The crosstalk between IL-22 signaling and miR-197 in human keratinocytes

Human Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes Loaded Mir-29-3p Targets AhR to Improve Juvenile Idiopathic Arthritis via Inhibiting the Expression of IL-22 in CD4+ T Cell

BACKGROUND

Juvenile idiopathic arthritis (JIA) is one of the most common chronic inflammatory rheumatic diseases in children. Human umbilical cord mesenchymal stem cells (HUCMSCs)-derived exosomes (HUCMSCs-Exos) are involved in autoimmune diseases. This study investigates the mechanism of HUCMSC-Exos in improving JIA by targeting AhR through delivery of miR-29-3p to inhibit IL-22 expression in CD4+ T cells.

METHODS

Collagen induced arthritis (CIA) mouse model was established, and mice were treated with HUCMSCs-Exos and miR-29-3p antagomir, respectively. CD4+ T cells from JIA patients were used for cell experiments. The mechanism was elucidated by histopathological staining, transmission electron microscopy (TEM), immunohistochemistry, CCK-8 assay, flow cytometry, Western blotting, real-time PCR, and enzyme-linked immunosorbent assay (ELISA), laser confocal microscopy, and luciferase assay.

RESULT

JIA-CD4+ T cells showed higher expression of IL-22 and lower the levels of miR-29-3p, while HUCMSCs-Exos significantly inhibited the expression of IL-22 and increased the levels of miR-29a-3p, miR-29b-3p, and miR-29c-3p in CD4+ T cells from JIA patients. The expression of miR-29a-3p, miR-29b-3p, miR-29c-3p, AhR, and IL-22 in CD4+ T cells was significantly reversed when co-cultured with HUCMSCs transfected with miR-29-3p mimic or miR-29-3p inhibitor. In vivo experiment, HUCMSCs-Exos ameliorated CIA mice by delivering miR-29-3p to inhibit AhR, IL-22, IL-22R1, MMP3, and MMP13 expression. Furthermore, HUCMSCs-Exos also deliver miR-29-3p targeting AhR expression to inhibit IL-22 in JIA-CD4 + T cells through alleviating arthritic synovial fibroblast activation.

CONCLUSION

HUCMSCs-Exos loaded miR-29-3p targets AhR to improve JIA via inhibiting the expression of IL-22 in CD4+ T cell, which provides a scientific basis for the treatment of JIA.

The role of IL-22 in cancer

Interleukin-22, discovered in the year of 2000, is a pleiotropic Th17 cytokine from the IL-10 family of cytokines. IL-22 signals through the type 2 cytokine receptor complex IL-22R and predominantly activates STAT3. This pathway leads to the transcription of several different types of genes, giving IL-22 context-specific functions ranging from inducing antimicrobial peptide expression to target cell proliferation. In recent years, it has been shown that IL-22 is involved in the pathogenesis of neoplasia in some cancers through its pro-proliferative and anti-apoptotic effects. This review highlights studies with recent discoveries and conclusions drawn on IL-22 and its involvement and function in various cancers. Such a study may be helpful to better understand the role of IL-22 in cancer so that new treatment could be developed targeting IL-22.

An overview of Skp2: a promising new therapeutic target of psoriasis

INTRODUCTION

Psoriasis is a chronic immune-mediated disorder affecting over 2-3% of the population worldwide, significantly impacting quality of life. Despite the availability of various therapeutic interventions, concerns persist regarding lesion recurrence and potential alterations in immune surveillance promoting cancer progression. Recent advancements in understanding cellular and molecular pathways have unveiled key factors in psoriasis etiology, including IL-17, 22, 23, TNF-α, PDE-4, JAK-STAT inhibitors, and AhR agonists. This work explores the potential of S-phase kinase-associated protein 2 (Skp2) as a therapeutic target in psoriasis.

AREA COVERED

This review covers the current understanding of psoriasis pathophysiology, including immune dysregulation, and the role of keratinocytes and ubiquitin. It also delves into Skp2 role in cell cycle regulation, and its correlation with angiogenesis and ubiquitin in psoriasis. The evolving therapeutic approaches targeting Skp2, including small molecule inhibitors, are also discussed.

EXPERT OPINION

Targeting Skp2 holds promise for developing novel therapeutic approaches for psoriasis. By modulating Skp2 activity or expression, it may be possible to intervene in inflammatory and proliferative processes underlying the disease. Further research into Skp2 inhibitors and their efficacy in preclinical and clinical settings is warranted to harness the full potential of Skp2 as a therapeutic target in psoriasis management.

WTAP mediated m6A-modified circ_0056856 contributes to the proliferation, migration, and invasion of IL-22-stimulated human keratinocyte by miR-197-3p/CDK1 axis

BACKGROUND

Psoriasis is a chronic inflammation-associated skin disorder, and interleukin-22 (IL-22) is involved in psoriasis pathogenesis by boosting the proliferation and migration of keratinocytes. Mounting evidence has shown that circRNAs might play an important role in several aspects of psoriasis. This study is designed to explore the role and mechanism of circ_0056856 in regulating the phenotypes of IL-22-induced keratinocytes (HaCaT cells).

METHODS

Circ_0056856, microRNA-197-3p (miR-197-3p), Cyclin-dependent kinase 1 (CDK1), and Wilms tumor 1-associated protein (WTAP) levels were detected using real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, proliferation, migration, and invasion were analyzed using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), Wound scratch, and Transwell assays. After being predicted by Circinteractome or TargetScan, binding between miR-197-3p and circ_0056856 or CDK1 was verified by a dual-luciferase reporter assay. CDK1 and WTAP protein levels were determined using Western blot. Interaction between WTAP and circ_0056856 was assessed using methylated RNA immunoprecipitation (MeRIP) assay.

RESULTS

Increased circ_0056856, CDK1, and WTAP were observed in psoriasis patients and IL-22-treated HaCaT cells. Moreover, circ_0056856 knockdown might repress IL-22-induced HaCaT cell proliferation, migration, and invasion in vitro. In mechanism, circ_0056856 might function as a sponge of miR-197-3p to modulate CDK1 expression, and WTAP improved circ_0056856 expression via m6A methylation.

CONCLUSION

WTAP-guided m6A modified circ_0056856 facilitates IL-22-stimulated HaCaT cell damage through the miR-197-3p/CDK1 axis, which could provide novel insights into psoriasis treatment.

γδ T Cells Mediate a Requisite Portion of a Wound Healing Response Triggered by Cutaneous Poxvirus Infection

Infection at barrier sites, e.g., skin, activates local immune defenses that limit pathogen spread, while preserving tissue integrity. Phenotypically distinct γδ T cell populations reside in skin, where they shape immunity to cutaneous infection prior to onset of an adaptive immune response by conventional αβ CD4+ (TCD4+) and CD8+ (TCD8+) T cells. To examine the mechanisms used by γδ T cells to control cutaneous virus replication and tissue pathology, we examined γδ T cells after infection with vaccinia virus (VACV). Resident γδ T cells expanded and combined with recruited γδ T cells to control pathology after VACV infection. However, γδ T cells did not play a role in control of local virus replication or blockade of systemic virus spread. We identified a unique wound healing signature that has features common to, but also features that antagonize, the sterile cutaneous wound healing response. Tissue repair generally occurs after clearance of a pathogen, but viral wound healing started prior to the peak of virus replication in the skin. γδ T cells contributed to wound healing through induction of multiple cytokines/growth factors required for efficient wound closure. Therefore, γδ T cells modulate the wound healing response following cutaneous virus infection, maintaining skin barrier function to prevent secondary bacterial infection.

