Regulation and function of miRNA-21 in health and disease

Evaluation of Clinically Significant miRNAs Level by Machine Learning Approaches Utilizing Total Transcriptome Data

Analysis of the mechanisms underlying the occurrence and progression of cancer represents a key objective in contemporary clinical bioinformatics and molecular biology. Utilizing omics data, particularly transcriptomes, enables a detailed characterization of expression patterns and post-transcriptional regulation across various RNA types relative to the entire transcriptome. Here, we assembled a dataset comprising transcriptomic data from approximately 16 000 patients encompassing over 160 types of cancer. We employed state-of-the-art gradient boosting algorithms to discern intricate correlations in the expression levels of four clinically significant microRNAs, specifically, hsa-mir-21, hsa-let-7a-1, hsa-let-7b, and hsa-let-7i, with the expression levels of the remaining 60 660 unique RNAs. Our analysis revealed a dependence of the expression levels of the studied microRNAs on the concentrations of several small nucleolar RNAs and regulatory long noncoding RNAs. Notably, the roles of these RNAs in the development of specific cancer types had been previously established through experimental evidence. Subsequent evaluation of the created database will facilitate the identification of a broader spectrum of overarching dependencies related to changes in the expression levels of various RNA classes in diverse cancers. In future, it will make possible to discover unique alterations specific to certain types of malignant transformations.

Pharmacological and molecular mechanisms of miRNA-based therapies for targeting cardiovascular dysfunction

Advances in understanding gene expression regulation through epigenetic mechanisms have contributed to elucidating the regulatory mechanisms of noncoding RNAs as pharmacological targets in several diseases. MicroRNAs (miRs) are a class of evolutionarily conserved, short, noncoding RNAs regulating in a concerted manner gene expression at the post-transcriptional level by targeting specific sequences of the 3'-untranslated region of mRNA. Conversely, mechanisms of cardiovascular disease (CVD) remain largely elusive due to their life-course origins, multifactorial pathophysiology, and co-morbidities. In this regard, CVD treatment with conventional medications results in therapeutic failure due to progressive resistance to monotherapy, which overlooks the multiple factors involved, and reduced adherence to poly-pharmacology approaches. Consequently, considering its role in regulating complete gene pathways, miR-based drugs have appreciably progressed into preclinical and clinical testing. This review summarizes the current knowledge about the mechanisms of miRs in cardiovascular disease, focusing specifically on describing how clinical chemistry and physics have improved the stability of the miR molecule. In addition, a comprehensive review of the main miRs involved in cardiovascular disease and the clinical trials in which these molecules are used as active pharmacological molecules is provided.

Paediatrics congenital heart disease is associated with plasma miRNAs

BACKGROUND

Congenital heart disease (CHD) are the most common malformations from birth. The severity of the different forms of CHD varies extensively from superficial mild lesions with follow-up for decades without any treatment to complex cyanotic malformations requiring urgent surgical intervention. microRNAs have been found to be crucial in cardiac development, giving rise to possible phenotypes in CHD.

OBJECTIVES

We aimed to evaluate the expression of miRNAs in 86 children with CHD and divided into cyanotic and non-cyanotic heart defects and 110 controls.

METHODS

The miRNAs expression of miR-21-5p, miR-155-5p, miR-221-3p, miR-26a-5p, and miR-144-3p were analyzed by RT-qPCR. In addition, the expressions of the miRNAs studied were correlated with the clinical characteristics of both the children and the mothers.

RESULTS

The expression levels of miR-21-5-5p, miR-15-5p5, miR-221-3p, and miR-26-5p significantly differed between CHD and control subjects. Moreover, miR-21-5p levels were higher in patients with cyanotic versus non-cyanotic CHD patients.

CONCLUSION

The expression levels of miRNAs of pediatric patients with CHD could participating in the development of cardiac malformations. Additionally, the high expression of miR-21-5p in cyanotic CHD children may be related to greater severity of illness relative to non-cyanotic CHD.

IMPACT

This study adds to knowledge of the association between microRNAs and congenital heart disease in children. The expression levels of miR-21-5-5p, miR-15-5p5, miR-221-3p, and miR-26-5p of pediatric patients with CHD could be involved in the development and phenotype present in pediatric patients. miR-21-5p may help to discriminate between cyanotic and non-cyanotic CHD. In the future, the miRNAs studied could have applications as clinical biomarkers.

Detection of intracellular microRNA-21 for cancer diagnosis by a nanosystem containing a ZnO@polydopamine and DNAzyme probe

MicroRNAs (miRNAs) are a series of single-stranded non-coding ribonucleic acid (RNA) molecules which associated closely with various human diseases. Efficient strategies for detecting miRNAs are of great significance to cancer diagnosis and prognosis. Here we provide a novel nanosystem that can be applied for the detection of miRNAs. The nanosystem consists of a single-stranded deoxyribonucleic acid (DNA) probe and a probe carrier. The DNA probe was designed based on a deoxyribozyme (DNAzyme) with several necessary functional sequences and two fluorescent dyes labeled at proper sites. The ZnO@polydopamine (ZnO@PDA) nanomaterial serves not only as a probe carrier, but also as a supplier of Zn2+ that can activate the DNAzyme. The DNA probe will undergo a conformation alteration induced by miRNA-21, which then trigger the DNAzyme catalyzed self-cleavage reaction with the assist of Zn2+ provided by ZnO decomposition under weak acid environment. A change of fluorescent color will occur due to the interruption of fluorescence resonance energy transfer between the two fluorescent dyes, and the dissociated miRNA-21 can repeatedly induce the above responses to amplify the fluorescence signal. The feasibility of the whole procedure was demonstrated by various experiments. This nanosystem showed a good selectivity towards miRNA-21, and under the optimal incubation time of 2 hours, a good linear relationship was obtained in a concentration range of 0.01-2.0 nM with a detection limit of 3.8 pM. In in vivo detection, an obvious fluorescence color change from red to green can be observed in the presence of miRNA-21. The results proved that this miRNA detection strategy has a broad application prospect in tumor diagnosis and miRNA related biological studies.

Urinary Biomarkers for Lupus Nephritis: A Systems Biology Approach

Systemic lupus erythematosus (SLE) is the prototypical systemic autoimmune disorder. Kidney involvement, termed lupus nephritis (LN), is seen in 40-60% of patients with systemic lupus erythematosus (SLE). After the diagnosis, serial measurement of proteinuria is the most common method of monitoring treatment response and progression. However, present treatments for LN-corticosteroids and immunosuppressants-target inflammation, not proteinuria. Furthermore, subclinical renal inflammation can persist despite improving proteinuria. Serial kidney biopsies-the gold standard for disease monitoring-are also not feasible due to their inherent risk of complications. Biomarkers that reflect the underlying renal inflammatory process and better predict LN progression and treatment response are urgently needed. Urinary biomarkers are particularly relevant as they can be measured non-invasively and may better reflect the compartmentalized renal response in LN, unlike serum studies that are non-specific to the kidney. The past decade has overseen a boom in applying cutting-edge technologies to dissect the pathogenesis of diseases at the molecular and cellular levels. Using these technologies in LN is beginning to reveal novel disease biomarkers and therapeutic targets for LN, potentially improving patient outcomes if successfully translated to clinical practice.

