Human microRNAs are processed from capped, polyadenylated transcripts that can also function as mRNAs

Plant bioactive compounds driven microRNAs (miRNAs): A potential source and novel strategy targeting gene and cancer therapeutics

Irrespective of medical technology improvements, cancer ranks among the leading causes of mortality worldwide. Although numerous cures and treatments exist, creating alternative cancer therapies with fewer adverse side effects is vital. Since ancient times, plant bioactive compounds have already been used as a remedy to heal cancer. These plant bioactive compounds and their anticancer activity can also deregulate the microRNAs (miRNAs) in the cancerous cells. Therefore, the deregulation of miRNAs in cancer cells by plant bioactive compounds and the usage of the related miRNA could be a promising approach for cancer cure, mainly to prevent cancer and overcome chemotherapeutic side effect problems. Hence, this review highlights the function of plant bioactive compounds as an anticancer agent through the underlying mechanism that alters the miRNA expression in cancer cells, ultimately leading to apoptosis. Moreover, this review provides insight into using plant bioactive compounds -driven miRNAs as an anticancer agent to develop miRNA-based cancer gene therapy. They can be the potential resource for gene therapy and novel strategies targeting cancer therapeutics.

Parkinson's Disease and MicroRNAs: A Duel Between Inhibition and Stimulation of Apoptosis in Neuronal Cells

Parkinson's disease (PD) is one of the most prevalent diseases of central nervous system that is caused by degeneration of the substantia nigra's dopamine-producing neurons through apoptosis. Apoptosis is regulated by initiators' and executioners' caspases both in intrinsic and extrinsic pathways, further resulting in neuronal damage. In that context, targeting apoptosis appears as a promising therapeutic approach for treating neurodegenerative diseases. Non-coding RNAs-more especially, microRNAs, or miRNAs-are a promising target for the therapy of neurodegenerative diseases because they are essential for a number of cellular processes, including signaling, apoptosis, cell proliferation, and gene regulation. It is estimated that a substantial portion of coding genes (more than 60%) are regulated by miRNAs. These small regulatory molecules can have wide-reaching consequences on cellular processes like apoptosis, both in terms of intrinsic and extrinsic pathways. Furthermore, it was recommended that a disruption in miRNA expression levels could also result in perturbation of typical apoptosis pathways, which may be a factor in certain diseases like PD. The latest research on miRNAs and their impact on neural cell injury in PD models by regulating the apoptosis pathway is summarized in this review article. Furthermore, the importance of lncRNA/circRNA-miRNA-mRNA network for regulating apoptosis pathways in PD models and treatment is explored. These results can be utilized for developing new strategies in PD treatment.

Small molecule and big function: MicroRNA-mediated apoptosis in rheumatoid arthritis

Rheumatoid arthritis (RA) is a common autoimmune condition and chronic inflammatory disease, mostly affecting synovial joints. The complex pathogenesis of RA is supportive of high morbidity, disability, and mortality rates. Pathological changes a common characteristic in RA synovial tissue is attributed to the inadequacy of apoptotic pathways. In that regard, apoptotic pathways have been the center of attention in RA therapeutic approaches. As the regulators in the complex network of apoptosis, microRNAs (miRNAs) are found to be vital modulators in both intrinsic and extrinsic pathways through altering their regulatory genes. Indeed, miRNA, a member of the family of non-coding RNAs, are found to be an important player in not even apoptosis, but proliferation, gene expression, signaling pathways, and angiogenesis. Aberrant expression of miRNAs is implicated in attenuation and/or intensification of various apoptosis routes, resulting in culmination of human diseases including RA. Considering the need for more studies focused on the underlying mechanisms of RA in order to elevate the unsatisfactory clinical treatments, this study is aimed to delineate the importance of apoptosis in the pathophysiology of this disease. As well, this review is focused on the critical role of miRNAs in inducing or inhibiting apoptosis of RA-synovial fibroblasts and fibroblast-like synoviocytes and how this mechanism can be exerted for therapeutic purposes for RA.

Analysis of Expression and Regulation of AKR1C2 in HPV-Positive and -Negative Oropharyngeal Squamous Cell Carcinoma

Head and Neck Squamous Cell Carcinoma (HNSCC), particularly Oropharyngeal Squamous Cell Carcinoma (OPSCC), is a major global health challenge due to its increasing incidence and high mortality rate. This study investigates the role of aldo-keto reductase 1C2 (AKR1C2) in OPSCC, focusing on its expression, correlation with Human Papillomavirus (HPV) status, oxidative stress status, and clinical outcomes, with an emphasis on sex-specific differences. We analyzed AKR1C2 expression using immunohistochemistry in formalin-fixed, paraffin-embedded tissue samples from 51 OPSCC patients. Additionally, we performed RT-qPCR in cultured HPV16-E6*I and HPV16-E6 overexpressing HEK293 cell lines (p53WT). Statistical analyses were performed to assess the correlation between AKR1C2 expression and patient data. Our results indicate a significant association between increased AKR1C2 expression and higher AJCC classification (p = 0.009) as well as positive HPV status (p = 0.008). Prognostic implications of AKR1C2 varied by sex, whereby female patients with high AKR1C2 expression had better overall survival, whereas male patients exhibited poorer outcomes. Additionally, AKR1C2 expression was linked to HPV status, suggesting a potential HPV-specific regulatory mechanism. These findings underscore the complex interplay among AKR1C2, HPV, and patient sex, highlighting the need for personalized treatment strategies for OPSCC. Targeted inhibition of AKR1C2, considering sex-specific differences, may enhance therapeutic outcomes. Future research should investigate these mechanisms to enhance treatment efficacy.

A comprehensive overview on the crosstalk between microRNAs and viral pathogenesis and infection

Infections caused by viruses as the smallest infectious agents, pose a major threat to global public health. Viral infections utilize different host mechanisms to facilitate their own propagation and pathogenesis. MicroRNAs (miRNAs), as small noncoding RNA molecules, play important regulatory roles in different diseases, including viral infections. They can promote or inhibit viral infection and have a pro-viral or antiviral role. Also, viral infections can modulate the expression of host miRNAs. Furthermore, viruses from different families evade the host immune response by producing their own miRNAs called viral miRNAs (v-miRNAs). Understanding the replication cycle of viruses and their relation with host miRNAs and v-miRNAs can help to find new treatments against viral infections. In this review, we aim to outline the structure, genome, and replication cycle of various viruses including hepatitis B, hepatitis C, influenza A virus, coronavirus, human immunodeficiency virus, human papillomavirus, herpes simplex virus, Epstein-Barr virus, Dengue virus, Zika virus, and Ebola virus. We also discuss the role of different host miRNAs and v-miRNAs and their role in the pathogenesis of these viral infections.

miR-210 in ischaemic stroke: biomarker potential, challenges and future perspectives

Ischaemic stroke, a leading cause of global morbidity and mortality, necessitates effective biomarkers for enhanced diagnostic and prognostic stratification. MicroRNAs (miRNAs), particularly miR-210, have emerged as promising candidates due to their intricate regulatory roles in cellular responses to hypoxia and neuroprotective effects. This study explores the potential of miR-210 as a biomarker for ischaemic stroke, considering its expression patterns, regulatory functions and diagnostic/prognostic implications. A literature search was conducted on PubMed, Scopus, Google Scholar and Web of Science to identify studies focusing on miR-210 in ischaemic stroke. Inclusion criteria comprised reports on miR-210 expression in ischaemic stroke patients, excluding non-English studies, reviews, commentaries and conference abstracts lacking primary data. Studies investigating miR-210 levels in ischaemic stroke patients revealed significant alterations in expression patterns compared to healthy controls. Diagnostic potential was explored, indicating miR-210's sensitivity and specificity in distinguishing ischaemic stroke from other neurological conditions. Prognostic value was evident through associations with infarct size, functional outcomes and long-term survival. Challenges included variability in miR-210 levels, limited diagnostic specificity, absence of standardised assays and concerns regarding cost-effectiveness and accessibility. While miR-210 holds promise as an ischaemic stroke biomarker, challenges must be addressed for its successful integration into clinical practice. Standardised reference ranges, validation studies in diverse populations and collaborative efforts for assay standardisation are crucial. Despite challenges, miR-210's diagnostic and prognostic potential, particularly in predicting therapeutic responses, suggests a significant role in advancing ischaemic stroke management.