Serum microRNA profile of rhesus macaques following ionizing radiation exposure and treatment with a medical countermeasure, Ex-Rad

Exposure to ionizing radiation (IR) presents a formidable clinical challenge. Total-body or significant partial-body exposure at a high dose and dose rate leads to acute radiation syndrome (ARS), the complex pathologic effects that arise following IR exposure over a short period of time. Early and accurate diagnosis of ARS is critical for assessing the exposure dose and determining the proper treatment. Serum microRNAs (miRNAs) may effectively predict the impact of irradiation and assess cell viability/senescence changes and inflammation. We used a nonhuman primate (NHP) model-rhesus macaques (Macaca mulatta)-to identify the serum miRNA landscape 96 h prior to and following 7.2 Gy total-body irradiation (TBI) at four timepoints: 24, 36, 48, and 96 h. To assess whether the miRNA profile reflects the therapeutic effect of a small molecule ON01210, commonly known as Ex-Rad, that has demonstrated radioprotective efficacy in a rodent model, we administered Ex-Rad at two different schedules of NHPs; either 36 and 48 h post-irradiation or 48 and 60 h post-irradiation. Results of this study corroborated our previous findings obtained using a qPCR array for several miRNAs and their modulation in response to irradiation: some miRNAs demonstrated a temporary increased serum concentration within the first 24-36 h (miR-375, miR-185-5p), whereas others displayed either a prolonged decline (miR-423-5p) or a long-term increase (miR-30a-5p, miR-27b-3p). In agreement with these time-dependent changes, hierarchical clustering of differentially expressed miRNAs showed that the profiles of the top six miRNA that most strongly correlated with radiation exposure were inconsistent between the 24 and 96 h timepoints following exposure, suggesting that different biodosimetry miRNA markers might be required depending on the time that has elapsed. Finally, Ex-Rad treatment restored the level of several miRNAs whose expression was significantly changed after radiation exposure, including miR-16-2, an miRNA previously associated with radiation survival. Taken together, our findings support the use of miRNA expression as an indicator of radiation exposure and the use of Ex-Rad as a potential radioprotectant.

The role of microRNA in psoriasis: A review

Psoriasis is a chronic immune-mediated inflammatory skin disease that involves a complex interplay between infiltrated immune cells and keratinocytes. Great progress has been made in the research on the molecular mechanism of coding and non-coding genes, which has helped in clinical treatment. However, our understanding of this complex disease is far from clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that are involved in post-transcriptional regulation, characterised by their role in mediating gene silencing. Recent studies on miRNAs have revealed their important role in the pathogenesis of psoriasis. We reviewed the current advances in the study of miRNAs in psoriasis; the existing research has found that dysregulated miRNAs in psoriasis notably affect keratinocyte proliferation and/or differentiation processes, as well as inflammation progress. In addition, miRNAs also influence the function of immune cells in psoriasis, including CD4+ T cells, dendritic cells, Langerhans cells and so on. In addition, we discuss possible miRNA-based therapy for psoriasis, such as the topical delivery of exogenous miRNAs, miRNA antagonists and miRNA mimics. Our review highlights the potential role of miRNAs in the pathogenesis of psoriasis, and we expect more research progress with miRNAs in the future, which will help us understand this complex skin disease more accurately.

miRNome and Proteome Profiling of Human Keratinocytes and Adipose Derived Stem Cells Proposed miRNA-Mediated Regulations of Epidermal Growth Factor and Interleukin 1-Alpha

Wound healing is regulated by complex crosstalk between keratinocytes and other cell types, including stem cells. In this study, a 7-day direct co-culture model of human keratinocytes and adipose-derived stem cells (ADSCs) was proposed to study the interaction between the two cell types, in order to identify regulators of ADSCs differentiation toward the epidermal lineage. As major mediators of cell communication, miRNome and proteome profiles in cell lysates of cultured human keratinocytes and ADSCs were explored through experimental and computational analyses. GeneChip^® miRNA microarray, identified 378 differentially expressed miRNAs; of these, 114 miRNAs were upregulated and 264 miRNAs were downregulated in keratinocytes. According to miRNA target prediction databases and the Expression Atlas database, 109 skin-related genes were obtained. Pathway enrichment analysis revealed 14 pathways including vesicle-mediated transport, signaling by interleukin, and others. Proteome profiling showed a significant upregulation of the epidermal growth factor (EGF) and Interleukin 1-alpha (IL-1α) compared to ADSCs. Integrated analysis through cross-matching the differentially expressed miRNA and proteins suggested two potential pathways for regulations of epidermal differentiation; the first is EGF-based through the downregulation of miR-485-5p and miR-6765-5p and/or the upregulation of miR-4459. The second is mediated by IL-1α overexpression through four isomers of miR-30-5p and miR-181a-5p.

The Role of T Helper 22 Cells in Dermatological Disorders

T helper 22 (Th22) cells are a newly identified subset of CD4+ T cells that secrete the effector cytokine interleukin 22 (IL-22) upon specific antigen stimulation, barely with IFN-γ or IL-17. Increasing studies have demonstrated that Th22 cells and IL-22 play essential roles in skin barrier defense and skin disease pathogenesis since the IL-22 receptor is widely expressed in the skin, especially in keratinocytes. Herein, we reviewed the characterization, differentiation, and biological activities of Th22 cells and elucidated their roles in skin health and disease. We mainly focused on the intricate crosstalk between Th22 cells and keratinocytes and provided potential therapeutic strategies targeting the Th22/IL-22 signaling pathway.

Identification of potential key molecules and signaling pathways for psoriasis based on weighted gene co-expression network analysis

BACKGROUND

Psoriasis is a chronic inflammatory skin disease, the pathogenesis of which is more complicated and often requires long-term treatment. In particular, moderate to severe psoriasis usually requires systemic treatment. Psoriasis is also associated with many diseases, such as cardiometabolic diseases, malignant tumors, infections, and mood disorders. Psoriasis can appear at any age, and lead to a substantial burden for individuals and society. At present, psoriasis is still a treatable, but incurable, disease. Previous studies have found that microRNAs (miRNAs) play an important regulatory role in the progression of various diseases. Currently, miRNAs studies in psoriasis and dermatology are relatively new. Therefore, the identification of key miRNAs in psoriasis is helpful to elucidate the molecular mechanism of psoriasis.

AIM

To identify key molecular markers and signaling pathways to provide potential basis for the treatment and management of psoriasis.

METHODS

The miRNA and mRNA data were obtained from the Gene Expression Omnibus database. Then, differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) were screened out by limma R package. Subsequently, DEmRNAs were analyzed for Gene Ontology and Kyoto Encyclopedia of Genes and Genomics functional enrichment. The “WGCNA” R package was used to analyze the co-expression network of all miRNAs. In addition, we constructed miRNA-mRNA regulatory networks based on identified hub miRNAs. Finally, in vitro validation was performed. All experimental procedures were approved by the ethics committee of Chinese PLA General Hospital (S2021-012-01).

RESULTS

A total of 639 DEmRNAs and 84 DEmiRNAs were identified. DEmRNAs screening criteria were adjusted P (adj. P) value < 0.01 and |logFoldChange| (|logFC|) > 1. DEmiRNAs screening criteria were adj. P value < 0.01 and |logFC| > 1.5. KEGG functional analysis demonstrated that DEmRNAs were significantly enriched in immune-related biological functions, for example, toll-like receptor signaling pathway, cytokine-cytokine receptor interaction, and chemokine signaling pathway. In weighted gene co-expression network analysis, turquoise module was the hub module. Moreover, 10 hub miRNAs were identified. Among these 10 hub miRNAs, only 8 hub miRNAs predicted the corresponding target mRNAs. 97 negatively regulated miRNA-mRNA pairs were involved in the miRNA-mRNA regulatory network, for example, hsa-miR-21-5p-claudin 8 (CLDN8), hsa-miR-30a-3p-interleukin-1B (IL-1B), and hsa-miR-181a-5p/hsa-miR-30c-2-3p-C-X-C motif chemokine ligand 9 (CXCL9). Real-time polymerase chain reaction results showed that IL-1B and CXCL9 were up-regulated and CLDN8 was down-regulated in psoriasis with statistically significant differences.

CONCLUSION

The identification of potential key molecular markers and signaling pathways provides potential research directions for further understanding the molecular mechanisms of psoriasis. This may also provide new research ideas for the prevention and treatment of psoriasis in the future.

