positive patients with HCC, 22 plasmas of HCV-negative patients with liver cirrhosis, 8 plasmas of HCV-positive patients with liver cirrhosis, 11 plasmas from healthy students living outside West Africa last 9-12 months as control group. Samples from Russia: 12 plasmas of patients with HCC (HCV+ and HCV-) and 30 plasmas of patients with liver cirrhosis, 11 plasmas from healthy donors as control group. Exosomes were isolated from plasma by differential ultracentrifugation following free-flow electrophoresis. MiRNA let-7a-5p, -224-5p, -106b-3p, -126-5p, -122-5p, -16-5p and -34a-5p were determined in exosomes by qPCR-RT. Same free miRNA from plasma were determined. Plasma samples were examined for AFB1. Results There is an interesting tendency for miRNA-21 and mi-RNA-122: on the stage of cirrhosis in Somalian samples there is a significant difference in expression levels that disappears on the HCC stage. Profiles of free miRNAs circulating in plasma were not significantly different between the groups. There was a difference in exosomal miRNA profile of plasma from patients with HCC and cirrhosis for both (Russia and Somalia) group of samples. Conclusions The difference in miRNA profiles of HCC patients on the background of HCV or aflatoxins consumption may allow supposing different epigenetics dysregulation happening in HCC depending on the trigger factor. According to our results, exosomal miRNA identification in HCC patients seem to be more accurate than plasma free miRNAs and it seems reasonable to modify biomarker panel for HCC risk according to the case background it is intended to work for. Legal entity responsible for the study The authors. Funding Ministry of Science and Higher Education of the Russian Federation Project 5-100. Disclosure All authors have declared no conflicts of interest.

Endometrial Liquid Biopsy Provides a miRNA Roadmap of the Secretory Phase of the Human Endometrium.

Endometrial liquid biopsy (ELB) is a minimally invasive alternative for research and diagnosis in endometrial biology. We sought to establish an endometrial micro ribonucleic acid (miRNA) roadmap based on ELB during the secretory phase of the menstrual cycle in both natural and hormonal replacement therapy (HRT) cycles. Human ELB samples (n = 58) were obtained from healthy ovum donors undergoing a natural and an HRT cycle consecutively. miRNA profiles were identified using next-generation sequencing (NGS). For functional analysis, messenger ribonucleic acid targets were chosen among those reported in the endometrial receptivity analysis. The human endometrial secretory phase is characterized by a dynamic miRNA secretion pattern that varies from the prereceptive to the receptive stages. No differences in miRNA profiles were found among natural versus HRT cycles in the same women, reinforcing the similarities in functional and clinical outcomes in natural versus medicated cycles. Bioinformatic analysis revealed 62 validated interactions and 81 predicted interactions of miRNAs differentially expressed in the HRT cycle. Annotation of these genes linked them to 51 different pathways involved in endometrial receptivity. This NGS-based study describes the miRNA signature in human ELB during the secretory phase of natural and HRT cycles. A consistent endometrial miRNA signature was observed in the acquisition of endometrial receptivity. Interestingly, no significant differences in miRNA expression were found in natural versus HRT cycles reinforcing the functional clinical similarities between both approaches.

Identification of microRNA signatures in umbilical cord blood associated with maternal characteristics.