MicroRNA as Key Players in Hepatocellular Carcinoma: Insights into Their Role in Metastasis

Liver cancer or hepatocellular carcinoma (HCC) remains the most common cancer in global epidemiology. Both the frequency and fatality of this malignancy have shown an upward trend over recent decades. Liver cancer is a significant concern due to its propensity for both intrahepatic and extrahepatic metastasis. Liver cancer metastasis is a multifaceted process characterized by cell detachment from the bulk tumor, modulation of cellular motility and invasiveness, enhanced proliferation, avoidance of the immune system, and spread either via lymphatic or blood vessels. MicroRNAs (miRNAs) are small non-coding ribonucleic acids (RNAs) playing a crucial function in the intricate mechanisms of tumor metastasis. A number of miRNAs can either increase or reduce metastasis via several mechanisms, such as control of motility, proliferation, attack by the immune system, cancer stem cell properties, altering the microenvironment, and the epithelial-mesenchymal transition (EMT). Besides, two other types of non-coding RNAs, such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) can competitively bind to endogenous miRNAs. This competition results in the impaired ability of the miRNAs to inhibit the expression of the specific messenger RNAs (mRNAs) that are targeted. Increasing evidence has shown that the regulatory axis comprising circRNA/lncRNA-miRNA-mRNA is correlated with the regulation of HCC metastasis. This review seeks to present a thorough summary of recent research on miRNAs in HCC, and their roles in the cellular processes of EMT, invasion and migration, as well as the metastasis of malignant cells. Finally, we discuss the function of the lncRNA/circRNA-miRNA-mRNA network as a crucial modulator of carcinogenesis and the regulation of signaling pathways or genes that are relevant to the metastasis of HCC. These findings have the potential to offer valuable insight into the discovery of novel therapeutic approaches for management of liver cancer metastasis.

MicroRNA-21 in urologic cancers: from molecular mechanisms to clinical implications

The three most common kinds of urologic malignancies are prostate, bladder, and kidney cancer, which typically cause substantial morbidity and mortality. Early detection and effective treatment are essential due to their high fatality rates. As a result, there is an urgent need for innovative research to improve the clinical management of patients with urologic cancers. A type of small noncoding RNAs of 22 nucleotides, microRNAs (miRNAs) are well-known for their important roles in a variety of developmental processes. Among these, microRNA-21 (miR-21) stands out as a commonly studied miRNA with implications in tumorigenesis and cancer development, particularly in urological tumors. Recent research has shed light on the dysregulation of miR-21 in urological tumors, offering insights into its potential as a prognostic, diagnostic, and therapeutic tool. This review delves into the pathogenesis of miR-21 in prostate, bladder, and renal cancers, its utility as a cancer biomarker, and the therapeutic possibilities of targeting miR-21.

Exploring the pathogenesis of pulmonary vascular disease

Pulmonary hypertension (PH) is a complex cardiopulmonary disorder impacting the lung vasculature, resulting in increased pulmonary vascular resistance that leads to right ventricular dysfunction. Pulmonary hypertension comprises of 5 groups (PH group 1 to 5) where group 1 pulmonary arterial hypertension (PAH), results from alterations that directly affect the pulmonary arteries. Although PAH has a complex pathophysiology that is not completely understood, it is known to be a multifactorial disease that results from a combination of genetic, epigenetic and environmental factors, leading to a varied range of symptoms in PAH patients. PAH does not have a cure, its incidence and prevalence continue to increase every year, resulting in higher morbidity and mortality rates. In this review, we discuss the different pathologic mechanisms with a focus on epigenetic modifications and their roles in the development and progression of PAH. These modifications include DNA methylation, histone modifications, and microRNA dysregulation. Understanding these epigenetic modifications will improve our understanding of PAH and unveil novel therapeutic targets, thus steering research toward innovative treatment strategies.

MicroRNAs: circulating biomarkers for the early detection of imperceptible cancers via biosensor and machine-learning advances

This review explores the topic of microRNAs (miRNAs) for improved early detection of imperceptible cancers, with potential to advance precision medicine and improve patient outcomes. Historical research exploring miRNA's role in cancer detection collectively revealed initial hurdles in identifying specific miRNA signatures for early-stage and difficult-to-detect cancers. Early studies faced challenges in establishing robust biomarker panels and overcoming the heterogeneity of cancer types. Despite this, recent developments have supported the potential of miRNAs as sensitive and specific biomarkers for early cancer detection as well as having demonstrated remarkable potential as diagnostic tools for imperceptible cancers, such as those with elusive symptoms or challenging diagnostic criteria. This review discusses the advent of high-throughput technologies that have enabled comprehensive detection and profiling of unique miRNA signatures associated with early-stage cancers. Furthermore, advancements in bioinformatics and machine-learning techniques are considered, exploring the integration of multi-omics data which have potential to enhance both the accuracy and reliability of miRNA-based cancer detection assays. Finally, perspectives on the continuing development on technologies as well as discussion around challenges that remain, such as the need for standardised protocols and addressing the complex interplay of miRNAs in cancer biology are conferred.

The Biological Roles of microRNAs in Drosophila Development

Drosophila is a well-established insect model system for studying various physiological phenomena and developmental processes, with a focus on gene regulation. Drosophila development is controlled by programmed regulatory mechanisms specific to individual tissues. When key developmental processes are shared among various insects, the associated regulatory networks are believed to be conserved across insects. Thus, studies of developmental regulation in Drosophila have substantially contributed to our understanding of insect development. Over the past two decades, studies on microRNAs (miRNAs) in Drosophila have revealed their crucial regulatory roles in various developmental processes. This review focuses on the biological roles of miRNAs in specific tissues and processes associated with Drosophila development. Additionally, as a future direction, we discuss sequencing technologies that can analyze the interactions between miRNAs and their target genes, with the aim of enhancing miRNA studies in Drosophila development.

The Multifaceted Role of miR-21 in Pancreatic Cancers

With the lack of specific signs and symptoms, pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at late metastatic stages, resulting in poor survival outcomes. Among various biomarkers, microRNA-21 (miR-21), a small non-coding RNA, is highly expressed in PDAC. By inhibiting regulatory proteins at the 3' untranslated regions (UTR), miR-21 holds significant roles in PDAC cell proliferation, epithelial-mesenchymal transition, angiogenesis, as well as cancer invasion, metastasis, and resistance therapy. We conducted a systematic search across major databases for articles on miR-21 and pancreatic cancer mainly published within the last decade, focusing on their diagnostic, prognostic, therapeutic, and biological roles. This rigorous approach ensured a comprehensive review of miR-21's multifaceted role in pancreatic cancers. In this review, we explore the current understandings and future directions regarding the regulation, diagnostic, prognostic, and therapeutic potential of targeting miR-21 in PDAC. This exhaustive review discusses the involvement of miR-21 in proliferation, epithelial-mesenchymal transition (EMT), apoptosis modulation, angiogenesis, and its role in therapy resistance. Also discussed in the review is the interplay between various molecular pathways that contribute to tumor progression, with specific reference to pancreatic ductal adenocarcinoma.