The role of MicroRNAs in the diagnosis and treatment of oral premalignant disorders

Oral premalignant disorders (OPMDs) are a group of potentially malignant conditions that pose a significant health burden globally. MicroRNAs (miRNAs), small non-coding RNA molecules, have emerged as crucial regulators of gene expression and have been implicated in various biological processes, including carcinogenesis. This review synthesizes existing knowledge to provide a comprehensive understanding of the molecular mechanisms underlying OPMDs and to highlight the potential of miRNAs as promising biomarkers and therapeutic targets. Additionally, this review seeks to explore the potential of miRNA-based diagnostic biomarkers for early detection of OPMDs in the current literature on miRNAs in OPMDs, examining their involvement in disease pathogenesis, diagnostic potential, and therapeutic implications. Dysregulated miRNAs can target genes involved in critical cellular processes, such as cell cycle regulation, apoptosis, and DNA repair, leading to disease progression. Notably, miR-21, miR-31, miR-135b, and miR-486-5p have shown promise as potential biomarkers for early detection of oral premalignant lesions. Furthermore, the paper discusses the therapeutic implications of miRNAs in OPMDs. Preclinical studies have demonstrated the efficacy of miRNA-targeted therapies, such as miRNA mimics and inhibitors, in suppressing the growth of oral premalignant lesions. Early-phase clinical trials have shown promising results, indicating the potential for personalized treatment approaches. The findings underscore the importance of understanding the molecular mechanisms underlying these disorders and provide insights for the development of improved diagnostic and therapeutic strategies. However, they pose certain limitations given their intrinsic variability in expression profiles, the need for optimized isolation and detection methods, and potential hurdles in transitioning from preclinical success to clinical applications. Thus, future clinical studies are warranted to fully exploit the potential of miRNAs in the management of OPMDs.

From molecular pathogenesis to therapy: Unraveling non-coding RNAs/DNMT3A axis in human cancers

Cancer is a comprehensive classification encompassing more than 100 forms of malignancies that manifest in diverse tissues within the human body. Recent studies have provided evidence that aberrant epigenetic modifications are pivotal indicators of cancer. Epigenetics encapsulates DNA methyltransferases as a crucial class of modifiers. DNMTs, including DNMT3A, assume central roles in DNA methylation processes that orchestrate normal biological functions, such as gene transcription, predominantly in mammals. Typically, deviations in DNMT3A function engender distortions in factors that drive tumor growth and progression, thereby exacerbating the malignant phenotype of tumors. Consequently, such abnormalities pose significant challenges in cancer therapy because they impede treatment efficacy. Non-coding RNAs (ncRNAs) represent a group of RNA molecules that cannot encode functional proteins. Recent investigation attests to the crucial significance of regulatory ncRNAs in epigenetic regulation. Notably, recent reports have illuminated the complex interplay between ncRNA expression and epigenetic regulatory machinery, including DNMT3A, particularly in cancer. Recent findings have demonstrated that miRNAs, namely miR-770-5p, miR-101, and miR-145 exhibit the capability to target DNMT3A directly, and their aberration is implicated in diverse cellular abnormalities that predispose to cancer development. This review aims to articulate the interplay between DNMT3A and the ncRNAs, focusing on its impact on the development and progression of cancer, cancer therapy resistance, cancer stem cells, and prognosis. Importantly, the emergence of such reports that suggest a connection between DNMT3A and ncRNAs in several cancers indicates that this connecting axis offers a valuable target with significant therapeutic potential that might be exploited for cancer management.

miR-21 Expressed by Dermal Fibroblasts Enhances Skin Wound Healing Through the Regulation of Inflammatory Cytokine Expression

The management of skin wound healing is still a challenge. MicroRNA-21 (miR-21) has been reported to play important roles in wound repair; however, the underlying mechanism needs to be further clarified. The present study aimed to study the direct role of miR-21 in skin wound healing in miR-21 KO mice and to investigate the role of miR-21 in controlling the migration and proliferation of primary human skin cells and its underlying mechanism(s). miR-21 KO and wild-type (WT) mice were used for in vivo wound healing assays, while mouse and human primary skin cells were used for in vitro assays. miR-21 inhibitors or mimics or negative control small RNAs were transfected to either inhibit or enhance miR-21 expression in the human primary dermal fibroblasts or epidermal cells. RNA sequencing analysis was performed to identify the potential molecular pathways involved. We found that the loss of miR-21 resulted in slower wound healing in miR-21 KO mouse skin and especially delayed the healing of dermal tissue. In vitro assays demonstrated that the reduced expression of miR-21 caused by its inhibitor inhibited the migration of human primary dermal fibroblasts, which could be enhanced by increased miR-21 expression caused by miR-21 mimics. RNA-sequence analysis revealed that the inhibition of miR-21 expression downregulated the inflammatory response pathways associated with the decreased expression of inflammatory cytokines, and the addition of IL-1β into the culture medium enhanced the migration and proliferation of dermal fibroblasts in vitro. In conclusion, miR-21 in dermal fibroblasts can promote the migration and growth of epidermal and dermal cells to enhance skin wound healing through controlling the expression of inflammatory cytokines.

miRNAs and related genetic biomarkers according to the WHO glioma classification: From diagnosis to future therapeutic targets

In the 2021 WHO classification of Tumors of the Central Nervous System, additional molecular characteristics have been included, defining the following adult-type diffuse glioma entities: Astrocytoma IDH-mutant, Oligodendroglioma IDH-mutant and 1p/19q-codeleted, and Glioblastoma IDH-wildtype. Despite advances in genetic analysis, precision oncology, and targeted therapy, malignant adult-type diffuse gliomas remain "hard-to-treat tumors", indicating an urgent need for better diagnostic and therapeutic strategies. In the last decades, miRNA analysis has been a hotspot for researching and developing diagnostic, prognostic, and predictive biomarkers for various disorders, including brain cancer. Scientific interest has recently been directed towards therapeutic applications of miRNAs, with encouraging results. Databases such as NCBI, PubMed, and Medline were searched for a selection of articles reporting the relationship between deregulated miRNAs and genetic aberrations used in the latest WHO CNS classification. The current review discussed the recommended molecular biomarkers and genetic aberrations based on the 2021 WHO classification in adult-type diffuse gliomas, along with associated deregulated miRNAs. Additionally, the study highlights miRNA-based treatment advancements in adults with gliomas.

