Expression Of Small Non-coding RNAs Research Articles

Characterization of small RNAs in the spleen of MASH in a non-human primate model

Metabolic dysfunction-associated steatotic liver disease (MASLD) and its advanced stage, metabolic dysfunction-associated steatohepatitis (MASH), are increasingly recognized as a global health issue. This study examines the role of small RNAs in the spleen of MASH using a non-human primate model. We performed high-throughput small RNA sequencing on spleen tissues from MASH-primates, revealing significant alterations in the expression of small non-coding RNAs, especially miRNAs. Notably, miR-96, miR-182, miR-183, and miR-122 showed differential expression in MASH spleens. Predictive and validation studies have identified potential target genes, such as PTX3 and NFIX, that were significantly dysregulated in spleens of MASH. These findings characterized small RNAs in spleen of MASH and offer a novel insight for further research for MASH.

P-414 Evaluation of small non-coding RNAs in uterine fluid in the diagnosis of endometrial receptivity in assisted reproductive technology programs

Abstract Study question To analyze endometrial receptivity in patients undergoing frozen-thawed embryo transfer (FET) based on the expression of small non-coding RNAs (sncRNAs): microRNAs and piwiRNAs. Summary answer According to our studies, the expression of sncRNAs in uterine aspirate may become an additional non-invasive and effective way to determine endometrial receptivity. What is known already Today, infertility remains an important medical and social problem. According to statistics, the effectiveness of ART programs remains at the level of 30-40%. Violation of the implantation mechanism is associated with a shift in the “implantation window” period and endometrial receptivity. Therefore, the search for an ideal marker of endometrial receptivity is a priority. Studying the expression of sncRNAs in endometrial secretions or uterine aspirate may become a potential marker of endometrial receptivity. Study design, size, duration The study included 102 infertile couples with women aged from 23 to 40 years. The patients were divided into two groups depending on the preparation of the endometrium for the FET: group 1 - 42 patients with natural cycle (NC); group 2 - 60 patients with hormone replacement therapy (HRT). SncRNAs were assessed in uterine aspiration on the day of FET. Participants/materials, setting, methods Uterine fluid was carried out in a volume of 5 to 50 μl with noninvasive technique. Next, the material was sent to the laboratory of applied transcriptomics for identification of sncRNAs. Quantitative assessment of sncRNAs in the endometrial secretion on the day of FET was carried out by deep sequencing on the NextSeq 500/550 platform (Illumina). Main results and the role of chance Logistic regression models were constructed for predicting pregnancy and endometrial receptivity based on the expression profiles of microRNAs and piwiRNAs in uterine aspirate, which are with 95% sensitivity and 74% specificity in the case of a combination of miR-34c-5p, miR-363–3p, miR-1180–3p, miR-361–3p, miR-183–5p (AUC = 0.91, p < 0.001) or with 74% sensitivity and 87% specificity in the case of a combination of molecules piR_004152, piR_020541, piR_001318, piR_014923, piR_017716 (AUC = 0.81, p < 0.001) determine the readiness of the endometrium for embryo implantation in the FET. In the NC and HRT groups, statistically significant differences were established between patients who became pregnant and patients with a negative result of the ART program in terms of baseline progesterone levels (p < 0.001). In the HRT group, positive correlations were revealed between endometrial thickness on the day of embryo transfer and the baseline level of progesterone (p = 0.04, r = 0.28). Limitations, reasons for caution The study was limited in sample size of patients and requires further randomized studies. Wider implications of the findings For the first time, a test system has been developed for assessing endometrial receptivity based on the expression of sncRNAs in patients both in the NC and in the HRT during the FET. It was found that increased initial progesterone levels correlate with positive outcomes of ART programs. Trial registration number not applicable

MiRNA-targeting oligonucleotide constructs with various mechanisms of action as effective inhibitors of carcinogenesis