CircMMD_007 promotes oncogenic effects in the progression of lung adenocarcinoma through microRNA-197-3p/protein tyrosine phosphatase non-receptor type 9 axis

Circular RNAs play important roles in cancer biology. In this research, we explored the underlying function and mechanism of cirMMD_007 in lung adenocarcinoma (LC). Clinical lung adenocarcinoma samples were obtained from surgery. Bioinformatic databases were used to predict miRNAs that can potentially target circRNAs and miRNA target genes. hsa_circMMD_007, miR-197-3p, and PTPN9 mRNA expressions were investigated by qRT-PCR. Protein expressions were examined using Western blot. The proliferation abilities were assessed by Cell Counting Kit-8 assays. Wound healing cell migration assay was applied to evaluate cell migration ability. Luciferase reporter assay and rescue experiments were then performed to elucidate the underlying mechanism. We found that the expression of circMMD_007 was abnormally increased in LC. The expression of circMMD_007 was higher in advanced stages. Knockout of circMMD_007 hindered the tumorigenesis of LC in vivo and in vitro. circMMD_007 could negatively regulate the expression of miR-197-3p. PTPN9 behaved to be a molecular target of miR-197-3p. In summary, this research demonstrated that circular RNA circMMD_007 could promote the oncogenic effects in the progression of LC through miR-197-3p/PTPN9 axis.

Circulating microRNA-197-3p as a potential biomarker for asbestos exposure

Asbestos is considered the main cause of diseases in workers exposed to this mineral in the workplace as well as an environmental pollutant. The association between asbestos and the onset of different diseases has been reported, but asbestos exposure specific biomarkers are not known. MicroRNAs (miRNAs) are small, single-strand, non-coding RNAs, with potential value as diagnostic, prognostic, and predictive markers in liquid biopsies. Sera collected from workers ex-exposed to asbestos (WEA) fibers were compared with sera from healthy subjects (HS) of similar age, as liquid biopsies. The expression of the circulating miRNA 197-3p was investigated employing two different highly analytical PCR methods, i.e. RT-qPCR and ddPCR. MiR-197-3p levels were tested in sera from WEA compared to HS. MiR-197-3p tested dysregulated in sera from WEA (n = 75) compared to HS (n = 62). Indeed, miR-197-3p was found to be 2.6 times down-regulated in WEA vs. HS (p = 0.0001***). In addition, an inverse correlation was detected between miR-197-3p expression level and cumulative asbestos exposure, being this miRNA down-regulated 2.1 times in WEA, with high cumulative asbestos exposure, compared to WEA with low exposure (p = 0.0303*). Circulating miR-197-3p, found to be down regulated in sera from WEA, is proposed as a new potential biomarker of asbestos exposure.

MicroRNA profiling of psoriatic skin identifies 11 miRNAs associated with disease severity

MicroRNAs (miRNAs) are small non-coding RNAs that have emerged as central regulators of gene expression and powerful biomarkers of disease. Much is yet unknown about their role in psoriasis pathology. To globally characterize the miRNAome of psoriatic skin, skin biopsies were collected from psoriatic cases (n = 75) and non-psoriatic controls (n = 46) and RNA sequenced. Count data were meta-analysed with a previously published dataset (cases, n = 24, controls, n = 20), increasing the number of psoriatic cases fourfold from previously published studies. Differential gene expression analyses were performed comparing lesional psoriatic (PP), non-lesional psoriatic (PN) and control (NN) skin. Further, functional enrichment and cell-specific analyses were performed. Across all contrasts, we identified 439 significantly differentially expressed miRNAs (DEMs), of which 85 were novel for psoriasis and 11 were related to disease severity. Meta-analyses identified 20 DEMs between PN and NN, suggesting an inherent change in the constitution of all skin in psoriasis. By integrating the miRNA transcriptome with mRNA target interactions, we identified several functionally enriched terms, including "thyroid hormone signalling," "insulin resistance" and various infectious diseases. Cell-specific expression analyses revealed that the upregulated DEMs were enriched in epithelial and immune cells. This study provides the most comprehensive overview of the miRNAome in psoriatic skin to date and identifies a miRNA signature related to psoriasis severity. Our results may represent molecular links between psoriasis and related comorbidities and have outlined potential directions for future functional studies to identify biomarkers and treatment targets.

miR-21-3p/IL-22 Axes Are Major Drivers of Psoriasis Pathogenesis by Modulating Keratinocytes Proliferation-Survival Balance and Inflammatory Response

Psoriasis is a chronic inflammatory skin disease that is mediated by complex crosstalk between immune cells and keratinocytes (KCs). Emerging studies have showed a specific psoriatic microRNAs signature, in which miR-21 is one of the most upregulated and dynamic miRNAs. In this study, we focused our investigations on the passenger miR-21-3p strand, which is poorly studied in skin and in psoriasis pathogenesis. Here, we showed the upregulation of miR-21-3p in an IMQ-induced psoriasiform mouse model. This upregulation was correlated with IL-22 expression and functionality, both in vitro and in vivo, and it occurred via STAT3 and NF-κB signaling. We identified a network of differentially expressed genes involved in abnormal proliferation control and immune regulatory genes implicated in the molecular pathogenesis of psoriasis in response to miR-21-3p overexpression in KCs. These results were confirmed by functional assays that validated the proliferative potential of miR-21-3p. All these findings highlight the importance of miR-21-3p, an underestimated miRNA, in psoriasis and provide novel molecular targets for therapeutic purposes.

Involvement of miR-214-3p/FOXM1 Axis During the Progression of Psoriasis

Psoriasis is a common, chronic, and relapsing skin disease characterized by hyperproliferation of keratinocytes and apoptosis delay. However, the molecular mechanisms underlying the progression of psoriasis remain elusive. MicroRNAs (miRNAs) are single-stranded, small non-coding RNAs that play a crucial role in the development of psoriasis by promoting targeted mRNA degradation or translational inhibition. Here, we report that miR-214-3p, one of the downregulated miRNAs identified in the skin of psoriatic patients and imiquimod (IMQ)-induced mouse models, can negatively regulate the expression of forkhead box M1 (FOXM1). miR-214-3p inhibition leads to hyperproliferation and increased apoptosis of keratinocytes in vitro. Moreover, we show that miR-214-3p inhibition causes an arrest of the cell cycle at the S stage by elevating the expression of NEK2, KIF20A, CENP-A, CENP-F, and Cyclin B1 and by reducing the expression of Cyclin D1 in HaCaT cells. In vivo, the administration of miR-214-3p attenuates the psoriasis-like phenotype in IMQ-induced mice. Collectively, our results suggest that miR-214-3p/FOXM1 axis in keratinocytes could be a novel target in the treatment of psoriasis.

A case-control study on correlation between the single nucleotide polymorphism of CLEC4E and the susceptibility to tuberculosis among Han people in Western China

BACKGROUND

Tuberculosis (TB) is one of the leading causes of morbidity and mortality in Western China. Preclinical studies have suggested the protective effect of the C-type lectin receptor of family 4 member E (CLEC4E) from TB. Herein, we investigated the association between CLEC4E gene variants and TB susceptibility in a western Chinese Han population.

METHODS

We genotyped four single nucleotide polymorphisms (SNPs) rs10841856, rs10770847, rs10770855 and rs4480590 in the CLEC4E gene using the improved multiplex ligation detection reaction (iMLDR) assay in 900 TB cases and 1534 healthy controls.

RESULTS

After stratifying the whole data by sex, it was found that males exhibited mutant allele G of rs10841856 was more strongly associated with increased TB risk after Bonferroni correction (OR = 1.334, 95% CI: 1.142-1.560; P < 0.001 after adjusting for age; p = 0.001 after Bonferroni correction). The genetic model analysis found that rs10841856 was associated with the increased risk of TB among males under the dominant model (OR = 1.557, 95% CI = 1.228-1.984, P < 0.001 after adjusting for age, P < 0.001 after Bonferroni correction). Bioinformatics analysis suggested that rs10841856 might fall in putative functional regions and might be the expression quantitative trait loci (eQTL) for CLEC4E and long noncoding RNA RP11-561P12.5.