MicroRNAs as Plasma Biomarkers of Hepatocellular Carcinoma in Patients with Liver Cirrhosis-A Cross-Sectional Study

Ultrasound screening for hepatocellular carcinoma (HCC) in patients with liver cirrhosis has a poor sensitivity for small tumors. Circulating microRNAs (miRNAs) have been explored as HCC biomarkers, but results are diverging. Here, we evaluate if miRNAs up-regulated in HCC tissue can be detected in plasma and used as screening biomarkers for HCC. In this cross-sectional study, plasma, HCC tissue and surrounding non-tumorous liver tissue were collected from liver resections. Tissue miRNAs were identified and quantitated by RNA-sequencing analysis, and the fold-changes between HCC and surrounding liver tissue were calculated. The miRNAs up-regulated in HCCs were then re-analyzed in plasma from the same patients, and the miRNAs with the highest plasma levels were subsequently measured in plasma from an independent cohort of patients with cirrhosis or HCC. In tissues from 84 resected patients, RNA-sequencing detected 197 differentially expressed miRNAs, 40 of which had a raw count above 200 and were analyzed in plasma from the same cohort. Thirty-one miRNAs were selected for further analysis in 200 patients with HCC or cirrhosis. Of these, eleven miRNAs were significantly increased in HCC as compared to cirrhosis patients. Only miR-93-5p and miR-151a-3p were significantly associated with HCC, with an AUC of 0.662. In comparison, alpha-fetoprotein and des-gamma-carboxy prothrombin yielded an AUC of 0.816, which increased to 0.832 if miR-93-5p and miR-151a-3p were added. When including sex and age, the addition of miR-93-5p and miR-151a-3p did not further improve the AUC (from 0.910 to 0.911). In conclusion, micro-RNAs up-regulated in HCCs are detectable in plasma but have a poor performance as screening biomarkers of HCC.

MicroRNAs Associated with a Bad Prognosis in Acute Myeloid Leukemia and Their Impact on Macrophage Polarization

MicroRNAs (miRNAs) are short, non-coding ribonucleic acids (RNAs) associated with gene expression regulation. Since the discovery of the first miRNA in 1993, thousands of miRNAs have been studied and they have been associated not only with physiological processes, but also with various diseases such as cancer and inflammatory conditions. MiRNAs have proven to be not only significant biomarkers but also an interesting therapeutic target in various diseases, including cancer. In acute myeloid leukemia (AML), miRNAs have been regarded as a welcome addition to the limited therapeutic armamentarium, and there is a vast amount of data on miRNAs and their dysregulation. Macrophages are innate immune cells, present in various tissues involved in both tissue repair and phagocytosis. Based on their polarization, macrophages can be classified into two groups: M1 macrophages with pro-inflammatory functions and M2 macrophages with an anti-inflammatory action. In cancer, M2 macrophages are associated with tumor evasion, metastasis, and a poor outcome. Several miRNAs have been associated with a poor prognosis in AML and with either the M1 or M2 macrophage phenotype. In the present paper, we review miRNAs with a reported negative prognostic significance in cancer with a focus on AML and analyze their potential impact on macrophage polarization.

Detailed role of microRNA-mediated regulation of PI3K/AKT axis in human tumors

The regulation of signal transmission and biological processes, such as cell proliferation, apoptosis, metabolism, migration, and angiogenesis are greatly influenced by the PI3K/AKT signaling pathway. Highly conserved endogenous non-protein-coding RNAs known as microRNAs (miRNAs) have the ability to regulate gene expression by inhibiting mRNA translation or mRNA degradation. MiRNAs serve key role in PI3K/AKT pathway as upstream or downstream target, and aberrant activation of this pathway contributes to the development of cancers. A growing body of research shows that miRNAs can control the PI3K/AKT pathway to control the biological processes within cells. The expression of genes linked to cancers can be controlled by the miRNA/PI3K/AKT axis, which in turn controls the development of cancer. There is also a strong correlation between the expression of miRNAs linked to the PI3K/AKT pathway and numerous clinical traits. Moreover, PI3K/AKT pathway-associated miRNAs are potential biomarkers for cancer diagnosis, therapy, and prognostic evaluation. The role and clinical applications of the PI3K/AKT pathway and miRNA/PI3K/AKT axis in the emergence of cancers are reviewed in this article.

Tandem CRISPR nucleases-based lateral flow assay for amplification-free miRNA detection via the designed "locked RNA/DNA" as fuels

Currently, available biosensors based on CRISPR/Cas typically depend on coupling with nucleic acid amplification technologies to enhance their sensitivity. However, this approach often involves intricate amplification processes, which could be time-consuming and susceptible to contamination. In addition, signal readouts often require sophisticated and cumbersome equipment, obstructing the applicability of CRISPR/Cas assays in resource-limited regions. Herein, a tandem CRISPR/Cas13a/Cas12a mechanism (tanCRISPR) has been developed via the designed "Locked RNA/DNA" probe as fuels for the trans-cleavage nucleic acid of Cas13a and activated nucleic acid of Cas12a. Meanwhile, a lateral flow assay (LFA) is designed to combine with this tandem CRISPR/Cas13a/Cas12a mechanism (termed tanCRISPR-LFA), realizing the portable monitoring of miRNA-21. The tanCRISPR could realize the limit of detection at pM levels (266 folds lower than Cas13a-based miRNA testing alone) without the resort to target amplification procedures. Furthermore, the miRNA-21 levels of MDA-MB-231 cell extracts are sensed by tanCRISPR-LFA, which is comparable to qRT-PCR. With the virtues of portability, rapidity, sensitivity, and low cost, tanCRISPR-LFA is amenable for CRISPR/Cas-based biosensing and potential applications in the clinical diagnosis of miRNA-associated diseases.

Inhibitory effect of microRNA-21 on pathways and mechanisms involved in cardiac fibrosis development

Cardiac fibrosis is a pivotal cardiovascular disease (CVD) process and represents a notable health concern worldwide. While the complex mechanisms underlying CVD have been widely investigated, recent research has highlighted microRNA-21's (miR-21) role in cardiac fibrosis pathogenesis. In this narrative review, we explore the molecular interactions, focusing on the role of miR-21 in contributing to cardiac fibrosis. Various signaling pathways, such as the RAAS, TGF-β, IL-6, IL-1, ERK, PI3K-Akt, and PTEN pathways, besides dysregulation in fibroblast activity, matrix metalloproteinases (MMPs), and tissue inhibitors of MMPs cause cardiac fibrosis. Besides, miR-21 in growth factor secretion, apoptosis, and endothelial-to-mesenchymal transition play crucial roles. miR-21 capacity regulatory function presents promising insights for cardiac fibrosis. Moreover, this review discusses numerous approaches to control miR-21 expression, including antisense oligonucleotides, anti-miR-21 compounds, and Notch signaling modulation, all novel methods of cardiac fibrosis inhibition. In summary, this narrative review aims to assess the molecular mechanisms of cardiac fibrosis and its essential miR-21 function.

Differential gene expression of cytokines, receptors, and miRNAs in individuals living with HIV-1 and vaccinated against yellow fever

Between 2016 and 2018, Brazil faced a yellow fever (YF) outbreak, which led to an expansion of vaccination coverage. The coexistence of the YF outbreak and the HIV-1 epidemic in Brazil raised concerns regarding the immune response and vaccine effectiveness in individuals living with HIV (PLWH). The aim of this study was to investigate the immune response to YF vaccination in PLWH and HIV-uninfected individuals as controls. Transcript levels of immunomodulatory molecules, including IL-6, IL-10, IL-21, TGF-β, CD19, CD163, miR-21, miR-146, and miR-155, were measured using RTqPCR. TCD4+ cells were evaluated by cytometry, and neutralizing antibody (Nab) titers were detected by a micro plaque-reduction neutralization test. The findings of our study revealed several noteworthy observations. First, there was a notable reduction in the circulation of TCD4+ cells postvaccination. Among people living with HIV (PLWH), we observed an increase in the expression of IL-10 following vaccination, while IL-6 expression was diminished in PLWH with lower TCD4+ counts. Furthermore, we identified the downregulation of CD19 and TGF-β, along with the upregulation of IL-21 and CD163. Notably, we observed positive correlations between the levels of IL-10/IL-21, IL-10/CD163, and IL-6/CD19. Additionally, there was a positive correlation between miRNAs 146 and 155. It is important to emphasize that all participants exhibited robust neutralizing antibody responses after receiving 17DD YF vaccination. In this context, the gene expression data presented can be useful for biomarker studies of protective antibodies induced by YF vaccination. This study sheds light on immune mechanisms in individuals living with HIV and YF vaccination.

