Skin-Expressing lncRNAs in Inflammatory Responses

Evaluating dermal toxicity of the flame retardant aluminum diethylphosphinate by in silico-in vitro testing strategy

Flame retardants (FRs) are a group of chemicals used in different products to improve fire safety; however, many of them negatively impact human health, encouraging the use of safer alternatives. The aluminum diethylphosphinate (AlPi) is one of the potential alternatives to harmful FRs; however, close data gaps on human toxicity and enhanced mechanistic understanding are still needed. This study evaluated the dermal toxicity potential of AlPi using in silico models (OECD QSAR Toolbox, Toxtree) and a multi-biomarkers approach with human keratinocyte models (HaCaT cell line and reconstructed human epidermis (RHE) model). Our findings revealed no significant increases in reactive oxygen species (ROS, H2DCFDA) or pro-inflammatory cytokines (IL-6, IL-8, IL-10, IL-1β, IL12p70, TNF) in HaCaT cells exposed to AlPi at non-cytotoxic concentrations (30, 60, 120 μg/ml). This suggests that AlPi does not induce oxidative stress or inflammatory responses in the skin. Additionally, in silico predictions and in vitro assays (HaCaT - IL-6; OECD TG 439 with SkinVitro-RHE) did not classify AlPi as a skin sensitizer or skin irritant. Regarding changes in DNA, AlPi-exposed HaCaT cells did not show significant levels of γ-H2AX; however, this FR increased the level of 5-hydroxymethylcytosine (5-hmC) and TET1 expression, which is a gene involved in the regulation of the DNA methylation. In summary, most biomarker responses indicated that AlPi poses minimal toxic effects on the skin; however, further research is needed to understand better the biological consequences of its effect on DNA methylation.

The role of LINC00114 in atopic dermatitis: modulating inflammation and epidermal barrier dysfunction

Atopic dermatitis (AD) is a chronic inflammatory skin disorder characterized by a dysregulated immune response and impaired epidermal barrier function. Long non-coding RNAs (lncRNAs) have emerged as critical regulators of gene expression in various diseases, yet their specific roles in AD remain poorly understood. This study investigates the role of LINC00114, an lncRNA identified as significantly upregulated in lesional skin of AD patients. Using RNA sequencing, quantitative real-time PCR, and in vitro experiments, we demonstrate that LINC00114 is induced by Th2 cytokines IL-4 and IL-13, correlating with clinical severity scores. Notably, the observed 2-3 fold changes in LINC00114 expression indicate a substantial biological impact; as such alterations can significantly influence inflammatory pathways and epidermal barrier integrity. Mechanistically, LINC00114 functions as a molecular sponge for miR-128, inhibiting its regulatory effects on pro-inflammatory targets. Furthermore, LINC00114 enhances the JAK/STAT signaling pathway, promoting Th2-driven inflammation. Our findings also reveal that LINC00114 impairs epidermal barrier function by downregulating key proteins such as filaggrin and involucrin. In a murine model of AD, targeting LINC00114 with siRNA significantly reduced skin inflammation and improved barrier integrity. These results highlight LINC00114 as a novel therapeutic target for AD, offering potential avenues for more effective treatments aimed at restoring immune balance and skin barrier function.

Molecular Mechanisms and Therapeutic Implications of Long Non-coding RNAs in Cutaneous Biology and Disease

Human skin is the largest organ of the human body and accounts for approximately fifteen percent of the total bodyweight. Its main physiological role is to protect the body against a wide range of environmental factors including pathogens, ultraviolet light, and injury. Importantly, the skin can regenerate and heal upon injury in large part by the differentiation of keratinocytes. Not surprisingly, dysregulation of cutaneous differentiation and self-renewal can result in a variety of skin-related pathologies, including autoimmune disease and cancer. Increasing evidence supports the premise that long non-coding RNAs (lncRNAs) act as critical mediators of gene expression and regulate important biological processes within the skin. Notably, dysregulation of lncRNAs has been shown to influence diverse physiological and pathological consequences. More recently, numerous reports have revealed new mechanistic insight on the role that lncRNAs play in skin homeostasis as well as their contribution to the pathogenesis of skin-related disorders. Here, we review the biological functions of cutaneous lncRNAs and their impact on skin homeostasis. We also describe the fundamental roles of lncRNAs in the pathogenesis of skin-related disorders, including fibrotic, autoimmune, and malignant diseases. Lastly, we will highlight how a better understanding of lncRNAs at the molecular level may reveal novel therapeutic approaches for the improvement of cutaneous disorders.

