Requirement of bic/microRNA-155 for normal immune function

The impact of miRNA-155 in acute and chronic toxoplasmosis in Iraqi women

Toxoplasmosis is a prevalent parasitic infection caused by Toxoplasma gondii known to induce complex immune responses, to control the infection. MicroRNAs (miRNAs) are a cluster of small noncoding RNAs that are reported to have regulatory functions in the immune response. The objective of this study is to assess the expression of miR-155 and its targets, Src homology-2 domain-containing inositol 5- phosphatase 1 (SHIP-1) and suppressor of cytokine signaling-1 (SOCS1), in non-pregnant Iraqi women seropositive for toxoplasmosis. The study included 55 non-pregnant women positive for toxoplasmosis (20 in the acute phase and 35 in the chronic phase) and 35 non-pregnant women negative for toxoplasmosis (control group). Serum samples were collected from all participants to investigate the expression of miR-155 by RT‒PCR, in addition to the levels of SOCS1 and SHIP-1 measured by ELISA. The results showed a significant increase in the expression of miR-155 in both groups of acute and chronic toxoplasmosis compared to the control group. Lower levels of SOCS1 and SHIP-1 were found in acutely infected women compared to those with chronic infection and non-infected women. These findings showed the possible critical impact of miR-155 on host immune response during T.gondii infection, proposing that miR-155 can be explored as a prospective target to support host immune response against infectious diseases, with special help in early detection and management of toxoplasmosis in high-risk immunocompromised patients. Further studies are needed to evaluate the molecular pathways by which miRNAs improve immunity against toxoplasmosis.

Detection of MicroRNA-155 Based on Lambda Exonuclease Selective Digestion and CRISPR/Cas12a-assisted Amplification

In numerous malignancies, miRNA-155 is overexpressed and has oncogenic activity because it is one of the most efficient microRNAs for inhibiting apoptosis in human cancer cells. As a result, the highest sensitive detection of the miRNA-155 gene is a technological instrument that can enable early cancer screening. In this study, a miRNA-155 biosensor was created to create a hairpin probe that can bind to the miRNA-155 gene using lambda nucleic acid exonuclease, which can cut the 5' phosphorylated double strand, and by the DNA probe is recognized by the Cas12a enzyme, which then activates Cas12a to catalyze trans-cutting produces strong fluorescence. Research finding, the target concentration's logarithm and corresponding fluorescence intensity have a strong linear connection, and the limit of detection (LOD) of the sensing system was determined to be 8.3 pM. In addition, the biosensor displayed exceptional specificity, low false-positive signal, and high sensitivity in detecting the miRNA-155 gene in serum samples. This study's creation of a biosensor that has high sensitivity, good selectivity, and is simple to operate provides promising opportunities for research into biosensor design and early cancer detection.

Let-7 restrains an oncogenic epigenetic circuit in AT2 cells to prevent ectopic formation of fibrogenic transitional cell intermediates and pulmonary fibrosis

Analysis of lung alveolar type 2 (AT2) progenitor stem cells has highlighted fundamental mechanisms that direct their differentiation into alveolar type 1 cells (AT1s) in lung repair and disease. However, microRNA (miRNA) mediated post-transcriptional mechanisms which govern this nexus remain understudied. We show here that the let-7 miRNA family serves a homeostatic role in governance of AT2 quiescence, specifically by preventing the uncontrolled accumulation of AT2 transitional cells and by promoting AT1 differentiation to safeguard the lung from spontaneous alveolar destruction and fibrosis. Using mice and organoid models with genetic ablation of let-7a1/let-7f1/let-7d cluster (let-7afd) in AT2 cells, we demonstrate prevents AT1 differentiation and results in aberrant accumulation of AT2 transitional cells in progressive pulmonary fibrosis. Integration of enhanced AGO2 UV-crosslinking and immunoprecipitation sequencing (AGO2-eCLIP) with RNA-sequencing from AT2 cells uncovered the induction of direct targets of let-7 in an oncogene feed-forward regulatory network including BACH1/EZH2 which drives an aberrant fibrotic cascade. Additional analyses by CUT&RUN-sequencing revealed loss of let-7afd hampers AT1 differentiation by eliciting aberrant histone EZH2 methylation which prevents the exit of AT2 transitional cells into terminal AT1s. This study identifies let-7 as a key gatekeeper of post-transcriptional and epigenetic chromatin signals to prevent AT2-driven pulmonary fibrosis.

Non-coding RNAs to treat vascular smooth muscle cell dysfunction

Vascular smooth muscle cell (vSMC) dysfunction is a critical contributor to cardiovascular diseases, including atherosclerosis, restenosis and vein graft failure. Recent advances have unveiled a fascinating range of non-coding RNAs (ncRNAs) that play a pivotal role in regulating vSMC function. This review aims to provide an in-depth analysis of the mechanisms underlying vSMC dysfunction and the therapeutic potential of various ncRNAs in mitigating this dysfunction, either preventing or reversing it. We explore the intricate interplay of microRNAs, long-non-coding RNAs and circular RNAs, shedding light on their roles in regulating key signalling pathways associated with vSMC dysfunction. We also discuss the prospects and challenges associated with developing ncRNA-based therapies for this prevalent type of cardiovascular pathology.

Noncanonical microprotein regulation of immunity

The immune system is highly regulated but, when dysregulated, suboptimal protective or overly robust immune responses can lead to immune-mediated disorders. The genetic and molecular mechanisms of immune regulation are incompletely understood, impeding the development of more precise diagnostics and therapeutics for immune-mediated disorders. Recently, thousands of previously unrecognized noncanonical microprotein genes encoded by small open reading frames have been identified. Many of these microproteins perform critical functions, often in a cell- and context-specific manner. Several microproteins are now known to regulate immunity; however, the vast majority are uncharacterized. Therefore, illuminating what is often referred to as the "dark proteome," may present opportunities to tune immune responses more precisely. Here, we review noncanonical microprotein biology, highlight recently discovered examples regulating immunity, and discuss the potential and challenges of modulating dysregulated immune responses by targeting microproteins.

Non-coding RNAs in exercise immunology: A systematic review

Regular physical exercise has been recognized as a potent modulator of immune function, with its effects including enhanced immune surveillance, reduced inflammation, and improved overall health. While strong evidence exists that physical exercise affects the specific expression and activity of non-coding RNAs (ncRNAs) also involved in immune system regulation, heterogeneity in individual study designs and analyzed exercise protocols exists, and a condensed list of functional, exercise-dependent ncRNAs with known targets in the immune system is missing from the literature. A systematic review and qualitative analysis was used to identify and categorize ncRNAs participating in immune modulation by physical exercise. Two combined approaches were used: (a) a systematic literature search for "ncRNA and exercise immunology", (b) and a database search for microRNAs (miRNAs) (miRTarBase and DIANA-Tarbase v8) aligned with known target genes in the immune system based on the Reactome database, combined with a systematic literature search for "ncRNA and exercise". Literature searches were based on PubMed, Web of Science, and SPORTDiscus; and miRNA databases were filtered for targets validated by in vitro experimental data. Studies were eligible if they reported on exercise-based interventions in healthy humans. After duplicate removal, 95 studies were included reporting on 164 miRNAs, which were used for the qualitative synthesis. Six studies reporting on long-noncoding RNAs (lncRNAs) or circular RNAs were also identified. Results were analyzed using ordering tables that included exercise modality (endurance/resistance exercise), acute or chronic interventions, as well as the consistency in reported change between studies. Evaluation criteria were defined as "validated" with 100% of ≥3 independent studies showing identical direction of regulation, "plausible" (≥80%), or "suggestive" (≥70%). For resistance exercise, upregulation of miR-206 was validated while downregulation of miR-133a appeared plausible. For endurance exercise, 15 miRNAs were categorized as validated, with 12 miRNAs being consistently elevated and 3 miRNAs being downregulated, most of them after acute exercise training. In conclusion, our approach provides evidence that miRNAs play a major role in exercise-induced effects on the innate and adaptive immune system by targeting different pathways affecting immune cell distribution, function, and trafficking as well as production of (anti-)inflammatory cytokines. miRNAs miR-15, miR-29c, miR-30a, miR-142/3, miR-181a, and miR-338 emerged as key players in mediating the immunomodulatory effects of exercise predominantly after acute bouts of endurance exercise.