INTRODUCTION. The development of malignant neoplasms is associated with changes in the expression of small non-coding RNAs (miRNAs). This emphasises the need for research into the development of miRNA-targeted inhibitors as a promising approach to cancer treatment.AIM. This study aimed to compare current strategies for suppressing the functional activity of tumour-associated miRNAs based on the use of therapeutic nucleic acids and to determine the application potential of these strategies.DISCUSSION. This study analysed known oligonucleotide-based miRNA inhibitors with different mechanisms of action. Based on their mechanism of action, miRNA-targeted inhibitors can be classified into two groups. The first group of miRNA-targeted inhibitors exhibits an indirect inhibitory effect, either by blocking functional connections between miRNAs and specific mRNA targets through the use of miRNA-masking oligonucleotides or by introducing mutations into miRNA genes and disrupting gene biosynthesis processes through the use of the CRISPR/Cas system. Despite their relatively high biological potential, these strategies are mostly used as search tools to study miRNA functional roles and molecular interactions in carcinogenesis. The second group of oligonucleotide constructs interacts with miRNA targets directly, which leads to steric blocking or degradation of oncogenic microRNAs. These miRNA-binding oligonucleotide constructs come in a variety of structural variants, including miRNA sponges, RNA zippers, antisense oligonucleotides, and miRNases, which demonstrate high therapeutic potential in vitro and in vivo.CONCLUSION. The described analysis of the biological properties, therapeutic potential, and key advantages of the developed miRNA-targeted oligonucleotide constructs helps outline the areas for their potential practical application in cancer treatment.

MicroRNA-194 regulates parasitic load and IL-1β-dependent nitric oxide production in the peripheral blood mononuclear cells of dogs with leishmaniasis.

Domestic dogs are the primary urban reservoirs of Leishmania infantum, the causative agent of visceral leishmaniasis. In Canine Leishmaniasis (CanL), modulation of the host's immune response may be associated with the expression of small non-coding RNAs called microRNA (miR). miR-194 expression increases in peripheral blood mononuclear cells (PBMCs) of dogs with leishmaniasis with a positive correlation with the parasite load and in silico analysis demonstrated that the TRAF6 gene is the target of miR-194 in PBMCs from diseased dogs. Here, we isolated PBMCs from 5 healthy dogs and 28 dogs with leishmaniasis, naturally infected with L. infantum. To confirm changes in miR-194 and TRAF6 expression, basal expression of miR-194 and gene expression of TRAF6 was measured using qPCR. PBMCs from healthy dogs and dogs with leishmaniasis were transfected with miR-194 scramble, mimic, and inhibitor and cultured at 37° C, 5% CO2 for 48 hours. The expression of possible targets was measured: iNOS, NO, T-bet, GATA3, and FoxP3 were measured using flow cytometry; the production of cytokines IL-1β, IL-4, IL-6, IL-10, TNF-α, IFN-γ, and TGF-β in cell culture supernatants was measured using capture enzyme-linked immunosorbent assays (ELISA). Parasite load was measured using cytometry and qPCR. Functional assays followed by miR-194 inhibitor and IL-1β blockade and assessment of NO production were also performed. Basal miR-194 expression was increased in PBMC from dogs with Leishmaniasis and was negatively correlated with TRAF6 expression. The mimic of miR-194 promoted an increase in parasite load. There were no significant changes in T-bet, GATA3, or FoxP3 expression with miR-194 enhancement or inhibition. Inhibition of miR-194 increased IL-1β and NO in PBMCs from diseased dogs, and blockade of IL-1β following miR-194 inhibition decreased NO levels. These findings suggest that miR-194 is upregulated in PBMCs from dogs with leishmaniasis and increases parasite load, possibly decreasing NO production via IL-1β. These results increase our understanding of the mechanisms of evasion of the immune response by the parasite and the identification of possible therapeutic targets.

The Effects of Environmental Exposure on Epigenetic Modifications in Allergic Diseases.

Allergic diseases are one of the most common chronic conditions and their prevalence is on the rise. Environmental exposure, primarily prenatal and early life influences, affect the risk for the development and specific phenotypes of allergic diseases via epigenetic mechanisms. Exposure to pollutants, microorganisms and parasites, tobacco smoke and certain aspects of diet are known to drive epigenetic changes that are essential for immune regulation (e.g., the shift toward T helper 2-Th2 cell polarization and decrease in regulatory T-cell (Treg) differentiation). DNA methylation and histone modifications can modify immune programming related to either pro-allergic interleukin 4 (IL-4), interleukin 13 (IL-13) or counter-regulatory interferon γ (IFN-γ) production. Differential expression of small non-coding RNAs has also been linked to the risk for allergic diseases and associated with air pollution. Certain exposures and associated epigenetic mechanisms play a role in the susceptibility to allergic conditions and specific clinical manifestations of the disease, while others are thought to have a protective role against the development of allergic diseases, such as maternal and early postnatal microbial diversity, maternal helminth infections and dietary supplementation with polyunsaturated fatty acids and vitamin D. Epigenetic mechanisms are also known to be involved in mediating the response to common treatment in allergic diseases, for example, changes in histone acetylation of proinflammatory genes and in the expression of certain microRNAs are associated with the response to inhaled corticosteroids in asthma. Gaining better insight into the epigenetic regulation of allergic diseases may ultimately lead to significant improvements in the management of these conditions, earlier and more precise diagnostics, optimization of current treatment regimes, and the implementation of novel therapeutic options and prevention strategies in the near future.

