Exosomal miRNAs: novel players in viral infection

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.

Exosomal microRNAs in cancer metastasis: A bridge between tumor micro and macroenvironment

Malignant tumors are complicated structures of cancer cells that are constantly in communication with their local and distant environment. Exosomes are released by tumor cells and can facilitate the cell-cell interaction within the local microenvironment and the primary tumor. In fact, exosomes are secreted by both tumor and non-tumor cells, to provide a mutual communication network between cells and their micro- and/or macro-environments. Exososmes can contain a variety of biological cargos mostly based on their originated cells. Uptake of these exosomes by their recipient cells results in the alterations that their cargo can exert. MicroRNAs are identified as one of the most critical exosomal components, considering their pivotal regulatory roles in distinct biological process, including metastasis. Release and absorbance of exosomal microRNAs is possible by various cells within the host, and can have distinct biological consequences. Therefore, in this review we will discuss the role of exosomal microRNAs derived from tumor cells and untransformed cells within their micro- and macroenvironment in cancer progression and metastasis.

The Host miR-17-92 Cluster Negatively Regulates Mouse Mammary Tumor Virus (MMTV) Replication Primarily Via Cluster Member miR-92a

The mouse mammary tumor virus (MMTV) is a well-known causative agent of breast cancer in mice. Previously, we have shown that MMTV dysregulates expression of the host miR-17-92 cluster in MMTV-infected mammary glands and MMTV-induced tumors. This cluster, better known as oncomiR-1, is frequently dysregulated in cancers, particularly breast cancer. In this study, our aim was to uncover a functional interaction between MMTV and the cluster. Our results reveal that MMTV expression led to dysregulation of the cluster in both mammary epithelial HC11 and HEK293T cells with the expression of miR-92a cluster member being affected the most. Conversely, overexpression of the whole or partial cluster significantly repressed MMTV expression. Notably, overexpression of cluster member miR-92a alone repressed MMTV expression to the same extent as overexpression of the complete/partial cluster. Inhibition of miR-92a led to nearly a complete restoration of MMTV expression, while deletion/substitution of the miR-92a seed sequence rescued MMTV expression. Dual luciferase assays identified MMTV genomic RNA as the potential target of miR-92a. These results show that the miR-17-92 cluster acts as part of the cell's well-known miRNA-based anti-viral response to thwart incoming MMTV infection. Thus, this study provides the first evidence highlighting the biological significance of host miRNAs in regulating MMTV replication and potentially influencing tumorigenesis.

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.

Critical role of miR-21/exosomal miR-21 in autophagy pathway

Activation of autophagy, a process of cellular stress response, leads to the breakdown of proteins, organelles, and other parts of the cell in lysosomes, and can be linked to several ailments, such as cancer, neurological diseases, and rare hereditary syndromes. Thus, its regulation is very carefully monitored. Transcriptional and post-translational mechanisms domestically or in whole organisms utilized to control the autophagic activity, have been heavily researched. In modern times, microRNAs (miRNAs) are being considered to have a part in post-translational orchestration of the autophagic activity, with miR-21 as one of the best studied miRNAs, it is often more than expressed in cancer cells. This regulatory RNA is thought to play a major role in a plethora of processes and illnesses including growth, cancer, cardiovascular disease, and inflammation. Different studies have suggested that a few autophagy-oriented genes, such as PTEN, Rab11a, Atg12, SIPA1L2, and ATG5, are all targeted by miR-21, indicating its essential role in the regulation.

Critical role of exosome, exosomal non-coding RNAs and non-coding RNAs in head and neck cancer angiogenesis

Head and neck cancer (HNC) refers to the epithelial malignancies of the upper aerodigestive tract. HNCs have a constant yet slow-growing rate with an unsatisfactory overall survival rate globally. The development of new blood vessels from existing blood conduits is regarded as angiogenesis, which is implicated in the growth, progression, and metastasis of cancer. Aberrant angiogenesis is a known contributor to human cancer progression. Representing a promising therapeutic target, the blockade of angiogenesis aids in the reduction of the tumor cells oxygen and nutrient supplies. Despite the promise, the association of existing anti-angiogenic approaches with severe side effects, elevated cancer regrowth rates, and limited survival advantages is incontrovertible. Exosomes appear to have an essential contribution to the support of vascular proliferation, the regulation of tumor growth, tumor invasion, and metastasis, as they are a key mediator of information transfer between cells. In the exocrine region, various types of noncoding RNAs (ncRNAs) identified to be enriched and stable and contribute to the occurrence and progression of cancer. Mounting evidence suggest that exosome-derived ncRNAs are implicated in tumor angiogenesis. In this review, the characteristics of angiogenesis, particularly in HNC, and the impact of ncRNAs on HNC angiogenesis will be outlined. Besides, we aim to provide an insight on the regulatory role of exosomes and exosome-derived ncRNAs in angiogenesis in different types of HNC.

Exosomes: A Cutting-Edge Theranostics Tool for Oral Cancer

Exosomes are a subpopulation of extracellular vesicles (EVs) secreted by cells. In cancer, they are key cellular messengers during cancer development and progression. Tumor-derived exosomes (TEXs) promote cancer progression. In oral cancer, the major complication is oral squamous cell carcinoma (OSCC). Exosomes show strong participation in several OSCC-related activities such as uncontrolled cell growth, immune suppression, angiogenesis, metastasis, and drug and therapeutic resistance. It is also a potential biomarker source for oral cancer. Some therapeutic exosome sources such as stem cells, plants (it is more effective compared to others), and engineered exosomes reduce oral cancer development. This therapeutic approach is effective because of its specificity, biocompatibility, and cell-free therapy (it reduced side effects in cancer treatment). This article highlights exosome-based theranostics signatures in oral cancer, clinical trials, challenges of exosome-based oral cancer research, and future improvements. In the future, exosomes may become an effective and affordable solution for oral cancer.

Extracellular Vesicles: The Invisible Heroes and Villains of COVID-19 Central Neuropathology

Acknowledging the neurological symptoms of COVID-19 and the long-lasting neurological damage even after the epidemic ends are common, necessitating ongoing vigilance. Initial investigations suggest that extracellular vesicles (EVs), which assist in the evasion of the host's immune response and achieve immune evasion in SARS-CoV-2 systemic spreading, contribute to the virus's attack on the central nervous system (CNS). The pro-inflammatory, pro-coagulant, and immunomodulatory properties of EVs contents may directly drive neuroinflammation and cerebral thrombosis in COVID-19. Additionally, EVs have attracted attention as potential candidates for targeted therapy in COVID-19 due to their innate homing properties, low immunogenicity, and ability to cross the blood-brain barrier (BBB) freely. Mesenchymal stromal/stem cell (MSCs) secreted EVs are widely applied and evaluated in patients with COVID-19 for their therapeutic effect, considering the limited antiviral treatment. This review summarizes the involvement of EVs in COVID-19 neuropathology as carriers of SARS-CoV-2 or other pathogenic contents, as predictors of COVID-19 neuropathology by transporting brain-derived substances, and as therapeutic agents by delivering biotherapeutic substances or drugs. Understanding the diverse roles of EVs in the neuropathological aspects of COVID-19 provides a comprehensive framework for developing, treating, and preventing central neuropathology and the severe consequences associated with the disease.