Noncoding RNAs in skeletal development and disorders

Protein-encoding genes only constitute less than 2% of total human genomic sequences, and 98% of genetic information was previously referred to as "junk DNA". Meanwhile, non-coding RNAs (ncRNAs) consist of approximately 60% of the transcriptional output of human cells. Thousands of ncRNAs have been identified in recent decades, and their essential roles in the regulation of gene expression in diverse cellular pathways associated with fundamental cell processes, including proliferation, differentiation, apoptosis, and metabolism, have been extensively investigated. Furthermore, the gene regulation networks they form modulate gene expression in normal development and under pathological conditions. In this review, we integrate current information about the classification, biogenesis, and function of ncRNAs and how these ncRNAs support skeletal development through their regulation of critical genes and signaling pathways in vivo. We also summarize the updated knowledge of ncRNAs involved in common skeletal diseases and disorders, including but not limited to osteoporosis, osteoarthritis, rheumatoid arthritis, scoliosis, and intervertebral disc degeneration, by highlighting their roles established from in vivo, in vitro, and ex vivo studies.

Extracellular vesicle miRNAs drive aberrant macrophage responses in NSAID-exacerbated respiratory disease

BACKGROUND

Extracellular vesicles (EVs) have been implicated in the pathogenesis of asthma, however, how EVs contribute to immune dysfunction and type 2 airway inflammation remains incompletely understood. We aimed to elucidate roles of airway EVs and their miRNA cargo in the pathogenesis of NSAID-exacerbated respiratory disease (N-ERD), a severe type 2 inflammatory condition.

METHODS

EVs were isolated from induced sputum or supernatants of cultured nasal polyp or turbinate tissues of N-ERD patients or healthy controls by size-exclusion chromatography and characterized by particle tracking, electron microscopy and miRNA sequencing. Functional effects of EV miRNAs on gene expression and mediator release by human macrophages or normal human bronchial epithelial cells (NHBEs) were studied by RNA sequencing, LC-MS/MS and multiplex cytokine assays.

RESULTS

EVs were highly abundant in secretions from the upper and lower airways of N-ERD patients. N-ERD airway EVs displayed profoundly altered immunostimulatory capacities and miRNA profiles compared to airway EVs of healthy individuals. Airway EVs of N-ERD patients, but not of healthy individuals induced inflammatory cytokine (GM-CSF and IL-8) production by NHBEs. In macrophages, N-ERD airway EVs exhibited an impaired potential to induce cytokine and prostanoid production, while enhancing M2 macrophage activation. Let-7 family miRNAs were highly enriched in sputum EVs from N-ERD patients and mimicked suppressive effects of N-ERD EVs on macrophage activation.

CONCLUSION

Aberrant airway EV miRNA profiles may contribute to immune dysfunction and chronic type 2 inflammation in N-ERD. Let-7 family miRNAs represent targets for correcting aberrant macrophage activation and mediator responses in N-ERD.

miRNA as potential biomarkers after liver transplantation: A systematic review

BACKGROUND

Liver transplantation is a life-saving therapy for end-stage liver disease patients, but acute cellular rejection (ACR) and graft complications remain significant postoperative challenges. Early and accurate diagnosis is crucial for timely intervention and improved patient outcomes, but their diagnosis rely currently on invasive biopsy sampling, thus prompting the search for non-invasive Biomarkers. MicroRNA (miRNA) have emerged as promising biomarkers in various pathological conditions, and their potential utility in diagnosing acute cellular rejection after liver transplantation has gained significant interest.

METHODS

This systematic review of PubMed, Web of Science, and the ClinicalTrials.gov registry analyzes studies exploring miRNA as biomarkers for ACR and graft dysfunction in liver transplantation (PROSPERO ID CRD42023465278). The Cochrane Collaboration tool for assessing risk of bias was employed. Population data, identified miRNA and their dynamic regulation, as well as event prediction were compared. Data extraction and quality assessment were performed independently by two reviewers.

RESULTS

Thirteen studies were included in this systematic review. Various investigated miRNAs were upregulated in association with acute cellular rejection, like miR-122, miR-155, miR-181, miR-483-3p, and miR-885-5p, demonstrating great biomarker potential. Additionally, several studies conducted target gene analysis, revealing insights into cellular mechanisms linked to ACR. Moreover, various miRNA were also capable of predicting different organ complications following transplantation, expanding their versatility. Remaining challenges include the standardization of miRNA profiling, the need for functional validation, and the necessity for long-term studies.

CONCLUSION

The results highlight the potential of miRNA as specific, non-invasive biomarkers for ACR and graft dysfunction following liver transplantation. However, further research is needed to validate these findings and establish standardized diagnostic panels to incorporate them into clinical practice and explore miRNA-based therapies in the future.

microRNA-1 regulates sea urchin skeletogenesis by directly targeting skeletogenic genes and modulating components of signaling pathways

microRNAs are evolutionarily conserved non-coding RNAs that direct post-transcriptional regulation of target transcripts. In vertebrates, microRNA-1 (miR-1) is expressed in muscle and has been found to play critical regulatory roles in vertebrate angiogenesis, a process that has been proposed to be analogous to sea urchin skeletogenesis. Results indicate that both miR-1 inhibitor and miR-1 mimic-injected larvae have significantly less F-actin enriched circumpharyngeal muscle fibers and fewer gut contractions. In addition, miR-1 regulates the positioning of skeletogenic primary mesenchyme cells (PMCs) and skeletogenesis of the sea urchin embryo. Interestingly, the gain-of-function of miR-1 leads to more severe PMC patterning and skeletal branching defects than its loss-of-function. The results suggest that miR-1 directly suppresses Ets1/2, Tbr, and VegfR7 of the skeletogenic gene regulatory network, and Nodal, and Wnt1 signaling components. This study identifies potential targets of miR-1 that impacts skeletogenesis and muscle formation and contributes to a deeper understanding of miR-1's function during development.

MicroRNA-155 mediates multiple gene regulations pertinent to the role of human adipose-derived mesenchymal stem cells in skin regeneration

Introduction: The role of Adipose-derived mesenchymal stem cells (AD-MSCs) in skin wound healing remains to be fully characterized. This study aims to evaluate the regenerative potential of autologous AD-MSCs in a non-healing porcine wound model, in addition to elucidate key miRNA-mediated epigenetic regulations that underlie the regenerative potential of AD-MSCs in wounds. Methods: The regenerative potential of autologous AD-MSCs was evaluated in porcine model using histopathology and spatial frequency domain imaging. Then, the correlations between miRNAs and proteins of AD-MSCs were evaluated using an integration analysis in primary human AD-MSCs in comparison to primary human keratinocytes. Transfection study of AD-MSCs was conducted to validate the bioinformatics data. Results: Autologous porcine AD-MSCs improved wound epithelialization and skin properties in comparison to control wounds. We identified 26 proteins upregulated in human AD-MSCs, including growth and angiogenic factors, chemokines and inflammatory cytokines. Pathway enrichment analysis highlighted cell signalling-associated pathways and immunomodulatory pathways. miRNA-target modelling revealed regulations related to genes encoding for 16 upregulated proteins. miR-155-5p was predicted to regulate Fibroblast growth factor 2 and 7, C-C motif chemokine ligand 2 and Vascular cell adhesion molecule 1. Transfecting human AD-MSCs cell line with anti-miR-155 showed transient gene silencing of the four proteins at 24 h post-transfection. Discussion: This study proposes a positive miR-155-mediated gene regulation of key factors involved in wound healing. The study represents a promising approach for miRNA-based and cell-free regenerative treatment for difficult-to-heal wounds. The therapeutic potential of miR-155 and its identified targets should be further explored in-vivo.