Machine Learning Strategies in MicroRNA Research: Bridging Genome to Phenome

MicroRNAs (miRNAs) have emerged as a prominent layer of regulation of gene expression. This article offers the salient and current aspects of machine learning (ML) tools and approaches from genome to phenome in miRNA research. First, we underline that the complexity in the analysis of miRNA function ranges from their modes of biogenesis to the target diversity in diverse biological conditions. Therefore, it is imperative to first ascertain the miRNA coding potential of genomes and understand the regulatory mechanisms of their expression. This knowledge enables the efficient classification of miRNA precursors and the identification of their mature forms and respective target genes. Second, and because one miRNA can target multiple mRNAs and vice versa, another challenge is the assessment of the miRNA-mRNA target interaction network. Furthermore, long-noncoding RNA (lncRNA)and circular RNAs (circRNAs) also contribute to this complexity. ML has been used to tackle these challenges at the high-dimensional data level. The present expert review covers more than 100 tools adopting various ML approaches pertaining to, for example, (1) miRNA promoter prediction, (2) precursor classification, (3) mature miRNA prediction, (4) miRNA target prediction, (5) miRNA- lncRNA and miRNA-circRNA interactions, (6) miRNA-mRNA expression profiling, (7) miRNA regulatory module detection, (8) miRNA-disease association, and (9) miRNA essentiality prediction. Taken together, we unpack, critically examine, and highlight the cutting-edge synergy of ML approaches and miRNA research so as to develop a dynamic and microlevel understanding of human health and diseases.

miRNAs as Interconnectors between Obesity and Cancer

Obesity and cancer are a concern of global interest. It is proven that obesity may trigger the development or progression of some types of cancer; however, the connection by non-coding RNAs has not been totally explored. In the present review, we discuss miRNAs and lncRNAs dysregulation involved in obesity and some cancers, shedding light on how these conditions may exacerbate one another through the dysregulation of ncRNAs. lncRNAs have been reported as regulating microRNAs. An in silico investigation of lncRNA and miRNA interplay is presented. Our investigation revealed 44 upregulated and 49 downregulated lncRNAs in obesity and cancer, respectively. miR-375, miR-494-3p, miR-1908, and miR-196 were found interacting with 1, 4, 4 and 4 lncRNAs, respectively, which are involved in PPARγ cell signaling regulation. Additionally, miR-130 was found to be downregulated in obesity and reported as modulating 5 lncRNAs controlling PPARγ cell signaling. Similarly, miR-128-3p and miR-143 were found to be downregulated in obesity and cancer, interacting with 5 and 4 lncRNAs, respectively, associated with MAPK cell signaling modulation. The delicate balance between miRNA and lncRNA expression emerges as a critical determinant in the development of obesity-associated cancers, presenting these molecules as promising biomarkers. However, additional and deeper studies are needed to reach solid conclusions about obesity and cancer connection by ncRNAs.

Epigenetic regulations in Mycobacterium tuberculosis infection

Mycobacterium tuberculosis (Mtb) employs several sophisticated strategies to evade host immunity and facilitate its intracellular survival. One of them is the epigenetic manipulation of host chromatin by three strategies i.e., DNA methylation, histone modifications and miRNA involvement. A host-directed therapeutic can be an attractive approach that targets these host epigenetics or gene regulations and circumvent manipulation of host cell machinery by Mtb. Given the complexity of the nature of intracellular infection by Mtb, there are challenges in identifying the important host proteins, non-coding RNA or the secretory proteins of Mtb itself that directly or indirectly bring upon the epigenetic modifications in the host chromatin. Equally challenging is developing the methods of targeting these epigenetic factors through chemical or non-chemical approaches as host-directed therapeutics. The current review article briefly summarizes several of the epigenetic factors that serve to bring upon potential changes in the host transcriptional machinery and targets the immune system for immunosuppression and disease progression in Mtb infection.

Decoding the Versatile Landscape of Autophagic Protein VMP1 in Cancer: A Comprehensive Review across Tissue Types and Regulatory Mechanisms

Autophagy, a catabolic process orchestrating the degradation of proteins and organelles within lysosomes, is pivotal for maintaining cellular homeostasis. However, its dual role in cancer involves preventing malignant transformation while fostering progression and therapy resistance. Vacuole Membrane Protein 1 (VMP1) is an essential autophagic protein whose expression, per se, triggers autophagy, being present in the whole autophagic flux. In pancreatic cancer, VMP1-whose expression is linked to the Kirsten Rat Sarcoma Virus (KRAS) oncogene-significantly contributes to disease promotion, progression, and chemotherapy resistance. This investigation extends to breast cancer, colon cancer, hepatocellular carcinoma, and more, highlighting VMP1's nuanced nature, contingent on specific tissue contexts. The examination of VMP1's interactions with micro-ribonucleic acids (miRNAs), including miR-21, miR-210, and miR-124, enhances our understanding of its regulatory network in cancer. Additionally, this article discusses VMP1 gene fusions, especially with ribosomal protein S6 kinase B1 (RPS6KB1), shedding light on potential implications for tumor malignancy. By deciphering the molecular mechanisms linking VMP1 to cancer progression, this exploration paves the way for innovative therapeutic strategies to disrupt these pathways and potentially improve treatment outcomes.

Expression of circulating oar-miR-485-5p and oar-miR-493-5p during the estrous cycle and early pregnancy in ovine plasma

In the current study, we aimed to assess the expression levels of two circulating microRNAs (miRNA) (oar-miR-485-5p and oar-miR-493-5p) in the ovine plasma during the peri-implantation. After mating, we collected the plasma samples from a total of 8 ewes on day 22 of pregnancy (P22; n = 4) and day 22 of the estrous cycle (C22; n=4). We used mature miRNA sequences for oar-miR-485-5p and oar-miR-493-5p out of one hundred fifty, which were retrieved from our microarray results of previous study. We showed that the miRNA expression of oar-miR-485-5p and oar-miR-493-5p were upregulated in P22 (P<0.05) when compared to C22. Those two miRNAs targeted 311 target genes in the peri-implantation period of pregnancy. Furthermore, we revealed 151 GO/pathway terms in biological process (BP) and 25 GO/pathway terms in molecular function (MF), while we demonstrated 13 GO/pathway terms in cellular component (CC). We revealed three hub genes as interleukin 2 (IL2), interleukin 18 (IL18), and C-X-C Motif Chemokine Ligand 10 (CXCL10). In conclusion, both miR-485-5p and oar-miR-493-5p have the potential to be a biomarker to understand peri-implantation of the ovine pregnancy in the aspect of pregnancy-reflected changes in maternal plasma.