Role of microRNA-146a in cancer development by regulating apoptosis

Despite great advances in diagnostic and treatment options for cancer, like chemotherapy surgery, and radiation therapy it continues to remain a major global health concern. Further research is necessary to find new biomarkers and possible treatment methods for cancer. MicroRNAs (miRNAs), tiny non-coding RNAs found naturally in the body, can influence the activity of several target genes. These genes are often disturbed in diseases like cancer, which perturbs functions like differentiation, cell division, cell cycle, apoptosis and proliferation. MiR-146a is a commonly and widely used miRNA that is often overexpressed in malignant tumors. The expression of miR-146a has been correlated with many pathological and physiological changes in cancer cells, such as the regulation of various cell death paths. It's been established that the control of cell death pathways has a huge influence on cancer progression. To improve our understanding of the interrelationship between miRNAs and cancer cell apoptosis, it's necessary to explore the impact of miRNAs through the alteration in their expression levels. Research has demonstrated that the appearance and spread of cancer can be mitigated by moderating the expression of certain miRNA - a commencement of treatment that presents a hopeful approach in managing cancer. Consequently, it is essential to explore the implications of miR-146a with respect to inducing different forms of tumor cell death, and evaluate its potential to serve as a target for improved chemotherapy outcomes. Through this review, we provide an outline of miR-146a's biogenesis and function, as well as its significant involvement in apoptosis. As well, we investigate the effects of exosomal miR-146a on the promotion of apoptosis in cancer cells and look into how it could possibly help combat chemotherapeutic resistance.

MicroRNAs: Small but Key Players in Viral Infections and Immune Responses to Viral Pathogens

Since the discovery of microRNAs (miRNAs) in C. elegans in 1993, the field of miRNA research has grown steeply. These single-stranded non-coding RNA molecules canonically work at the post-transcriptional phase to regulate protein expression. miRNAs are known to regulate viral infection and the ensuing host immune response. Evolving research suggests miRNAs are assets in the discovery and investigation of therapeutics and diagnostics. In this review, we succinctly summarize the latest findings in (i) mechanisms underpinning miRNA regulation of viral infection, (ii) miRNA regulation of host immune response to viral pathogens, (iii) miRNA-based diagnostics and therapeutics targeting viral pathogens and challenges, and (iv) miRNA patents and the market landscape. Our findings show the differential expression of miRNA may serve as a prognostic biomarker for viral infections in regard to predicting the severity or adverse health effects associated with viral diseases. While there is huge market potential for miRNA technology, the novel approach of using miRNA mimics to enhance antiviral activity or antagonists to inhibit pro-viral miRNAs has been an ongoing research endeavor. Significant hurdles remain in terms of miRNA delivery, stability, efficacy, safety/tolerability, and specificity. Addressing these challenges may pave a path for harnessing the full potential of miRNAs in modern medicine.

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

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

Viral miRNA regulation of host gene expression

Viruses have evolved a multitude of mechanisms to combat barriers to productive infection in the host cell. Virally-encoded miRNAs are one such means to regulate host gene expression in ways that benefit the virus lifecycle. miRNAs are small non-coding RNAs that regulate protein expression but do not trigger the adaptive immune response, making them powerful tools encoded by viruses to regulate cellular processes. Diverse viruses encode for miRNAs but little sequence homology exists between miRNAs of different viral species. Despite this, common cellular pathways are targeted for regulation, including apoptosis, immune evasion, cell growth and differentiation. Herein we will highlight the viruses that encode miRNAs and provide mechanistic insight into how viral miRNAs aid in lytic and latent infection by targeting common cellular processes. We also highlight how viral miRNAs can mimic host cell miRNAs as well as how viral miRNAs have evolved to regulate host miRNA expression. These studies dispel the myth that viral miRNAs are subtle regulators of gene expression, and highlight the critical importance of viral miRNAs to the virus lifecycle.

New Potential MicroRNA Biomarkers in Human Immunodeficiency Virus Elite Controllers, Human Immunodeficiency Virus Infections, and Coinfections with Hepatitis B Virus or Hepatitis C Virus

INTRODUCTION

This research aimed to evaluate the specific microRNA (miRNA) including miR-17-5p, miRN-140-3p miR-191-5p, miR-200c-3p, and miR-N367 and cellular factors (p21, SDF-1, XCL1, CCL-2, and IL-2) in controlling replication of human immunodeficiency virus (HIV) in ECs.

METHODS

The expression of miRNAs was assessed between healthy control groups and patient groups including ART-naïve HIV, HIV ART, ECs, and coinfection (HIV-HBV and HIV-HCV) via real-time PCR technique. Besides, the expression level of the nef gene and cellular factors were assessed by the ELISA method. The differences in the level of cellular factors and selected miRNAs between study groups were analyzed using the Kruskal-Wallis H or one-way ANOVA test. In addition, the potential of selected miRNAs as biomarkers for discriminating study groups was assessed by the receiver-operator characteristic (ROC) curve analysis.

RESULTS

Some miRNAs in ECs, HIV ART, and healthy controls have similar expression patterns, whereas a miRNA expression profile of patient groups significantly differed compared to EC and control groups. According to ROC curve analyses, the miR-17-5p, miR-140-3p miR-191-5p, miR-200c-3p, and miR-N367 can be served as biomarkers for discriminating ECs from ART-naïve HIV-infected groups. There was a significant correlation between some miRNAs and cellular factors/the viral load as well.

CONCLUSION

This report demonstrated a differentiation in the expression of selected immunological factors and cellular/viral miRNAs in ECs compared to other patient groups. Some miRNAs and cellular factors are involved in the viral replication control, immune response/modulation and can be used as biomarkers for diagnosis of ECs and differentiation with other groups. Differential expression of these miRNAs and cellular factors in different stages of HIV infection can help in finding novel ways for infection control.

Virus-Derived Small RNAs and microRNAs in Health and Disease

MicroRNAs (miRNAs) are short noncoding RNAs that can regulate all steps of gene expression (induction, transcription, and translation). Several virus families, primarily double-stranded DNA viruses, encode small RNAs (sRNAs), including miRNAs. These virus-derived miRNAs (v-miRNAs) help the virus evade the host's innate and adaptive immune system and maintain an environment of chronic latent infection. In this review, the functions of the sRNA-mediated virus-host interactions are highlighted, delineating their implication in chronic stress, inflammation, immunopathology, and disease. We provide insights into the latest viral RNA-based research-in silico approaches for functional characterization of v-miRNAs and other RNA types. The latest research can assist toward the identification of therapeutic targets to combat viral infections.

The role of extracellular vesicle-derived miRNAs in adipose tissue function and metabolic health

Extracellular vesicles (EVs) are nanometer size lipid particles that are released from virtually every cell type. Recent studies have shown that miRNAs carried by EVs play important roles in intercellular and interorgan communication. In the context of obesity and insulin resistance, EV-derived miRNAs functionally bridge major metabolic organs, including the adipose tissue, skeletal muscle, liver, and pancreas, to regulate insulin secretion and signaling. As a result, many of these EV-derived miRNAs have been proposed as potential disease biomarkers and/or therapeutic agents. However, the field's knowledge of EV miRNA-mediated regulation of mammalian metabolism is still in its infancy. Here, we review the evidence indicating that EV-derived miRNAs provide cell-to-cell and organ-to-organ communication to support metabolic health, highlight the potential medical relevance of these discoveries, and discuss the most important knowledge gaps and future directions for this field.