Influence of a pro-inflammatory stimulus on the miRNA and lipid content of human dental stem cell-derived extracellular vesicles and their impact on microglial activation

Neuro-inflammation occurs in numerous disorders such as multiple sclerosis, Alzheimer's disease and Parkinson's disease. However, anti-inflammatory drugs for the central nervous system have failed to show significant improvement when compared to a placebo in clinical trials. Our previous work demonstrated that stem cells from the apical papilla (SCAP) can decrease neuro-inflammation and stimulate oligodendrocyte progenitor cell differentiation. One hypothesis is that the therapeutic effect of SCAP could be mediated by their secretome, including extracellular vesicles (EV). Here, our objectives were to characterize SCAP-EV and to study their effect on microglial cells. We isolated EV from non-activated SCAP and from SCAP activated with TNFα and IFN-γ and characterized them according to their size, EV markers, miRNA and lipid content. Their ability to decrease pro-inflammatory cytokine expression in vitro and ex vivo was also assessed. We showed that the miRNA content was impacted by a pro-inflammatory environment but not their lipid composition. SCAP-EV reduced the expression of pro-inflammatory markers in LPS-activated microglial cells while their effect was limited on mouse spinal cord sections. In conclusion, we were able to isolate EV from SCAP, to show that their miRNA content was impacted by a pro-inflammatory stimulus, and to describe that SCAP-EV and not the protein fraction of conditioned medium could reduce pro-inflammatory marker expression in LPS-activated BV2 cells.

InflammamiRs in focus: Delivery strategies and therapeutic approaches

microRNAs (miRNAs) are small non-protein-coding RNAs which are essential regulators of host genome expression at the post-transcriptional level. There is evidence of dysregulated miRNA expression patterns in a wide variety of diseases, such as autoimmune and inflammatory conditions. These miRNAs have been termed "inflammamiRs." When working with miRNAs, the method followed, the approach to treat or diagnosis, and the selected biological material are very crucial. Demonstration of the role of miRNAs in particular disease phenotypes facilitates their evaluation as potential and effective therapeutic tools. A growing number of reports suggest the significant utility of miRNAs and other small RNA drugs in clinical medicine. Most miRNAs seem promising therapeutic options, but some features associated with miRNA therapy like off-target effect, effective dosage, or differential delivery methods, mainly caused by the short target's sequence, make miRNA therapies challenging. In this review, we aim to discuss some of the inflammamiRs in diseases associated with inflammatory pathways and the challenge of identifying the most potent therapeutic candidates and provide a perspective on achieving safe and targeted delivery of miRNA therapeutics. We also discuss the status of inflammamiRs in clinical trials.

Metabolic disorders affecting the liver and heart: Therapeutic efficacy of miRNA-based therapies?

Liver and heart disease are major causes of death worldwide. It is known that metabolic alteration causing type 2 diabetes (T2D) and Nonalcoholic fatty liver (NAFLD) coupled with a derangement in lipid homeostasis, may exacerbate hepatic and cardiovascular diseases. Some pharmacological treatments can mitigate organ dysfunctions but the important side effects limit their efficacy leading often to deterioration of the tissues. It needs to develop new personalized treatment approaches and recent progresses of engineered RNA molecules are becoming increasingly viable as alternative treatments. This review outlines the current use of antisense oligonucleotides (ASOs), RNA interference (RNAi) and RNA genome editing as treatment for rare metabolic disorders. However, the potential for small non-coding RNAs to serve as therapeutic agents for liver and heart diseases is yet to be fully explored. Although miRNAs are recognized as biomarkers for many diseases, they are also capable of serving as drugs for medical intervention; several clinical trials are testing miRNAs as therapeutics for type 2 diabetes, nonalcoholic fatty liver as well as cardiac diseases. Recent advances in RNA-based therapeutics may potentially facilitate a novel application of miRNAs as agents and as druggable targets. In this work, we sought to summarize the advancement and advantages of miRNA selective therapy when compared to conventional drugs. In particular, we sought to emphasise druggable miRNAs, over ASOs or other RNA therapeutics or conventional drugs. Finally, we sought to address research questions related to efficacy, side-effects, and range of use of RNA therapeutics. Additionally, we covered hurdles and examined recent advances in the use of miRNA-based RNA therapy in metabolic disorders such as diabetes, liver, and heart diseases.

Lead exposure is related to higher infection rate with the gapeworm in Norwegian house sparrows (Passer domesticus)

Anthropogenic pollution is identified as an important threat to bird and other wildlife populations. Many metals and toxic elements, along with poly- and perfluoroalkyl substances (PFASs) are known to induce immunomodulation and have previously been linked to increased pathogen prevalence and infectious disease severity. In this study, the house sparrow (Passer domesticus) was investigated at the coast of Helgeland in northern Norway. This population is commonly infected with the parasitic nematode "gapeworm" (Syngamus trachea), with a prevalence of 40-60 % during summer months. Gapeworm induces severe respiratory disease in birds and has been previously demonstrated to decrease survival and reproductive success in wild house sparrows. The aim of this study was to investigate whether a higher exposure to pollution with PFASs, metals and other elements influences gapeworm infection in wild house sparrows. We conducted PFASs and elemental analysis on whole blood from 52 house sparrows from Helgeland, including analyses of highly toxic metals such as lead (Pb), mercury (Hg) and arsenic (As). In addition, we studied gapeworm infection load by counting the parasite eggs in faeces from each individual. We also studied the expression of microRNA 155 (miR155) as a key regulator in the immune system. Elevated blood concentrations of Pb were found to be associated with an increased prevalence of gapeworm infection in the house sparrow. The expression of miR155 in the plasma of the house sparrow was only weakly associated with Pb. In contrast, we found relatively low PFASs concentrations in the house sparrow blood (∑ PFASs 0.00048-354 μg/L) and PFASs were not associated to miR155 nor infection rate. The current study highlights the potential threat posed by Pb as an immunotoxic pollutant in small songbirds.

CRISPR/Cas9 deletion of MIR155HG in human T cells reduces incidence and severity of acute GVHD in a xenogeneic model

ABSTRACT

Acute graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic cell transplantation (allo-HCT). Using preclinical mouse models of disease, previous work in our laboratory has linked microRNA-155 (miR-155) to the development of acute GVHD. Transplantation of donor T cells from miR-155 host gene (MIR155HG) knockout mice prevented acute GVHD in multiple murine models of disease while maintaining critical graft-versus-leukemia (GVL) response, necessary for relapse prevention. In this study, we used clustered, regularly interspaced, short palindromic repeats (CRISPR)/Cas9 genome editing to delete miR-155 in primary T cells (MIR155HGΔexon3) from human donors, resulting in stable and sustained reduction in expression of miR-155. Using the xenogeneic model of acute GVHD, we show that NOD/SCID/IL2rγnull (NSG) mice receiving MIR155HGΔexon3 human T cells provide protection from lethal acute GVHD compared with mice that received human T cells with intact miR-155. MIR155HGΔexon3 human T cells persist in the recipients displaying decreased proliferation potential, reduced pathogenic T helper-1 cell population, and infiltration into GVHD target organs, such as the liver and skin. Importantly, MIR155HGΔexon3 human T cells retain GVL response significantly improving survival in an in vivo model of xeno-GVL. Altogether, we show that CRISPR/Cas9-mediated deletion of MIR155HG in primary human donor T cells is an innovative approach to generate allogeneic donor T cells that provide protection from lethal GVHD while maintaining robust antileukemic response.

MiR-155 promotes compensatory lung growth by inhibiting JARID2 activation of CD34+ endothelial progenitor cells

Bone marrow-derived CD34-positive (CD34+) endothelial progenitor cells (EPCs) has unique functions in the mechanism of compensatory lung growth (CLG). The content of this study is mainly to describe the effect of microRNA (miR)-155 in the mechanisms of EPCs and CLG. Our study found that transfection of miR-155 mimic could promote EPC proliferation, migration and tube formation, while transfection of miR-155 inhibitor had the opposite effect. It was also found that transfection of pc-JARID2 inhibited EPC proliferation, migration and tube formation, while transfection of si-JARID2 had the opposite effect. miR-155 can target and negatively regulate JARID2 expression. Overexpression of JARID2 weakened the promoting effects of miR-155 mimic on EPC proliferation, migration, and tubular formation, while silencing JARID2 weakened the inhibitory effects of miR-155 inhibitors on EPC proliferation, migration, and tubular formation. Transplantation of EPCs transfected with miR-155 mimic into the left lung model effectively increased lung volume, total alveolar number, diaphragm surface area, and lung endothelial cell number, while transplantation of EPCs co-transfected with miR-155 mimic and pc-JARID2 reversed this phenomenon. Overall, we found that miR-155 activates CD34+ EPC by targeting negative regulation of JARID2 and promotes CLG.