Biological functions and affected signaling pathways by Long Non-Coding RNAs in the immune system

Recently, the various regulative functions of long non-coding RNAs (LncRNAs) have been well determined. Recently, the vital role of LncRNAs as gene regulators has been identified in the immune system, especially in the inflammatory response. All cells of the immune system are governed by a complex and ever-changing gene expression program that is regulated through both transcriptional and post-transcriptional processes. LncRNAs regulate gene expression within the cell nucleus by influencing transcription or through post-transcriptional processes that affect the splicing, stability, or translation of messenger RNAs (mRNAs). Recent studies in immunology have revealed substantial alterations in the expression of lncRNAs during the activation of the innate immune system as well as the development, differentiation, and activation of T cells. These lncRNAs regulate key aspects of immune function, including the manufacturing of inflammatory molecules, cellular distinction, and cell movement. They do this by modulating protein-protein interactions or through base pairing with RNA and DNA. Here we review the current understanding of the mechanism of action of lncRNAs as novel immune-related regulators and their impact on physiological and pathological processes related to the immune system, including autoimmune diseases. We also highlight the emerging pattern of gene expression control in important research areas at the intersection between immunology and lncRNA biology.

The significance of long chain non-coding RNA signature genes in the diagnosis and management of sepsis patients, and the development of a prediction model

Background

Sepsis is a life-threatening organ dysfunction condition produced by dysregulation of the host response to infection. It is now characterized by a high clinical morbidity and mortality rate, endangering patients' lives and health. The purpose of this study was to determine the value of Long chain non-coding RNA (LncRNA) RP3_508I15.21, RP11_295G20.2, and LDLRAD4_AS1 in the diagnosis of adult sepsis patients and to develop a Nomogram prediction model.

Methods

We screened adult sepsis microarray datasets GSE57065 and GSE95233 from the GEO database and performed differentially expressed genes (DEGs), weighted gene co-expression network analysis (WGCNA), and machine learning methods to find the genes by random forest (Random Forest), least absolute shrinkage and selection operator (LASSO), and support vector machine (SVM), respectively, with GSE95233 as the training set and GSE57065 as the validation set. Differentially expressed genes (DEGs), weighted gene co-expression network analysis (WGCNA), boxplot statistical analysis, and ROC analysis by Random Forest, Least Absolute Shrinkage and Selection Operator (LASSO), and Support Vector Machine (SVM) machine learning methods were used to identify characteristic genes and build the Nomogram Prediction model.

Results

GSE95233 yielded a total of 1069 genes, 102 of which were sepsis-related and 22 of which were non-sepsis controls. GSE57065 yielded a total of 899 genes, with 467 up-regulated and 432 down-regulated, including 82 sepsis-related genes and 25 non-sepsis control genes. WGCNA analysis excluded outlier samples, leaving 2,029 genes for relationship analysis between sepsis- and non-sepsis patient-associated LncRNA network representation modules, as well as Wein plots of differential genes versus genes in key modules of weighted co-expression network analysis to analyze gene intersections. Machine Learning found the sepsis-related characteristic LncRNAs RP3-508I15.21, RP11-295G20.2, LDLRAD4-AS1, and CTD-2542L18.1. The datasets GSE95233 and GSE57065 were analyzed using Boxplot against the screened genes listed above, respectively. The p-value between the sepsis and non-sepsis groups was less than 0.05, indicating that anomalies were statistically significant. CTD-2542L18.1 in dataset GSE57065 had an AUC value of 0.638, which was less than 0.7 and did not indicate diagnostic significance, but RP3-508I15.21, RP11-295G20.2, and LDLRAD4-AS1 had AUC values more than 0.7 after ROC analysis. All four sepsis-associated LncRNA ROC analyses in dataset GSE95233 exhibited AUC values more than 0.7, indicating diagnostic significance.

Conclusion

LncRNAs RP3_508I15.21, RP11_295G20.2, and LDLRAD4_AS1 have some utility in the diagnosis and treatment of adult sepsis patients, as well as some reference importance in guiding the diagnosis and treatment of clinical sepsis.

Inhibition of CYP1A1 expression enhances diabetic wound healing by modulating inflammation and oxidative stress in a rat model

OBJECTIVE

Wound therapies utilizing gene delivery to the skin offer considerable promise owing to their localized treatment benefits and straightforward application. This study investigated the impact of skin electroporation of CYP1A1 shRNA lentiviral particles on diabetic wound healing in a streptozotocin (STZ)-induced rat model.