Target-directed microRNA degradation: Mechanisms, significance, and functional implications

MicroRNAs (miRNAs) are small non-coding RNAs that play a fundamental role in enabling miRNA-mediated target repression, a post-transcriptional gene regulatory mechanism preserved across metazoans. Loss of certain animal miRNA genes can lead to developmental abnormalities, disease, and various degrees of embryonic lethality. These short RNAs normally guide Argonaute (AGO) proteins to target RNAs, which are in turn translationally repressed and destabilized, silencing the target to fine-tune gene expression and maintain cellular homeostasis. Delineating miRNA-mediated target decay has been thoroughly examined in thousands of studies, yet despite these exhaustive studies, comparatively less is known about how and why miRNAs are directed for decay. Several key observations over the years have noted instances of rapid miRNA turnover, suggesting endogenous means for animals to induce miRNA degradation. Recently, it was revealed that certain targets, so-called target-directed miRNA degradation (TDMD) triggers, can "trigger" miRNA decay through inducing proteolysis of AGO and thereby the bound miRNA. This process is mediated in animals via the ZSWIM8 ubiquitin ligase complex, which is recruited to AGO during engagement with triggers. Since its discovery, several studies have identified that ZSWIM8 and TDMD are indispensable for proper animal development. Given the rapid expansion of this field of study, here, we summarize the key findings that have led to and followed the discovery of ZSWIM8-dependent TDMD. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA in Disease and Development > RNA in Development.

RNA Interference in Insects: From a Natural Mechanism of Gene Expression Regulation to a Biotechnological Crop Protection Promise

Insect pests rank among the major limiting factors in agricultural production worldwide. In addition to direct effect on crops, some phytophagous insects are efficient vectors for plant disease transmission. Large amounts of conventional insecticides are required to secure food production worldwide, with a high impact on the economy and environment, particularly when beneficial insects are also affected by chemicals that frequently lack the desired specificity. RNA interference (RNAi) is a natural mechanism gene expression regulation and protection against exogenous and endogenous genetic elements present in most eukaryotes, including insects. Molecules of double-stranded RNA (dsRNA) or highly structured RNA are the substrates of cellular enzymes to produce several types of small RNAs (sRNAs), which play a crucial role in targeting sequences for transcriptional or post-transcriptional gene silencing. The relatively simple rules that underlie RNAi regulation, mainly based in Watson-Crick complementarity, have facilitated biotechnological applications based on these cellular mechanisms. This includes the promise of using engineered dsRNA molecules, either endogenously produced in crop plants or exogenously synthesized and applied onto crops, as a new generation of highly specific, sustainable, and environmentally friendly insecticides. Fueled on this expectation, this article reviews current knowledge about the RNAi pathways in insects, and some other applied questions such as production and delivery of recombinant RNA, which are critical to establish RNAi as a reliable technology for insect control in crop plants.

Identification of Tissue miRNA Signatures for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC), a neoplasm of the gastrointestinal tract, is the most common pancreatic malignancy (90%) and the fourth highest cause of cancer mortality worldwide. Surgery intervention is currently the only strategy able to offer an advantage in terms of overall survival, but prognosis remains poor even for operated patients. Therefore, the development of robust biomarkers for early diagnosis and prognostic stratification in clinical practice is urgently needed. In this work, we investigated deregulated microRNAs (miRNAs) in tissues from PDAC patients with high (G3) or low (G2) histological grade and with (N+) or without (N-) lymph node metastases. miRNA expression profiling was performed by a comprehensive PCR array and subsequent validation by RT-qPCR. The results showed a significant increase in miR-1-3p, miR-31-5p, and miR-205-5p expression in G3 compared to G2 patients (** p < 0.01; *** p < 0.001; *** p < 0.001). miR-518d-3p upregulation and miR-215-5p downregulation were observed in N+ compared to N- patients. A statistical analysis performed using OncomiR program showed the significant involvement (p < 0.05) of two miRNAs (miR-31 and miR-205) in the histological grade of PDAC patients. Also, an expression analysis in PDAC patients showed that miR-31 and miR-205 had the highest expression at grade 3 compared with normal and other tumor grades. Overall, survival plots confirmed that the overexpression of miR-31 and miR-205 was significantly correlated with decreased survival in TCGA PDAC clinical samples. A KEGG pathway analysis showed that all three miRNAs are involved in the regulation of multiple pathways, including the Hippo signaling, adherens junction and microRNAs in cancer, along with several target genes. Based on in silico analysis and experimental validation, our study suggests the potential role of miR-1-3p, miR-31-5p, and miR-205-5p as useful clinical biomarkers and putative therapeutic targets in PDAC, which should be further investigated to determine the specific molecular processes affected by their aberrant expression.

The interplay of miRNAs and ferroptosis in diseases related to iron overload

Ferroptosis has been conceptualized as a novel cell death modality distinct from apoptosis, necroptosis, pyroptosis and autophagic cell death. The sensitivity of cellular ferroptosis is regulated at multiple layers, including polyunsaturated fatty acid metabolism, glutathione-GPX4 axis, iron homeostasis, mitochondria and other parallel pathways. In addition, microRNAs (miRNAs) have been implicated in modulating ferroptosis susceptibility through targeting different players involved in the execution or avoidance of ferroptosis. A growing body of evidence pinpoints the deregulation of miRNA-regulated ferroptosis as a critical factor in the development and progression of various pathophysiological conditions related to iron overload. The revelation of mechanisms of miRNA-dependent ferroptosis provides novel insights into the etiology of diseases and offers opportunities for therapeutic intervention. In this review, we discuss the interplay of emerging miRNA regulators and ferroptosis players under different pathological conditions, such as cancers, ischemia/reperfusion, neurodegenerative diseases, acute kidney injury and cardiomyopathy. We emphasize on the relevance of miRNA-regulated ferroptosis to disease progression and the targetability for therapeutic interventions.

If the 5' cap fits (wear it) - Non-canonical RNA capping

RNA capping is a prominent RNA modification that influences RNA stability, metabolism, and function. While it was long limited to the study of the most abundant eukaryotic canonical m7G cap, the field recently went through a large paradigm shift with the discovery of non-canonical RNA capping in bacteria and ultimately all domains of life. The repertoire of non-canonical caps has expanded to encompass metabolite caps, including NAD, FAD, CoA, UDP-Glucose, and ADP-ribose, alongside alarmone dinucleoside polyphosphate caps, and methylated phosphate cap-like structures. This review offers an introduction into the field, presenting a summary of the current knowledge about non-canonical RNA caps. We highlight the often still enigmatic biological roles of the caps together with their processing enzymes, focusing on the most recent discoveries. Furthermore, we present the methods used for the detection and analysis of these non-canonical RNA caps and thus provide an introduction into this dynamic new field.

Vector-Mediated Delivery of Transgenes and RNA Interference-Based Gene Silencing Sequences to Astrocytes for Disease Management: Advances and Prospectives

Astrocytes are a type of important glial cell in the brain that serve crucial functions in regulating neuronal activity, facilitating communication between neurons, and keeping everything in balance. In this abstract, we explore current methods and future approaches for using vectors to precisely target astrocytes in the fight against various illnesses. In order to deliver therapeutic cargo selectively to astrocytes, researchers have made tremendous progress by using viral vectors such as adeno-associated viruses (AAVs) and lentiviruses. It has been established that engineered viral vectors are capable of either crossing the blood-brain barrier (BBB) or being delivered intranasally, which facilitates their entrance into the brain parenchyma. These vectors are able to contain transgenes that code for neuroprotective factors, synaptic modulators, or anti-inflammatory medicines, which pave the way for multiple approaches to disease intervention. Strategies based on RNA interference (RNAi) make vector-mediated astrocyte targeting much more likely to work. Small interfering RNAs (siRNAs) and short hairpin RNAs (shRNAs) are two types of RNA that can be made to silence disease-related genes in astrocytes. Vector-mediated delivery in conjunction with RNAi techniques provides a powerful toolkit for investigating the complex biological pathways that contribute to disease development. However, there are still a number of obstacles to overcome in order to perfect the specificity, safety, and duration of vector-mediated astrocyte targeting. In order to successfully translate research findings into clinical practise, it is essential to minimise off-target effects and the risk of immunogenicity. To demonstrate the therapeutic effectiveness of these strategies, rigorous preclinical investigation and validation are required.