Serum microRNA Profiles and Pathways in Hepatitis B-Associated Hepatocellular Carcinoma: A South African Study

The incidence and mortality of hepatocellular carcinoma (HCC) in Sub-Saharan Africa is projected to increase sharply by 2040 against a backdrop of limited diagnostic and therapeutic options. Two large South African-based case control studies have developed a serum-based miRNome for Hepatitis B-associated hepatocellular carcinoma (HBV-HCC), as well as identifying their gene targets and pathways. Using a combination of RNA sequencing, differential analysis and filters including a unique molecular index count (UMI) ≥ 10 and log fold change (LFC) range > 2: <-0.5 (p < 0.05), 91 dysregulated miRNAs were characterized including 30 that were upregulated and 61 were downregulated. KEGG analysis, a literature review and other bioinformatic tools identified the targeted genes and HBV-HCC pathways of the top 10 most dysregulated miRNAs. The results, which are based on differentiating miRNA expression of cases versus controls, also develop a serum-based miRNA diagnostic panel that indicates 95.9% sensitivity, 91.0% specificity and a Youden Index of 0.869. In conclusion, the results develop a comprehensive African HBV-HCC miRNome that potentially can contribute to RNA-based diagnostic and therapeutic options.

Challenges and promise of targeting miRNA in rheumatic diseases: a computational approach to identify miRNA association with cell types, cytokines, and disease mechanisms

MicroRNAs (miRNAs) are small non-coding RNAs that alter the expression of target genes at the post-transcriptional level, influencing diverse outcomes in metabolism, cell differentiation, proliferation, cell survival, and cell death. Dysregulated miRNA expression is implicated in various rheumatic conditions, including ankylosing spondylitis (AS), gout, juvenile idiopathic arthritis (JIA), osteoarthritis (OA), psoriatic arthritis, rheumatoid arthritis (RA), Sjogren's syndrome, systemic lupus erythematosus (SLE) and systemic sclerosis. For this review, we used an open-source programming language- PowerShell, to scan the massive number of existing primary research publications on PubMed on miRNAs in these nine diseases to identify and count unique co-occurrences of individual miRNAs and the disease name. These counts were used to rank the top seven most relevant immuno-miRs based on their research volume in each rheumatic disease. Individual miRNAs were also screened for publication with the names of immune cells, cytokines, and pathological processes involved in rheumatic diseases. These occurrences were tabulated into matrices to identify hotspots for research relevance. Based on this information, we summarize the basic and clinical findings for the top three miRNAs - miR-146, miR-155, and miR-21 - whose relevance spans across multiple rheumatic diseases. Furthermore, we highlight some unique miRNAs for each disease and why some rheumatic conditions lack research in this emerging epigenetics field. With the overwhelming number of publications on miRNAs in rheumatic diseases, this review serves as a 'relevance finder' to guide researchers in selecting miRNAs based on the compiled existing knowledge of their involvement in disease pathogenesis. This approach applies to other disease contexts with the end goal of developing miRNA-based therapeutics.

Pharmacogenomic and epigenomic approaches to untangle the enigma of IL-10 blockade in oncology

The host immune system status remains an unresolved mystery among several malignancies. An immune-compromised state or smart immune-surveillance tactics orchestrated by cancer cells are the primary cause of cancer invasion and metastasis. Taking a closer look at the tumour-immune microenvironment, a complex network and crosstalk between infiltrating immune cells and cancer cells mediated by cytokines, chemokines, exosomal mediators and shed ligands are present. Cytokines such as interleukins can influence all components of the tumour microenvironment (TME), consequently promoting or suppressing tumour invasion based on their secreting source. Interleukin-10 (IL-10) is an interlocked cytokine that has been associated with several types of malignancies and proved to have paradoxical effects. IL-10 has multiple functions on cellular and non-cellular components within the TME. In this review, the authors shed the light on the regulatory role of IL-10 in the TME of several malignant contexts. Moreover, detailed epigenomic and pharmacogenomic approaches for the regulation of IL-10 were presented and discussed.

Profiling salivary miRNA expression levels in Fanconi anemia patients - a pilot study

The overarching goal of this study is to predict the risk of developing oral squamous cell carcinoma (OSCC) in Fanconi anemia (FA) patients. We have compared the microRNA (miRNA, miR) expression levels in saliva samples from FA patients (n = 50) who are at a low-moderate and/or high risk of developing OSCC to saliva samples from healthy controls (n = 16). The miRNA expression levels in saliva samples were quantified using qPCR. We observed that miR-744, miR-150-5P, and miR-146B-5P had the best discriminatory capacity between FA patients and controls, with an area under the curve (AUC) of 94.0%, 92.9% and 85.3%, respectively. Our data suggest that miR-1, miR-146B-5P, miR-150-5P, miR-155-5P, and miR-744 could be used as panel to predict the risk of developing OSCC in FA patients, with a 89.3% sensitivity and a 68.2% specificity (AUC = 81.5%). Our preliminary data support the notion that the expression levels of salivary miRNAs have the potential to predict the risk of developing OSCC in FA patients and in the future may reduce deaths associated with OSCC.

Considering potential roles of selected MicroRNAs in evaluating subclinical mastitis and Milk quality in California mastitis test (+) and infected bovine milk

This study investigates the relationships between subclinical mastitis and milk quality with selected microRNAs in cow milk. California Mastitis Test (CMT)-positive (n = 20) and negative (n = 20) samples were compared (Experiment I). Additionally, samples with CMT-positive but microbiological-negative, as well as positive for only Staphylococcus subspecies (Staph spp.) and only Streptococcus subspecies (Strep spp.) were examined (Experiment II). Four groups were formed in Experiment II: Group I (CMT and microbiological-negative) (n = 20), Group II (CMT-positive but microbiological-negative) (n = 10), Group III (Staph spp.) (n = 5), Group IV (Strep spp.) (n = 5). While electrical conductivity, somatic cell count (SCC), malondialdehyde (MDA) increased, miR-27a-3p and miR-223 upregulated and miR-125b downregulated in the CMT-positive group in Experiment I. SCC and MDA were higher in CMT-positive groups. miR-27a-3p and miR-223 upregulated in Groups III and IV. While miR-155 is upregulated, miR-125b downregulated in Group IV. Milk fat is positively correlated with miR-148a and miR-223. As miR-27a-3p positively correlated with SCC and MDA, miR-125b negatively correlated with electrical conductivity and SCC. miR-148a and MDA were positively correlated. miR-155 was correlated with fat-free dry matter, protein, lactose, and freezing point. miR-223 was positively correlated with SCC and miR-148a. Results particularly highlight miR-27a-3p and miR-223 as potential biomarkers in subclinical mastitis, especially those caused by Staph spp. and Strep spp., while miR-148a, miR-155, and miR-223 stand out in determining milk quality.

Global blood miRNA profiling unravels early signatures of immunogenicity of Ebola vaccine rVSVΔG-ZEBOV-GP

The vectored Ebola vaccine rVSVΔG-ZEBOV-GP elicits protection against Ebola Virus Disease (EVD). In a study of forty-eight healthy adult volunteers who received either the rVSVΔG-ZEBOV-GP vaccine or placebo, we profiled intracellular microRNAs (miRNAs) from whole blood cells (WB) and circulating miRNAs from serum-derived extracellular vesicles (EV) at baseline and longitudinally following vaccination. Further, we identified early miRNA signatures associated with ZEBOV-specific IgG antibody responses at baseline and up to one year post-vaccination, and pinpointed target mRNA transcripts and pathways correlated to miRNAs whose expression was altered after vaccination by using systems biology approaches. Several miRNAs were differentially expressed (DE) and miRNA signatures predicted high or low IgG ZEBOV-specific antibody levels with high classification performance. The top miRNA discriminators were WB-miR-6810, EV-miR-7151-3p, and EV-miR-4426. An eight-miRNA antibody predictive signature was associated with immune-related target mRNAs and pathways. These findings provide valuable insights into early blood biomarkers associated with rVSVΔG-ZEBOV-GP vaccine-induced IgG antibody responses.

miRNA Expression Profiling in Human Breast Cancer Diagnostics and Therapy

Breast cancer is one of the most commonly diagnosed cancer types worldwide. Regarding molecular characteristics and classification, it is a heterogeneous disease, which makes it more challenging to diagnose. As is commonly known, early detection plays a pivotal role in decreasing mortality and providing a better prognosis for all patients. Different treatment strategies can be adjusted based on tumor progression and molecular characteristics, including personalized therapies. However, dealing with resistance to drugs and recurrence is a challenge. The therapeutic options are limited and can still lead to poor clinical outcomes. This review aims to shed light on the current perspective on the role of miRNAs in breast cancer diagnostics, characteristics, and prognosis. We discuss the potential role of selected non-coding RNAs most commonly associated with breast cancer. These include miR-21, miR-106a, miR-155, miR-141, let-7c, miR-335, miR-126, miR-199a, miR-101, and miR-9, which are perceived as potential biomarkers in breast cancer prognosis, diagnostics, and treatment response monitoring. As miRNAs differ in expression levels in different types of cancer, they may provide novel cancer therapy strategies. However, some limitations regarding dynamic alterations, tissue-specific profiles, and detection methods must also be raised.