Circulating and extracellular vesicle-derived microRNAs as biomarkers in bone-related diseases

MicroRNAs (miRNA) are small non-coding RNA molecules that regulate posttranscriptional gene expression by repressing messengerRNA-targets. MiRNAs are abundant in many cell types and are secreted into extracellular fluids, protected from degradation by packaging in extracellular vesicles. These circulating miRNAs are easily accessible, disease-specific and sensitive to small changes, which makes them ideal biomarkers for diagnostic, prognostic, predictive or monitoring purposes. Specific miRNA signatures can be reflective of disease status and development or indicators of poor treatment response. This is especially important in malignant diseases, as the ease of accessibility of circulating miRNAs circumvents the need for invasive tissue biopsy. In osteogenesis, miRNAs can act either osteo-enhancing or osteo-repressing by targeting key transcription factors and signaling pathways. This review highlights the role of circulating and extracellular vesicle-derived miRNAs as biomarkers in bone-related diseases, with a specific focus on osteoporosis and osteosarcoma. To this end, a comprehensive literature search has been performed. The first part of the review discusses the history and biology of miRNAs, followed by a description of different types of biomarkers and an update of the current knowledge of miRNAs as biomarkers in bone related diseases. Finally, limitations of miRNAs biomarker research and future perspectives will be presented.

Systemic lupus erythematosus: From non-coding RNAs to exosomal non-coding RNAs

Systemic lupus erythematosus (SLE), as an immunological illness, frequently impacts young females. Both vulnerabilities to SLE and the course of the illness's clinical symptoms have been demonstrated to be affected by individual differences in non-coding RNA expression. Many non-coding RNAs (ncRNAs) are out of whack in patients with SLE. Because of the dysregulation of several ncRNAs in peripheral blood of patients suffering from SLE, these ncRNAs to be showed valuable as biomarkers for medication response, diagnosis, and activity. NcRNAs have also been demonstrated to influence immune cell activity and apoptosis. Altogether, these facts highlight the need of investigating the roles of both families of ncRNAs in the progress of SLE. Being aware of the significance of these transcripts perhaps elucidates the molecular pathogenesis of SLE and could open up promising avenues to create tailored treatments during this condition. In this review we summarized various non-coding RNAs and Exosomal non-coding RNAs in SLE.

Exosomes from bacteria (Streptococcus parauberis) challenged olive flounder (Paralichthys olivaceus): Isolation, molecular characterization, wound healing, and regeneration activities

Exosomes are a group of extracellular vesicles carrying membrane proteins, lipids, RNAs, and, cytosolic proteins, which play key role in intercellular communication and homeostasis. This study describes the isolation, physicochemical, morphological and molecular characterization, toxicity, wound healing, and regeneration properties of plasma derived exosomes from naive (phosphate-buffered saline [PBS]-injected; PBS-Exo) and Streptococcus parauberis-challenged (Sp-Exo) olive flounder (Paralichthys olivaceus). The average diameters of PBS-Exo and Sp-Exo were 120.5 ± 6.1 and 113.1 ± 9.3 nm, respectively, and they presented unique cup shape morphologies. Both exosomes exhibited classical tetraspanin surface markers (CD81, CD9, and CD63) and were enriched with acetylcholinesterase. High-throughput miRNA profiling revealed differentially expressed miRNAs (log₂ fold change ≥1; P < 0.05), including 14 known and 22 novel miRNAs, in Sp-Exo. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that the target genes of the miRNAs contribute towards various physiological and immunological functions, including wound healing and fin regeneration. Sp-Exo exhibited a rapid wound healing (cell migration) capacity in human fibroblast cells, and its mRNA and protein expression patterns corroborated its activity. Higher larval fin regeneration was more prevalent in Sp-Exo than in PBS-Exo, which further confirmed its functional significance. Our study provides the first basic physiochemical, morphometric, molecular (miRNA profiling), and wound healing evidences of Sp-Exo in olive flounder and highlights important miRNA cargoes in exosomes that may be potential therapeutic candidates in wound healing.

Exosomal MicroRNA Profiling

Exosomes are extracellular vesicles, which have the ability to convey various types of cargo between cells. Lately, a great amount of interest has been paid to exosomal microRNAs (miRNAs), since much evidence has suggested that the sorting of miRNAs into exosomes is not an accidental process. It has been shown that exosomal miRNAs (exo-miRNAs) are implicated in a variety of cellular processes including (but not limited to) cell migration, apoptosis, proliferation, and autophagy. Exosomes can play a role in cardiovascular diseases and can be used as diagnostic biomarkers for several diseases, especially cancer. Tremendous advances in technology have led to the development of various platforms for miRNA profiling. Each platform has its own limitations and strengths that need to be understood in order to use them properly. In the current review, we summarize some exo-miRNAs that are relevant to exo-miRNA profiling studies and describe new methods used for the measurement of miRNA profiles in different human bodily fluids.

Updated review of advances in microRNAs and complex diseases: experimental results, databases, webservers and data fusion

MicroRNAs (miRNAs) are gene regulators involved in the pathogenesis of complex diseases such as cancers, and thus serve as potential diagnostic markers and therapeutic targets. The prerequisite for designing effective miRNA therapies is accurate discovery of miRNA-disease associations (MDAs), which has attracted substantial research interests during the last 15 years, as reflected by more than 55 000 related entries available on PubMed. Abundant experimental data gathered from the wealth of literature could effectively support the development of computational models for predicting novel associations. In 2017, Chen et al. published the first-ever comprehensive review on MDA prediction, presenting various relevant databases, 20 representative computational models, and suggestions for building more powerful ones. In the current review, as the continuation of the previous study, we revisit miRNA biogenesis, detection techniques and functions; summarize recent experimental findings related to common miRNA-associated diseases; introduce recent updates of miRNA-relevant databases and novel database releases since 2017, present mainstream webservers and new webserver releases since 2017 and finally elaborate on how fusion of diverse data sources has contributed to accurate MDA prediction.

Extracellular Vesicles in Veterinary Medicine

Extracellular vesicles (EVs) are cell-derived membrane-bound vesicles involved in many physiological and pathological processes not only in humans but also in all the organisms of the eukaryotic and prokaryotic kingdoms. EV shedding constitutes a fundamental universal mechanism of intra-kingdom and inter-kingdom intercellular communication. A tremendous increase of interest in EVs has therefore grown in the last decades, mainly in humans, but progressively also in animals, parasites, and bacteria. With the present review, we aim to summarize the current status of the EV research on domestic and wild animals, analyzing the content of scientific literature, including approximately 220 papers published between 1984 and 2021. Critical aspects evidenced through the veterinarian EV literature are discussed. Then, specific subsections describe details regarding EVs in physiology and pathophysiology, as biomarkers, and in therapy and vaccines. Further, the wide area of research related to animal milk-derived EVs is also presented in brief. The numerous studies on EVs related to parasites and parasitic diseases are excluded, deserving further specific attention. The literature shows that EVs are becoming increasingly addressed in veterinary studies and standardization in protocols and procedures is mandatory, as in human research, to maximize the knowledge and the possibility to exploit these naturally produced nanoparticles.