A Comprehensive Review on the Importance of MiRNA-206 in the Animal Model and Human Diseases

MicroRNA-206 (miR-206) is a microRNA that is involved in many human diseases, such as myasthenia gravis, osteoarthritis, depression, cancers, etc. Both inhibition effects and progression roles of miR-206 have been reported for the past few years. High expression of miR-206 was observed in patients with osteoarthritis, gastric cancer and epithelial ovarian cancer compared to normal people. The study also showed that miR-206 promotes cancer progression in breast cancer patients and avascular necrosis of the femoral head. Meanwhile, several studies have shown that expression levels of miR-206 were down-regulated in laryngeal carcinoma cell multiplication, as well as in hepatocellular carcinoma, non-small lung cancer and infantile hemangioma. Moreover, miR-206 was up-regulated in the mild stage of amyotrophic lateral sclerosis patients and then down-regulated in the moderate and severe stages, indicating that miR-206 has the double effects of starting and aggravating the disease. In neuropsychiatric disorders, such as depression, miR-206 also plays an important role in the progression of the disease; the level of miR-206 is most highly expressed in the brains of patients with depression. In the current review, we summarize the role of miR-206 in various diseases, and miR-206 may be developed as a new biomarker for diagnosing diseases in the near future.

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 microRNAs Expression during Cancer Development, and Chemoprevention by Natural Compounds: A Comprehensive Review

MicroRNAs are short non-coding RNAs that inhibit gene expression at the post-transcriptional level. Abnormal microRNA expression has been associated with different human diseases, including cancer. Epigenetic changes, mutation, transcriptional deregulation, DNA copy number abnormalities, and defects in the biogenesis machinery play an important role in abnormal microRNA expression. Modulation of microRNAs by natural agents has emerged to enhance the efficacy of conventional chemotherapy through combinatorial therapeutic approach. This review summarizes the current understanding of abnormal microRNA expression in cancer, the different cellular mechanisms of microRNA, and their prevention by natural compounds. Understanding microRNA expression patterns during cancer development may help to identify stage-specific molecular markers. Natural compounds that exert regulatory effects by modulating microRNAs can be used in better cancer chemopreventive strategies by directly targeting microRNAs or as a way to increase sensitivity to existing chemotherapy regimens.

miRNA contributes to neuropathic pains

Neuropathic pain (NP) is a kind of chronic pain caused by direct injury to the peripheral or central nervous system (CNS). microRNAs (miRNAs) are small noncoding RNAs that mostly interact with the 3 untranslated region of messenger RNAs (mRNAs) to regulate the expression of multiple genes. NP is characterized by changes in the expression of receptors and mediators, and there is evidence that miRNAs may contribute to some of these alterations. In this review, we aimed to fully comprehend the connection between NP and miRNA; and also, to establish a link between neurology, biology, and dentistry. Studies have shown that targeting miRNAs may be an effective therapeutic strategy for the treatment of chronic pain and potential target for the prevention of NP.

MicroRNA-183 cluster: a promising biomarker and therapeutic target in gastrointestinal malignancies

Small non-coding RNAs (microRNA, miR), powerful epigenetic regulators, were found involved in the regulation of most biological functions via post-translational inhibition of protein expression. Increased expression of pro-oncogenic miRs (known as miR cancer biomarkers) and inhibition of pro-apoptotic miR expression have been demonstrated in different tumors. The recently identified miR-183 was found implicated in gastrointestinal tumor metabolism regulation. Elevated miR-183 expression and cancer-promoting effects were reported in esophageal and colorectal cancers, which was partially contradicted by controversial data observed in gastric cancers. Anti-cancer effect of miR-183 in gastric cancer cells was associated with the Bim-1 and Ezrin genes regulation. Many studies indicated that miR-183 can inhibit tumor suppressor genes in most cell lines, promoting tumor cell proliferation and migration. Increased miR-183 level results in the downregulation of FOXO1, PDCD4, and other tumor suppressor genes in gastrointestinal tumor cells. MiR-183 also influences the signaling of PI3K/AKT/mTOR, Wnt/β-catenin, and Bcl-2/p53 signaling pathways. Mir-183 inhibits apoptosis and autophagy, and promotes epithelial-to-mesenchymal transition, cancer cell proliferation, and migration. Accordingly, gastrointestinal cancer occurrence, development of chemoradiotherapy resistance, recurrence/metastasis, and prognosis were associated with miR-183 expression. The current study assessed reported miR-183 functions and signaling, providing new insights for the diagnosis and treatment of gastrointestinal malignancies.

Transforming growth factor-beta superfamily regulates mesenchymal stem cell osteogenic differentiation: A microRNA linking

The ability to differentiate into cells of different lineages, such as bone cells, is the principal value of adult mesenchymal stem cells (MSCs), which can be used with the final aim of regenerating damaged tissue. Due to its potential use and importance in regenerative medicine and tissue engineering, several questions have been raised regarding the molecular mechanisms of MSC differentiation. As one of the crucial mediators in organism development, the transforming growth factor-beta (TGF-β) superfamily directs MSCs' commitment to selecting differentiation pathways. This review aims to give an overview of the current knowledge on the mechanisms of the TGF-β superfamily in MSCs bone differentiation, with additional insight into the mutual regulation of microRNAs and TGF-β in osteogenesis.

Integrated small RNA, mRNA and protein omics reveal a miRNA network orchestrating metabolic maturation of the developing human heart

BACKGROUND

As the fetal heart develops, cardiomyocyte proliferation potential decreases while fatty acid oxidative capacity increases in a highly regulated transition known as cardiac maturation. Small noncoding RNAs, such as microRNAs (miRNAs), contribute to the establishment and control of tissue-specific transcriptional programs. However, small RNA expression dynamics and genome-wide miRNA regulatory networks controlling maturation of the human fetal heart remain poorly understood.

RESULTS

Transcriptome profiling of small RNAs revealed the temporal expression patterns of miRNA, piRNA, circRNA, snoRNA, snRNA and tRNA in the developing human heart between 8 and 19 weeks of gestation. Our analysis demonstrated that miRNAs were the most dynamically expressed small RNA species throughout mid-gestation. Cross-referencing differentially expressed miRNAs and mRNAs predicted 6200 mRNA targets, 2134 of which were upregulated and 4066 downregulated as gestation progressed. Moreover, we found that downregulated targets of upregulated miRNAs, including hsa-let-7b, miR-1-3p, miR-133a-3p, miR-143-3p, miR-499a-5p, and miR-30a-5p predominantly control cell cycle progression. In contrast, upregulated targets of downregulated miRNAs, including hsa-miR-1276, miR-183-5p, miR-1229-3p, miR-615-3p, miR-421, miR-200b-3p and miR-18a-3p, are linked to energy sensing and oxidative metabolism. Furthermore, integrating miRNA and mRNA profiles with proteomes and reporter metabolites revealed that proteins encoded in mRNA targets and their associated metabolites mediate fatty acid oxidation and are enriched as the heart develops.