Maternal restricted- and over- feeding during gestation perturb offspring sperm epigenome in sheep.

Inadequate maternal nutrition during gestation can have immediate and lifelong effects on offspring. This study shows that maternal restricted - and over- nutrition during gestation do not affect semen characteristics in F1 male offspring but alters offspring sperm sncRNA profiles and DNA methylome in sheep. There is a growing body of evidence that inadequate maternal nutrition during gestation can have immediate and lifelong effects on offspring. However, little is known about the effects of maternal nutrition during gestation on male offspring reproduction. Here, using a sheep model of maternal restricted - and over - nutrition (60 or 140% of the National Research Council requirements) during gestation, we found that maternal restricted - and over - nutrition do not affect semen characteristics (i.e. volume, sperm concentration, pH, sperm motility, sperm morphology) or scrotal circumference in male F1 offspring. However, using small RNA sequencing analysis, we demonstrated that both restricted - and over - nutrition during gestation induced marked changes in composition and expression of sperm small noncoding RNAs (sncRNAs) subpopulations including in male F1 offspring. Whole-genome bisulfite sequencing analysis further identified specific genomic loci where poor maternal nutrition resulted in alterations in DNA methylation. These findings indicate that maternal restricted - and over - nutrition during gestation induce epigenetic modifications in sperm of F1 offspring sperm in sheep, which may contribute to environmentally influenced phenotypes in ruminants.

O-061 Single cell atlas of small RNAs in the human preimplantation embryo reveals the miRNA dynamics of lineage segregation

Abstract Study question How does the small non-coding RNA (sncRNA) expression profile of the human embryo change from day three (E3) to seven (E7) of preimplantation development? Summary answer From E3 to E7, micro-RNA expression becomes more dynamic, targeting genes important for lineage segregation. What is known already The drivers of lineage specification [SP1] in the human embryo remain unknown. SncRNAs regulate gene expression in most biological systems studied to date, with critical roles in cell development, differentiation, and disease. The most well-studied class of sncRNA, micro-RNAs (miRNAs), are required for embryo development to the peri-implantation stage in animal models, and their expression regulates embryonic stem cell differentiation in vitro. Study design, size, duration Eighty-seven E3-E5 embryos donated for research to the CReATe Fertility Centre (Veritas IRB#16580) between 2002 and 2021 were thawed and cultured to E3-E7. A total of 1279 cells were profiled for sncRNAs. Of these, 463 had known gender and 189 cells were co-sequenced for their mRNA complement. Participants/materials, setting, methods Good-quality embryos by morphology were enzymatically and mechanically dissociated into single cells and subjected to small and large RNA sequencing, as outlined in Petropoulos et al. 2016 and Hagemann-Jensen et al. 2018. Gene expression was analyzed with the ‘Seurat’ package. MiRNA targeting and pathway analysis was performed with Mienturnet. Main results and the role of chance We identified the complete complement of small RNAs present in the human preimplantation embryo, with piRNAs being the most abundant in E3 and miRNAs increasing in diversity and abundance to E7. Uniform Manifold Approximation and Projection (UMAP) analysis revealed progression with developmental stage and lineage. Split-cell co-sequencing identified canonical transcriptional markers of preimplantation development, allowing the classification of the small RNA profiles of 16-cell, early blast, inner cell mass (ICM), mural TE, and polar TE populations. Enriched miRNAs in the E5 ICM included miR-302b-5p and miR-302c-3p, which have known functions in stem cell programming. Conversely, TE cells were enriched for miR-519b-3p, miR-519c-3p, and miR-516a-5p, all members of the imprinted primate-specific microRNA gene cluster (C19MC), which is required for placenta formation. Targeting analysis identified miRNA-gene networks involving the Hedgehog, Hippo, and FoxO signalling pathways, all of which are developmentally significant. Limitations, reasons for caution This study was performed on embryos from a single center – embryo handling and culture conditions may influence sncRNA expression. Furthermore, the ability of these embryos to implant was unknown, therefore we likely profiled some non-viable embryos. Wider implications of the findings The epigenomic changes which drive lineage segregation are poorly understood, and there are vast differences in embryonic development between conventional model systems and humans. We report the first sncRNA profile of single cells between human E3 and E7, providing a resource for further exploration of their role in preimplantation development. Trial registration number not applicable

Seminal extracellular vesicle sncRNA sequencing reveals altered miRNA/isomiR profiles as sperm retrieval biomarkers for azoospermia.