BackgroundUmbilical cord blood could serve as useful source of blood markers enabling more efficient and reliable prenatal and neonatal diagnostics. MicroRNAs (miRNAs) are ubiquitous in body fluids where they were used for detecting and monitoring various physiological and pathological conditions. In this descriptive study, we aimed to identify changes in miRNA expression profiles associated with basic maternal somatic and epidemiological characteristics.MethodsStudy is based on 24 mothers from the Pilot phase of CELSPAC: TNG (Central European Longitudinal Studies of Parents and Children: The Next Generation) study. Cord blood was collected at time of delivery and global miRNA profiling was performed using microRNA Ready-to-use PCR Human Panel I+II TaqMan microarrays. Expression profiles were statistically evaluated in relation to maternal age, BMI, pregnancy weight gain, blood type, Rh factor status, allergies during pregnancy, addictive substance abuse and smoking status.ResultsWe analyzed expression of 752 human mature miRNAs in 24 samples of umbilical cord blood. For all maternal characteristics tested we described a specific signature of significantly deregulated miRNAs (P < 0.05). Analysis revealed seven miRNA associated with maternal age (three increased and four decreased in women younger than 35 years), 14 miRNAs associated with BMI status (five miRNAs increased and nine miRNAs decreased in women with BMI > 25) and nine miRNAs associated with maternal weight gain during pregnancy (eight miRNAs increased, and one miRNA decreased in women with weight gain < 12 kg). Additionally, 17 miRNAs correlated to blood type (two miRNAs decreased in blood type A, 11 increased in blood type B, two miRNAs increased in blood type AB and two miRNAs increased in blood type 0) and 17 miRNAs to Rh status of mother. We also detected seven miRNAs deregulated in umbilical cord blood of women with allergy (four increased and three decreased in women with allergy), four miRNAs associated to addictive substance abuse status (two up- and two downregulated in women with addictive substance abuse) and eight miRNAs associated with maternal cigarette smoking during pregnancy.ConclusionsWe successfully described differences in miRNA profiles in umbilical cord blood associated with basic characteristics connected with mother. Our data suggest that miRNAs in umbilical cord blood are detectable and associated with a wide range of maternal characteristics. These results indicate that miRNAs could potentially serve, and should be studied, as biomarkers for screening and diagnosis of pregnancy-associated complications and pathologies.

Downregulation of miR-218-5p promotes invasion of oral squamous cell carcinoma cells via activation of CD44-ROCK signaling

The invasion front of oral squamous cell carcinoma (OSCC) harbors the most aggressive cells of the tumor and is critical for cancer invasion and metastasis. MicroRNAs (miRNAs) play important roles in OSCC progression. In this study, we modelled the OSCC invasion front on a microfluidic chip, and investigated differences in miRNA profiles between cells in the invasion front and those in the tumor mass by small RNA sequencing. We found that miR-218-5p was downregulated in invasion front cells and negatively regulates OSCC invasiveness by targeting the CD44–ROCK pathway. Thus, miR-218-5p may serve as a useful therapeutic target for OSCC. Moreover, invasion front cell isolation based-on microfluidic technology provided a useful strategy for cancer invasion study.

MicroRNA Profiling Reveals Distinct Profiles for Tissue-Derived and Cultured Endothelial Cells

Endothelial plasticity enables the cells to switch their phenotype according to the surrounding vascular microenvironment. MicroRNAs (miRNAs) are small noncoding RNAs that control endothelial plasticity. The objective of this study was to investigate the differences in miRNA profiles of tissue-derived cells and cultured endothelial cells. To this end, miRNA expression was profiled from freshly isolated tissue-derived human vascular endothelial cells and endothelial cells cultured until cellular senescence using miRNA sequencing. In addition, the data was searched for putative novel endothelial miRNAs and miRNA isoforms. The data analysis revealed a striking change in endothelial miRNA profile as the cells adapted from tissue to cell culture environment and the overall miRNA expression decreased significantly in cultured compared to tissue-derived endothelial cells. In addition to changes in mechanosensitive miRNA expression, alterations in senescence-associated and endothelial-to-mesenchymal-transition-associated miRNAs were observed in aging cells. Collectively, the data illustrates the adaptability of endothelial cell miRNA expression that mirrors prevailing cellular environment.