Epi-microRNA mediated metabolic reprogramming ensures affinity maturation

To increase antibody affinity against pathogens, positively selected GC-B cells initiate cell division in the light zone (LZ) of germinal centres (GCs). Among those, higher-affinity clones migrate to the dark zone (DZ) and vigorously proliferate by relying on oxidative phosphorylation (OXPHOS). However, it remains unknown how positively selected GC-B cells adapt their metabolism for cell division in the glycolysis-dominant, cell cycle arrest-inducing, hypoxic LZ microenvironment. Here, we show that microRNA (miR)-155 mediates metabolic reprogramming during positive selection to protect high-affinity clones. Transcriptome examination and mass spectrometry analysis revealed that miR-155 regulates H3K36me2 levels by directly repressing hypoxia-induced histone lysine demethylase, Kdm2a. This is indispensable for enhancing OXPHOS through optimizing the expression of vital nuclear mitochondrial genes under hypoxia. The miR-155-Kdm2a interaction is crucial to prevent excessive production of reactive oxygen species and apoptosis. Thus, miR-155-mediated epigenetic regulation promotes mitochondrial fitness in high-affinity clones, ensuring their expansion and consequently affinity maturation.

The role of miRNAs in Behçet's disease

The symptoms of Behçet's disease (BD), a multisystemic condition with autoimmune and inflammation as hallmarks, include arthritis, recurring oral and vaginal ulcers, skin rashes and lesions, and involvement of the nervous, gastrointestinal, and vascular systems. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), may be important regulators of inflammation and autoimmune disease. These ncRNAs are essential to the physiological and pathophysiological disease course, and miRNA in particular has received significant attention for its role and function in BD and its potential use as a diagnostic biomarker in recent years. Although promising as therapeutic targets, miRNAs must be studied further to fully comprehend how miRNAs in BD act biologically.

MicroRNA-155 and cancer metastasis: Regulation of invasion, migration, and epithelial-to-mesenchymal transition

Among the leading causes of death globally has been cancer. Nearly 90% of all cancer-related fatalities are attributed to metastasis, which is the growing of additional malignant growths out of the original cancer origin. Therefore, a significant clinical need for a deeper comprehension of metastasis exists. Beginning investigations are being made on the function of microRNAs (miRNAs) in the metastatic process. Tiny non-coding RNAs called miRNAs have a crucial part in controlling the spread of cancer. Some miRNAs regulate migration, invasion, colonization, cancer stem cells' properties, the epithelial-mesenchymal transition (EMT), and the microenvironment, among other processes, to either promote or prevent metastasis. One of the most well-conserved and versatile miRNAs, miR-155 is primarily distinguished by overexpression in a variety of illnesses, including malignant tumors. It has been discovered that altered miR-155 expression is connected to a number of physiological and pathological processes, including metastasis. As a result, miR-155-mediated signaling pathways were identified as possible cancer molecular therapy targets. The current research on miR-155, which is important in controlling cancer cells' invasion, and metastasis as well as migration, will be summarized in the current work. The crucial significance of the lncRNA/circRNA-miR-155-mRNA network as a crucial regulator of carcinogenesis and a player in the regulation of signaling pathways or related genes implicated in cancer metastasis will be covered in the final section. These might provide light on the creation of fresh treatment plans for controlling cancer metastasis.

Leveraging microRNAs for cellular therapy

Owing to Karl Landsteiner's discovery of blood groups, blood transfusions became safe cellular therapies in the early 1900s. Since then, cellular therapy made great advances from transfusions with unmodified cells to today's commercially available chimeric antigen receptor (CAR) T cells requiring complex manufacturing. Modern cellular therapy products can be improved using basic knowledge of cell biology and molecular genetics. Emerging genome engineering tools are becoming ever more versatile and precise and thus catalyze rapid progress towards programmable therapeutic cells that compute input and respond with defined output. Despite a large body of literature describing important functions of non-coding RNAs including microRNAs (miRNAs), the vast majority of cell engineering efforts focuses on proteins. However, miRNAs form an important layer of posttranscriptional regulation of gene expression. Here, we highlight examples of how miRNAs can successfully be incorporated into engineered cellular therapies.

Targeted microRNA delivery by lipid nanoparticles and gas vesicle-assisted ultrasound cavitation to treat heart transplant rejection

Despite exquisite immune response modulation, the extensive application of microRNA therapy in treating heart transplant rejection is still impeded by poor stability and low target efficiency. Here we have developed a low-intensity pulsed ultrasound (LIPUS) cavitation-assisted genetic therapy after executing the heart transplantation (LIGHT) strategy, facilitating microRNA delivery to target tissues through the LIPUS cavitation of gas vesicles (GVs), a class of air-filled protein nanostructures. We prepared antagomir-155 encapsulated liposome nanoparticles to enhance the stability. Then the murine heterotopic transplantation model was established, and antagomir-155 was delivered to murine allografted hearts via the cavitation of GVs agitated by LIPUS, which reinforced the target efficiency while guaranteeing safety owing to the specific acoustic property of GVs. This LIGHT strategy significantly depleted miR-155, upregulating the suppressors of cytokine signaling 1 (SOCS1), leading to reparative polarization of macrophages, decrease of T lymphocytes and reduction of inflammatory factors. Thereby, rejection was attenuated and the allografted heart survival was markedly prolonged. The LIGHT strategy achieves targeted delivery of microRNA with minimal invasiveness and great efficiency, paving the way towards novel ultrasound cavitation-assisted strategies of targeted genetic therapy for heart transplantation rejection.

The Role of MicroRNA in Graft-Versus-Host-Disease: A Review

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a clinically challenging modality for the treatment of many hematologic diseases such as leukemia, lymphoma, and myeloma. Graft-versus-host disease (GVHD) is a common complication after allo-HSCT and remains a major cause of morbidity and mortality, limiting the success of a potentially curative transplant. Several microRNAs (miRNAs) have recently been shown to impact the biology of GVHD. They are molecular regulators involved in numerous processes during T-cell development, homeostasis, and activation, and contribute to the pathological function of T-cells during GvHD. Here, we review the key role of miRNAs contributing to the GvHD; their detection might be an interesting possibility in the early diagnosis and monitoring of disease.

The miR-17∼92 miRNAs promote plasma cell differentiation by suppressing SOCS3-mediated NIK degradation

The miR-17∼92 family microRNAs (miRNAs) play a key role in germinal center (GC) reaction through promoting T follicular helper (TFH) cell differentiation. It remains unclear whether they also have intrinsic functions in B cell differentiation and function. Here we show that mice with B cell-specific deletion of the miR-17∼92 family exhibit impaired GC reaction, plasma cell differentiation, and antibody production in response to protein antigen immunization and chronic viral infection. Employing CRISPR-mediated functional screening, we identify Socs3 as a key functional target of miR-17∼92 in regulating plasma cell differentiation. Mechanistically, SOCS3, whose expression is elevated in miR-17∼92 family-deficient B cells, interacts with NIK and promotes its ubiquitination and degradation, thereby impairing NF-κB signaling and plasma cell differentiation. This moderate increase in SOCS3 expression has little effect on IL-21-STAT3 signaling. Our study demonstrates differential sensitivity of two key signaling pathways to alterations in the protein level of an miRNA target gene.