An Overview of Supramolecular Platforms Boosting Drug Delivery

Numerous supramolecular platforms inspired by natural self-assembly are exploited as drug delivery systems. The spontaneous arrangement of single building blocks into inorganic and organic structures is determined and controlled by noncovalent forces such as electrostatic interactions, π-π interactions, hydrogen bonds, and van der Waals interactions. This review describes the main structures and characteristics of several building blocks used to obtain stable, self-assembling nanostructures tailored for numerous biological applications. Owing to their versatility, biocompatibility, and controllability, these nanostructures find application in diverse fields ranging from drug/gene delivery, theranostics, tissue engineering, and nanoelectronics. Herein, we described the different approaches used to design and functionalize these nanomaterials to obtain selective drug delivery in a specific disease. In particular, the review highlights the efficiency of these supramolecular structures in applications related to infectious diseases and cancer.

Non-Coding RNAs as Potential Targets for Diagnosis and Treatment of Oral Lichen Planus: A Narrative Review

Oral lichen planus (OLP) is a chronic inflammatory disease that is characterized by the infiltration of T cells into the oral mucosa, causing the apoptosis of basal keratinocytes. OLP is a multifactorial disease of unknown etiology and is not solely caused by the malfunction of a single key gene but rather by various intracellular and extracellular factors. Non-coding RNAs play a critical role in immunological homeostasis and inflammatory response and are found in all cell types and bodily fluids, and their expression is closely regulated to preserve normal physiologies. The dysregulation of non-coding RNAs may be highly implicated in the onset and progression of diverse inflammatory disorders, including OLP. This narrative review summarizes the role of non-coding RNAs in molecular and cellular changes in the oral epithelium during OLP pathogenesis.

Exosomal microRNA/miRNA Dysregulation in Respiratory Diseases: From Mycoplasma-Induced Respiratory Disease to COVID-19 and Beyond

Respiratory diseases represent a significant economic and health burden worldwide, affecting millions of individuals each year in both human and animal populations. MicroRNAs (miRNAs) play crucial roles in gene expression regulation and are involved in various physiological and pathological processes. Exosomal miRNAs and cellular miRNAs have been identified as key regulators of several immune respiratory diseases, such as chronic respiratory diseases (CRD) caused by Mycoplasma gallisepticum (MG), Mycoplasma pneumoniae pneumonia (MMP) caused by the bacterium Mycoplasma pneumoniae, coronavirus disease 2019 (COVID-19), chronic obstructive pulmonary disease (COPD), asthma, and acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Consequently, miRNAs seem to have the potential to serve as diagnostic biomarkers and therapeutic targets in respiratory diseases. In this review, we summarize the current understanding of the functional roles of miRNAs in the above several respiratory diseases and discuss the potential use of miRNAs as stable diagnostic biomarkers and therapeutic targets for several immune respiratory diseases, focusing on the identification of differentially expressed miRNAs and their targeting of various signaling pathways implicated in disease pathogenesis. Despite the progress made, unanswered questions and future research directions are discussed to facilitate personalized and targeted therapies for patients with these debilitating conditions.

Noncoding RNAs as regulators of STAT3 pathway in gastrointestinal cancers: Roles in cancer progression and therapeutic response

Gastrointestinal (GI) tumors (cancers of the esophagus, gastric, liver, pancreas, colon, and rectum) contribute to a large number of deaths worldwide. STAT3 is an oncogenic transcription factor that promotes the transcription of genes associated with proliferation, antiapoptosis, survival, and metastasis. STAT3 is overactivated in many human malignancies including GI tumors which accelerates tumor progression, metastasis, and drug resistance. Research in recent years demonstrated that noncoding RNAs (ncRNAs) play a major role in the regulation of many signaling pathways including the STAT3 pathway. The major types of endogenous ncRNAs that are being extensively studied in oncology are microRNAs, long noncoding RNAs, and circular RNAs. These ncRNAs can either be tumor-promoters or tumor-suppressors and each one of them imparts their activity via different mechanisms. The STAT3 pathway is also tightly modulated by ncRNAs. In this article, we have elaborated on the tumor-promoting role of STAT3 signaling in GI tumors. Subsequently, we have comprehensively discussed the oncogenic as well as tumor suppressor functions and mechanism of action of ncRNAs that are known to modulate STAT3 signaling in GI cancers.

Stabilizing the neural barrier - A novel approach in pain therapy

Chronic and neuropathic pain are a widespread burden. Incomplete understanding of underlying pathomechanisms is one crucial factor for insufficient treatment. Recently, impairment of the blood nerve barrier (BNB) has emerged as one key aspect of pain initiation and maintenance. In this narrative review, we discuss several mechanisms and putative targets for novel treatment strategies. Cells such as pericytes, local mediators like netrin-1 and specialized proresolving mediators (SPMs), will be covered as well as circulating factors including the hormones cortisol and oestrogen and microRNAs. They are crucial in either the BNB or similar barriers and associated with pain. While clinical studies are still scarce, these findings might provide valuable insight into mechanisms and nurture development of therapeutic approaches.

Exploring the Feasibility of Circulating miRNAs as Diagnostic and Prognostic Biomarkers in Osteoarthritis: Challenges and Opportunities

Osteoarthritis (OA) is a prevalent degenerative joint disease characterized by progressive cartilage degradation and joint inflammation. As the most common aging-related joint disease, OA is marked by inadequate extracellular matrix synthesis and the breakdown of articular cartilage. However, traditional diagnostic methods for OA, relying on clinical assessments and radiographic imaging, often need to catch up in detecting early-stage disease or i accurately predicting its progression. Consequently, there is a growing interest in identifying reliable biomarkers that can facilitate early diagnosis and prognosis of OA. MicroRNAs (miRNAs) have emerged as potential candidates due to their involvement in various cellular processes, including cartilage homeostasis and inflammation. This review explores the feasibility of circulating miRNAs as diagnostic and prognostic biomarkers in OA, focusing on knee OA while shedding light on the challenges and opportunities associated with their implementation in clinical practice.

Characterization of the skin keloid microenvironment

Keloids are a fibroproliferative skin disorder that develops in people of all ages. Keloids exhibit some cancer-like behaviors, with similar genetic and epigenetic modifications in the keloid microenvironment. The keloid microenvironment is composed of keratinocytes, fibroblasts, myofibroblasts, vascular endothelial cells, immune cells, stem cells and collagen fibers. Recent advances in the study of keloids have led to novel insights into cellular communication among components of the keloid microenvironment as well as potential therapeutic targets for treating keloids. In this review, we summarized the nature of genetic and epigenetic regulation in keloid-derived fibroblasts, epithelial-to-mesenchymal transition of keratinocytes, immune cell infiltration into keloids, the differentiation of keloid-derived stem cells, endothelial-to-mesenchymal transition of vascular endothelial cells, extracellular matrix synthesis and remodeling, and uncontrolled angiogenesis in keloids with the aim of identifying new targets for therapeutic benefit. Video Abstract.