Non-invasive molecular biomarkers for classifying azoospermia by origin into either obstructive or non-obstructive/secretory azoospermia, as well as for inferring the spermatogenic reserve of the testis of non-obstructive/secretory azoospermia patients, are of great interest for testicular sperm retrieval outcome prediction for assisted reproduction. Prior analyses of semen small non-coding RNA expression in azoospermia have focused on microRNAs, but there has been a lack of attention on other regulatory small RNA species. In this regard, studying more in-depth expression changes of small non-coding RNA subtypes in small extracellular vesicles from semen of azoospermic individuals could be useful to select additional non-invasive biomarkers with diagnostic/prognostic purposes. A high-throughput small RNA profiling analysis to determine the expression pattern of seminal small extracellular vesicle microRNAs (analyzed at the isomiR level), PIWI-interacting RNAs, and transfer RNA-derived small RNAs in normozoospermic (n = 4) and azoospermic (obstructive azoospermia because of pathological occurring obstruction in the genital tract, n = 4; secretory azoospermic individuals with positive testicular sperm extraction value, n = 5; secretory azoospermic individuals with negative testicular sperm extraction value, n = 4) individuals was carried out. Reverse transcriptase-quantitative real-time polymerase chain reaction validation analysis of selected microRNAs was additionally performed in a larger number of individuals. Clinically relevant quantitative changes in the small non-coding RNA levels contained in semen small extracellular vesicles can be used as biomarkers for the origin of azoospermia and for predicting the presence of residual spermatogenesis. In this regard, canonical isoform microRNAs (n = 185) but also other isomiR variants (n = 238) stand out in terms of numbers and fold-change differences in expression, underlining the need to consider isomiRs when investigating microRNA-based regulation. Conversely, although transfer RNA-derived small RNAs are shown in our study to represent a high proportion of small non-coding RNA sequences in seminal small extracellular vesicle samples, they are not able to discriminate the origin of azoospermia. PIWI-interacting RNA cluster profiles and individual PIWI-interacting RNAs with significant differential expression were also not able to discriminate. Our study demonstrated that expression values of individual and/or combined canonical isoform microRNAs (miR-10a-5p, miR-146a-5p, miR-31-5p, miR-181b-5p; area under the receiver operating characteristic curve >0.8) in small extracellular vesicles provide considerable clinical value in identifying samples with a high likelihood of sperm retrieval while discriminating azoospermia by origin. Although no individual microRNA showed sufficient discriminating power on its own to identify severe spermatogenic disorders with focal spermatogenesis, multivariate microRNA models in semen small extracellular vesicles have the potential to identify those individuals with residual spermatogenesis. Availability and adoption of such non-invasive molecular biomarkers would represent a great improvement in reproductive treatment decision protocols for azoospermia in clinical practice.

MiR-150 regulates the Leishmania infantum parasitic load and granzyme B levels in peripheral blood mononuclear cells of dogs with canine visceral leishmaniosis

Leishmania infantum causes visceral leishmaniosis, a neglected tropical disease that can modulate the host immune response by altering the expression of small non-coding RNAs called microRNAs (miRNAs). Some miRNAs are differentially expressed in peripheral blood mononuclear cells (PBMCs) of dogs with canine visceral leishmaniosis (CanL), like the down-regulated miR-150. Even though miR-150 is negatively correlated with L. infantum parasitic load, it is unclear if miR-150 directly affects L. infantum parasitic load and (if so) how this miRNA would contribute to infection. Here, we isolated PBMCs from 14 naturally infected dogs (CanL group) and six healthy dogs (Control group) and treated them in vitro with miR-150 mimic or inhibitor. We measured L. infantum parasitic load using qPCR and compared treatments. We also measured miR-150 in silico predicted target protein levels (STAT1, TNF-α, HDAC8, and GZMB) using flow cytometry or enzyme-linked immunosorbent assays. Increasing miR-150 activity diminished L. infantum parasitic load in CanL PBMCs. We also found that inhibition of miR-150 reduced GZMB (granzyme B) levels. These findings demonstrate that miR-150 plays an important role in L. infantum infection in canine PBMCs, and they merit further studies aiming at drug development.