Non-Coding RNAs and Oral Cancer: Small Molecules With Big Functions

Oral cancer remains a major public concern with considerable socioeconomic impact in the world. Despite substantial advancements have been made in treating oral cancer, the five-year survival rate for oral cancer remained undesirable, and the molecular mechanisms underlying OSCC carcinogenesis have not been fully understood. Noncoding RNAs (ncRNAs) include transfer RNAs (tRNAs), as well as small RNAs such as microRNAs, and the long ncRNAs such as HOTAIR are a large segment of the transcriptome that do not have apparent protein-coding roles, but they have been verified to play important roles in diverse biological processes, including cancer cell development. Cell death, such as apoptosis, necrosis, and autophagy, plays a vital role in the progression of cancer. A better understanding of the regulatory relationships between ncRNAs and these various types of cancer cell death is therefore urgently required. The occurrence and development of oral cancer can be controlled by increasing or decreasing the expression of ncRNAs, a method which confers broad prospects for oral cancer treatment. Therefore, it is urgent for us to understand the influence of ncRNAs on the development of different modes of oral tumor death, and to evaluate whether ncRNAs have the potential to be used as biological targets for inducing cell death and recurrence of chemotherapy. The purpose of this review is to describe the impact of ncRNAs on cell apoptosis and autophagy in oral cancer in order to explore potential targets for oral cancer therapy.

MiR-1290: a potential therapeutic target for regenerative medicine or diagnosis and treatment of non-malignant diseases

MicroRNAs are a set of small non-coding RNAs that could change gene expression with post-transcriptional regulation. MiRNAs have a significant role in regulating molecular signaling pathways and innate and adaptive immune system activity. Moreover, miRNAs can be utilized as a powerful instrument for tissue engineers and regenerative medicine by altering the expression of genes and growth factors. MiR-1290, which was first discovered in human embryonic stem cells, is one of those miRNAs that play an essential role in developing the fetal nervous system. This review aims to discuss current findings on miR-1290 in different human pathologies and determine whether manipulation of miR-1290 could be considered a possible therapeutic strategy to treat different non-malignant diseases. The results of these studies suggest that the regulation of miR-1290 may be helpful in the treatment of some bacterial (leprosy) and viral infections (HIV, influenza A, and Borna disease virus). Also, adjusting the expression of miR-1290 in non-infectious diseases such as celiac disease, necrotizing enterocolitis, polycystic ovary syndrome, pulmonary fibrosis, ankylosing spondylitis, muscle atrophy, sarcopenia, and ischemic heart disease can help to treat these diseases better. In addition to acting as a biomarker for the diagnosis of non-malignant diseases (such as NAFLD, fetal growth, preeclampsia, down syndrome, chronic rhinosinusitis, and oral lichen planus), the miR-1290 can also be used as a valuable instrument in tissue engineering and reconstructive medicine. Consequently, it is suggested that the regulation of miR-1290 could be considered a possible therapeutic target in the treatment of non-malignant diseases in the future.

Advances in exosome biomarkers for cervical cancer

Cervical cancer (CC) ranks as the fourth most frequently diagnosed malignancy in females worldwide. Exosomes are a subclass of extracellular vesicles released by nearly all types of cells that act as cargo transport vehicles, carrying proteins, and genetic material (such as miRNAs, long noncoding RNAs, and mRNAs) derived from their parent cells may affect receiving cells and thus have emerged as key players in several biological processes, including inflammatory pathways. In this review, we concentrated on the findings of exosome investigations in CC, particularly their components. They direct the actions of CC cells by inducing surface molecules associated with various biological pathways. We summarized the current knowledge of exosomal RNAs and proteins from CC cells and discussed the feasibility of exosomes as potential biomarkers for CC. We suggest that cancer-derived exosomes promote metastasis in CC by supporting EMT, controlling the proliferation, invasion, or migration of cancer cells, as well as influencing immune escape and aiding angiogenesis. Overall, cancer-derived exosomes are critical in the progression of CC, and further studies are necessary to advance our understanding of the clinical value of exosomes in CC.

Circulating Abnormal Extracellular Vesicles: Their Mechanism for Crossing Blood-Brain Barrier, Effects on Central Nervous System and Detection Methods

Central nervous system (CNS) diseases are difficult to treat and harmful. Many CNS diseases are secondary to peripheral diseases, such as tumor brain metastases (BMS), viral infections and inflammation of the brain, and their pathogenic factors travel through the circulatory system to the brain, eventually leading to lesions. Extracellular vesicles (EVs) play an important role in this process. Recent studies have shown that, extracellular EVs can effectively cross the blood- brain barrier (BBB) through endocytosis and they transmit molecular signals in cell-to-cell communication. Abnormal EVs produced in the lesion portion transport pathogenic factors, including miRNAs, proteins, and virions into the CNS. These pathogenic factors participate in cellular pathways to interfere with homeostasis or are themselves pathogens that directly damage CNS. In addition, different or specific pathological molecules in EVs are potential disease markers. We herein reviewed pathways through which the abnormal EVs cross BBB and adverse effects of abnormal exosomes. We also and summarized their existing detection techniques, so as to provide basis for prevention and early diagnosis of secondary diseases.

MicroRNA let-7 and viral infections: focus on mechanisms of action

MicroRNAs (miRNAs) are fundamental post-transcriptional modulators of several critical cellular processes, a number of which are involved in host defense mechanisms. In particular, miRNA let-7 functions as an essential regulator of the function and differentiation of both innate and adaptive immune cells. Let-7 is involved in several human diseases, including cancer and viral infections. Several viral infections have found ways to dysregulate the expression of miRNAs. Extracellular vesicles (EV) are membrane-bound lipid structures released from many types of human cells that can transport proteins, lipids, mRNAs, and miRNAs, including let-7. After their release, EVs are taken up by the recipient cells and their contents released into the cytoplasm. Let-7-loaded EVs have been suggested to affect cellular pathways and biological targets in the recipient cells, and can modulate viral replication, the host antiviral response, and the action of cancer-related viruses. In the present review, we summarize the available knowledge concerning the expression of let-7 family members, functions, target genes, and mechanistic involvement in viral pathogenesis and host defense. This may provide insight into the development of new therapeutic strategies to manage viral infections.

Survival‑related DLEU1 is associated with HPV infection status and serves as a biomarker in HPV‑infected cervical cancer

Human papillomavirus (HPV) is the most common risk factor for the occurrence of cervical cancer (CC). In recent years, the important roles of long non‑coding RNAs (lncRNAs) in CC have emerged, but studies on the relationship between lncRNAs and HPV‑positive (HPV+) CC remain scarce. The present study aimed to investigate whether lncRNA deleted in lymphocytic leukemia 1 (DLEU1) is associated with HPV infection and explore the clinical significance of DLEU1 in HPV+ patients with CC. DLEU1 expression was detected by reverse transcription‑quantitative PCR. The ability of DLEU1 to screen patients with CC from controls and differentiate individuals with different HPV infection status was evaluated by receiver operating characteristic analysis. The association of DLEU1 with the survival prognosis of patients with CC was assessed by Kaplan‑Meier survival analysis and Cox regression analysis. The RNA Interactome Database was used to predict molecules interacting with DLEU1. The results indicated that DLEU1 expression was significantly upregulated in CC tissues and cell lines, particularly in those that were HPV+. In addition, DLEU1 had a high diagnostic value in discriminating patients with CC and differentiating between HPV+ and HPV‑ patients with CC, and had a certain ability to screen HPV+ controls. DLEU1 was correlated with HPV infection in CC patients. Furthermore, DLEU1 was indicated to be associated with survival prognosis in both total patients with CC and HPV+ patients with CC, and independently predict the prognosis of patients with CC. Most of the molecules interacting with DLEU1 were microRNAs. In conclusion, abnormal DLEU1 expression is associated with HPV infection and may serve as a diagnostic and prognostic biomarker for HPV+ patients with CC.