METHODS

Male Sprague Dawley (SD) rats were made diabetic by injecting STZ and subsequently creating foot skin wounds. The rats were randomly divided into four groups: normal, diabetic foot ulcers (DFU), DFU + control shRNA (electroporation of control shRNA lentiviral particles), and DFU + CYP1A1 shRNA (electroporation of CYP1A1 shRNA lentiviral particles). Wound healing progress was monitored at multiple time points (0, 1, 3, 5, 7, 10, 14 days). On day 14, wound tissue specimens were collected for histological examination. Wound samples collected at days 7 and 14 were used for gene expression analysis via qRT-PCR, assessment of CYP1A1 protein levels using western blotting, and evaluation of oxidative stress markers.

RESULTS

Treatment with CYP1A1 shRNA significantly enhanced diabetic wound healing rates compared to untreated controls over the observation period. Histological analysis revealed improved wound characteristics in the CYP1A1 shRNA-treated group, including enhanced epithelial regeneration, reduced inflammation, and increased collagen deposition, indicative of improved tissue repair. Furthermore, suppression of CYP1A1 corresponded with decreased expression levels of pro-inflammatory cytokines (interleukin-1β, tumor necrosis factor-α, and interleukin-6) and diminished oxidative stress markers (malondialdehyde, superoxide dismutase) within wound tissues.

CONCLUSION

Targeted suppression of CYP1A1 represents a promising therapeutic strategy to enhance diabetic wound healing by modulating inflammation and oxidative stress.

Pathogenesis of Inflammation in Skin Disease: From Molecular Mechanisms to Pathology

Many skin diseases begin with inflammatory changes on a molecular level. To develop a more thorough understanding of skin pathology and to identify new targets for therapeutic advancements, molecular mechanisms of inflammation in the context of skin disease should be studied. Current research efforts to better understand skin disease have focused on examining the role of molecular processes at several stages of the inflammatory response such as the dysregulation of innate immunity sensors, disruption of both transcriptional and post-transcriptional regulation, and crosstalk between immune and neuronal processes (neuro-immune crosstalk). This review seeks to summarize recent developments in our understanding of inflammatory processes in skin disease and to highlight opportunities for therapeutic advancements. With a focus on publications within the past 5 years (2019-2024), the databases PubMed and EBSCOhost were used to search for peer-reviewed papers regarding inflammatory molecular mechanisms and skin disease. Several themes of research interest regarding inflammatory processes in skin disease were determined through extensive review and were included based on their relative representation in current research and their focus on therapeutic potential. Several skin diseases such as psoriasis, atopic dermatitis, hidradenitis suppurativa, and scleroderma were described in the paper to demonstrate the widespread influence of inflammation in skin disease.

AK, Shaker OG, El-Tahlawi SM, Sabri A, Yaseen SM. Molecular Signature of miR-34a/NEAT-1/p53 Axis in Mycosis Fungoides

Background

Mycosis fungoides (MF) is a type of cutaneous T-cell lymphoma where red rash exists on the skin. Understanding the role of miRNAs and ncRNAs in p53-response has become an open discussion, as they can regulate p53 or its downstream targets, and ncRNAs themselves.

Objectives

To evaluate the serum levels of NEAT-1, miR-34a, and p53 in MF patients and its relation to healthy controls to indicate whether it has a potential role in the pathogenesis of the disease. Subjects and Methods. This prospective case-control study was carried out on 75 subjects subdivided into two groups, 35 MF patients (stages 1 and II) and 40 matched healthy controls. Their clinical investigations and serum biomarkers (NEAT-1, miR-34a, and p53) were measured.

Results

There were significant elevations in the expression levels of both NEAT-1 (5.10 ± 1.16) and p53 (277.28 ± 62.02) in the serum of MF patients in comparison with controls (1.01 ± 0.031) and (194.29 ± 16.039), respectively, while the level of miR-34a tends to decrease in MF patients (0.24 ± 0.15). There are no significant difference between MF stages and the level of miR-34a, while in NEAT-1 and p53, there are significant differences with p value <0.05 between the stages and the biomarkers. There is a positive correlation between the %BSA and miR-34a and a slightly positive correlation between NEAT-1 and P53 with (r = 0.353, p=0.037) and (r = 0112, p=0.05), respectively. There were also negative correlations between disease duration and NEAT-1 with (r = -0.341, p=0.045) and between B2 microglobulin level and p53 (r = -0.373, p=0.027).

Conclusion

The combination of miR-34a, NEAT-1, and p53 may be considered as potential biomarkers that play an active role in the disease process of MF for helping in its early diagnosis and stage identification as well.