Comparative Expression Profiling Reveals Molecular Markers Involved in the Progression of Cutaneous Melanoma towards Metastasis

Cutaneous melanoma is one of the most aggressive types of cancer and often proves fatal in metastatic stages. Few treatment options are available, and its global incidence is quickly increasing. In order to gain an improved understanding of the molecular features regarding melanoma progression, we have compared gene and small non-coding RNA expression profiles from cell lines derived from primary melanoma (MelJuSo), lymph node metastasis (MNT-1) and brain metastasis (VMM1), representing distinct stages of malignant progression. Our preliminary results highlighted the aberrant regulation of molecular markers involved in several processes that aid melanoma progression and metastasis development, including extracellular matrix remodeling, migratory potential and angiogenesis. Moreover, bioinformatic analysis revealed potential targets of the microRNAs of interest. Confocal microscopy and immunohistochemistry analysis were used for validation at the protein level. Exploring the molecular landscape of melanoma may contribute to the achievement of future efficient targeted therapy, as well as better prevention, diagnosis and clinical management.

Loss of dyskerin facilitates the acquisition of metastatic traits by altering the mevalonate pathway.

The initial dissemination of cancer cells from many primary tumors implies intravasation to lymphatic nodes or blood vessels. To investigate the mechanisms involved, we analyzed the expression of small non-coding RNAs in cutaneous squamous cell carcinoma (cSCC), a prevalent tumor that mainly spreads to lymph nodes. We report the reduced expression of small nucleolar RNAs in primary cSCCs that metastasized when compared to non-metastasizing cSCCs, and the progressive loss of DKC1 (dyskerin, which stabilizes the small nucleolar RNAs) along the metastasis. DKC1 depletion in cSCC cells triggered lipid metabolism by altering the mevalonate pathway and the acquisition of metastatic traits. Treatment of DKC1-depleted cells with simvastatin, an inhibitor of the mevalonate pathway, blocked the expression of proteins involved in the epithelial-to-mesenchymal transition. Consistently, the expression of the enzyme 3-hydroxy-3-methylglutaryl-CoA synthase 1 was associated with pathological features of high metastatic risk in cSCC patients. Our data underpin the relevance of the mevalonate metabolism in metastatic dissemination and pave the possible incorporation of therapeutic approaches among the antineoplastic drugs used in routine patient care.

Diagnostic and Prognostic Value of microRNAs in Patients with Laryngeal Cancer: A Systematic Review.

Laryngeal squamous cell cancer (LSCC) is one of the most common malignant tumors of the head and neck region, with a poor survival rate (5-year overall survival 50-80%) as a consequence of an advanced-stage diagnosis and high recurrence rate. Tobacco smoking and alcohol abuse are the main risk factors of LSCC development. An early diagnosis of LSCC, a prompt detection of recurrence and a more precise monitoring of the efficacy of different treatment modalities are currently needed to reduce the mortality. Therefore, the identification of effective diagnostic and prognostic biomarkers for LSCC is crucial to guide disease management and improve clinical outcomes. In the past years, a dysregulated expression of small non-coding RNAs, including microRNAs (miRNAs), has been reported in many human cancers, including LSCC, and many miRNAs have been explored for their diagnostic and prognostic potential and proposed as biomarkers. We searched electronic databases for original papers that were focused on miRNAs and LSCC, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. According to the outcome, 566 articles were initially screened, of which 177 studies were selected and included in the analysis. In this systematic review, we provide an overview of the current literature on the function and the potential diagnostic and prognostic role of tissue and circulating miRNAs in LSCC.

Human YRNA 4 (HY4) plasma levels are a prognostic indicator of SARS-CoV-2 infection clinical severity.

SARS-CoV-2 infection can result in a range of outcomes from asymptomatic/mild disease to severe COVID-19/fatality. In this study, we investigated the differential expression of small noncoding RNAs (sncRNAs) between patient cohorts defined by disease severity. We collected plasma samples, stratified these based on clinical outcomes, and sequenced their circulating sncRNAs. Excitingly, we found YRNA HY4 displays significant differential expression (p=0.025) between patients experiencing mild and severe disease. In agreement with recent reports identifying plasma YRNAs as indicators of influenza infection severity, our results strongly suggest that circulating HY4 levels represent a powerful prognostic indicator of likely SARS-CoV-2 patient infection outcome.