Role of microRNAs in Chronic Lymphocytic Leukemia

Chronic Lymphocytic Leukemia (CLL) is the most common form of leukemia in adults, with a highly variable clinical course. Improvement in the knowledge of the molecular pathways behind this disease has led to the development of increasingly specific therapies, such as BCR signaling inhibitors and BCL-2 inhibitors. In this context, the emerging role of microRNAs (miRNAs) in CLL pathophysiology and their possible application in therapy is worth noting. MiRNAs are one of the most important regulatory molecules of gene expression. In CLL, they can act both as oncogenes and tumor suppressor genes, and the deregulation of specific miRNAs has been associated with prognosis, progression, and drug resistance. In this review, we describe the role of the miRNAs that primarily impact the disease, and how these miRNAs could be used as therapeutic tools. Certainly, the use of miRNAs in clinical practice is still limited in CLL. Many issues still need to be solved, particularly regarding their biological and safety profile, even if several studies have suggested their efficacy on the disease, alone or in combination with other drugs.

Post-transcriptional checkpoints in autoimmunity

Post-transcriptional regulation is a fundamental process in gene expression that has a role in diverse cellular processes, including immune responses. A core concept underlying post-transcriptional regulation is that protein abundance is not solely determined by transcript abundance. Indeed, transcription and translation are not directly coupled, and intervening steps occur between these processes, including the regulation of mRNA stability, localization and alternative splicing, which can impact protein abundance. These steps are controlled by various post-transcription factors such as RNA-binding proteins and non-coding RNAs, including microRNAs, and aberrant post-transcriptional regulation has been implicated in various pathological conditions. Indeed, studies on the pathogenesis of autoimmune and inflammatory diseases have identified various post-transcription factors as important regulators of immune cell-mediated and target effector cell-mediated pathological conditions. This Review summarizes current knowledge regarding the roles of post-transcriptional checkpoints in autoimmunity, as evidenced by studies in both haematopoietic and non-haematopoietic cells, and discusses the relevance of these findings for developing new anti-inflammatory therapies.

Peripheral Blood and Nasopharyngeal Swab MiRNA-155 Expression in Infants with Respiratory Syncytial Virus Infection

INTRODUCTION

MicroRNA (miR) 155 has been implicated in the regulation of innate and adaptive immunity as well as antiviral responses, but its role during respiratory syncytial virus (RSV) infections is not known. The objective of this study was to investigate the expression of miR-155 using pharyngeal swabs and peripheral blood in infants with RSV infection and uninfected controls.

METHODS

A prospective age-matched study was conducted in primary care in Torino from 1 August 2018 to 31 January 2020. We enrolled 66 subjects, 29 of them patients with RSV infection and 37 age-matched uninfected controls, and collected pharyngeal swabs and peripheral blood in order to assess miR-155 expression with real-time stem-loop-TaqMan real-time PCR.

RESULTS

The data show that there is no correlation between pharyngeal swabs and peripheral blood with respect to miR-155 expression. The 1/ΔCq miR-155 expression levels in throat swabs in RSV bronchiolitis patients and healthy controls were 0.19 ± 0.11 and 0.21 ± 0.09, respectively, and were not significantly different between healthy controls and bronchiolitis (p = 0.8414). In the peripheral blood, miR-155 levels were higher than those of healthy control subjects: 0.1 ± 0.013 and 0.09 ± 0.0007, respectively; p = 0.0002.

DISCUSSION

Our data provide evidence that miR-155 expression is higher in peripheral blood during RSV infection but not in swabs. This difference in the timing of sample recruitment could explain the differences obtained in the results; miR-155 activation is probably only assessable in the very early stages of infection in the swab and remains visible for longer in the blood. New investigations are needed in order to clarify whether the miR-155 expression in swabs can be influenced by different stages of virus disease of infants.

TGF-β Targeted by miR-27a Modulates Anti-Parasite Responses of Immune System

Background

Immune cells and their secreted cytokines are known as the first barrier against pathogens. Leishmania major as an intracellular protozoan produces anti-inflammatory cytokines that lead to proliferation and survival of the parasite in the macrophages. miRNAs are small non-coding RNA molecules that regulate mRNAs expression. We aimed to investigate the relationship between the expression of TGF-β and a bioinformatically candidate miRNA, in leishmaniasis as a model of TGF-β overexpression.

Methods

The miRNAs that target TGF-β -3'UTR were predicted and scored by bioinformatic tools. After cloning of TGF-β-3'UTR in psi-CHECK ™- 2 vector, targeting validation was confirmed using Luciferase assay. After miRNA mimic transfection, the expression of miR-27a, TGF-β, as well as Nitric Oxide concentration was evaluated.

Results

miR-27a received the highest score for targeting TGF-β in bioinformatic predictions. Luciferase assay confirmed that miR-27a is targeting TGF-β-3'UTR, since miR-27a transfection decreased the luciferase activity. After miRNA transfection, TGF-β expression and Nitric Oxide concentration were declined in L. major infected macrophages.

Conclusion

Bioinformatic prediction, luciferase assay, and miRNA transfection results showed that miR-27a targets TGF-β. Since miRNA and cytokine-base therapies are developing in infectious diseases, finding and validating miRNAs targeting regulatory cytokines can be a novel strategy for controlling and treating leishmaniasis.

The influence of COVID-19 on colorectal cancer was investigated using bioinformatics and systems biology techniques

Introduction

Coronavirus disease 2019 (COVID-19) is a global pandemic and highly contagious, posing a serious threat to human health. Colorectal cancer (CRC) is a risk factor for COVID-19 infection. Therefore, it is vital to investigate the intrinsic link between these two diseases.

Methods

In this work, bioinformatics and systems biology techniques were used to detect the mutual pathways, molecular biomarkers, and potential drugs between COVID-19 and CRC.

Results

A total of 161 common differentially expressed genes (DEGs) were identified based on the RNA sequencing datasets of the two diseases. Functional analysis was performed using ontology keywords, and pathway analysis was also performed. The common DEGs were further utilized to create a protein-protein interaction (PPI) network and to identify hub genes and key modules. The datasets revealed transcription factors-gene interactions, co-regulatory networks with DEGs-miRNAs of common DEGs, and predicted possible drugs as well. The ten predicted drugs include troglitazone, estradiol, progesterone, calcitriol, genistein, dexamethasone, lucanthone, resveratrol, retinoic acid, phorbol 12-myristate 13-acetate, some of which have been investigated as potential CRC and COVID-19 therapies.

Discussion

By clarifying the relationship between COVID-19 and CRC, we hope to provide novel clues and promising therapeutic drugs to treat these two illnesses.

Role of Extracellular microRNAs in Sepsis-Induced Acute Lung Injury

Acute lung injury (ALI) is a life-threatening pathological disease characterized by the damage of pulmonary endothelial cells and epithelial cell barriers by uncontrolled inflammation. During sepsis-induced ALI, multiple cells cooperate and communicate with each other to respond to the stimulation of inflammatory factors. However, the underlying mechanisms of action have not been fully identified, and the modes of communication therein are also being investigated. Extracellular vesicles (EVs) are a heterogeneous population of spherical membrane structures released by almost all types of cells, containing various cellular components. EVs are primary transport vehicles for microRNAs (miRNAs), which play essential roles in physiological and pathological processes in ALI. EV miRNAs from different sources participated in regulating the biological function of pulmonary epithelial cells, endothelial cells, and phagocytes by transferring miRNA through EVs during ALI induced by sepsis, which has great potential diagnostic and therapeutic values. This study aims to summarize the role and mechanism of extracellular vesicle miRNAs from different cells in the regulation of sepsis-induced ALI. It provides ideas for further exploring the role of extracellular miRNA secreted by different cells in the ALI induced by sepsis, to make up for the deficiency of current understanding, and to explore the more optimal scheme for diagnosis and treatment of ALI.

Air Pollution and microRNAs: The Role of Association in Airway Inflammation

Air pollution exposure plays a key role in the alteration of gene expression profiles, which can be regulated by microRNAs, inducing the development of various diseases. Moreover, there is also evidence of sensitivity of miRNAs to environmental factors, including tobacco smoke. Various diseases are related to specific microRNA signatures, suggesting their potential role in pathophysiological processes; considering their association with environmental pollutants, they could become novel biomarkers of exposure. Therefore, the aim of the present work is to analyse data reported in the literature on the role of environmental stressors on microRNA alterations and, in particular, to identify specific alterations that might be related to the development of airway diseases so as to propose future preventive, diagnostic, and therapeutic strategies.