Using genomics to predict antidepressant response in suicidal depressed children

BackgroundDepression and anxiety disorders are among the most common childhood psychiatric disorders. Selective serotonin reuptake inhibitors (SSRIs) are generally considered first-line treatment for both depression and anxiety in this age group. However, it has been reported that 30%–40% of all patients who receive a sufficient dose and duration of treatment fail to respond. Moreover, SSRI use is frequently associated with serious adverse events (SAE), including activation symptoms, manic switch and increased suicidal behavior. These are particularly relevant in pediatric populations because of concerns about the suicide threat of SSRIs, resulting in a black-box warning. Currently there is no way of knowing in advance who of the patients will respond. Identification of biomarkers that would be early predictors of response and of the occurrence of SAE could help to maximize the benefit–risk ratio for the use of SSRIs, and speed up the matching of treatment to patient. The main objective of this project is therefore to identify and validate biomarkers predicting response and SAE in depressed children and adolescents, thus improving treatment, enabling the development of novel diagnostic tests and suggest novel therapeutic targets for future related drug development.MethodsAs a preliminary pilot, we already obtained blood samples from 80 depressed and anxious children and adolescents over the last year before, during and after eight weeks of fluoxetine (FLU) therapy. Genetic and epigenetic samples were collected from all participants. The patients were treated with FLU 20–40 mg/day for 8 weeks. Clinical response was measured with several scales including the Children's Depression Rating Scale–Revised (CDRS-R), the Beck Depression Inventory (BDI) and the Screen for Child Anxiety Related Emotional Disorders (SCARED).ResultsThe participant's age ranged from 6 to 18 (14.12 ± 2.30) years. The overall response rate was 56%. Ten percent responded with SAE. Regarding Pharmacogenetics, The 5-HTTLPR ss genotype was associated with a poorer clinical response with regard to depressive symptoms as well with fewer reports of agitation compared to the ll genotype. Regarding immune measures, we analyzed cytokine levels from 41 children. Plasma concentrations of TNF-α, IL-6 and IL-1β were measured by enzyme linked immunosorbent assays (ELISA) before and after FLU treatment. Antidepressant treatment significantly reduced TNF-α levels (P = 0.037), with no significant changes in the levels of IL-6 and IL-1β. All three pro-inflammatory cytokines were significantly (P &lt; 0.05) higher in SSRI-refractory than SSRI-responsive patients, i.e.: higher levels of TNF-α, IL-6 and IL-1β might predict non-response to fluoxetine treatment in children.Future plansOut of the study sample we selected 13 remitters and 13 non-responders and 10 children with SAE (activation symptoms, manic/hypomanic switch, increased suicidality), and analyzed expression profiles in peripheral blood at admission and after 8 weeks of treatment using illumine Truseq technique. Hopefully, we shall find significant differences in miRNA profiles between the different groups which may serve as biomarkers indicating AD treatment response and SAE. The differentially regulated miRNA's can be studied in depth in the future in animal models in order to support the hypothesis that they may be involved in the AD mechanism.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Urinary microRNAs as potential biomarkers of pesticide exposure

MicroRNAs (miRNAs) are post-transcriptional regulators that silence messenger RNAs. Because miRNAs are stable at room temperature and long-lived, they have been proposed as molecular biomarkers to monitor disease and exposure status. While urinary miRNAs have been used clinically as potential diagnostic markers for kidney and bladder cancers and other diseases, their utility in non-clinical settings has yet to be fully developed. Our goal was to investigate the potential for urinary miRNAs to act as biomarkers of pesticide exposure and early biological response by identifying the miRNAs present in urine from 27 parent/child, farmworker/non-farmworker pairs (16FW/11NFW) collected during two agricultural seasons (thinning and post-harvest) and characterizing the between- and within-individual variability of these miRNA epigenetic regulators. MiRNAs were isolated from archived urine samples and identified using PCR arrays. Comparisons were made between age, households, season, and occupation. Of 384 miRNAs investigated, 297 (77%) were detectable in at least one sample. Seven miRNAs were detected in at least 50% of the samples, and one miRNA was present in 96% of the samples. Principal components and hierarchical clustering analyses indicate significant differences in miRNA profiles between farmworker and non-farmworker adults as well as between seasons. Six miRNAs were observed to be positively associated with farmworkers status during the post-harvest season. Expression of five of these miRNA trended towards a positive dose response relationship with organophosphate pesticide metabolites in farmworkers. These results suggest that miRNAs may be novel biomarkers of pesticide exposure and early biological response.

Uterine leiomyosarcoma and endometrial stromal sarcoma have unique miRNA signatures