Investigation of Relationship Between Small Noncoding RNA (sncRNA) Expression Levels and Serum Iron, Copper, and Zinc Levels in Clinical Diagnosed Multiple Sclerosis Patients.

In our study, we aimed to investigate the relationship between microRNA (miRNA) expression levels and serum iron (Fe), copper (Cu), and zinc (Zn) levels in Multiple sclerosis (MS) patients. Total RNA was isolated from peripheral venous blood containing ethylenediaminetetraacetic acid (EDTA) of MS patients and controls. Total RNA was labeled with Cy3-CTP fluorescent dye. Hybridization of samples was performed on microarray slides and arrays were scanned. Data argument and bioinformatics analysis were performed. Atomic absorption spectrophotometer method was used to measure serum Fe, Cu, and Zn levels. In our study, in bioinformatics analysis, although differently expressed miRNAs were not detected between 16 MS patients and 16 controls, hsa-miR-744-5p upregulation was detected between 4 MS patients and 4 controls. This may be stem from the patient group consisting of MS patients who have never had an attack for 1year. Serum iron levels were detected significantly higher in the 16 MS patients compared to the 16 controls. This may be stem from the increase in iron accumulation based on inflammation in MS disease. According to the findings in our study, hsa-miR-744-5p upregulation has been determined as an early diagnostic biomarker for the development together of insulin resistance, diabetes mellitus associated with insulin signaling, and Alzheimer's diseases. Therefore, hsa-miR-744-5p is recommended as an important biomarker for the development together of diabetes mellitus, Alzheimer's disease, and MS disease. In addition, increased serum Fe levels may be suggested as an important biomarker for neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and MS disease.

Small non-coding RNA sequencing reveals global dysregulation of piwi-interacting RNA (piRNA) expression in gonadal malignant germ cell tumours.

Analyses of small non-coding RNA (ncRNA) expression in malignant germ cell tumours (GCTs) have focused on microRNAs (miRNAs). As GCTs all arise from primordial germ cells, and piwi-interacting RNAs (piRNAs) have important roles in maintaining germline integrity via transposon silencing, we hypothesised that malignant GCTs are characterised by fundamental piRNA dysregulation. We undertook global small ncRNA sequencing in malignant GCTs, in order to describe small ncRNA expression changes for both miRNAs and piRNAs. We performed small ncRNA next generation sequencing on a representative panel of 47 samples, comprising malignant GCT (n=31) and control (n=16) tissues/cell lines. Following quality control and normalisation, filtered count reads were used for differential miRNA and piRNA expression analyses via DESeq2. Predicted mRNA targets for piRNAs were identified and utilised for pathway enrichment analyses. Overall, miRNAs and piRNAs comprised 21.9% and 43.0% of small ncRNA species, respectively. There were 749 differentially expressed miRNAs in malignant GCTs, of which 536 (72%) were over-expressed and 213 (28%) under-expressed. The top-ranking over-expressed miRNAs were exclusively from the miR-371∼373 and miR-302/367 clusters. The most significantly under-expressed miRNAs were miR-100-5p, miR-214-3p, miR-125b-5p and let-7 family members, including miR-202-3p. There were 1,121 differentially expressed piRNAs in malignant GCTs, of which 167 (15%) were over-expressed and 954 (85%) under-expressed. Of note, of the top-20 differentially expressed piRNAs, 16 were over-expressed, of which piR-hsa-2506793 was both top-ranking and most abundant. Mobile element (ME; i.e., transposon)-associated piRNAs comprised 166 (15%) of the 1,121 differentially expressed piRNAs, of which 165 (>99%) were down-regulated. The remaining 955 (85%) non-ME-associated piRNAs may have wider cellular roles. To explore this, predicted mRNA targets of differentially expressed piRNAs identified putative involvement in cancer-associated pathways. This study confirms previous miRNA observations, giving credence to our novel demonstration of global piRNA dysregulation in gonadal malignant GCTs, through both ME and non-ME-associated pathways, which likely contributes to GCT pathogenesis.