The role of miRNA in colorectal cancer diagnosis: A pilot study

Despite recent advances in diagnosis and treatment, colorectal cancer (CRC) remains the third most common cancer worldwide, and has both a poor prognosis and a high recurrence rate, thus indicating the need for new, sensitive and specific biomarkers. MicroRNAs (miRNAs/miRs) are important regulators of gene expression, which are involved in numerous biological processes implicated in tumorigenesis. The objective of the present study was to investigate the expression of miRNAs in plasma and tissue samples from patients with CRC, and to examine their potential as CRC biomarkers. Using reverse transcription-quantitative PCR, it was revealed that miR-29a, miR-101, miR-125b, miR-146a and miR-155 were dysregulated in the formalin-fixed paraffin-embedded tissues of patients with CRC, compared with the surrounding healthy tissue, and these miRNAs were associated with several pathological features of the tumor. Bioinformatics analysis of overlapping target genes identified AGE-RAGE signaling as a putative joint regulatory pathway. miR-146a was also upregulated in the plasma of patients with CRC, compared with the healthy control group, and had a fair discriminatory power (area under the curve, 0.7006), with 66.7% sensitivity and 77.8% specificity. To the best of our knowledge, this distinct five-miRNA deregulation pattern in tumor tissue, and upregulation of plasma miR-146a, were shown for the first time in patients with CRC; however, studies on larger patient cohorts are warranted to confirm their potential to be used as CRC diagnostic biomarkers.

A plasmatic score using a miRNA signature and CXCL-10 for accurate prediction and diagnosis of liver allograft rejection

Introduction

The use of noninvasive biomarkers may avoid the need for liver biopsy (LB) and could guide immunosuppression adjustment in liver transplantation (LT). The aims of this study were: to confirm the predictive and diagnostic capacity of plasmatic expression of miR-155-5p, miR-181a-5p, miR-122-5p and CXCL-10 for assessing T-cell mediated rejection (TCMR) risk; to develop a score based on a panel of noninvasive biomarkers to predict graft rejection risk and to validate this score in a separate cohort.

Methods

A prospective, observational study was conducted with a cohort of 79 patients followed during the first year after LT. Plasma samples were collected at predetermined time points for the analysis of miRNAs and the CXCL-10. Patients with LFTs abnormalities were submitted to a LB to rule out rejection, assessing previous and concurrent expression of the biomarkers to evaluate their predictive and diagnostic ability. Information from 86 patients included in a previous study was collected and used as a validation cohort.

Results

Twenty-four rejection episodes were diagnosed in 22 patients. Plasmatic CXCL-10 concentration and the expression of the three miRNAs were significantly elevated prior to and at the moment of the diagnosis of rejection. We developed a logistic model for rejection prediction and diagnosis, which included CXCL-10, miR-155-5p and miR-181a-5p. The area under the ROC curve (AUROC) for rejection prediction was 0.975 (79.6% sensitivity, 99.1% specificity, 90,7% PPV; 97.7% NPV; 97.1% correctly classified) and 0.99 for diagnosis (87.5% sensitivity, 99.5% specificity, 91.3% PPV; 99.3% NPV; 98.9% correctly classified). In the validation cohort (n=86; 14 rejections), the same cut-off points were used obtaining AUROCs for rejection prediction and diagnosis of 0.89 and 0.92 respectively. In patients with graft dysfunction in both cohorts the score could discriminate those with rejection regarding other causes with an AUROC of 0.98 (97.3% sensitivity, 94.1%specificity).

Conclusion

These results suggest that the clinical implementation of the monitoring of this noninvasive plasmatic score may allow the prediction and diagnosis of rejection and identify patients with graft dysfunction due to rejection, helping with a more efficient guide for immunosuppressive therapy adjustment. This finding warrants the development of prospective biomarker-guided clinical trials.

Epigenetic modifications and obsessive-compulsive disorder: what do we know?

Obsessive-Compulsive Disorder (OCD) is a chronic, severe disabling neuropsychiatric disorder whose pathophysiology is not yet well defined. Generally, the symptom onset occurs during pre-adult life and affects subjects in different life aspects, including professional and social relationships. Although robust evidence indicates the presence of genetic factors in the etiopathology of OCD, the entirely mechanisms are not totally clarified. Thus, the possible interactions between genes and environmental risk factors mediated by epigenetic mechanisms should be sought. Therefore, we provide a review of genetic and epigenetic mechanisms related to OCD with a deep focus on the regulation of critical genes of the central nervous system seeking possible potential biomarkers.

miRNAs' Cross-Involvement in Skin Allergies: A New Horizon for the Pathogenesis, Diagnosis and Therapy of Atopic Dermatitis, Allergic Contact Dermatitis and Chronic Spontaneous Urticaria

Skin inflammation is a common underlying feature of atopic dermatitis, allergic contact dermatitis and chronic spontaneous urticaria. The pathogenetic mechanisms have not been fully elucidated. The purpose of this study was to examine whether miRNA, by regulating inflammatory mechanisms through the modulation of innate and adaptive immune responses, could play a major role in the pathogenesis of these skin conditions. We conducted a narrative review using the Pubmed and Embase scientific databases and search engines to find the most relevant miRNAs related to the pathophysiology, severity and prognosis of skin conditions. The studies show that miRNAs are involved in the pathogenesis and regulation of atopic dermatitis and can reveal an atopic predisposition or indicate disease severity. In chronic spontaneous urticaria, different miRNAs which are over-expressed during urticaria exacerbations not only play a role in the possible response to therapy or remission, but also serve as a marker of chronic autoimmune urticaria and indicate associations with other autoimmune diseases. In allergic contact dermatitis, miRNAs are upregulated in inflammatory lesions and expressed during the sensitization phase of allergic response. Several miRNAs have been identified as potential biomarkers of these chronic skin conditions, but they are also possible therapeutic targets.

Tumor-suppressive role of the musculoaponeurotic fibrosarcoma gene in colorectal cancer

Somatic cell reprogramming using the microRNAs miR-200c, miR-302s, and miR-369s leads to increased expression of cyclin-dependent kinase inhibitors in human colorectal cancer (CRC) cells and suppressed tumor growth. Here, we investigated whether these microRNAs inhibit colorectal tumorigenesis in CPC;Apc mice, which are prone to colon and rectal polyps. Repeated administration of microRNAs inhibited polyp formation. Microarray analysis indicated that c-MAF, which reportedly shows oncogene-like behavior in multiple myeloma and T cell lymphoma, decreased in tumor samples but increased in microRNA-treated normal mucosa. Immunohistochemistry identified downregulation of c-MAF as an early tumorigenesis event in CRC, with low c-MAF expression associated with poor prognosis. Of note, c-MAF expression and p53 protein levels were inversely correlated in CRC samples. c-MAF knockout led to enhanced tumor formation in azoxymethane/dextran sodium sulfate-treated mice, with activation of cancer-promoting genes. c-MAF may play a tumor-suppressive role in CRC development.

Integrated mRNA and miRNA expression analyses for Cryptocaryon irritans resistance in large yellow croaker (Larimichthys crocea)

Large yellow croaker (Larimichthys crocea) is one of the most important mariculture fish in China. However, cryptocaryonosis caused by Cryptocryon irritans infection has brought huge economic losses and threatened the healthy and sustainable development of L. crocea industry. Recently, a new C. irritans resistance strain of L. crocea (RS) has been bred using genomic selection technology in our laboratory work. However, the molecular mechanisms for C. irritans resistance of RS have not been fully understood. MicroRNAs (miRNAs) are endogenous small non-coding RNAs that are post-transcriptional regulators, and they play vital roles in immune process of bony fish. Identification of anti-C.irritans relevant miRNA signatures could, therefore, be of tremendous translational value. In the present study, integrated mRNA and miRNA expression analysis was used to explore C. irritans resistance mechanisms of the L. crocea. RS as well as a control strain (CS) of L. crocea, were artificially infected with C. irritans for 100 h, and their gill was collected at 0 h (pre-infection), 24 h (initial infection), and 72 h (peak infection) time points. The total RNA from gill tissues was extracted and used for transcriptome sequencing and small RNA sequencing. After sequencing, 23,172 known mRNAs and 289 known miRNAs were identified. The differential expression was analyzed in these mRNAs and mRNAs and the interactions of miRNA-mRNA pairs were constructed. KEGG pathway enrichment analyses showed that these putative target mRNAs of differentially expressed miRNAs (DEMs) were enriched in different immune-related pathways after C. irritans infection in RS and CS. Among them, necroptosis was the immune-related pathway that was only significantly enriched at two infection stages of RS group (RS-24 h/RS-0h and RS-72 h/RS-0h). Further investigation indicates that necroptosis may be activated by DEMs such as miR-133a-3p, miR-142a-3p and miR-135c, this promotes inflammation responses and pathogen elimination. These DEMs were selected as miRNAs that could potentially regulate the C. irritans resistance of L. crocea. Though these inferences need to be further verified, these findings will be helpful for the research of the molecular mechanism of C. irritans resistance of L. crocea and miRNA-assisted molecular breeding of aquatic animals.