ObjectiveTo compare the microRNA (miRNA) profiles of uterine endometrial stromal sarcoma (ESS) and leiomyosarcoma (LMS), and to compare the miRNA signatures of primary and metastatic uterine LMS. MethodsEight primary LMS, 9 primary ESS and 8 metastatic LMS were analyzed for miRNA profiles using TaqMan Human miRNA Array Cards. Findings for 20 differentially expressed miRNAs were validated in a series of 44 uterine sarcomas (9 primary uterine ESS, 17 primary uterine LMS, 18 metastatic LMS) using qPCR. Frizzled-6 protein expression was analyzed in 30 LMS (15 primary, 15 metastases). Frizzled-6 was silenced in SK-LMS-1 uterine LMS cells using siRNA and the effect on invasion, wound healing and matrix metalloproteinase-2 (MMP2) activity was assessed. ResultsNinety-four miRNAs were significantly differentially expressed in ESS and LMS, of which 76 were overexpressed in ESS and 18 overexpressed in LMS. Forty-nine miRNAs were differentially expressed in primary and metastatic LMS, of which 45 were overexpressed in primary LMS and 4 in metastases. Differential expression was confirmed for 10/20 miRNA analyzed using qPCR. Frizzled-6 silencing in SK-LMS-1 cells significantly inhibited cellular invasion, wound healing and MMP-2 activity. ConclusionsDifferential miRNA signatures of ESS and LMS provide novel data regarding transcriptional regulation in these cancers, based on which new potential diagnostic markers, prognostic biomarkers and therapeutic targets may be explored. Differences in miRNA profiles of primary and metastatic LMS may improve our understanding of disease progression in this aggressive malignancy.

Bone Metastasis-Related MicroRNAs: New Targets for Treatment?

MicroRNAs (miRNAs) are a new class of small noncoding RNAs of 19-25 nucleotides that function as negative posttranscriptional gene regulators. MiRNAs hybridize to the 3' untranslated region (UTR) of target mRNAs and repress translation or mediate mRNA cleavage. MiRNAs critically regulate tumorigenesis and progression by targeting oncogenes, tumor suppressor genes, or genes related to proliferation, angiogenesis, and apoptosis. Different tumor types and tumors at different stages exhibit unique miRNA profiles. MiRNAs show promise as potential biomarkers for cancer diagnostics, progression, and response to treatment. The role of miRNAs in promoting bone metastases is under investigated. We summarize recent findings on the mechanisms by which miRNAs may regulate bone metastatic spread of breast cancer, prostate cancer, lung cancer and multiple myeloma. We review similarities and differences in miRNA profiles that may explain the variety of molecular pathways underling metastatic spread to the skeleton in different cancers. Finally, we discuss the exciting potential of using miRNAs as diagnostics and therapeutic targets to reduce the risk of bone metastases in cancer, from the perspective of data provided by recent pre-clinical and clinical studies.

Exogenous oxytocin modulates human myometrial microRNAs

MicroRNAs (miRNAs) play a modulatory role in pathways that lead to labor onset, although oxytocin is known to modulate gene expression within the myometrium. We aimed to identify miRNAs whose expression is regulated by oxytocin in pregnant human myometrium. Myometrial miRNA expression profiles were compared between samples collected from women at term before the onset of labor (no labor; n = 8) and after labor onset after early exogenous oxytocin treatment (n = 8). Multivariate modelling was used to assess differences in miRNA profiles. Biologic validation was undertaken on 3 independent patient cohorts (no labor, n = 10; labor induced with oxytocin, n = 8; and spontaneous labor with no oxytocin treatment, n = 10). In vitro studies that used primary myocytes were undertaken to assess target miRNA expression after oxytocin treatment. Target genes of candidate miRNAs were identified in silico and cross-referenced with genes that are known to be associated with labor or expressed in myometrium. In total, 1309 miRNAs were analyzed by microarray, of which 494 were detected in human myometrium. Multivariate modeling identified 12 target miRNAs the differential expression of which was most responsible for the observed separation of the 2 patient populations in the primary discovery cohorts. Biologic validation in the independent secondary sample cohorts showed that oxytocin independently regulated 5 miRNAs (hsa-miR-146b-3p, hsa-miR-196b-3p, hsa-miR-223-3p, hsa-miR-873-5p, and hsa-miR-876-5p). Additionally, hsa-miR-146b-3p was increased both in labor that was induced with oxytocin and in myometrium from spontaneous labor with no oxytocin treatment compared with no labor samples. Four of the validated miRNAs (hsa-miR-146a-5p, hsa-miR-146b-3p, hsa-miR-196b-3p, and hsa-miR-876-5p) were expressed in primary human myocytes; oxytocin treatment of these cells replicated the directional changes that were observed in vivo. Oxytocin alters the expression of a unique set of myometrial miRNAs. These results suggest a further role for oxytocin as a signaling molecule that is involved in the regulation of gene expression during parturition.