Small and long RNA transcriptome of whole human cerebrospinal fluid and serum as compared to their extracellular vesicle fractions reveal profound differences in expression patterns and impacts on biological processes

BackgroundNext generation sequencing (NGS) of human specimen is expected to improve prognosis and diagnosis of human diseases, but its sensitivity urges for well-defined sampling and standardized protocols in order to avoid error-prone conclusions.MethodsIn this study, large volumes of pooled human cerebrospinal fluid (CSF) were used to prepare RNA from human CSF-derived extracellular vesicles (EV) and from whole CSF, as well as from whole human serum and serum-derived EV. In all four fractions small and long coding and non-coding RNA expression was analyzed with NGS and transcriptome analyses.ResultsWe show, that the source of sampling has a large impact on the acquired NGS pattern, and differences between small RNA fractions are more distinct than differences between long RNA fractions. The highest percentual discrepancy between small RNA fractions and the second highest difference between long RNA fractions is seen in the comparison of CSF-derived EV and whole CSF. Differences between miR (microRNA) and mRNA fractions of EV and the respective whole body fluid have the potential to affect different cellular and biological processes. I.e. a comparison of miR in both CSF fractions reveals that miR from EV target four transcripts sets involved in neurobiological processes, whereas eight others, also involved in neurobiological processes are targeted by miR found in whole CSF only. Likewise, three mRNAs sets derived from CSF-derived EV are associated with neurobiological and six sets with mitochondrial metabolism, whereas no such mRNA transcript sets are found in the whole CSF fraction. We show that trace amounts of blood-derived contaminations of CSF can bias RNA-based CSF diagnostics.ConclusionsThis study shows that the composition of small and long RNA differ significantly between whole body fluid and its respective EV fraction and thus can affect different cellular and molecular functions. Trace amounts of blood-derived contaminations of CSF can bias CSF analysis. This has to be considered for a meaningful RNA-based diagnostics. Our data imply a transport of EV from serum to CSF across the blood–brain barrier.

Small non-coding RNA landscape of extracellular vesicles from a post-traumatic model of equine osteoarthritis.

Extracellular vesicles comprise an as yet inadequately investigated intercellular communication pathway in the field of early osteoarthritis. We hypothesised that the small non-coding RNA expression pattern in synovial fluid and plasma would change during progression of experimental osteoarthritis. In this study, we conducted small RNA sequencing to provide a comprehensive overview of the temporal expression profiles of small non-coding transcripts carried by extracellular vesicles derived from plasma and synovial fluid for the first time in a posttraumatic model of equine osteoarthritis. Additionally, we characterised synovial fluid and plasma-derived extracellular vesicles with respect to quantity, size, and surface markers. The different temporal expressions of seven microRNAs in plasma and synovial fluid-derived extracellular vesicles, eca-miR-451, eca-miR-25, eca-miR-215, eca-miR-92a, eca-miR-let-7c, eca-miR-486-5p, and eca-miR-23a, and four snoRNAs, U3, snord15, snord46, and snord58, represent potential biomarkers for early osteoarthritis. Bioinformatics analysis of the differentially expressed microRNAs in synovial fluid highlighted that in early osteoarthritis these related to the inhibition of cell cycle, cell cycle progression, DNA damage and cell proliferation as well as increased cell viability and differentiation of stem cells. Plasma and synovial fluid-derived extracellular vesicle small non-coding signatures have been established for the first time in a temporal model of osteoarthritis. These could serve as novel biomarkers for evaluation of osteoarthritis progression or act as potential therapeutic targets.

Changes in Small Noncoding RNA Expression during Chondrocyte Senescence.