MicroRNAs and exosomes: Cardiac stem cells in heart diseases

Treating cardiovascular diseases with cardiac stem cells (CSCs) is a valid treatment among various stem cell-based therapies. With supplying the physiological need for cardiovascular cells as their main function, under pathological circumstances, CSCs can also reproduce the myocardial cells. Although studies have identified many of CSCs' functions, our knowledge of molecular pathways that regulate these functions is not complete enough. Either physiological or pathological studies have shown, stem cells proliferation and differentiation could be regulated by microRNAs (miRNAs). How miRNAs regulate CSC behavior is an interesting area of research that can help us study and control the function of these cells in vitro; an achievement that may be beneficial for patients with cardiovascular diseases. The secretome of stem and progenitor cells has been studied and it has been determined that exosomes are the main source of their secretion which are very small vesicles at the nanoscale and originate from endosomes, which are secreted into the extracellular space and act as key signaling organelles in intercellular communication. Mesenchymal stem cells, cardiac-derived progenitor cells, embryonic stem cells, induced pluripotent stem cells (iPSCs), and iPSC-derived cardiomyocytes release exosomes that have been shown to have cardioprotective, immunomodulatory, and reparative effects. Herein, we summarize the regulation roles of miRNAs and exosomes in cardiac stem cells.

Advances in Biosensors Technology for Detection and Characterization of Extracellular Vesicles

Exosomes are extracellular vehicles (EVs) that encapsulate genomic and proteomic material from the cell of origin that can be used as biomarkers for non-invasive disease diagnostics in point of care settings. The efficient and accurate detection, quantification, and molecular profiling of exosomes are crucial for the accurate identification of disease biomarkers. Conventional isolation methods, while well-established, provide the co-purification of proteins and other types of EVs. Exosome purification, characterization, and OMICS analysis are performed separately, which increases the complexity, duration, and cost of the process. Due to these constraints, the point-of-care and personalized analysis of exosomes are limited in clinical settings. Lab-on-a-chip biosensing has enabled the integration of isolation and characterization processes in a single platform. The presented review discusses recent advancements in biosensing technology for the separation and detection of exosomes. Fluorescent, colorimetric, electrochemical, magnetic, and surface plasmon resonance technologies have been developed for the quantification of exosomes in biological fluids. Size-exclusion filtration, immunoaffinity, electroactive, and acoustic-fluid-based technologies were successfully applied for the on-chip isolation of exosomes. The advancement of biosensing technology for the detection of exosomes provides better sensitivity and a reduced signal-to-noise ratio. The key challenge for the integration of clinical settings remains the lack of capabilities for on-chip genomic and proteomic analysis.

The potential use of microRNAs as a therapeutic strategy for SARS-CoV-2 infection

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, there is no effective therapeutic approach for treating SARS-CoV-2 infections. MicroRNAs (miRNAs) have been recognized to target the viral genome directly or indirectly, thereby inhibiting viral replication. Several studies have demonstrated that host miRNAs target different sites in SARS-CoV-2 RNA and constrain the production of essential viral proteins. Furthermore, miRNAs have lower toxicity, are more immunogenic, and are more diverse than protein-based and even plasmid-DNA-based therapeutic agents. In this review, we emphasize the role of miRNAs in viral infection and their potential use as therapeutic agents against COVID-19 disease. The potential of novel miRNA delivery strategies, especially EDV™ nanocells, for targeting lung tissue for treatment of SARS-CoV-2 infection is also discussed.

A comprehensive review of online resources for microRNA-diseases associations: the state of the art

MicroRNAs (miRNAs) as small 19- to 24-nucleotide noncoding RNAs regulate several mRNA targets and signaling pathways. Therefore, miRNAs are considered key regulators in cellular pathways as well as various pathologies. There is substantial interest in the relationship between disease and miRNAs, which made that one of the important research topics. Interestingly, miRNAs emerged as an attractive approach for clinical application, not only as biomarkers for diagnosis and prognosis or in the prediction of therapy response but also as therapeutic tools. For these purposes, the identification of crucial miRNAs in disease is very important. Databases provided valuable experimental and computational miRNAs-disease information in an accessible and comprehensive manner, such as miRNA target genes, miRNA related in signaling pathways and miRNA involvement in various diseases. In this review, we summarized miRNAs-disease databases in two main categories based on the general or specific diseases. In these databases, researchers could search diseases to identify critical miRNAs and developed that for clinical applications. In another way, by searching particular miRNAs, they could recognize in which disease these miRNAs would be dysregulated. Despite the significant development that has been done in these databases, there are still some limitations, such as not being updated and not providing uniform and detailed information that should be resolved in future databases. This survey can be helpful as a comprehensive reference for choosing a suitable database by researchers and as a guideline for comparing the features and limitations of the database by developer or designer. Short abstract We summarized miRNAs-disease databases that researchers could search disease to identify critical miRNAs and developed that for clinical applications. This survey can help choose a suitable database for researchers.

Exosomal miR-224 contributes to hemolymph microbiota homeostasis during bacterial infection in crustacean

It is well known that exosomes could serve as anti-microbial immune factors in animals. However, despite growing evidences have shown that the homeostasis of the hemolymph microbiota was vital for immune regulation in crustaceans, the relationship between exosomes and hemolymph microbiota homeostasis during pathogenic bacteria infection has not been addressed. Here, we reported that exosomes released from Vibrio parahaemolyticus-infected mud crabs (Scylla paramamosain) could help to maintain the homeostasis of hemolymph microbiota and have a protective effect on the mortality of the host during the infection process. We further confirmed that miR-224 was densely packaged in these exosomes, resulting in the suppression of HSP70 and disruption of the HSP70-TRAF6 complex, then the released TRAF6 further interacted with Ecsit to regulate the production of mitochondrial ROS (mROS) and the expression of Anti-lipopolysaccharide factors (ALFs) in recipient hemocytes, which eventually affected hemolymph microbiota homeostasis in response to the pathogenic bacteria infection in mud crab. To the best of our knowledge, this is the first document that reports the role of exosome in the hemolymph microbiota homeostasis modulation during pathogen infection, which reveals the crosstalk between exosomal miRNAs and innate immune response in crustaceans.