MicroRNAs in aldosterone production and action

Aldosterone is a cardiovascular hormone with a key role in blood pressure regulation, among other processes, mediated through its targeting of the mineralocorticoid receptor in the renal tubule and selected other tissues. Its secretion from the adrenal gland is a highly controlled process subject to regulatory influence from the renin-angiotensin system and the hypothalamic-pituitary-adrenal axis. MicroRNAs are small endogenous non-coding RNA molecules capable of regulating gene expression post-transcriptionally through stimulation of mRNA degradation or suppression of translation. Several studies have now identified that microRNA levels are changed in cases of aldosterone dysregulation and that microRNAs are capable of regulating the expression of various genes involved in aldosterone production and action. In this article we summarise the major studies concerning this topic. We also discuss the potential role for circulating microRNAs as diagnostic biomarkers for primary aldosteronism, a highly treatable form of secondary hypertension, which would be highly desirable given the current underdiagnosis of this condition.

Emerging roles of noncoding RNAs in human cancers

Studies have found that RNA encoding proteins only account for a small part of the total number, most RNA is non-coding RNA, and non-coding RNA may affect the occurrence and development of human cancers by affecting gene expression, therefore play an important role in human pathology. At present, ncRNAs studied include miRNA, circRNA, lncRNA, piRNA, and snoRNA, etc. After decades of research, the basic role of these ncRNAs in many cancers has been clear. As far as we know, the role of miRNAs in cancer is one of the hottest research directions, however, it is also found that the imbalance of ncRNAs will affect the occurrence of gastric cancer, breast cancer, lung cancer, meanwhile, it may also affect the prognosis of these cancers. Therefore, the study of ncRNAs in cancers may help to find new cancer diagnostic and treatment methods. Here, we reviewed the biosynthesis and characteristics of miRNA, cricRNA, and lncRNA etc., their roles in human cancers, as well as the mechanism through which these ncRNAs affect human cancers.

The Role and Mechanism of MicroRNA 21 in Osteogenesis: An Update

MicroRNAs are short, single-stranded ribonucleic acids expressed endogenously in the body to regulate gene expression at the post-translational level, with exogenous microRNA offering an attractive approach to therapy. Among the myriad microRNA candidates involved in controlling bone homeostasis and remodeling, microRNA 21 (miR21) is the most abundant. This paper discusses the studies conducted on the role and mechanism of human miR21 (hsa-miR21) in the regulation of bones and the various pathways mediated by miR21, and explores the feasibility of employing exogenous miR21 as a strategy for promoting osteogenesis. From the literature review, it was clear that miR21 plays a dual role in bone metabolism by regulating both bone formation and bone resorption. There is substantial evidence to date from both in vitro and in vivo studies that exogenous miR21 can successfully accelerate new bone synthesis in the context of bone loss due to injury or osteoporosis. This supports the exploration of applications of exogenous miR21 in bone regenerative therapy in the future.

High Expression Levels of miR-21-5p in Younger Hospitalized COVID-19 Patients Are Associated with Mortality and Critical Disease

In COVID-19, critical disease and invasive mechanical ventilation (IMV) increase the risk of death, mainly in patients over 60 years of age.

OBJECTIVES

To find the relationship between miR-21-5p and miR-146a-5p in terms of the severity, IMV, and mortality in hospitalized COVID-19 patients younger than 55 years of age.

METHODS

The patients were stratified according to disease severity using the IDSA/WHO criteria for severe and critical COVID-19 and subclassified into critical non-survivors and critical survivors.

RESULTS

Ninety-seven severe/critical COVID-19 patients were included; 81.3% of the deceased were male and 18.8% were female. Higher expression miR-21-5p levels were associated as follows: severe vs. critical disease (p = 0.007, FC = 0.498), PaO₂/FiO₂ index, mild vs. severe (p = 0.027, FC = 0.558), and survivors vs. non-survivors (p = 0.03, FC = 0.463). Moreover, we identified correlations with clinical variables: CRP (rho = -0.54, p < 0.001), D-dimer (rho = -0.47, p < 0.05), related to damage in the kidney (rho = 0.60, p < 0.001), liver (rho = 0.41, p < 0.05), and lung (rho = 0.54, p < 0.001). Finally, miR-21-5p thresholds were calculated according to severity (8.191), IMV (8.191), and mortality (8.237); these values increased the risk of developing a critical disease (OR = 4.19), the need for IMV (OR = 5.63), and death (OR = 6.00).

CONCLUSION

Increased expression levels of miR-21-5p are related to worse outcome of COVID-19 in younger hospitalized patients.

The deleted in oral cancer (DOC1 aka CDK2AP1) tumor suppressor gene is downregulated in oral squamous cell carcinoma by multiple microRNAs

Cyclin-dependent kinase 2-associated protein 1 (CDK2AP1; also known as deleted in oral cancer or DOC1) is a tumor suppressor gene known to play functional roles in both cell cycle regulation and in the epigenetic control of embryonic stem cell differentiation, the latter as a core subunit of the nucleosome remodeling and histone deacetylation (NuRD) complex. In the vast majority of oral squamous cell carcinomas (OSCC), expression of the CDK2AP1 protein is reduced or lost. Notwithstanding the latter (and the DOC1 acronym), mutations or deletions in its coding sequence are extremely rare. Accordingly, CDK2AP1 protein-deficient oral cancer cell lines express as much CDK2AP1 mRNA as proficient cell lines. Here, by combining in silico and in vitro approaches, and by taking advantage of patient-derived data and tumor material in the analysis of loss of CDK2AP1 expression, we identified a set of microRNAs, namely miR-21-5p, miR-23b-3p, miR-26b-5p, miR-93-5p, and miR-155-5p, which inhibit its translation in both cell lines and patient-derived OSCCs. Of note, no synergistic effects were observed of the different miRs on the CDK2AP1-3-UTR common target. We also developed a novel approach to the combined ISH/IF tissue microarray analysis to study the expression patterns of miRs and their target genes in the context of tumor architecture. Last, we show that CDK2AP1 loss, as the result of miRNA expression, correlates with overall survival, thus highlighting the clinical relevance of these processes for carcinomas of the oral cavity.