Long noncoding RNA MALAT1 in dermatologic disorders: a comprehensive review

Dermatologic disorders, affecting the integumentary system, involve diverse molecular mechanisms such as cell proliferation, apoptosis, inflammation and immune responses. Long noncoding RNAs, particularly Metastasis-Associated Lung Adenocarcinoma Transcript 1 (MALAT1), are crucial regulators of gene expression. MALAT1 influences inflammatory responses, immune cell function and signaling pathways, impacting various physiological and pathological processes, including dermatologic disorders. Dysregulation of MALAT1 is observed in skin conditions like psoriasis, atopic dermatitis and systemic lupus erythematosus. However, its precise role remains unclear. This review consolidates knowledge on MALAT1's impact on skin biology and pathology, emphasizing its potential diagnostic and therapeutic implications in dermatologic conditions.

The evaluation of skin sensitization potential of the UVCB substance diisopentyl phthalate by in silico and in vitro methods

Diisopentyl phthalate (DiPeP) is primarily used as a plasticizer or additive within the production of polyvinyl chloride (PVC), and has many additional industrial applications. Its metabolites were recently found in urinary samples of pregnant women; thus, this substance is of concern as relates to human exposure. Depending upon the nature of the alcohol used in its synthesis, DiPeP may exist either as a mixture consisting of several branched positional isomers, or as a single defined structure. This article investigates the skin sensitization potential and immunomodulatory effects of DiPeP CAS No. 84777-06-0, which is currently marketed and classified as a UVCB substance, by in silico and in vitro methods. Our findings showed an immunomodulatory effect for DiPeP in LPS-induced THP-1 activation assay (increased CD54 expression). In silico predictions using QSAR TOOLBOX 4.5, ToxTree, and VEGA did not identify DiPeP, in the form of a discrete compound, as a skin sensitizer. The keratinocyte activation (Key Event 2 (KE2) of the adverse outcome pathway (AOP) for skin sensitization) was evaluated by two different test methods (HaCaT assay and RHE assay), and results were discordant. While the HaCaT assay showed that DiPeP can activate keratinocytes (increased levels of IL-6, IL-8, IL-1α, and ILA gene expression), in the RHE assay, DiPeP slightly increased IL-6 release. Although inconclusive for KE2, the role of DiPeP in KE3 (dendritic cell activation) was demonstrated by the increased levels of CD54 and IL-8 and TNF-α in THP-1 cells (THP-1 activation assay). Altogether, findings were inconclusive regarding the skin sensitization potential of the UVCB DiPeP-disagreeing with the results of DiPeP in the form of discrete compound (skin sensitizer by the LLNA assay). Additional studies are needed to elucidate the differences between DiPeP isomer forms, and to better understand the applicability domains of non-animal methods in identifying skin sensitization hazards of UVCB substances.

Deciphering epigenetic regulations in the inflammatory pathways of atopic dermatitis

Atopic dermatitis, commonly referred to as atopic eczema, is a persistent inflammatory skin disorder that predominantly manifests in children but may endure into adulthood. Its clinical management poses challenges due to the absence of a definitive cure, and its prevalence varies across ethnicities, genders, and geographic locations. The epigenetic landscape of AD includes changes in DNA methylation, changes in histone acetylation and methylation, and regulation by non-coding RNAs. These changes affect inflammatory and immune mechanisms, and research has identified AD-specific variations in DNA methylation, particularly in the affected epidermis. Histone modifications, including acetylation, have been associated with the disruption of skin barrier function in AD, suggesting the potential therapeutic benefit of histone deacetylase inhibitors such as belinostat. Furthermore, non-coding RNAs, particularly microRNAs and long non-coding RNAs (lncRNAs), have been implicated in modulating various cellular processes central to AD pathogenesis. Therapeutic implications in AD include the potential use of DNA methylation inhibitors and histone deacetylase inhibitors to correct aberrant methylation patterns and modulate gene expression related to immune responses and skin barrier functions. Additionally, the emerging role of lncRNAs suggests the possibility of using small interfering RNAs or antisense oligonucleotides to inhibit lncRNAs and adjust their regulatory impact on gene expression. In conclusion, the importance of epigenetic elements in AD is becoming increasingly clear as studies highlight the contribution of DNA methylation, histone modifications and, control by non-coding RNAs to the onset and progression of the disease. Understanding these epigenetic changes provides valuable insights for developing targeted therapeutic strategies.