ObjectiveOsteoarthritis (OA) is characterized by the chronic and progressive deterioration of articular cartilage. Chondrocyte senescence could lead to a shift in the balance between extracellular matrix (ECM) component synthesis and degradation. Small noncoding RNAs (sncRNAs), including microRNAs (miRNAs), P-element-induced wimpy testis-(PIWI-) interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), small nuclear RNAs (snRNAs), and repeat-associated siRNAs (rasiRNAs), are a class of important epigenetic molecules. We aimed to gain insights into the changes and roles of sncRNA in chondrocyte senescence.DesignHealthy mouse postnatal chondrocytes were isolated, and a replicative aging model was constructed. We used small RNA sequencing (small RNA-seq) to generate extensive small RNA data. We identified differentially expressed sncRNAs and performed tissue-specific analysis using real-time quantitative polymerase chain reaction (qRT-PCR). β-galactosidase staining was used to detect chondrocyte senescence. The results showed that the expression profiles of sncRNA in passage 5 chondrocytes were significantly different from those in passage 0 chondrocytes. The expression of sncRNA was tissue specific. We found that 40 miRNAs were upregulated and 70 miRNAs were downregulated during chondrocyte senescence, and that miR-132-5p expression inhibition prevented chondrocyte senescence. We found that 8 piRNAs were upregulated and 17 piRNAs were downregulated during chondrocyte senescence, and that piRNA piR_025576 overexpression delayed chondrocyte senescence. We found that 24 snoRNAs were upregulated and 28 snoRNAs were downregulated during chondrocyte senescence, and that snoRNA ENSMUSG00000087935 overexpression delayed chondrocyte senescence. We found that 5 snRNAs were upregulated and 6 snRNAs were downregulated during chondrocyte senescence, and that snRNA ENSMUSG00000064682 overexpression delayed chondrocyte senescence. We found that 1 rasiRNA was upregulated and 4 rasiRNAs were downregulated during chondrocyte senescence.ConclusionsThese findings might provide novel insights into OA pathogenesis and contribute to the development of candidates for targeted therapeutics in OA.

The Use of Pro-Angiogenic and/or Pro-Hypoxic miRNAs as Tools to Monitor Patients with Diffuse Gliomas.

IDH (isocitrate dehydrogenase) mutation, hypoxia, and neo-angiogenesis, three hallmarks of diffuse gliomas, modulate the expression of small non-coding RNAs (miRNA). In this paper, we tested whether pro-angiogenic and/or pro-hypoxic miRNAs could be used to monitor patients with glioma. The miRNAs were extracted from tumoral surgical specimens embedded in the paraffin of 97 patients with diffuse gliomas and, for 7 patients, from a blood sample too. The expression of 10 pro-angiogenic and/or pro-hypoxic miRNAs was assayed by qRT-PCR and normalized to the miRNA expression of non-tumoral brain tissues. We confirmed in vitro that IDH in hypoxia (1% O2, 24 h) alters pro-angiogenic and/or pro-hypoxic miRNA expression in HBT-14 (U-87 MG) cells. Then, we reported that the expression of these miRNAs is (i) strongly affected in patients with glioma compared to that in a non-tumoral brain; (ii) correlated with the histology/grade of glioma according to the 2016 WHO classification; and (iii) predicts the overall and/or progression-free survival of patients with glioma in univariate but not in a multivariate analysis after adjusting for sex, age at diagnosis, and WHO classification. Finally, the expression of miRNAs was found to be the same between the plasma and glial tumor of the same patient. This study highlights a panel of seven pro-angiogenic and/or pro-hypoxic miRNAs as a potential tool for monitoring patients with glioma.

Small Non-Coding RNAs in Leukemia.

Simple SummaryLeukemia is a group of blood cancers that arise when abnormal or underdeveloped blood cells accumulate in the bloodstream, bone marrow and lymphatic system. A driver event in the development of Chronic Lymphocytic Leukemia (CLL) is the deletion of the genomic region encoding for miR-15a/16-1. MicroRNAs are small non-coding RNAs involved in the regulation of gene expression, and loss of miR-15a/16-1 in CLL results in the accumulation of the antiapoptotic gene BCL2 and inhibition of the apoptotic process. This discovery was the first evidence that microRNAs have a role in the onset of cancer. Following this finding, several studies investigated the role of microRNAs and other small non-coding RNAs in different types of leukemia and cancers in general. This review summarizes the role of small non-coding RNAs in leukemia and describes their possible application in clinical settings as biomarkers and/or targets for therapy. In 2020, more than 60,500 people were diagnosed with leukemia in the USA, and more than 23,000 died. The incidence of leukemia is still rising, and drug resistance development is a serious concern for patients’ wellbeing and survival. In the past two decades, small non-coding RNAs have been studied to evaluate their functions and possible role in cancer pathogenesis. Small non-coding RNAs are short RNA molecules involved in several cellular processes by regulating the expression of genes. An increasing body of evidence collected by many independent studies shows that the expression of these molecules is tissue specific, and that their dysregulation alters the expression of genes involved in tumor development, progression and drug response. Indeed, small non-coding RNAs play a pivotal role in the onset, staging, relapse and drug response of hematological malignancies and cancers in general. These findings strongly suggest that small non-coding RNAs could function as biomarkers and possible targets for therapy. Thus, in this review, we summarize the regulatory mechanisms of small non-coding RNA expression in different types of leukemia and assess their potential clinical implications.