Exosomes are small membrane vesicles of endocytic origin which are widely involved in the regulation of a variety of pathological processes in mammals. Yet, although the antibacterial function of exosomes has been discovered for many years, the relationship between exosomes and hemolymph microbiota homeostasis remains unknown. In the present study, we identified the miRNAs packaged by exosomes that were possibly involved in Vibrio parahaemolyticus infection by modulating hemolymph microbiota homeostasis in crustacean mud crab Scylla paramamosain. Moreover, it was found that miR-224 was densely packaged in exosomes after Vibrio parahaemolyticus challenge, resulting in the suppression of HSP70 and disruption of the HSP70-TRAF6 complex in recipient hemocytes, then the released TRAF6 was further interacted with Ecsit to regulate ROS and ALFs levels, which eventually affected hemolymph microbiota homeostasis to cope with pathogenic bacteria infection. Our finding is the first to reveal the relationship between exosomes and hemolymph microbiota homeostasis in animals, which shows a novel molecular mechanism of invertebrate resistance to pathogenic microbial infection.

Oncogenic viruses and chemoresistance: What do we know?

Chemoresistance is often referred to as a major leading reason for cancer therapy failure, causing cancer relapse and further metastasis. As a result, an urgent need has been raised to reach a full comprehension of chemoresistance-associated molecular pathways, thereby designing new therapy methods. Many of metastatic tumor masses are found to be related with a viral cause. Although combined therapy is perceived as the model role therapy in such cases, chemoresistant features, which is more common in viral carcinogenesis, often get into way of this kind of therapy, minimizing the chance of survival. Some investigations indicate that the infecting virus dominates other leading factors, i.e., genetic alternations and tumor microenvironment, in development of cancer cell chemoresistance. Herein, we have gathered the available evidence on the mechanisms under which oncogenic viruses cause drug-resistance in chemotherapy.

Plant-derived exosomal microRNAs inhibit lung inflammation induced by exosomes SARS-CoV-2 Nsp12

Lung inflammation is a hallmark of coronavirus disease 2019 (COVID-19). In this study, we show that mice develop inflamed lung tissue after being administered exosomes released from the lung epithelial cells exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Nsp12 and Nsp13 (exosomes^Nsp12Nsp13). Mechanistically, we show that exosomes^Nsp12Nsp13 are taken up by lung macrophages, leading to activation of nuclear factor κB (NF-κB) and the subsequent induction of an array of inflammatory cytokines. Induction of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β from exosomes^Nsp12Nsp13-activated lung macrophages contributes to inducing apoptosis in lung epithelial cells. Induction of exosomes^Nsp12Nsp13-mediated lung inflammation was abolished with ginger exosome-like nanoparticle (GELN) microRNA (miRNA aly-miR396a-5p. The role of GELNs in inhibition of the SARS-CoV-2-induced cytopathic effect (CPE) was further demonstrated via GELN aly-miR396a-5p- and rlcv-miR-rL1-28-3p-mediated inhibition of expression of Nsp12 and spike genes, respectively. Taken together, our results reveal exosomes^Nsp12Nsp13 as potentially important contributors to the development of lung inflammation, and GELNs are a potential therapeutic agent to treat COVID-19.

Cervical Cancer Diagnosis: Insights into Biochemical Biomarkers and Imaging Techniques

Cervical malignancy is known as one of the important cancers which is originated from cervix. This malignancy has been observed in women infected with papillomavirus who had regular oral contraceptives, multiple pregnancies, and sexual relations. Early and fast cervical cancer diagnosis is known as two important aspects of cervical cancer therapy. Several investigations indicated that early and fast detection of cervical cancer could be associated with better treatment process and increasing survival rate of patients with this malignancy. Imaging techniques are very important diagnosis tools that could be employed for diagnosis and following responses to therapy in various cervical cancer stages. Multiple lines of evidence indicated that utilization of imaging techniques is related to some limitations (i.e. high cost, and invasive effects). Hence, it seems that along with using imaging techniques, finding and developing new biomarkers could be useful in the diagnosis and treatment of subjects with cervical cancer. Taken together, many studies showed that a variety of biomarkers including, several proteins, mRNAs, microRNAs, exosomes and polymorphisms might be introduced as prognostic, diagnostic and therapeutic biomarkers in cervical cancer therapy. In this review article, we highlighted imaging techniques as well as novel biomarkers for the diagnosis of cervical cancer.

Vitamin D and Non-coding RNAs: New Insights into the Regulation of Breast Cancer

Breast cancer, a life-threatening serious disease with a high incident rate among women, is responsible for thousands of cancer-associated death worldwide. Numerous investigations have evaluated the possible mechanisms related to this malignancy. Among them, non-coding RNAs (ncRNAs), i.e., microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs have recently attracted attention of researchers. In addition to recent studies for evaluating the role of ncRNAs in breast cancer etiology, some investigations have revealed that vitamin D has regulatory and therapeutic roles in breast cancer. Moreover, an important link between vitamin D and ncRNAs in cancer therapy has been highlighted. Herein, the aim of this study was to discuss the available data on the mentioned link in breast cancer.

The emerging role of exosomal miRNAs as a diagnostic and therapeutic biomarker in Mycobacterium tuberculosis infection

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), has been the world's driving fatal bacterial contagious disease globally. It continues a public health emergency, and around one-third of the global community has been affected by latent TB infection (LTBI). This is mostly due to the difficulty in diagnosing and treating patients with TB and LTBI. Exosomes are nanovesicles (40-100 nm) released from different cell types, containing proteins, lipids, mRNA, and miRNA, and they allow the transfer of one's cargo to other cells. The functional and diagnostic potential of exosomal miRNAs has been demonstrated in bacterial infections, including TB. Besides, it has been recognized that cells infected by intracellular pathogens such as Mtb can be secreting an exosome, which is implicated in the infection's fate. Exosomes, therefore, open a unique viewpoint on the investigative process of TB pathogenicity. This study explores the possible function of exosomal miRNAs as a diagnostic biomarker. Moreover, we include the latest data on the pathogenic and therapeutic role of exosomal miRNAs in TB.

Umbilical Cord Blood-Derived Exosomes From Very Preterm Infants With Bronchopulmonary Dysplasia Impaired Endothelial Angiogenesis: Roles of Exosomal MicroRNAs

Premature infants have a high risk of bronchopulmonary dysplasia (BPD), which is characterized by abnormal development of alveoli and pulmonary vessels. Exosomes and exosomal miRNAs (EXO-miRNAs) from bronchoalveolar lavage fluid are involved in the development of BPD and might serve as predictive biomarkers for BPD. However, the roles of exosomes and EXO-miRNAs from umbilical cord blood of BPD infants in regulating angiogenesis are yet to be elucidated. In this study, we showed that umbilical cord blood-derived exosomes from BPD infants impaired angiogenesis in vitro. Next-generation sequencing of EXO-miRNAs from preterm infants without (NBPD group) or with BPD (BPD group) uncovered a total of 418 differentially expressed (DE) EXO-miRNAs. These DE EXO-miRNAs were primarily enriched in cellular function-associated pathways including the PI3K/Akt and angiogenesis-related signaling pathways. Among those EXO-miRNAs which are associated with PI3K/Akt and angiogenesis-related signaling pathways, BPD reduced the expression of hsa-miR-103a-3p and hsa-miR-185-5p exhibiting the most significant reduction (14.3% and 23.1% of NBPD group, respectively); BPD increased hsa-miR-200a-3p expression by 2.64 folds of the NBPD group. Furthermore, overexpression of hsa-miR-103a-3p and hsa-miR-185-5p in normal human umbilical vein endothelial cells (HUVECs) significantly enhanced endothelial cell proliferation, tube formation, and cell migration, whereas overexpressing hsa-miR-200a-3p inhibited these cellular responses. This study demonstrates that exosomes derived from umbilical cord blood of BPD infants impair angiogenesis, possibly via DE EXO-miRNAs, which might contribute to the development of BPD.