miR-21-5p prevents doxorubicin-induced cardiomyopathy by downregulating BTG2

Cardiomyocyte apoptosis has been characterized as one of the major mechanisms underlying doxorubicin (DOX)-induced cardiomyopathy. MicroRNA-21-5p (miR-21-5p) was reported to mitigate ischemia-induced cardiomyocyte apoptosis and cardiac injury. However, to our knowledge, the functional role of miR-21-5p in DOX-induced cardiomyopathy is unclear. In this study, we explored the role of miR-21-5p in DOX-induced cardiac injury. The expression level of miR-21-5p was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Dual luciferase reporter assay was used to verify the potential target gene of miR-21-5p. The apoptosis rate of NRCMs was detected by TUNEL staining assay. Western blot analysis was used to detect the protein expression levels of Bax, Bcl-2, Caspase3, cleaved-Caspase3 and BTG2. For animal studies, mice were injected with AAV9-miR-21-5p or AAV9-Empty viruses, and treated with DOX at a dose of 5 mg/kg per week through intraperitoneally administration. After 4 weeks of DOX treatment, mice were subjected to echocardiography to measure the left ventricular ejection fraction (EF) and fractional shortening (FS). Results showed that miR-21-5p was upregulated in both DOX-treated primary cardiomyocytes and mouse heart tissues. Interestingly, enhanced miR-21-5p expression inhibited DOX-induced cardiomyocyte apoptosis and oxidative stress, while decreased miR-21-5p expression promoted cardiomyocyte apoptosis and oxidative stress. Furthermore, cardiac overexpression of miR-21-5p protected against DOX-induced cardiac injury. The mechanistic study indicated that BTG2 was a target gene of miR-21-5p. The anti-apoptotic effect of miR-21-5p could be inhibited by BTG2 overexpression. Conversely, inhibition of BTG2 rescued the pro-apoptotic effect of miR-21-5p inhibitor. Taken together, our study showed that miR-21-5p could prevent DOX-induced cardiomyopathy by downregulating BTG2.

Experimental Validation and Prediction of Super-Enhancers: Advances and Challenges

Super-enhancers (SEs) are cis-regulatory elements of the human genome that have been widely discussed since the discovery and origin of the term. Super-enhancers have been shown to be strongly associated with the expression of genes crucial for cell differentiation, cell stability maintenance, and tumorigenesis. Our goal was to systematize research studies dedicated to the investigation of structure and functions of super-enhancers as well as to define further perspectives of the field in various applications, such as drug development and clinical use. We overviewed the fundamental studies which provided experimental data on various pathologies and their associations with particular super-enhancers. The analysis of mainstream approaches for SE search and prediction allowed us to accumulate existing data and propose directions for further algorithmic improvements of SEs' reliability levels and efficiency. Thus, here we provide the description of the most robust algorithms such as ROSE, imPROSE, and DEEPSEN and suggest their further use for various research and development tasks. The most promising research direction, which is based on topic and number of published studies, are cancer-associated super-enhancers and prospective SE-targeted therapy strategies, most of which are discussed in this review.

Liquid Biopsies Poorly miRror Renal Ischemia-Reperfusion Injury

Acute kidney injury (AKI) is the rapid reduction in renal function. It is often difficult to detect at an early stage. Biofluid microRNAs (miRs) have been proposed as novel biomarkers due to their regulatory role in renal pathophysiology. The goal of this study was to determine the overlap in AKI miRNA profiles in the renal cortex, urine, and plasma samples collected from a rat model of ischemia-reperfusion (IR)-induced AKI. Bilateral renal ischemia was induced by clamping the renal pedicles for 30 min, followed by reperfusion. Urine was then collected over 24 h, followed by terminal blood and tissue collection for small RNA profiling. Differentially expressed (IR vs. sham) miRs within the urine and renal cortex sample types demonstrated a strong correlation in normalized abundance regardless of injury (IR and sham: R2 = 0.8710 and 0.9716, respectively). Relatively few miRs were differentially expressed in multiple samples. Further, there were no differentially expressed miRs with clinically relevant sequence conservation common between renal cortex and urine samples. This project highlights the need for a comprehensive analysis of potential miR biomarkers, including analysis of pathological tissues and biofluids, with the goal of identifying the cellular origin of altered miRs. Analysis at earlier timepoints is needed to further evaluate clinical potential.

Is miR-21 A Therapeutic Target in Cardiovascular Disease?

microRNA-21 (miR-21) serves a multitude of functions at the molecular level through its regulation of messenger RNA. Previous research has sparked interest in the role of miR-21 as a potential therapeutic target in cardiovascular diseases. miR-21 expression contributes to the differentiation, proliferation, and maturation of many cell types, such as fibroblasts, endothelial cells, cardiomyocytes, and endothelial progenitor cells. The function of miR-21 depends upon its expression level in the specific cell types and downstream targets, which determine cell fate. Under pathological conditions, the expression level of miR-21 is altered, leading to abnormal gene regulation of downstream signaling and cardiovascular diseases such as hypertension, cardiac hypertrophy and fibrosis, atherosclerosis, and heart failure. Agomirs or antagomirs can be introduced into the respective tissue type to reverse or stop the progression of the disease. Exosomes in the extracellular vesicles, which mediate many cellular events with high biocompatibility, have a high potential of efficiently delivering miR-21 to their targeted cells. The critical role of miR-21 in cardiovascular disease (CVD) is indisputable, but there are controversial reports on the function of miR-21 in the same disease. This discrepancy sparks interest in better understanding the role of miR-21 in different tissues under different stages of various diseases and the mechanism of how miR-21 inhibitors work.

Potential Pathogenic Impact of Cow’s Milk Consumption and Bovine Milk-Derived Exosomal MicroRNAs in Diffuse Large B-Cell Lymphoma

Epidemiological evidence supports an association between cow’s milk consumption and the risk of diffuse large B-cell lymphoma (DLBCL), the most common non-Hodgkin lymphoma worldwide. This narrative review intends to elucidate the potential impact of milk-related agents, predominantly milk-derived exosomes (MDEs) and their microRNAs (miRs) in lymphomagenesis. Upregulation of PI3K-AKT-mTORC1 signaling is a common feature of DLBCL. Increased expression of B cell lymphoma 6 (BCL6) and suppression of B lymphocyte-induced maturation protein 1 (BLIMP1)/PR domain-containing protein 1 (PRDM1) are crucial pathological deviations in DLBCL. Translational evidence indicates that during the breastfeeding period, human MDE miRs support B cell proliferation via epigenetic upregulation of BCL6 (via miR-148a-3p-mediated suppression of DNA methyltransferase 1 (DNMT1) and miR-155-5p/miR-29b-5p-mediated suppression of activation-induced cytidine deaminase (AICDA) and suppression of BLIMP1 (via MDE let-7-5p/miR-125b-5p-targeting of PRDM1). After weaning with the physiological termination of MDE miR signaling, the infant’s BCL6 expression and B cell proliferation declines, whereas BLIMP1-mediated B cell maturation for adequate own antibody production rises. Because human and bovine MDE miRs share identical nucleotide sequences, the consumption of pasteurized cow’s milk in adults with the continued transfer of bioactive bovine MDE miRs may de-differentiate B cells back to the neonatal “proliferation-dominated” B cell phenotype maintaining an increased BLC6/BLIMP1 ratio. Persistent milk-induced epigenetic dysregulation of BCL6 and BLIMP1 expression may thus represent a novel driving mechanism in B cell lymphomagenesis. Bovine MDEs and their miR cargo have to be considered potential pathogens that should be removed from the human food chain.