CONCLUSIONS

Our study revealed that rs10841856 in the CLEC4E gene might be related to increased TB risk, especially the dominant genetic model among male Han individuals from Western China.

Triple-Helical Binding of Peptide Nucleic Acid Inhibits Maturation of Endogenous MicroRNA-197

Sequence specific recognition and functional inhibition of biomedically relevant double-helical RNAs is highly desirable but remains a formidable problem. The present study demonstrates that electroporation of a triplex-forming peptide nucleic acid (PNA), modified with 2-aminopyridine (M) nucleobases, inhibited maturation of endogenous microRNA-197 in SH-SY5Y cells, while having little effect on maturation of microRNA-155 or -27a. In vitro RNA binding and Dicer inhibition assays suggested that the observed biological activity was most likely due to a sequence-specific PNA-RNA triplex formation that inhibited the activity of endonucleases responsible for microRNA maturation. The present study is the first example of modulation of activity of endogenous noncoding RNA using M-modified triplex-forming PNA.

H3K27Ac modification and gene expression in psoriasis

BACKGROUND

Numerous alterations in gene expression have been described in psoriatic lesions compared to uninvolved or healthy skin. However, the mechanisms which induce this altered expression remain unclear. Epigenetic modifications play a key role in regulating genes' expression. Only three studies compared the whole-genome DNA methylation of psoriasis versus healthy skin. The present is the first study of genome-wide comparison of histone modifications between psoriatic to healthy skins.

OBJECTIVE

Our objective was to explore the pattern of H3K27Ac modifications in psoriatic lesions compared to uninvolved psoriatic and healthy skin, in order to identify new genes involved in the pathogenesis of psoriasis.

METHOD

Using ChIP-seq with anti H3K27Ac we compared the acetylation of lysine 27 on histone 3 (H3K27Ac) modification between psoriatic to healthy skins, combined with mRNA array.

RESULTS

We found a differential H3K27Ac pattern between psoriatic compared to uninvolved or healthy skins. We found that many of the overexpressed and H3K27Ac enriched genes in psoriasis, harbor a putative GRHL transcription factor-binding site.

CONCLUSIONS

In the most overexpressed genes in psoriasis, there is an enrichment of H3K27Ac. However, the loss of H3K27 acetylation modification does not correlate with decreased gene expression. GRHL appears to play an important role in the pathogenesis of psoriasis and therefore, might be a new target for psoriasis therapeutics.

Study of miRNA interactome in active rheumatoid arthritis patients reveals key pathogenic roles of dysbiosis in the infection-immune network

OBJECTIVES

To characterize serum microRNA (miR) and the miR interactome of active RA patients in RA aetiology and pathogenesis.

METHODS

The differentially expressed miRs (DEmiRs) in serum of naïve active RA patients (NARAPs, n = 9, into three pools) vs healthy controls (HCs, n = 15, into five pools) were identified with Agilent human miR microarray analysis. Candidate driver genes in epigenetic and pathogenic signalling pathway modules for RA were analysed using miRTarBase and a molecular complex detection algorithm. The interactome of these DEmiRs in RA pathogenesis were further characterized with gene ontology and Kyoto Encyclopaedia of Genes and Genomes.

RESULTS

Three upregulated DEmiRs (hsa-miR-187-5p, -4532, -4516) and eight downregulated DEmiRs (hsa-miR-125a-3p, -575, -191-3p, -6865-3p, -197-3p, -6886-3p, -1237-3p, -4436b-5p) were identified in NARAPs. Interactomic analysis from heterogeneous experimentally validated sources yielded 1719 miR-target interactions containing 5.67% strong and 94.33% less strong experimental evidence. Gene ontology and Kyoto Encyclopaedia of Genes and Genomes analyses allocated the upregulated DEmiRs in the infection modules and the downregulated DEmiRs in the immune signalling pathways. Specifically, these DEmiRs revealed the significant contributions of the intestinal microbiome dysbiosis in the infection-inflammation-immune network for activation of T cells, immune pathways of IL-17, Toll-like receptor, TNF, Janus kinase-signal transducer and activator of transcription, osteoclast cell differentiation pathway and IgA production to the active RA pathogenesis.

CONCLUSIONS

Our experiment-based interactomic study of DEmiRs in serum of NARAPs revealed novel clinically relevant miRs interactomes in the infection-inflammation-immune network of RA. These results provide valuable resources for understanding the integrated function of the miR network in RA pathogenesis and the application of circulating miRs as biomarkers for early aetiologic RA diagnosis.

Insights into interplay of immunopathophysiological events and molecular mechanistic cascades in psoriasis and its associated comorbidities

Psoriasis is an inflammatory skin disease with complex pathogenesis and multiple etiological factors. Besides the essential role of autoreactive T cells and constellation of cytokines, the discovery of IL-23/Th17 axis as a central signaling pathway has unraveled the mechanism of accelerated inflammation in psoriasis. This has provided insights into psoriasis pathogenesis and revolutionized the development of effective biological therapies. Moreover, genome-wide association studies have identified several candidate genes and susceptibility loci associated with this disease. Although involvement of cellular innate and adaptive immune responses and dysregulation of immune cells have been implicated in psoriasis initiation and maintenance, there is still a lack of unifying mechanism for understanding the pathogenesis of this disease. Emerging evidence suggests that psoriasis is a high-mortality disease with additional burden of comorbidities, which adversely affects the treatment response and overall quality of life of patients. Furthermore, changing trends of psoriasis-associated comorbidities and shared patterns of genetic susceptibility, risk factors and pathophysiological mechanisms manifest psoriasis as a multifactorial systemic disease. This review highlights the recent progress in understanding the crucial role of different immune cells, proinflammatory cytokines and microRNAs in psoriasis pathogenesis. In addition, we comprehensively discuss the involvement of various complex signaling pathways and their interplay with immune cell markers to comprehend the underlying pathophysiological mechanism, which may lead to exploration of new therapeutic targets and development of novel treatment strategies to reduce the disastrous nature of psoriasis and associated comorbidities.

IL6R is a target of miR-197 in human keratinocytes

Psoriasis is a chronic inflammatory disorder with cutaneous and systemic manifestations and substantial negative effects on patients' quality of life. MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression that play a role in the pathogenesis of psoriasis. Previously studies, from others and by us, highlighted specific miRNAs that are dysregulated in psoriatic lesions. MicroRNA-197-3p (miR-197) expression is downregulated in psoriatic lesions compared to normal or uninvolved skin in patients with psoriasis. We have previously reported that miR-197 could modulate IL-22 and IL-17 signalling in psoriasis. Herein, we identify additional biochemical targets of miR-197 in psoriasis. We applied a transcriptome-wide biochemical approach, Protein argonaute-2 photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (Ago2 PAR-CLIP), to search for new targets of miR-197 in live keratinocytes, and validated its results using reporter assay and analysing by Western blot protein levels in cells overexpressing miR-197. Ago2 PAR-CLIP identified biochemical targets of miR-197, including the alpha subunit of the IL-6 receptor (IL6R). This work provides evidence that IL6R in bona-fide biochemical target of miR-197. IL6R is known to be up-regulated in psoriasis and even was considered as a possible therapeutic target. From the present data and our previous studies, it appears that miR-197 is a major regulator of the interaction between immune system cells and keratinocytes.

Low Interleukin-22 Binding Protein Is Associated With High Mortality in Alcoholic Hepatitis and Modulates Interleukin-22 Receptor Expression

INTRODUCTION

In alcoholic hepatitis (AH), high interleukin (IL)-22 production is associated with disease improvement, purportedly through enhanced infection resistance and liver regeneration. IL-22 binding protein (BP) binds and antagonizes IL-22 bioactivity, but data on IL-22BP in liver disease suggest a complex interplay. Despite the scarcity of human data, IL-22 is in clinical trial as treatment of AH. We, therefore, in patients with AH, described the IL-22 system focusing on IL-22BP and associations with disease course, and mechanistically pursued the human associations in vitro.