CONCLUSIONS

This study presents the first comprehensive analysis of the small RNAome of the maturing human fetal heart. Our findings suggest that coordinated activation and repression of miRNA expression throughout mid-gestation is essential to establish a dynamic miRNA-mRNA-protein network that decreases cardiomyocyte proliferation potential while increasing the oxidative capacity of the maturing human fetal heart. Our results provide novel insights into the molecular control of metabolic maturation of the human fetal heart.

miRNA in head and neck squamous cell carcinomas: promising but still distant future of personalized oncology

Head and neck squamous cell carcinoma is one of the most common and fatal cancers worldwide. Lack of appropriate preventive screening tests, late detection, and high heterogeneity of these tumors are the main reasons for the unsatisfactory effects of therapy and, consequently, unfavorable outcomes for patients. An opportunity to improve the quality of diagnostics and treatment of this group of cancers are microRNAs (miRNAs) - molecules with a great potential both as biomarkers and therapeutic targets. This review aims to present the characteristics of these short non-coding RNAs (ncRNAs) and summarize the current reports on their use in oncology focused on medical strategies tailored to patients' needs.

Prospects of microRNAs as therapeutic biomarkers in non-small cell lung cancer

Lung Cancer, the second most common cancer worldwide, remains the leading cause of cancer-related deaths, contemporarily. More than 85% of identified lung cancer cases are comprised of non-small-cell lung carcinoma (NSCLC). Despite the best advancements in the realm of NSCLC therapy, the five-year survival period of NSCLC patients remains unchanged. Underlying complex molecular heterogeneity, delay in early detection resulting in progression of the disease to its advanced stage and acquired resistance of NSCLC cells during therapy have posed additional challenges for circumventing the discrepancies in treatment strategy. microRNAs (miRNAs) are a class of non-coding RNAs, identified as molecules playing an indispensable role in tumorigenesis & progression and metastasis of several cancers, including NSCLC, either by possessing tumor suppressor or by oncogenic functions. As observed across several studies, miRNA dysregulation has been recognised as a causative mechanism behind NSCLC tumorigenesis. In this review, we discuss the role of miRNAs in NSCLC tumor progression caused by their dysregulation, thereby stating their potential therapeutic application in NSCLC as therapeutic biomarkers. We have also highlighted the recent findings of some of the most widely studied tumor suppressor (miR-486, miR-7 miR-34), and oncogene miRNAs (miR-21, miR-224, miR-135b) that can be further explored for its therapeutic potentialities in the management of NSCLC.

Post-transcriptional gene silencing in a dynamic RNP world

MicroRNA (miRNA)-guided gene silencing is a key regulatory process in various organisms and linked to many human diseases. MiRNAs are processed from precursor molecules and associate with Argonaute proteins to repress the expression of complementary target mRNAs. Excellent work by numerous labs has contributed to a detailed understanding of the mechanisms of miRNA function. However, miRNA effects have mostly been analyzed and viewed as isolated events and their natural environment as part of complex RNA-protein particles (RNPs) is often neglected. RNA binding proteins (RBPs) regulate key enzymes of the miRNA processing machinery and furthermore RBPs or readers of RNA modifications may modulate miRNA activity on mRNAs. Such proteins may function similarly to miRNAs and add their own contributions to the overall expression level of a particular gene. Therefore, post-transcriptional gene regulation might be more the sum of individual regulatory events and should be viewed as part of a dynamic and complex RNP world.

mRNA splicing is modulated by intronic microRNAs

Splicing of transcripts is catalyzed by the spliceosome, a mega-complex consisting of hundreds of proteins and five snRNAs, which employs direct interactions. When U1 snRNA forms high-affinity binding, namely more than eight base pairs, with the 5'SS, the result is usually a suppressing effect on the splicing activity. This likely occurs due to the inefficient unwinding of U1/5'SS base-pairing or other regulatory obstructions. Here, we show in vitro and in patient-derived cell lines that pre-microRNAs can modulate the splicing reaction by interacting with U1 snRNA. This leads to reduced binding affinity to the 5'SS, and hence promotes the inclusion of exons containing 5'SS, despite sequence-based high affinity to U1. Application of the mechanism resulted in correction of the splicing defect in the disease-causing VCAN gene from an individual with Wagner syndrome. This pre-miRNA/U1 interaction can regulate the expression of alternatively spliced exons, thus extending the scope of mechanisms regulating splicing.

Insight into the Epigenetics of Kaposi's Sarcoma-Associated Herpesvirus

Epigenetic reprogramming represents a series of essential events during many cellular processes including oncogenesis. The genome of Kaposi's sarcoma-associated herpesvirus (KSHV), an oncogenic herpesvirus, is predetermined for a well-orchestrated epigenetic reprogramming once it enters into the host cell. The initial epigenetic reprogramming of the KSHV genome allows restricted expression of encoded genes and helps to hide from host immune recognition. Infection with KSHV is associated with Kaposi's sarcoma, multicentric Castleman's disease, KSHV inflammatory cytokine syndrome, and primary effusion lymphoma. The major epigenetic modifications associated with KSHV can be labeled under three broad categories: DNA methylation, histone modifications, and the role of noncoding RNAs. These epigenetic modifications significantly contribute toward the latent-lytic switch of the KSHV lifecycle. This review gives a brief account of the major epigenetic modifications affiliated with the KSHV genome in infected cells and their impact on pathogenesis.

Stress response abnormalities transgenerationally inherited via miR-23 downregulation are restored by a methyl modulator during the lactation period

Low birthweight rats due to fetal undernutrition sustain higher corticosterone levels when exposed to stress. This is due to the upregulated expression of the pituitary-specific Gas5, a long noncoding RNA (lncRNA) that acts as a glucocorticoid receptor decoy and then competitively inhibiting the binding of glucocorticoids to DNA. However, the mechanism of Gas5 lncRNA upregulation remains unclear. Therefore, using the fetal undernourished model, we identified the factors that regulated Gas5 lncRNA expression and examined their effect on subsequent generations. We found that the expression levels of miR-23 was significantly lower in low birth-weight rats compared with controls. The expression of miR-23 was significantly lower and the expression levels of Gas5 lncRNA were significantly higher in the pituitary gland of low birth-weight offspring of the F2 and F3 generations compared with controls. The methyl modulator intervention in lactating F0 maternal rats restored miR-23 and Gas5 lncRNA expressions not only in F1, F2 and F3 offspring. Moreover, the intervention reduced circulating corticosterone levels and gene expressions in the pituitary gland after restraint stress exposure. In conclusion, miR-23-mediated alterations of the stress response are inherited and restored by methyl modulator intervention during lactation.

The Role of MicroRNAs in Breast Cancer and the Challenges of Their Clinical Application

MicroRNAs (miRNAs) constitute a subclass of non-coding RNAs that exert substantial influence on gene-expression regulation. Their tightly controlled expression plays a pivotal role in various cellular processes, while their dysregulation has been implicated in numerous pathological conditions, including cancer. Among cancers affecting women, breast cancer (BC) is the most prevalent malignant tumor. Extensive investigations have demonstrated distinct expression patterns of miRNAs in normal and malignant breast cells. Consequently, these findings have prompted research efforts towards leveraging miRNAs as diagnostic tools and the development of therapeutic strategies. The aim of this review is to describe the role of miRNAs in BC. We discuss the identification of oncogenic, tumor suppressor and metastatic miRNAs among BC cells, and their impact on tumor progression. We describe the potential of miRNAs as diagnostic and prognostic biomarkers for BC, as well as their role as promising therapeutic targets. Finally, we evaluate the current use of artificial intelligence tools for miRNA analysis and the challenges faced by these new biomedical approaches in its clinical application. The insights presented in this review underscore the promising prospects of utilizing miRNAs as innovative diagnostic, prognostic, and therapeutic tools for the management of BC.