Cell death pathways and viruses: Role of microRNAs

Viral infections lead to the death of more than a million people each year around the world, both directly and indirectly. Viruses interfere with many cell functions, particularly critical pathways for cell death, by affecting various intracellular mediators. MicroRNAs (miRNAs) are a major example of these mediators because they are involved in many (if not most) cellular mechanisms. Virus-regulated miRNAs have been implicated in three cell death pathways, namely, apoptosis, autophagy, and anoikis. Several molecules (e.g., BECN1 and B cell lymphoma 2 [BCL2] family members) are involved in both apoptosis and autophagy, while activation of anoikis leads to cell death similar to apoptosis. These mechanistic similarities suggest that common regulators, including some miRNAs (e.g., miR-21 and miR-192), are involved in different cell death pathways. Because the balance between cell proliferation and cell death is pivotal to the homeostasis of the human body, miRNAs that regulate cell death pathways have drawn much attention from researchers. miR-21 is regulated by several viruses and can affect both apoptosis and anoikis via modulating various targets, such as PDCD4, PTEN, interleukin (IL)-12, Maspin, and Fas-L. miR-34 can be downregulated by viral infection and has different effects on apoptosis, depending on the type of virus and/or host cell. The present review summarizes the existing knowledge on virus-regulated miRNAs involved in the modulation of cell death pathways. Understanding the mechanisms for virus-mediated regulation of cell death pathways could provide valuable information to improve the diagnosis and treatment of many viral diseases.

Chitosan-Based Nanoparticles Against Viral Infections

Viral infections, in addition to damaging host cells, can compromise the host immune system, leading to frequent relapse or long-term persistence. Viruses have the capacity to destroy the host cell while liberating their own RNA or DNA in order to replicate within additional host cells. The viral life cycle makes it challenging to develop anti-viral drugs. Nanotechnology-based approaches have been suggested to deal effectively with viral diseases, and overcome some limitations of anti-viral drugs. Nanotechnology has enabled scientists to overcome the challenges of solubility and toxicity of anti-viral drugs, and can enhance their selectivity towards viruses and virally infected cells, while preserving healthy host cells. Chitosan is a naturally occurring polymer that has been used to construct nanoparticles (NPs), which are biocompatible, biodegradable, less toxic, easy to prepare, and can function as effective drug delivery systems (DDSs). Furthermore, chitosan is Generally Recognized as Safe (GRAS) by the US Food and Drug Administration (U.S. FDA). Chitosan NPs have been used in drug delivery by the oral, ocular, pulmonary, nasal, mucosal, buccal, or vaginal routes. They have also been studied for gene delivery, vaccine delivery, and advanced cancer therapy. Multiple lines of evidence suggest that chitosan NPs could be used as new therapeutic tools against viral infections. In this review we summarize reports concerning the therapeutic potential of chitosan NPs against various viral infections.

CTCF-silenced miR-137 contributes to EMT and radioresistance in esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is one of the most malignant tumors in gastrointestinal system. MicroRNAs (miRNAs) have been reported to be implicated in cancer development. However, the role of miR-137 has not been fully revealed in ESCC.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses were separately used to examine RNA level and protein level. 5-ethynyl-2'-deoxyuridine (EdU) assay, transwell assays and flow cytometry analyses were conducted to assess biological behaviors of ESCC cells. Additionally, the interaction between genes were analyzed via Chromatin Immunoprecipitation (ChIP) assay, RNA Binding Protein Immunoprecipitation (RIP) assay, RNA pull down assay and luciferase reporter assay.

RESULTS

MiR-137 was down-regulated in ESCC cells. Upregulation of miR-137 hindered ESCC cell proliferation, migration, invasion and epithelial mesenchymal transition (EMT). Besides, miR-137 enhanced the sensitivity of ESCC cells to irradiation. Moreover, CCCTC-binding factor (CTCF) inactivated miR-137 transcription in ESCC cells. Furthermore, we revealed enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) and paxillin (PXN) as the downstream targets of miR-137. In turn, EZH2 was recruited by CTCF and induced methylation in miR-137 promoter.

CONCLUSION

CTCF/Suz12/EZH2 complex-silenced miR-137 facilitates ESCC progression and radioresistance by targeting EZH2 and PXN.

Assessment of Human Papillomavirus Infection and Risk Factors in Egyptian Women With Breast Cancer

Numerous risk factors for breast cancer (BC) have been identified. High-risk human papilloma virus (HR-HPV) is the etiological agent of cervical cancer and in some cases of head and neck cancer, specifically oropharyngeal cancer, but the role of HR-HPV in evoking neoplasia in BC is still unclear. In this study, all women above the age of 18 visiting the oncology clinic at Al-Azhar university hospital and Ain Shams specialized hospital between the period of February 2017 and March 2018 were invited to participate. We determined the prevalence of HR-HPV genotypes 16, 18, and 31 in breast tissue samples from 72 women with treatment-naïve BC and 15 women with benign breast lesions (BBL) by quantitative real-time PCR (qRT-PCR) and primer sets targeting the E6 and E7 regions. High-risk human papilloma virus DNA was detected in 16 of 72 (22.2%) BC cases (viral load range = 0.3-237.8 copies/uL) and 0 of 15 women with BBL. High-risk human papilloma virus was detected in 14 of 16 (87.5%), 2 of 16 (12.5%), and 0 of 16 (0%) for genotypes 16, 18, and 31, respectively. Forty-three age-matched healthy Egyptian women were enrolled as controls for assessment of local risk factors that can be used to initiate a strategy of BC prevention in Egypt. Assessment of the risk factors demonstrated that low education level, passive smoking, lack of physical activity, family history of cancer, and use of oral contraception were significant risk factors for BC. In conclusion, our results lead us to postulate that HR-HPV infection may be implicated in the development of some types of BC in Egyptian women. In addition, identification of local risk factors can support practical prevention strategies for BC in Egypt.

The Emerging Role of Exosomes in Oral Squamous Cell Carcinoma

Oral cancer constitutes approximately 2% of all cancers, while the most common type, oral squamous cell carcinoma (OSCC) represents 90% of oral cancers. Although the treatment of OSCC has improved recently, it still has a high rate of local recurrence and poor prognosis, with a 5-year survival rate of only 50%. Advanced stage OSCC tends to metastasize to lymph nodes. Thus, exploring new therapeutic strategies for OSCC is therefore an urgent priority. Exosomes, the small membrane vesicles derived from endosomes, have been detected in a wide array of bodily fluids. Exosomes contain a diversity of proteins, mRNAs, and non-coding RNAs, including microRNAs, long non-coding RNAs, piRNAs, circular RNAs, tsRNAs, and ribosomal RNAs, which are delivered to neighboring cells or even transported to distant sites. Exosomes have been associated with the tumorigenesis of OSCC, promote the proliferation, colonization, and metastasis of OSCC by transferring their contents to the target cells. Furthermore, exosomes are involved in the regulation of the tumor microenvironment to transform conditions favoring cancer progression in vivo. In this review, we summarize the crucial role of exosomes in the tumorigenesis and progression of OSCC and discuss the potential clinical application of exosomes in OSCC treatment.