METHODS

We prospectively studied 41 consecutive patients with AH at diagnosis, days 7 and 90, and followed them for up to 1 year. We measured IL-22 pathway proteins in liver biopsies and blood and investigated IL-22BP effects on IL-22 in hepatocyte cultures.

RESULTS

IL-22BP was produced in the gut and was identifiable in the patients with AH' livers. Plasma IL-22BP was only 50% of controls and the IL-22/IL-22BP ratio thus elevated. Consistently, IL-22-inducible genes were upregulated in AH livers at diagnosis. Low plasma IL-22BP was closely associated with high 1-year mortality. In vitro, IL-22 stimulation reduced IL-22 receptor (R) expression, but coincubation with IL-22BP sustained IL-22R expression. In the AH livers, IL-22R mRNA expression was similar to healthy livers, although IL-22R liver protein was higher at diagnosis.

DISCUSSION

Plasma IL-22BP was associated with an adverse disease course, possibly because its low level reduces IL-22R expression so that IL-22 bioactivity was reduced. This suggests the IL-BP interplay to be central in AH pathogenesis, and in future treatment trials (see Visual abstract, Supplementary Digital Content 5, http://links.lww.com/CTG/A338).

MicroRNA Expression in Cutaneous Lupus: A New Window to Understand Its Pathogenesis

Background

The role of miRNAs in the pathogenesis of cutaneous lupus has not been studied.

Objective

It was to assess the levels of a selected panel of circulating miRNAs that could be involved in the regulation of the immune response, inflammation, and fibrosis in cutaneous lupus.

Methods

It was a cross-sectional study. We included 22 patients with subacute (SCLE) and 20 with discoid (DLE) lesions, and 19 healthy donors (HD). qRT-PCR for miRNA analysis, flow cytometry in peripheral blood, and skin immunohistochemistry were performed to determine the distribution of CD4 T cells and regulatory cells and their correlation with circulating miRNAs.

Results

miR-150, miR-1246, miR-21, miR-23b, and miR-146 levels were downregulated in SCLE vs. HD. miR-150, miR-1246, and miR-21 levels were downregulated in DLE vs. HD. miR-150, miR-1246, and miR-21 levels were downregulated in DLE γ⁺ with miR-1246 in SCLE, whereas CD123⁺/CD196⁺/IDO⁺ cells were positively associated with miR-150 in DLE. In the tissue, CD4⁺/IL-4⁺ and CD20⁺/IL-10⁺ cells were positively associated with miR-21 and CD4⁺/IFN-γ⁺ with miR-1246 in SCLE, whereas CD123⁺/CD196⁺/IDO⁺ cells were positively associated with miR-150 in DLE. In the tissue, CD4⁺/IL-4⁺ and CD20⁺/IL-10⁺ cells were positively associated with miR-21 and CD4⁺/IFN-β, thyroid hormone, and cancer signaling pathways were shared between miR-21, miR-31, miR-23b, miR-146a, miR-1246, and miR-150.

Conclusions

A downregulation of miR-150, miR-1246, and miR-21 in both CLE varieties vs. HD. miR-150, miR-1246, and miR-21 levels were downregulated in DLE

Systems and Synthetic microRNA Biology: From Biogenesis to Disease Pathogenesis

MicroRNAs (miRNAs) are approximately 22-nucleotide-long, small non-coding RNAs that post-transcriptionally regulate gene expression. The biogenesis of miRNAs involves multiple steps, including the transcription of primary miRNAs (pri-miRNAs), nuclear Drosha-mediated processing, cytoplasmic Dicer-mediated processing, and loading onto Argonaute (Ago) proteins. Further, miRNAs control diverse biological and pathological processes via the silencing of target mRNAs. This review summarizes recent findings regarding the quantitative aspects of miRNA homeostasis, including Drosha-mediated pri-miRNA processing, Ago-mediated asymmetric miRNA strand selection, and modifications of miRNA pathway components, as well as the roles of RNA modifications (epitranscriptomics), epigenetics, transcription factor circuits, and super-enhancers in miRNA regulation. These recent advances have facilitated a system-level understanding of miRNA networks, as well as the improvement of RNAi performance for both gene-specific targeting and genome-wide screening. The comprehensive understanding and modeling of miRNA biogenesis and function have been applied to the design of synthetic gene circuits. In addition, the relationships between miRNA genes and super-enhancers provide the molecular basis for the highly biased cell type-specific expression patterns of miRNAs and the evolution of miRNA-target connections, while highlighting the importance of alterations of super-enhancer-associated miRNAs in a variety of human diseases.

Understanding psoriasis: Role of miRNAs

Psoriasis is a chronic, immune-mediated inflammatory skin disease, with a multifactorial etiology and important immunologic, genetic and environmental components. Psoriasis vulgaris represents its most common form, with a variable prevalence across the globe. Although its pathogenesis remains to be fully elucidated, a lack of balance in the epigenetic network has been shown to trigger certain elements of this disease, possibly altering its outcome. MicroRNAs are small non-coding RNA molecules involved in RNA-silencing and the post-transcriptional regulation of gene expression, which also appear to mediate the immune dysfunction in psoriasis. Although microRNA research is a new field in dermatology and psoriasis, there is rapidly accumulating evidence for its major contribution in the pathogenesis of chronic inflammatory conditions, including psoriasis and other dermatological disorders. Furthermore, circulating miRNAs identified in patients' blood samples have been identified as promising biomarkers of diagnosis, prognosis or treatment response. Extended investigations in this field are required, as until now, the exact involvement of miRNAs in psoriasis have remained to be entirely elucidated. This short review highlights a number of the roles of miRNAs found in different stages of psoriasis.

Bioinformatic Analysis of Potential Biomarkers for Spinal Cord-injured Patients with Intractable Neuropathic Pain

BACKGROUND

Neuropathic pain is one of the common complications after spinal cord injury (SCI), affecting individuals' quality of life. The molecular mechanism for neuropathic pain after SCI is still unclear. We aimed to discover potential genes and microRNAs (miRNAs) related to neuropathic pain by the bioinformatics method.

METHODS

Microarray data of GSE69901 were obtained from Gene Expression Omnibus (GEO) database. Peripheral blood samples from individuals with or without neuropathic pain after SCI were collected. Twelve samples from individuals with neuropathic pain and 13 samples from individuals without pain as controls were included in the downloaded microarray. Differentially expressed genes (DEGs) between the neuropathic pain group and the control group were detected using the GEO2R online tool. Functional enrichment analysis of DEGs was performed using the DAVID database. Protein-protein interaction network was constructed from the STRING database. MiRNAs targeting these DEGs were obtained from the miRNet database. A merged miRNA-DEG network was constructed and analyzed with Cytoscape software.

RESULTS

In total, 1134 DEGs were identified between individuals with or without neuropathic pain (case and control), and 454 biological processes were enriched. We identified 4 targeted miRNAs, including mir-204-5p, mir-519d-3p, mir-20b-5p, mir-6838-5p, which may be potential biomarkers for SCI patients.

CONCLUSION

Protein modification and regulation of the biological process of the central nervous system may be a risk factor in SCI. Certain genes and miRNAs may be potential biomarkers for the prediction of and potential targets for the prevention and treatment of neuropathic pain after SCI.

Clinicopathologic implication of microRNA-197 in diffuse large B cell lymphoma

Background

Diffuse large B cell lymphoma (DLBCL) contains heterogeneous subtypes with various molecular dysregulation at the gene, protein and microRNA levels. Compared with the GCB subtype, the non-germinal center B-like (non-GCB)/activated B cell-like (ABC) subtype exhibits frequent progression despite standard immunochemotherapy. We aimed to investigate the effects of miR-197 on the progression and chemosensitivity of DLBCL with respect to the GCB and non-GCB/ABC subtypes.

Methods

To screen distinctively expressed microRNAs, microRNA expression patterns were analyzed in 10 DLBCL cases by microarray chip assays. Using quantitative real-time polymerase chain reaction (qRT-PCR), associations between miR-197 expression levels and clinicopathologic variables were investigated in 51 DLBCL tissue samples. The effects of miR-197 on doxorubicin chemosensitivity were investigated using the OCI-Ly1 and SUDHL9 cell lines.