An overview of the current advances in the treatment of inflammatory diseases using mesenchymal stromal cell secretome

The growing interest in mesenchymal stromal cell (MSC) therapy has been leading to the utilization of its therapeutic properties in a variety of inflammatory diseases. The clinical translation of the related research from bench to bedside is cumbersome due to some obvious limitations of cell therapy. It is evident from the literature that the MSC secretome components mediate their wide range of functions. Cell-free therapy using MSC secretome is being considered as an emerging and promising area of biotherapeutics. The secretome mainly consists of bioactive factors, free nucleic acids, and extracellular vesicles. Constituents of the secretome are greatly influenced by the cell's microenvironment. The broad array of immunomodulatory properties of MSCs are now being employed to target inflammatory diseases. This review focuses on the emerging MSC secretome therapies for various inflammatory diseases. The mechanism of action of the various anti-inflammatory factors is discussed. The potential of MSC secretome as a viable anti-inflammatory therapy is deliberated.

Epigenetic reprogramming in cancer: From diagnosis to treatment

Disruption of the epigenetic program of gene expression is a hallmark of cancer that initiates and propagates tumorigenesis. Altered DNA methylation, histone modifications and ncRNAs expression are a feature of cancer cells. The dynamic epigenetic changes during oncogenic transformation are related to tumor heterogeneity, unlimited self-renewal and multi-lineage differentiation. This stem cell-like state or the aberrant reprogramming of cancer stem cells is the major challenge in treatment and drug resistance. Given the reversible nature of epigenetic modifications, the ability to restore the cancer epigenome through the inhibition of the epigenetic modifiers is a promising therapy for cancer treatment, either as a monotherapy or in combination with other anticancer therapies, including immunotherapies. Herein, we highlighted the main epigenetic alterations, their potential as a biomarker for early diagnosis and the epigenetic therapies approved for cancer treatment.

Outside the limit: questioning the distance restrictions for cooperative miRNA binding sites

Among the concepts in biology that are widely taken granted is a potentiated cooperative effect of multiple miRNAs on the same target. This strong hypothesis contrasts insufficient experimental evidence. The quantity as well as the quality of required side constraints of cooperative binding remain largely hidden. For miR-21-5p and miR-155-5p, two commonly investigated regulators across diseases, we selected 15 joint target genes. These were chosen to represent various neighboring 3'UTR binding site constellations, partially exceeding the distance rules that have been established for over a decade. We identified different cooperative scenarios with the binding of one miRNA enhancing the binding effects of the other miRNA and vice versa. Using both, reporter assays and whole proteome analyses, we observed these cooperative miRNA effects for genes that bear 3'UTR binding sites at distances greater than the previously defined limits. Astonishingly, the experiments provide even stronger evidence for cooperative miRNA effects than originally postulated. In the light of these findings the definition of targetomes specified for single miRNAs need to be refined by a concept that acknowledges the cooperative effects of miRNAs.

Lactobacillus casei condition medium downregulates miR-21 relative expression in HT-29 colorectal cancer cell line

Previous research has demonstrated promising outcomes regarding the advantageous impact of probiotics in both cancer prevention and treatment. Nevertheless, the precise molecular mechanisms underpinning these effects remain elusive. Recent investigations have proposed a potential involvement of micro ribonucleic acids (miRNAs) in mediating the favorable influence of probiotics on cancerous cells. This study was designed to evaluate the effect of Lactobacillus casei condition medium on miR-21 relative expression in HT-29 colorectal cancer cells. Lactobacillus casei condition medium mixed with RPMI in different proportions (1:1, 1:3, and 1:7) and utilized to treat HT-29 cells for 24 and 48 h. Subsequently, percentage of early and late apoptotic cells were identified using a flow cytometry instrument. A real-time polymerase chain reaction was carried out to determine the relative expression of miR-21. Our findings revealed that L. casei condition medium induces apoptosis in a time- and dose-dependent manner in HT-29 cells. Furthermore, we found a significantly downregulated miR-21 after treatment with high doses of L. casei condition medium after 48 h. Overall, our results provide valuable insights into a potential mechanism through which L. casei condition medium mediates its apoptotic effect in colorectal cancer cells through downregulation of miR-21. However, further investigations are required to unravel its therapeutic, diagnostic, and treatment monitoring potential.

2'-N-Alkylaminocarbonyl-2'-amino-LNA: Synthesis, duplex stability, nuclease resistance, and in vitro anti-microRNA activity

2'-Amino-LNA has the potential to acquire various functions through chemical modification at the 2'-nitrogen atom. This study focused on 2'-N-alkylaminocarbonyl 2'-amino-LNA, which is a derivative of 2'-amino-LNA. We evaluated its practical usefulness as a chemical modification of anti-miRNA oligonucleotide. The synthesis of phosphoramidites of 2'-N-alkylaminocarbonyl substituted 2'-amino-LNA bearing thymine and 5-methylcytosine proceeded in good yields. Incorporating the 2'-N-alkylaminocarbonyl-2'-amino-LNA monomers into oligonucleotides improved the duplex stability for complementary RNA strands and robust nuclease resistance. Moreover, 2'-N-alkylaminocarbonyl-2'-amino-LNA is a promising scaffold that significantly increases the potency of anti-miRNA oligonucleotides.

The Importance of Using Exosome-Loaded miRNA for the Treatment of Spinal Cord Injury

Spinal cord injury (SCI) is a major traumatic disease of the central nervous system characterized by high rates of disability and mortality. Many studies have shown that SCI can be divided into the two stages of primary and secondary injury. Primary injury leads to pathophysiological changes, while consequential injury is even more fatal, including a series of harmful reactions that expand the scope and degree of SCI. Because the pathological process of SCI is highly complex, there is still no clear and effective clinical treatment strategy. Exosomes, membrane-bound extracellular vesicles (EVs) with a diameter of 30-200 nm, have emerged as an ideal vector to deliver therapeutic molecules. At the same time, increasing numbers of studies have shown that miRNAs play a momentous role in the process of SCI. In recent studies, researchers have adopted exosomes as carriers of miRNAs with potential therapeutic effects in SCI. In this review, we summarize relevant articles describing exosomes as miRNA carriers for SCI, after which we discuss further implications and perspectives of this novel treatment modality.

MicroRNAs in T Cell-Immunotherapy

MicroRNAs (miRNAs) act as master regulators of gene expression in homeostasis and disease. Despite the rapidly growing body of evidence on the theranostic potential of restoring miRNA levels in pre-clinical models, the translation into clinics remains limited. Here, we review the current knowledge of miRNAs as T-cell targeting immunotherapeutic tools, and we offer an overview of the recent advances in miRNA delivery strategies, clinical trials and future perspectives in RNA interference technologies.

Role of miRNA in Melanoma Development and Progression

Melanoma is one of the most aggressive and progressive skin cancers. It develops from normal pigment-producing cells known as melanocytes, so it is important to know the mechanism behind such transformations. The study of metastasis mechanisms is crucial for a better understanding the biology of neoplastic cells. Metastasis of melanoma, or any type of cancer, is a multi-stage process in which the neoplastic cells leave the primary tumour, travel through the blood and/or lymphatic vessels, settle in distant organs and create secondary tumours. MicroRNA (miRNA) can participate in several steps of the metastatic process. This review presents the role of miRNA molecules in the development and progression as well as the immune response to melanoma.