Effect of gingival mesenchymal stem cell-derived exosomes on inflammatory macrophages in a high-lipid microenvironment

OBJECTIVE

The aim of this study was to examine the effect of gingival mesenchymal stem cells derived exosomes (GMSC-Exos) on lipopolysaccharide/interferon-gamma (LPS/INF-γ)-induced inflammatory macrophages in a high-lipid microenvironment.

MATERIALS AND METHODS

Exosomes were obtained by culturing gingival mesenchymal stem cells (GMSCs) in alpha-MEM with exosome-free fetal bovine serum for 48 h. The control group was produced in vitro by inducing human acute monocytic leukemia cells (THP-1 cells) into naïve macrophages (M0). Inflammatory macrophages (M1) were made by activating M0 macrophages with LPS/IFN-γ. These M1 macrophages were treated with oxidized low-density lipoprotein (ox-LDL) to create the high-lipid group, of which some macrophages were further treated with GMSC-Exos for 24 h to form the GMSC-Exos group. Supernatants were collected, and total RNA were extracted for downstream analysis. The expression of surface markers in macrophages were analyzed by flow cytometry. The lipid accumulation level was assessed by oil red O staining.

RESULTS

Exosomes were successfully isolated from GMSC medium. The GMSC-Exos group showed lower Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β (IL-1β), and cluster of differentiation 86 (CD86) expression levels than the high-lipid group, and the highest levels of Interleukin-10 (IL-10) among all groups. The GMSC-Exos group showed significant reductions in TNF-α levels than the high-lipid group, and significant escalations in IL-10 levels than the other two groups. Oil red o Staining showed that lipid accumulation in macrophages was inhibited in the GMSC-Exos group.

CONCLUSIONS

GMSC-Exos reduce the release level and expression of inflammatory factors, inhibit lipid accumulation, and promote the polarization of pro-inflammatory macrophages into anti-inflammatory phenotype in a high-lipid microenvironment.

MicroRNAs Profiling in HIV, HCV, and HIV/HCV Co-Infected Patients

BACKGROUND

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections are important public health issues.

OBJECTIVE

This study aimed to assess the association between microRNAs expression leveland immunological and viral markers in HIV, HCV, and HIV/HCV co-infected patients.

METHODS

The expression level of miR-29, miR-149, miR-199, miR-let7, miR-223, miR-155, miR-122, and miR-150 was evaluated in 20 HIV, 20 HCV, 20 co-infected patients, and 20 healthy controls using real-time PCR assay. HIV and HCVviral loads were measuredby real-time PCR, and also, CD4+ T-lymphocyte count was measuredby the PIMA CD4 analyzer.

RESULTS

The miRNA expression pattern in each mentioned group showed significantly different expression profiles, but some miRNA species were shared between the groups. MiR-122 and miR-155 were upregulated, while miR-29 and miR-223 were downregulated in three patients groups compared to healthy controls. A significant positive correlation was observed between the expression of miR-122 and HIV/HCV loads. But, miR-29 and let-7 were negatively correlated with HIV load, and miR-149 and let-7 were negatively correlated with HCV load. Also, miR-155 was positively correlated with HCV load. MiR-122 and miR-199 were negative while others were positively correlated with CD4+ T cell count.

CONCLUSION

These miRNAs are probably involved in the clinical progression and pathogenesis of HIV and HCV infections. Therefore, determining and manipulating these miRNAs can lead to opening a new gate to control these important infections.

Role of Exosomal miRNAs in Heart Failure

Heart failure is the terminal outcome of the majority of cardiovascular diseases, which lacks specific diagnostic biomarkers and therapeutic targets. It contributes to most of cardiovascular hospitalizations and death despite of the current therapy. Therefore, it is important to explore potential molecules improving the diagnosis and treatment of heart failure. MicroRNAs (miRNAs) are small non-coding RNAs that have been reported to be involved in regulating processes of heart failure. After the discovery of miRNAs in exosomes, the subcellular distribution analysis of miRNAs is raising researchers' attention. Growing evidence demonstrates that exosomal miRNAs may be promising diagnostic and therapeutic molecules for heart failure. This review summarizes the role of exosomal miRNAs in heart failure in the prospect of molecular and clinical researches.

The role of HPV gene expression and selected cellular MiRNAs in lung cancer development

BACKGROUND

The high mortality rate of lung cancer can be justified that strong need to explore new aspect of tumor biology. Human papillomavirus (HPV) has been detected as risk factor for the development of lung cancer. The aim of this study was to determine the role of HPV and cellular/miRNAs genes expression in the epithelial-mesenchymal transition (EMT) and development of lung cancer.

METHODS

In this case-control study, 109 lung cancer tissue and 52 controls were included. We analyzed the presence of HPV infection, its genotypes (in positive samples) and the expression of viral genes (E2, E6 and E7). Also, We examined the expression of celluar factors including (a) p53 and retinoblastoma (Rb) (as anti-carcinogenic genes), (b) EMT related genes, (c) selected miRNAs.

RESULTS

Our results reported 51.4% and 23.1% of HPV genome in tumor tissues and control tissues samples, respectively. There was a significant association between the HPV positive status and lung cancer (OR = 3.26, 95% C.I = 1.47-7.02, P = 0.001). HPV type 16 was the most prevalent genotype in tissues. The expression of p53, RB, TIMP1, CCNG-1, E-cad and PTPN13 were decreased while MMP-2 and N-cad were increased in HPV-positive tumor/control tissues compared to HPV-negative tissues. Also, among miRNAs, let-7, miR-23, miR-34, miR-125, miR-146 were downregulated and miR-20, miR-424 were upregulated in HPV-positve tissues compared to HPV-negative tissues.

CONCLUSION

This study demonstrated that HPV infection and interaction with cellular genes and miRNAs promote EMT which involved in the lung cancer development.

Transfer of miR-15a-5p by placental exosomes promotes pre-eclampsia progression by regulating PI3K/AKT signaling pathway via CDK1

Preeclampsia (PE) is a systemic complication that occurs after the 20th week of gestation and is characterized by the onset of hypertension and proteinuria. Dysregulated circulating microRNA (miRNA) has usually been noted in PE. Understanding the release profile and bioactivity of placental exosomes is a promising mode of identifying dysregulated miRNA, which may be useful biomarkers of PE. Herein, we aimed to investigate the role of placental exosomes and their miRNA cargo miR-15a-5p in PE. miR-15a-5p was found upregulated in exosomes isolated from maternal plasma of PE pregnant women as compared to those from normal pregnant women. Placental exosomes derived from PE pregnant women suppressed the proliferation and invasion of HTR-8/SVneo cells but promoted cell apoptosis, which was dictated by their cargo miR-15a-5p. Further investigation showed that exosomal miR-15a-5p inhibited the activation of the PI3K/AKT pathway by down-regulating CDK1, thus suppressing HTR-8/SVneo cell proliferation, invasion, and apoptosis. In vivo analysis demonstrated that placental exosomes treated with miR-15a-5p inhibitor attenuated histopathologic changes and apoptosis in the placenta of PE mice. In conclusion, these results provided evidence that transfer of miR-15a-5p by placental exosomes could be a promising therapeutic target to combat PE.