Results

MicroRNA expression profiling by hierarchical clustering revealed that miR-197 was one of the distinctively expressed microRNAs in DLBCL. Quantitative analysis using qRT-PCR revealed that miR-197 levels were not correlated with clinicopathologic variables, including the international prognostic index, but low miR-197 levels were significantly associated with lymphoma progression defined by refractoriness, relapse or death in the rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP)-treated subgroup (n = 43; p = 0.004). Among the three molecular groups, i.e., the GCB, non-GCB/miR-197^low and non-GCB/miR-197^high groups, progression was most frequently observed in the non-GCB/miR-197^low group in the full cohort (p = 0.013) and the R-CHOP cohort (p = 0.008). In survival analysis, low miR-197 levels were independently predictive of shorter progression-free survival in the R-CHOP cohort (p = 0.031; HR = 27.9) and the non-GCB subgroup (p = 0.037; HR = 21.5) but not in the GCB subgroup. Using SUDHL9 (ABC type) and OCI-Ly1 (GCB type) cells, the effects of doxorubicin on reducing cell viability were enhanced by miR-197 transfection. In apoptosis assays, miR-197 transfection enhanced doxorubicin-induced apoptosis in SUDHL9 cells but not in OCI-Ly1 cells, suggesting a chemosensitizing effect of miR-197 in ABC DLBCL.

Conclusions

These results suggest the role of miR-197 as a biomarker with potential therapeutic implications.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1537-0) contains supplementary material, which is available to authorized users.

Decreased neutrophil-associated miRNA and increased B-cell associated miRNA expression during tuberculosis

MicroRNAs are short non-coding RNAs that regulate gene expression by binding to, and suppressing the expression of genes. Research show that microRNAs have potential to be used as biomarkers for diagnosis, treatment response and can be used for therapeutic interventions. Furthermore, microRNA expression has effects on immune cell functions, which may lead to disease. Considering the important protective role of neutrophils and B-cells during M.tb infection, we evaluated the expression of microRNAs, known to alter function of these cells, in the context of human TB. We utilised real-time PCR to evaluate the levels of microRNA transcripts in the peripheral blood of TB cases and healthy controls. We found that neutrophil-associated miR-197-3p, miR-99b-5p and miR-191-5p transcript levels were significantly lower in TB cases. Additionally, B-cell-associated miR-320a, miR-204-5p, miR331-3p and other transcript levels were higher in TB cases. The miRNAs differentially expressed in neutrophils are predominantly implicated in signalling pathways leading to cytokine productions. Here, the decreased expression in TB cases may imply a lack of suppression on signalling pathways, which may lead to increased production of pro-inflammatory cytokines such as interferon-gamma. Furthermore, the miRNAs differentially expressed in B-cells are mostly involved in the induction/suppression of apoptosis. Further functional studies are however required to elucidate the significance and functional effects of changes in the expression of these microRNAs.

Bcl-3 induced by IL-22 via STAT3 activation acts as a potentiator of psoriasis-related gene expression in epidermal keratinocytes

IL-22 induces STAT3 phosphorylation and mediates psoriasis-related gene expression. However, the signaling mechanism leading from pSTAT3 to the expression of these genes remains unclear. We focused on Bcl-3, which is induced by STAT3 activation and mediates gene expression. In cultured human epidermal keratinocytes, IL-22 increased Bcl-3, which was translocated to the nucleus with p50 via STAT3 activation. The increases in CXCL8, S100As and human β-defensin 2 mRNA expression caused by IL-22 were abolished by siRNA against Bcl-3. Although CCL20 expression was also augmented by IL-22, the knockdown of Bcl-3 increased its level. Moreover, the combination of IL-22 and IL-17A enhanced Bcl-3 production, IL-22-induced gene expression, and the expression of other psoriasis-related genes, including those encoding IL-17C, IL-19, and IL-36γ. The expression of these genes (except for CCL20) was also suppressed by the knockdown of Bcl-3. Bcl-3 overexpression induced CXCL8 and HBD2 expression but not S100As expression. We also compared Bcl-3 expression between psoriatic skin lesions and normal skin. Immunostaining revealed strong signals for Bcl-3 and p50 in the nucleus of epidermal keratinocytes from psoriatic skin. The IL-22-STAT3-Bcl-3 pathway may be important in the pathogenesis of psoriasis.

Towards topical microRNA-directed therapy for epidermal disorders

There remains an unmet dermatological need for innovative topical agents that achieve better longterm outcomes with fewer side effects. Modulation of the expression and activity of microRNA (miRNAs) represents an emerging translational framework for the development of such innovative therapies because changes in the expression of one miRNA can have wide-ranging effects on diverse cellular processes associated with disease. In this short review, the roles of miRNA in epidermal development, psoriasis, cutaneous squamous cell carcinoma and re-epithelisation are highlighted. Consideration is given to the delivery of oligonucleotides that mimic or inhibit miRNA function using vehicles such as cell penetrating peptides, spherical nucleic acids, deformable liposomes and liquid crystalline nanodispersions. Formulation of miRNA-directed oligonucleotides with such skin-penetrating epidermal agents will drive the development of RNA-based cutaneous therapeutics for deployment as primary or adjuvant therapies for epidermal disorders.

Advances in the Application and Impact of MicroRNAs as Therapies for Skin Disease

The advent of RNA interference (RNAi) technology has profoundly impacted molecular biology research and medicine but has also advanced the field of skin care. Both effector molecules of RNAi, short-interfering RNA molecules and microRNAs (miRNAs), have been explored for their relative impact and utility for treating a variety of skin conditions. These post-transcriptional RNA regulatory molecules down-modulate protein expression through targeting of the 3' untranslated regions of messenger RNAs, leading to their degradation or repression through sequestration. As researchers hunt for genetic linkages to skin diseases, miRNA regulators have emerged as key players in the biology of keratinocytes, fibroblasts, melanocytes, and other cells of the skin. Herein, we attempt to coalesce the current efforts to combat various skin disorders and diseases through the development of miRNA-based technologies.

Two microRNA signatures for malignancy and immune infiltration predict overall survival in advanced epithelial ovarian cancer

MicroRNAs have been established as key regulators of tumor gene expression and as prime biomarker candidates for clinical phenotypes in epithelial ovarian cancer (EOC). We analyzed the coexpression and regulatory structure of microRNAs and their co-localized gene targets in primary tumor tissue of 20 patients with advanced EOC in order to construct a regulatory signature for clinical prognosis. We performed an integrative analysis to identify two prognostic microRNA/mRNA coexpression modules, each enriched for consistent biological functions. One module, enriched for malignancy-related functions, was found to be upregulated in malignant versus benign samples. The second module, enriched for immune-related functions, was strongly correlated with imputed intratumoral immune infiltrates of T cells, natural killer cells, cytotoxic lymphocytes, and macrophages. We validated the prognostic relevance of the immunological module microRNAs in the publicly available The Cancer Genome Atlas data set. These findings provide novel functional roles for microRNAs in the progression of advanced EOC and possible prognostic signatures for survival.

MiR-330 inhibits IL-22-induced keratinocyte proliferation through targeting CTNNB1

Psoriasis is a common chronic inflammatory skin disease which is characterized by hyperproliferation and aberrant differentiation of keratinocytes; however the exact pathogenesis is largely unknown. Interleukin-22 (IL-22) has demonstrated its vital role in T cell-mediated immune response by interacting with keratinocytes in the pathogenesis of psoriasis. The microRNAs (miRNAs) are a class of small non-coding RNA molecules that play important roles in cellular processes by regulating gene expression at the post-transcriptional level. MiR-330 has been reported to inhibit the proliferation and migration of mouse keratinocytes. In the present study, we indicated that miR-330 expression in lesion tissue of psoriasis patients was specifically down-regulated, and could inhibit IL-22-induced proliferation of HaCaT and HKC cell. Wnt/β-catenin pathway plays an essential role in the pathogenesis of psoriasis. By direct targeting CTNNB1, miR-330 could significantly downregulate IL-22-induced CTNNB1 expression. In addition, we found that the downstream targets of β-catenin, CyclinD1 and Axin2, could be affected by miR-330; miR-330 could suppress CyclinD1 protein expression and rescue Axin2 protein expression. Taken together, we indicated miR-330 inhibits IL-22-induced proliferation of HaCaT and HKC cell by targeting CTNNB1 and subsequently affect the downstream factors, CyclinD1 and Axin2 for the first time, and provide diagnostic markers and a novel target for psoriasis treatment.