Modulation of the Cellular microRNA Landscape: Contribution to the Protective Effects of High-Density Lipoproteins (HDL)

High-density lipoproteins (HDL) play an established role in protecting against cellular dysfunction in a variety of different disease contexts; however, harnessing this therapeutic potential has proved challenging due to the heterogeneous and relative instability of this lipoprotein and its variable cargo molecules. The purpose of this study is to examine the contribution of microRNA (miRNA; miR) sequences, either delivered directly or modulated endogenously, to these protective functions. This narrative review introduces the complex cargo carried by HDL, the protective functions associated with this lipoprotein, and the factors governing biogenesis, export and the uptake of microRNA. The possible mechanisms by which HDL can modulate the cellular miRNA landscape are considered, and the impact of key sequences modified by HDL is explored in diseases such as inflammation and immunity, wound healing, angiogenesis, dyslipidaemia, atherosclerosis and coronary heart disease, potentially offering new routes for therapeutic intervention.

The pivotal role of EMT-related noncoding RNAs regulatory axes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains a major health problem worldwide, being the leading cause of cancer-related deaths, with limited treatment options, especially in its advanced stages. Tumor resistance is closely associated with the activation of the EMT phenomenon and its reversal, being modulated by different molecules, including noncoding RNAs (ncRNAs). Noncoding RNAs have the potential to function as both tumor suppressors and oncogenic molecules, controlling the malignant potential of HCC cells. Basically, these molecules circulate in the tumor microenvironment, encapsulated in exosomes. Their impact on cell biology is more significant than originally expected, which makes related research rather complex. The temporal and spatial expression patterns, precise roles and mechanisms of specific ncRNAs encapsulated in exosomes remain primarily unknown in different stages of the disease. This review aims to highlight the recent advances in ncRNAs related to EMT and classifies the described mechanism as direct and indirect, for a better summarization. Moreover, we provide an overview of current research on the role of ncRNAs in several drug resistance-related pathways, including the emergence of resistance to sorafenib, doxorubicin, cisplatin and paclitaxel therapy. Nevertheless, we comprehensively discuss the underlying regulatory mechanisms of exosomal ncRNAs in EMT-HCC via intercellular communication pathways.

The dysregulation of miRNAs in epilepsy and their regulatory role in inflammation and apoptosis

Epilepsy is a neurological disorder that impacts millions of people worldwide, and it is characterized by the occurrence of recurrent seizures. The pathogenesis of epilepsy is complex, involving dysregulation of various genes and signaling pathways. MicroRNAs (miRNAs) are a group of small non-coding RNAs that play a vital role in the regulation of gene expression. They have been found to be involved in the pathogenesis of epilepsy, acting as key regulators of neuronal excitability and synaptic plasticity. In recent years, there has been a growing interest in exploring the miRNA regulatory network in epilepsy. This review summarizes the current knowledge of the regulatory miRNAs involved in inflammation and apoptosis in epilepsy and discusses its potential as a new avenue for developing targeted therapies for the treatment of epilepsy.

Influenza a virus regulates interferon signaling and its associated genes; MxA and STAT3 by cellular miR-141 to ensure viral replication

The antiviral response against influenza A virus (IAV) infection includes the induction of the interferon (IFN) signaling pathway, including activation of the STATs protein family. Subsequently, antiviral myxovirus resistance (MxA) protein and other interferon-stimulated genes control virus replication; however, the molecular interaction of viral-mediated IFN signaling needs more investigation. Host microRNAs (miRNAs) are small non-coding molecules that posttranscriptionally regulate gene expression. Here, we sought to investigate the possible involvement of miR-141 in IAV-mediated IFN signaling. Accordingly, the microarray analysis of A549 cells transfected with precursor miR-141 (pre-miR-141) was used to capture the potentially regulated genes in response to miR-141 overexpression independent of IAV infection. The downregulation of targeted genes by miR-141, in addition to viral gene expression, was investigated by quantitative real-time PCR, western blot analysis, and flow cytometric assay. Our findings showed a significant upregulation of miR-141 in infected A549 cells with different strains of IAV. Notably, IAV replication was firmly interrupted in cells transfected with the miR-141 inhibitor. While its replication significantly increased in cells transfected with pre-miR-141 confirming the crucial role of miRNA-141 in supporting virus replication. Interestingly, the microarray data of miR-141 transduced A549 cells showed many downregulated genes, including MxA, STAT3, IFI27, and LAMP3. The expression profile of MxA and STAT3 was significantly depleted in infected cells transfected with the pre-miR-141, while their expression was restored in infected cells transfected with the miR-141 inhibitor. Unlike interleukin 6 (IL-6), the production of IFN-β markedly decreased in infected cells that transfected with pre-miR-141, while it significantly elevated in infected cells transfected with miR-141 inhibitor. These data provide evidence for the crucial role of miR-141 in regulating the antiviral gene expression induced by IFN and IL-6 signaling during IAV infection to ensure virus replication.

Angiogenesis and prostate cancer: MicroRNAs comes into view

Angiogenesis, the formation of new blood vessels, is an important stage in the growth of cancer. Extracellular matrix, endothelial cells, and soluble substances must be carefully coordinated during the multistep procedure of angiogenesis. Inducers and inhibitors have been found to control pretty much every phase. In addition to benign prostatic hyperplasia, prostatic intraepithelial neoplasia, and angiogenesis have a critical role in the initiation and progression of prostate cancer. MicroRNA (miRNA) is endogenous, short, non-coding RNA molecules of almost 22 nucleotides play a role in regulating cellular processes and regulating several genes' expression. Through controlling endothelial migration, differentiation, death, and cell proliferation, miRNAs have a significant function in angiogenesis. A number of pathological and physiological processes, particularly prostate cancer's emergence, depend on the regulation of angiogenesis. Investigating the functions played with miRNAs in angiogenesis is crucial because it might result in the creation of novel prostate cancer therapies that entail regulating angiogenesis. The function of several miRNAs and its targeting genes engaged in cancer of the prostate angiogenesis will be reviewed in this review in light of the most recent developments. The potential clinical utility of miRNAs potentially a novel therapeutic targets will also be explored, as well as their capacity to control prostate cancer angiogenesis and the underlying mechanisms.

Unraveling Therapeutic Opportunities and the Diagnostic Potential of microRNAs for Human Lung Cancer

Lung cancer is a major public health problem and a leading cause of cancer-related deaths worldwide. Despite advances in treatment options, the five-year survival rate for lung cancer patients remains low, emphasizing the urgent need for innovative diagnostic and therapeutic strategies. MicroRNAs (miRNAs) have emerged as potential biomarkers and therapeutic targets for lung cancer due to their crucial roles in regulating cell proliferation, differentiation, and apoptosis. For example, miR-34a and miR-150, once delivered to lung cancer via liposomes or nanoparticles, can inhibit tumor growth by downregulating critical cancer promoting genes. Conversely, miR-21 and miR-155, frequently overexpressed in lung cancer, are associated with increased cell proliferation, invasion, and chemotherapy resistance. In this review, we summarize the current knowledge of the roles of miRNAs in lung carcinogenesis, especially those induced by exposure to environmental pollutants, namely, arsenic and benzopyrene, which account for up to 1/10 of lung cancer cases. We then discuss the recent advances in miRNA-based cancer therapeutics and diagnostics. Such information will provide new insights into lung cancer pathogenesis and innovative diagnostic and therapeutic modalities based on miRNAs.