Deciphering the Antifibrotic Property of Metformin

Fibrosis is a chronic progressive and incurable disease leading to organ dysfunction. It is characterized by the accumulation of extracellular matrix proteins produced by mesenchymal stem cells (MSCs) differentiating into myofibroblasts. Given the complexity of its pathophysiology, the search for effective treatments for fibrosis is of paramount importance. Metformin, a structural dimethyl analog of the galegine guanide extracted from the "French Lilac" (Fabaceae Galega officinalis), is the most widely used antidiabetic drug, recently recognized for its antifibrotic effects through ill-characterized mechanisms. The in vitro model of TGF-β1-induced fibrosis in human primary pulmonary mesenchymal stem cells (HPMSCs), identified as CD248+ and CD90+ cells, was used to study the effects of metformin extracts. These effects were tested on the expression of canonical MSC differentiation markers, immune/inflammatory factors and antioxidative stress molecules using qRT-PCR (mRNA, miRNA), immunofluorescence and ELISA experiments. Interestingly, metformin is able to reduce/modulate the expression of different actors involved in fibrosis. Indeed, TGF-β1 effects were markedly attenuated by metformin, as evidenced by reduced expression of three collagen types and Acta2 mRNAs. Furthermore, metformin attenuated the effects of TGF-β1 on the expression of PDGF, VEGF, erythropoietin, calcitonin and profibrotic miRs, possibly by controlling the expression of several key TGF/Smad factors. The expression of four major fibrogenic MMPs was also reduced by metformin treatment. In addition, metformin controlled MSC differentiation into lipofibroblasts and osteoblasts and had the ability to restore redox balance via the Nox4/Nrf2, AMP and Pi3K pathways. Overall, these results show that metformin is a candidate molecule for antifibrotic effect and/or aiming to combat the development of chronic inflammatory diseases worldwide.

Parallel synthesis of oligonucleotides containing N-acyl amino-LNA and their therapeutic effects as anti-microRNAs

2'-Amino-locked nucleic acid (ALNA), maintains excellent duplex stability, and the nitrogen at the 2'-position is an attractive scaffold for functionalization. Herein, a facile and efficient method for the synthesis of various 2'-N-acyl amino-LNA derivatives by direct acylation of the 2'-amino moiety contained in the synthesized oligonucleotides and its fundamental properties are described. The introduction of the acylated amino-LNA enhances the potency of the molecules as therapeutic anti-microRNA oligonucleotides.

The Versatile Role of miR-21 in Renal Homeostasis and Diseases

MicroRNAs (miRNAs) are small, non-coding RNA species that control gene expression and confer robustness to biological processes. Over the last two decades, their important roles during kidney development, homeostasis and the treatment of diseases have been established, in particular during the onset and progression of various forms of acute and chronic renal disorders. In recent years, miR-21, one of the best-characterized miRNAs to date, has received much attention in renal physiology in particular given its high degree of conservation and expression in kidneys, as well as its potent pathogenic role in various debilitating renal diseases. This review summarizes the current knowledge on miR-21’s involvement in both renal homeostasis and diseases, in particular its double-edged-sword role in acute versus chronic kidney injuries. Finally, we also discuss the potential of miR-21 as a biomarker and therapeutic target in renal diseases.

Cellular microRNAs correlate with clinical parameters in multiple injury patients

INTRODUCTION

The pathophysiology of the inflammatory response after major trauma is complex, and the magnitude correlates with severity of tissue injury and outcomes. Study of infection-mediated immune pathways has demonstrated that cellular microRNAs may modulate the inflammatory response. The authors hypothesize that the expression of microRNAs would correlate to complicated recoveries in polytrauma patients (PtPs).

METHODS

Polytrauma patients enrolled in the prospective observational Tissue and Data Acquisition Protocol with Injury Severity Score of >15 were selected for this study. Polytrauma patients were divided into complicated recoveries and uncomplicated recovery groups. Polytrauma patients' blood samples were obtained at the time of admission (T0). Established biomarkers of systemic inflammation, including cytokines and chemokines, were measured using multiplexed Luminex-based methods, and novel microRNAs were measured in plasma samples using multiplex RNA hybridization.

RESULTS

Polytrauma patients (n = 180) had high Injury Severity Score (26 [20-34]) and complicated recovery rate of 33%. MicroRNAs were lower in PtPs at T0 compared with healthy controls, and bivariate analysis demonstrated that variations of microRNAs correlated with age, race, comorbidities, venous thromboembolism, pulmonary complications, complicated recovery, and mortality. Positive correlations were noted between microRNAs and interleukin 10, vascular endothelial growth factor, Acute Physiology and Chronic Health Evaluation, and Sequential Organ Failure Assessment scores. Multivariable Lasso regression analysis of predictors of complicated recovery based on microRNAs, cytokines, and chemokines revealed that miR-21-3p and monocyte chemoattractant protein-1 were predictive of complicated recovery with an area under the curve of 0.78.

CONCLUSION

Systemic microRNAs were associated with poor outcomes in PtPs, and results are consistent with previously described trends in critically ill patients. These early biomarkers of inflammation might provide predictive utility in early complicated recovery diagnosis and prognosis. Because of their potential to regulate immune responses, microRNAs may provide therapeutic targets for immunomodulation.

LEVEL OF EVIDENCE

Diagnostic Tests/Criteria; Level II.

Micro-Players of Great Significance-Host microRNA Signature in Viral Infections in Humans and Animals

Over time, more and more is becoming known about micro-players of great significance. This is particularly the case for microRNAs (miRNAs; miR), which have been found to participate in the regulation of many physiological and pathological processes in both humans and animals. One such process is viral infection in humans and animals, in which the host miRNAs—alone or in conjunction with the virus—interact on two levels: viruses may regulate the host’s miRNAs to evade its immune system, while the host miRNAs can play anti- or pro-viral roles. The purpose of this comprehensive review is to present the key miRNAs involved in viral infections in humans and animals. We summarize the data in the available literature, indicating that the signature miRNAs in human viral infections mainly include 12 miRNAs (i.e., miR-155, miR-223, miR-146a, miR-122, miR-125b, miR-132, miR-34a, miR -21, miR-16, miR-181 family, let-7 family, and miR-10a), while 10 miRNAs are commonly found in animals (i.e., miR-155, miR-223, miR-146a, miR-145, miR-21, miR-15a/miR-16 cluster, miR-181 family, let-7 family, and miR-122) in this context. Knowledge of which miRNAs are involved in different viral infections and the biological functions that they play can help in understanding the pathogenesis of viral diseases, facilitating the future development of therapeutic agents for both humans and animals.

A review on therapeutical potential of paeonol in atherosclerosis

The morbidity and mortality of atherosclerotic cardiovascular disease (ASCVD) is increasing year by year. Cortex Moutan is a traditional Chinese medicinal herb that has been widely used for thousands of years to treat a wide variety of diseases in Eastern countries due to its heat-clearing and detoxifying effects. Paeonol is a bioactive monomer extracted from Cortex Moutan, which has anti-atherosclerotic effects. In this article, we reviewed the pharmacological effects of paeonol against experimental atherosclerosis, as well as its protective effects on vascular endothelial cells, smooth muscle cells, macrophages, platelets, and other important cell types. The pleiotropic effects of paeonol in atherosclerosis suggest that it can be a promising therapeutic agent for atherosclerosis and its complications. Large-scale randomized clinical trials are warranted to elucidate whether paeonol are effective in patients with ASCVD.