IL-22-induced miR-122-5p promotes keratinocyte proliferation by targeting Sprouty2

Psoriasis is a common inflammatory skin disease, but the exact pathogenesis is largely unknown. Interleukin-22 (IL-22) has demonstrated its vital role in T-cell-mediated immune response by interacting with keratinocytes in the pathogenesis of psoriasis. Here, we showed the differentially expressed miRNAs and their potential targets in HaCaT cells stimulated by IL-22 using miRNA and mRNA microarrays. We revealed a total of 20 significantly changed (more than twofold) miRNAs in HaCaT cells and validated the results with quantitative reverse transcriptase PCR (qRT-PCR). We demonstrated that miR-122-5p was up-regulated both in HaCaT cells stimulated by IL-22 and in psoriatic lesions. Then, we aimed to investigate the biological roles and potential mechanism of miR-122-5p in keratinocytes. As a result, CCK-8 assay indicated that overexpression of miR-122-5p in keratinocytes promoted proliferation and conversely inhibition of endogenous miR-122-5p suppressed proliferation. According to the microarray analysis, we assumed that Sprouty2 (Spry2), a negative regulator of extracellular signal regulated kinase/mitogen-activated protein kinase signalling pathway, was a direct target gene of miR-122-5p. We found that the staining of Spry2 in cytoplasm was mainly localized in both basal and suprabasal layers of epidermis and showed a markedly decreased expression in psoriasis than in normal control by immunohistochemistry. Luciferase reporter and Western blot assays in HaCaT cells demonstrated that Spry2 was a direct target gene of miR-122-5p. In conclusion, IL-22-induced miR-122-5p promotes keratinocyte proliferation possibly by downregulating the expression of Spry2 thus playing important roles in the pathogenesis of psoriasis.

Anti-apoptotic effect of interleukin-22 on fibroblast-like synoviocytes in patients with rheumatoid arthritis is mediated via the signal transducer and activator of transcription 3 signaling pathway

AIM

Inadequate apoptosis of fibroblast-like synoviocytes (FLS) plays a crucial role in the immunopathogenesis of rheumatoid arthritis (RA). Interleukin-22 (IL-22) is a novel member of the cytokine network that has been found to be involved in the immunological process underlying RA. In this study, we investigated the effect of IL-22 on the survival of RA-FLS from RA patients and examined the possible mechanism to determine new therapeutic strategies for RA.

METHODS

FLS obtained from patients with RA were cultured in vitro and treated with sodium nitroprussiate (SNP) to induce apoptosis in the presence or absence of IL-22. RA-FLS viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RA-FLS apoptosis was analyzed by annexin V/propidium iodide staining (AV/PI). The levels of IL-22R1, pSTAT3-Y705, pSTAT3-S727, total STAT3, Bcl-xL and Bcl-2 were detected by Western blot analysis.

RESULTS

IL-22R1 was expressed on RA-FLS. IL-22 pretreatment at concentrations ranging from 10 to 100 ng/mL increased RA-FLS viability and prevented SNP-induced apoptosis. Treatment with the STAT3 inhibitors, HO3867 or STA21, reversed the protective effect of IL-22 on SNP-induced apoptosis of RA-FLS. IL-22-induced phosphorylation of STAT3 (pSTAT3-Y705 and pSTAT3-S727) was increased in RA-FLS. Also IL-22 increased Bcl-2 expression in SNP-treated RA-FLS, and the effect was reversed by treatment with HO3867 or STA21.

CONCLUSION

IL-22 protects against SNP-induced apoptosis in RA-FLS by activating the STAT3 pathway and the downstream target gene, Bcl-2. Therefore, therapeutic strategies that target the IL-22/STAT3 pathway are implicated as candidates for RA treatment.

Effect of Topical Administration of Fractions and Isolated Molecules from Plant Extracts on Skin Wound Healing: A Systematic Review of Murine Experimental Models

Background and Purpose. Skin wound healing is a dynamic process driven by molecular events responsible for the morphofunctional repair of the injured tissue. In a systematic review, we analyzed the relevance of plant fractions and isolates on skin wound healing. By revising preclinical investigations with murine models, we investigated if the current evidence could support clinical trials. Methods. Studies were selected in the MEDLINE/PubMed and Scopus databases according to the PRISMA statement. All 32 identified studies were submitted to data extraction and the methodological bias was investigated according to ARRIVE strategy. Results. The studies demonstrated that plant fractions and isolates are able to modulate the inflammatory process during skin wound healing, being also effective in attenuating the oxidative tissue damage in the scar tissue and stimulating cell proliferation, neoangiogenesis, collagen synthesis, granulation tissue expansion, reepithelialization, and the wound closure rate. However, we identified serious methodological flaws in all studies, such as the high level of reporting bias and absence of standardized experimental designs, analytical methods, and outcome measures. Conclusion. Considering these limitations, the current evidence generated from flawed methodological animal studies makes it difficult to determine the relevance of herbal medicines to treat skin wounds and derails conducting clinical studies.

MicroRNA-181b negatively regulates the proliferation of human epidermal keratinocytes in psoriasis through targeting TLR4

Our study aims to explore the role of microRNA‐181b (miR‐181b) and TLR in the regulation of cell proliferation of human epidermal keratinocytes (HEKs) in psoriasis. Twenty‐eight patients diagnosed with psoriasis vulgaris were selected as a case group with their lesional and non‐lesional skin tissues collected. A control group consisted of 20 patients who underwent plastic surgery with their healthy skin tissues collected. Real‐time quantitative fluorescence polymerase chain reaction (RT‐qPCR), in situ hybridization and immunohistochemistry were used to detect the expressions of miR‐181b and TLR4 in HEKs of healthy skin, psoriatic lesional skin and non‐lesional skin respectively. The 3′ untranslated region (3′UTR) of TLR4 combined with miR‐181b was verified by a dual‐luciferase reporter assay. Western blotting and bromodeoxyuridine were applied for corresponding detection of TLR4 expression and cell mitosis. The expression of miR‐181b in HEKs of psoriatic lesional skin was less than healthy skin and psoriatic non‐lesional skin. In psoriatic lesional and non‐lesional skin, TLR4‐positive cell rates and the number of positive cells per square millimetre were higher than healthy skin. The dual‐luciferase reporter assay verified that miR‐181b targets TLR4. HEKs transfected with miR‐181b mimics had decreased expression of TLR4, along with the decrease of mitotic indexes and Brdu labelling indexes. However, HEKs transfected with miR‐181b inhibitors showed increased TLR4 expression, mitotic indexes and Brdu labelling indexes. HEKs transfected with both miR‐181b inhibitors and siTLR4 had decreased mitotic indexes and Brdu labelling indexes. These results indicate that miR‐181b can negatively regulate the proliferation of HEKs in psoriasis by targeting TLR4.

miR-197: A novel biomarker for cancers

microRNAs (miRNAs) are small noncoding RNAs that could regulate post-transcription level through binding to 3' untranslated region (3'UTR) of target messenger RNAs (mRNAs), which were reported to be related with the incidence and development of diverse neoplasms. Among them, miR-197 was confirmed to play a vital role of oncogene or anti-oncogene in different cancers via targeting key tumorigenic or tumor-suppressive genes. Additionally, miR-197 had extensively been studied in carcinogenesis progression of cancers through various mechanisms, including apoptosis, proliferation, angiogenesis, metastasis, drug resistance and tumor suppressor, and also played a role in prognosis of cancers. In this review, we summarized the roles of miR-197 in cancers and considered it as a potentially novel biomarker for different cancers, offering an alternatively secure and effective tool in molecular targeting cancer treatment.