MicroRNA-155 and Disease-Related Immunohistochemical Parameters in Cutaneous Melanoma

Cutaneous melanoma is a severe and life-threatening form of skin cancer with growing incidences. While novel interventions have improved prognoses for these patients, early diagnosis of targeted treatment remains the most effective approach. MicroRNAs have grown to good use as potential biomarkers for early detection and as targets for treatment. miR-155 is well-studied for its role in tumor cell survival and proliferation in various tissues, although its role in melanoma remains controversial. In silico data analysis was performed in the dbDEMC v.3 to identify differentially expressed miRNA. We validated gene targets in melanoma using TarBase v8.0 and miRPath v3.0 and determined protein-protein interactions of the target genes. One hundred forty patients (age range 21-90 years) with cutaneous melanoma who underwent resection were included. Molecular assessment using Real-Time RT-qPCR, clinicopathological associations, and a literature review for the different roles of miR-155 in melanoma were performed. Analysis of the dbDEMC reveals controversial findings. While there is evidence of upregulation of miR-155 in primary and metastatic melanoma samples, others suggest decreased expression in later-stage melanoma and cases with brain metastasis. miR-155 has been overexpressed in prior cases of melanoma and precancerous lesions, and it was found to be dysregulated when compared to benign nevi. While miR-155 expression was associated with favorable outcomes in some studies, others showed an association with metastasis. Patients with high levels of miR-155 also noted reduction after receiving anti-PD-1 treatment, correlated with more prolonged overall survival. In our patient's cohort, 22.9% relapsed during treatment, and 45% developed recurrence, associated with factors such as lymph node infiltration, high mitotic index, and positive staining for CD117. Although overall analysis revealed miR-155 downregulation in melanoma specimens compared to non-cancer tissues, increased expression of miR-155 was associated with cases of superficial spreading melanoma subtype (p = 0.005) and any melanoma with a high mitotic rate (p = 0.010). The analysis did not identify optimum cutoff values to predict relapse, recurrence, or mortality. In conclusion, miR-155 could have, in part, a potential prognostic utility in cutaneous melanoma. Further mechanistic studies are required to unravel the multifunctional role of miR-155 in melanoma.

Unravelling the tripartite interactions among Hepatitis E virus RNA, miR-140 and hnRNP K: Running title: Interactions between HEV-RNA, miR-140 and hnRNP K

In the present investigation, we have identified the functional significance of the highly conserved miR-140 binding site on the Hepatitis E Virus (HEV) genome. Multiple sequence alignment of the viral genome sequences along with RNA folding prediction indicated that the putative miR-140 binding site has significant conservation for sequence and secondary RNA structure among HEV genotypes. Site-directed mutagenesis and reporter assays indicated that an intact sequence of the miR-140 binding site is essential for HEV translation. Provision of mutant miR-140 oligos carrying same mutation as on mutant HEV successfully rescued mutant HEV replication. In vitro cell-based assays with modified oligos proved that host factor-miR-140 is a critical requirement for HEV replication. Biotinylated RNA pulldown and RNA immunoprecipitation assays proved that the predicted secondary RNA structure of the miR-140 binding site allows the recruitment of hnRNP K, which is a key protein of the HEV replication complex. We predicted the model from the obtained results that the miR-140 binding site can serve as a platform for recruitment of hnRNP K and other proteins of HEV replication complex only in the presence of miR-140.

Microglia specific deletion of miR-155 in Alzheimer's disease mouse models reduces amyloid-β pathology but causes hyperexcitability and seizures

Alzheimer's Disease (AD) is characterized by the accumulation of extracellular amyloid-β (Aβ) as well as CNS and systemic inflammation. Microglia, the myeloid cells resident in the CNS, use microRNAs to rapidly respond to inflammatory signals. MicroRNAs (miRNAs) modulate inflammatory responses in microglia, and miRNA profiles are altered in Alzheimer's disease (AD) patients. Expression of the pro-inflammatory miRNA, miR-155, is increased in the AD brain. However, the role of miR-155 in AD pathogenesis is not well-understood. We hypothesized that miR-155 participates in AD pathophysiology by regulating microglia internalization and degradation of Aβ. We used CX3CR1CreER/+ to drive-inducible, microglia-specific deletion of floxed miR-155 alleles in two AD mouse models. Microglia-specific inducible deletion of miR-155 in microglia increased anti-inflammatory gene expression while reducing insoluble Aβ1-42 and plaque area. Yet, microglia-specific miR-155 deletion led to early-onset hyperexcitability, recurring spontaneous seizures, and seizure-related mortality. The mechanism behind hyperexcitability involved microglia-mediated synaptic pruning as miR-155 deletion altered microglia internalization of synaptic material. These data identify miR-155 as a novel modulator of microglia Aβ internalization and synaptic pruning, influencing synaptic homeostasis in the setting of AD pathology.

Crosstalk of Transcriptional Regulators of Adaptive Immune System and microRNAs: An Insight into Differentiation and Development

MicroRNAs (miRNAs), as small regulatory RNA molecules, are involved in gene expression at the post-transcriptional level. Hence, miRNAs contribute to gene regulation of various steps of different cell subsets' differentiation, maturation, and activation. The adaptive immune system arm, which exhibits the most specific immune responses, is also modulated by miRNAs. The generation and maturation of various T-cell subsets concomitant with B-cells is under precise regulation of miRNAs which function directly on the hallmark genes of each cell subset or indirectly through regulation of signaling pathway mediators and/or transcription factors involved in this maturation journey. In this review, we first discussed the origination process of common lymphocyte progenitors from hematopoietic stem cells, which further differentiate into various T-cell subsets under strict regulation of miRNAs and transcription factors. Subsequently, the differentiation of B-cells from common lymphocyte progenitors in bone marrow and periphery were discussed in association with a network of miRNAs and transcription factors.

Tetrahedral-Framework Nucleic Acid Loaded with MicroRNA-155 Enhances Immunocompetence in Cyclophosphamide-Induced Immunosuppressed Mice by Modulating Dendritic Cells and Macrophages

Nanomaterials are often used as immunomodulators because they can be tailored by a controllable process. In this work, a complex based on a tetrahedral framework nucleic acid delivery system and MicroRNA-155, known as T-155, is synthesized for the modulation of immunosuppression. In vivo, T-155 ameliorated spleen and thymus damage and hematopoiesis suppression in cyclophosphamide-induced immunosuppressed mice by promoting T-cell proliferation to resist oxidative stress. In vitro, T-155 induced immature dendritic cells (DCs) to differentiate into mature DCs by the ERK1/2 pathway and converted M0 macrophages (Mφ) into the M1 type by the NF-κB pathway to enhance the surveillance capabilities of antigen-presenting cells. The experimental results suggest that T-155 has therapeutic potential as an immunomodulator for immunosuppression.

Studies on the role of non-coding RNAs in controlling the activity of T cells in asthma

Bronchial asthma, commonly known as asthma, is a chronic inflammatory disease characterized by airway inflammation, increased responsiveness and changes in airway structure. T cells, particularly T helper cells, play a crucial role in the disease. Non-coding RNAs, which are RNAs that do not code for proteins, mainly include microRNAs, long non-coding RNAs, and circular RNAs, play a role in regulating various biological processes. Studies have shown that non-coding RNAs have an important role in the activation and transformation of T cells and other biological processes in asthma. The specific mechanisms and clinical applications are worth further examination. This article reviews the recent research on the role of microRNAs, long non-coding RNAs and circular RNAs in T cells in asthma.