Conservation and Targets of miR-71: A Systematic Review and Meta-Analysis

MicroRNAs (miRNAs) perform a pivotal role in the regulation of gene expression across the animal kingdom. As negative regulators of gene expression, miRNAs have been shown to function in the genetic pathways that control many biological processes and have been implicated in roles in human disease. First identified as an aging-associated gene in C. elegans, miR-71, a miRNA, has a demonstrated capability of regulating processes in numerous different invertebrates, including platyhelminths, mollusks, and insects. In these organisms, miR-71 has been shown to affect a diverse range of pathways, including aging, development, and immune response. However, the exact mechanisms by which miR-71 regulates these pathways are not completely understood. In this paper, we review the identified functions of miR-71 across multiple organisms, including identified gene targets, pathways, and the conditions which affect regulatory action. Additionally, the degree of conservation of miR-71 in the evaluated organisms and the conservation of their predicted binding sites in target 3' UTRs was measured. These studies may provide an insight on the patterns, interactions, and conditions in which miR-71 is able to exert genotypic and phenotypic influence.

Unraveling the epigenetic landscape of pulmonary arterial hypertension: implications for personalized medicine development

Pulmonary arterial hypertension (PAH) is a multifactorial disease associated with the remodeling of pulmonary blood vessels. If left unaddressed, PAH can lead to right heart failure and even death. Multiple biological processes, such as smooth muscle proliferation, endothelial dysfunction, inflammation, and resistance to apoptosis, are associated with PAH. Increasing evidence suggests that epigenetic factors play an important role in PAH by regulating the chromatin structure and altering the expression of critical genes. For example, aberrant DNA methylation and histone modifications such as histone acetylation and methylation have been observed in patients with PAH and are linked to vascular remodeling and pulmonary vascular dysfunction. In this review article, we provide a comprehensive overview of the role of key epigenetic targets in PAH pathogenesis, including DNA methyltransferase (DNMT), ten-eleven translocation enzymes (TET), switch-independent 3A (SIN3A), enhancer of zeste homolog 2 (EZH2), histone deacetylase (HDAC), and bromodomain-containing protein 4 (BRD4). Finally, we discuss the potential of multi-omics integration to better understand the molecular signature and profile of PAH patients and how this approach can help identify personalized treatment approaches.

MicroRNAs as Targets for Cancer Diagnosis: Interests and Limitations

MicroRNAs are small RNAs with ability to attach to the large number of RNA that regulate gene expression on post-transcriptional level via inhibition or degradation of specific mRNAs. MiRNAs in cells are the primary regulators of functions such as cell growth, differentiation, and apoptosis and considerably influence cell function. The expression levels of microRNAs change in human diseases, including cancer. These changes highlight their essential role in cancer pathogenesis. Ubiquitous irregular expression profiles of miRNAs have been detected in various human cancers using genome-wide identification techniques, which are emerging as novel diagnostic and prognostic cancer biomarkers of high specificity and sensitivity. The measurable miRNAs with enhanced stability in blood, tissues, and other body fluids provide a comprehensive source of miRNA-dependent biomarkers for human cancers. The leading role of miRNAs as potential biomarkers in human cancers is discussed in this article. In addition, the interests and difficulties of miRNAs as biomarkers have been explored.

Basic Principles of RNA Interference: Nucleic Acid Types and In Vitro Intracellular Delivery Methods

Since its discovery in 1989, RNA interference (RNAi) has become a widely used tool for the in vitro downregulation of specific gene expression in molecular biological research. This basically involves a complementary RNA that binds a target sequence to affect its transcription or translation process. Currently, various small RNAs, such as small interfering RNA (siRNA), micro RNA (miRNA), small hairpin RNA (shRNA), and PIWI interacting RNA (piRNA), are available for application on in vitro cell culture, to regulate the cells' gene expression by mimicking the endogenous RNAi-machinery. In addition, several biochemical, physical, and viral methods have been established to deliver these RNAs into the cell or nucleus. Since each RNA and each delivery method entail different off-target effects, limitations, and compatibilities, it is crucial to understand their basic mode of action. This review is intended to provide an overview of different nucleic acids and delivery methods for planning, interpreting, and troubleshooting of RNAi experiments.

Understanding the Roles and Regulation of Mitochondrial microRNAs (MitomiRs) in Neurodegenerative Diseases: Current Status and Advances

MicroRNAs (miRNA) are a class of small non-coding RNA, roughly 21 - 22 nucleotides in length, which are master gene regulators. These miRNAs bind to the mRNA's 3' - untranslated region and regulate post-transcriptional gene regulation, thereby influencing various physiological and cellular processes. Another class of miRNAs known as mitochondrial miRNA (MitomiRs) has been found to either originate from the mitochondrial genome or be translocated directly into the mitochondria. Although the role of nuclear DNA encoded miRNA in the progression of various neurological diseases such as Parkinson's disease, Alzheimer's disease, Huntington's disease, etc. is well known, accumulating evidence suggests the possible role of deregulated mitomiRs in the progression of various neurodegenerative diseases with unknown mechanism. We have attempted to outline the current state of mitomiRs role in controlling mitochondrial gene expression and function through this review, paying particular attention to their contribution to neurological processes, their etiology, and their potential therapeutic use.

A Review of IsomiRs in Colorectal Cancer

As advancements in sequencing technology rapidly continue to develop, a new classification of microRNAs has occurred with the discovery of isomiRs, which are relatively common microRNAs with sequence variations compared to their established template microRNAs. This review article seeks to compile all known information about isomiRs in colorectal cancer (CRC), which has not, to our knowledge, been gathered previously to any great extent. A brief overview is given of the history of microRNAs, their implications in colon cancer, the canonical pathway of biogenesis and isomiR classification. This is followed by a comprehensive review of the literature that is available on microRNA isoforms in CRC. The information on isomiRs presented herein shows that isomiRs hold great promise for translation into new diagnostics and therapeutics in clinical medicine.

Unleash Multifunctional Role of miRNA Biogenesis Gene Variants (XPO5*rs34324334 and RAN*rs14035) with Susceptibility to Hepatocellular Carcinoma

Numerous reports have explored the roles of different genetic variants in miRNA biogenesis mechanisms and the progression of various types of carcinomas. The goal of this study is to explore the association between XPO5*rs34324334 and RAN*rs14035 gene variants and susceptibility to hepatocellular carcinoma (HCC). In a cohort of 234 participants (107 HCC patients and 127 unrelated cancer-free controls) from the same geographic region, we characterized allelic discrimination using PCR-RFLP and performed subgroup analysis and multivariate regression. We found that the frequency of the XPO5*rs34324334 (A) variant was correlated with elevated risk of HCC under allelic (OR = 10.09, p-value < 0.001), recessive (OR = 24.1, p-value < 0.001), and dominant (OR = 10.1, p-value < 0.001) models. A/A genotype was associated with hepatitis C cirrhosis (p-value = 0.012), ascites (p-value = 0.003), and higher levels of alpha-fetoproteins (p-value = 0.011). Carriers of the RAN*rs14035 (T) variant were more likely to develop HCC under allelic (OR = 1.76, p-value = 0.003) and recessive (OR = 3.27, p-value < 0.001) models. Our results suggest that XPO5*rs34324334 and RAN*rs14035 variants are independent risk factors for developing HCC.