MicroRNAs: New regulators of IL-22

Interleukin-22 (IL-22) is a cytokine that belongs to the IL-10 family of interleukins. It can be produced by T helper 22 (Th22) cells, T helper 1 (Th1) cells, T helper 17 (Th17) cells, natural killer 22 (NK22) cells, natural killer T (NKT) cells, innate lymphoid cells (ILCs), and γδ T cells. IL-22 acts via binding to a heterodimeric transmembrane receptor complex that consists of IL-22R1 and IL-10R2 and mainly contributes to the tissue repair and host defense. Transcription factors such as retinoid orphan receptor γt (RORγt) and signal transducer and activator of transcription 3 (STAT3), have been reported to play important roles in regulation of IL-22 expression. Recently, it has been demonstrated in several studies that microRNAs (miRNAs) potently regulate expression of interleukins, including production of IL-22. Here, we review current knowledge about regulators of IL-22 expression with a particular emphasis on the role of miRNAs.

Attenuated Airway Epithelial Cell Interleukin-22R1 Expression in the Infant Nonhuman Primate Lung

Respiratory tract infections are a leading cause of morbidity and mortality in children under 5 years of age. Increased susceptibility to infection is associated with deficiencies in immunity during early childhood. Airway epithelium represents the first line of mucosal defense against inhaled pathogens. However, little is known about epithelial immune mechanisms in the maturing lung. IL-22 and its receptor IL-22R1 are important in host defense and repair of epithelial barriers. The objective of this study was to determine whether a quantitative difference in IL-22R1 exists between infant and adult airways using the rhesus macaque monkey as a model of childhood lung development. Immunofluorescence staining of tracheal tissue revealed minimal expression of IL-22R1 in epithelium at 1 month of age, with a progressive increase in fluorescence-positive basal cells through 1 year of age. Western blot analysis of tracheal lysates confirmed significant age-dependent differences in IL-22R1 protein content. Further, primary tracheobronchial epithelial cell cultures established from infant and adult monkeys showed differential IL-22R1 mRNA and protein expression in vitro. To begin to assess the regulation of age-dependent IL-22R1 expression in airway epithelium, the effect of histone deacetylase and DNA methyltransferase inhibitors was evaluated. IL-22R1 mRNA in adult cultures was not altered by 5-aza-2'-deoxycytidine or trichostatin A. IL-22R1 mRNA in infant cultures showed no change with 5-aza-2'-deoxycytidine but was significantly increased after trichostatin A treatment; however, IL-22R1 protein did not increase concurrently. These data suggest that IL-22R1 in airway epithelium is regulated, in part, by epigenetic mechanisms that are dependent on chronologic age.

Mechanisms of interleukin-22’s beneficial effects in acute pancreatitis

Acute pancreatitis (AP) is a disorder characterized by parenchymal injury of the pancreas controlled by immune cell-mediated inflammation. AP remains a significant challenge in the clinic due to a lack of specific and effective treatment. Knowledge of the complex mechanisms that regulate the inflammatory response in AP is needed for the development of new approaches to treatment, since immune cell-derived inflammatory cytokines have been recognized to play critical roles in the pathogenesis of the disease. Recent studies have shown that interleukin (IL)-22, a cytokine secreted by leukocytes, when applied in the severe animal models of AP, protects against the inflammation-mediated acinar injury. In contrast, in a mild AP model, endogenous IL-22 has been found to be a predominantly anti-inflammatory mediator that inhibits inflammatory cell infiltration via the induction of Reg3 proteins in acinar cells, but does not protect against acinar injury in the early stage of AP. However, constitutively over-expressed IL-22 can prevent the initial acinar injury caused by excessive autophagy through the induction of the anti-autophagic proteins Bcl-2 and Bcl-X_L. Thus IL-22 plays different roles in AP depending on the severity of the AP model. This review focuses on these recently reported findings for the purpose of better understanding IL-22’s regulatory roles in AP which could help to develop a novel therapeutic strategy.

Next-generation sequencing of the basal cell carcinoma miRNome and a description of novel microRNA candidates under neoadjuvant vismodegib therapy: an integrative molecular and surgical case study

BACKGROUND

MicroRNAs (miRNAs) have been identified as key players in posttranscriptional gene regulation and have a significant impact on basal cell carcinoma (BCC) development. The Sonic hedgehog pathway inhibitor vismodegib has been approved for oral therapy of metastatic or advanced BCC. Here, a high-throughput miRNA sequencing analysis was carried out to identify differentially expressed miRNAs and possible novel miRNA candidates in vismodegib-treated BCC tissue. Additionally, we described our surgical experience with neoadjuvant oral vismodegib therapy.

PATIENTS AND METHODS

A punch biopsy (4 mm) from a patient with an extensive cranial BCC under oral vismodegib therapy and a corresponding nonlesional epithelial skin biopsy were harvested. Total RNA was isolated, after which a sequencing cDNA library was prepared, and cluster generation was carried out, which was followed by an ultra-high-throughput miRNA sequencing analysis to indicate the read number of miRNA expression based on miRBase 21. In addition to the identification of differentially expressed miRNAs from RNA sequencing data, additional novel miRNA candidates were determined with a tool for identifying new miRNA sequences (miRDeep2).

RESULTS

We identified 33 up-regulated miRNAs (fold change ≥2) and 39 potentially new miRNA candidates (miRDeep scores 0-43.6). A manual sequence analysis of the miRNA candidates on the genomic locus of chromosome 1 with provisional IDs of chr1_1913 and chr1_421 was further carried out and rated as promising (chr1_1913) and borderline (chr1_421). Histopathology revealed skip lesions in clinically healthy appearing skin at the tumor margins, which were the cause of seven re-excisions by micrographic controlled surgery to achieve tumor-free margins.

CONCLUSION

miRNA sequencing revealed novel miRNA candidates that need to be further confirmed in functional Dicer knockout studies. Clinically, on the basis of our surgical experience described here, neoadjuvant vismodegib therapy in BCC appears to impede histopathologic evaluations with effects on surgical therapy. Thus, larger studies are necessary, but are not preferable at this time if other options are available.

Interleukin-22 activates JAK-STAT3 pathway: Role in liver disease

Interleukin (IL)-22 belongs to the IL-10 family and is secreted mainly by Th22 cells. IL-22 binds to IL-22 receptors which are expressed in special tissues and cells, and activates the signal transducer and activator of transcription 3 (STAT3) signal pathway. IL-22 has a role in liver injury primarily through activating the STAT3 signal pathway. In different types of liver injury, IL-22 protects the liver or aggravates liver injury. This paper will review the role of IL-22 in liver disease in terms of activating the STAT3 signal pathway.

Interleukin-22 in kidney injury and regeneration

Interleukins have become well-known regulators of innate and adaptive immunity-related tissue inflammation. Recently, IL-22 has gained a lot of interest for its unique functions in maintaining and regaining epithelial integrity. IL-22 is exclusively secreted by different immune cell subsets, while IL-22 receptors are mainly expressed by epithelial cells. As the kidney is largely an epithelial organ, the functional role of IL-22 in the kidney deserves to be explored in detail. Here, we briefly summarize the key features of IL-22 biology and review the available data on its expression and functional roles in kidney injury and kidney regeneration. Furthermore, we provide suggestions on how to explore this evolving field in the future.

Role of interleukin-22 in liver diseases

Interleukin (IL)-22, which is discovered by the Dumoutier team during the stimulation of murine BW5147 T lymphoma cells with IL-9, is a member of the IL-10 cytokine family because of the similarity of structure and encoding genes. IL-22 is involved in many inflammatory diseases and autoimmune diseases, such as psoriasis, ulcerative colitis, and systemic lupus erythematosus. Recently it has been found that IL-22 can protect against liver injury and promote hepatocytes proliferation. This paper will make a brief introduction of the role of IL-22 in liver diseases.