A Review of MicroRNAs and lncRNAs in Atherosclerosis as Well as Some Major Inflammatory Conditions Affecting Atherosclerosis

It is generally accepted that atherosclerosis is a chronic inflammatory disease. The link between atherosclerosis and other inflammatory diseases such as psoriasis, type 2 diabetes mellitus (T2DM), and rheumatoid arthritis (RA) via metabolic, inflammatory, and immunoregulatory pathways is well established. The aim of our review was to summarize the associations between selected microRNAs (miRs) and long non-coding RNAs (lncRNAs) and atherosclerosis, psoriasis, T2DM, and RA. We reviewed the role of miR-146a, miR-210, miR-143, miR-223, miR-126, miR-21, miR-155, miR-145, miR-200, miR-133, miR-135, miR-221, miR-424, let-7, lncRNA-H19, lncRNA-MEG3, lncRNA-UCA1, and lncRNA-XIST in atherosclerosis and psoriasis, T2DM, and RA. Extracellular vesicles (EVs) are a method of intracellular signal transduction. Their function depends on surface expression, cargo, and the cell from which they originate. The majority of the studies that investigated lncRNAs and some miRs had relatively small sample sizes, which limits the generalizability of their findings and indicates the need for more research. Based on the studies reviewed, miR-146a, miR-155, miR-145, miR-200, miR-133, and lncRNA-H19 are the most promising potential biomarkers and, possibly, therapeutic targets for atherosclerosis as well as T2DM, RA, and psoriasis.

Deregulated Long Non-Coding RNAs (lncRNA) as Promising Biomarkers in Hidradenitis Suppurativa

Background/Objectives: In recent times, epigenetics alterations in Hidradenitis suppurativa (HS) have been explored and exploited translationally to guide investigation of new therapeutic approaches. On the other hand, long noncoding RNAs (LncRNAs), main regulators of the epigenetic status of the human genome, have been scarcely investigated, notwithstanding their potential relevance in broad pathogenesis comprehension. Here, we aim to explore the methylation pattern of lncRNAs in HS. Methods: In this case-control study, 24 HS patients and age-, sex- and BMI-matched controls were analyzed to characterize the methylome of lncRNA genes in peripheral blood cells. Gene ontology analysis (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, protein-protein interaction (PPI) network, and MCODE analysis were performed. Results: A set of fifteen lncRNA genes exhibited significantly differential methylation patterns, with ten of them showing hypomethylation and five displaying hypermethylation at specific CpG sites. The hypomethylated lncRNA genes were DLEU2, MESTIT1, CASC2, TUG1, KCNQ1DN, PSORS1C3, PCA3, DSCR8, RFPL1S, and PVT1, while the hypermethylated ones were HAR1A, FAM66B, SNHG9, HCG9, and HCP5. These lncRNA genes have been linked to various important biological processes, including cell proliferation, apoptosis, inflammation, chronic inflammatory skin diseases, and wound healing. Their altered methylation status suggests potential roles in regulating these processes, and may contribute to HS pathogenesis and healing mechanisms. Conclusions: This study revealed an interesting dysregulation pattern of definite lncRNAs in the methylome which is linked to both the development of HS and its comorbidities. Epigenetically altered lncRNAs genes could represent useful biomarkers, and could help in guiding innovative treatment strategies.

RNA-Based Antipsoriatic Gene Therapy: An Updated Review Focusing on Evidence from Animal Models

Psoriasis presents as a complex genetic skin disorder, characterized by the interaction between infiltrated immune cells and keratinocytes. Substantial progress has been made in understanding the molecular mechanisms of both coding and non-coding genes, which has positively impacted clinical treatment approaches. Despite extensive research into the genetic aspects of psoriasis pathogenesis, fully grasping its epigenetic component remains a challenging endeavor. In response to the pressing demand for innovative treatments to alleviate inflammatory skin disorders, various novel strategies are under consideration. These include gene therapy employing antisense nucleotides, silencing RNA complexes, stem cell therapy, and antibody-based therapy. There is a pressing requirement for a psoriasis-like animal model that replicates human psoriasis to facilitate early preclinical evaluations of these novel treatments. The authors conduct a comprehensive review of various gene therapy in different psoriasis-like animal models utilized in psoriasis research. The animals included in the list underwent skin treatments such as imiquimod application, as well as genetic and biologic injections, and the results of these interventions are detailed. Animal models play a crucial role in translating drug discoveries from the laboratory to clinical practice, and these models aid in improving the reproducibility and clinical applicability of preclinical data. Numerous animal models with characteristics similar to those of human psoriasis have proven to be useful in understanding the development of psoriasis. In this review, the article focuses on RNA-based gene therapy exploration in different types of psoriasis-like animal models to improve the treatment of psoriasis.

Large-scale functional inference for skin-expressing lncRNAs using expression and sequence information

Long noncoding RNAs (lncRNAs) regulate the expression of protein-coding genes and have been shown to play important roles in inflammatory skin diseases. However, we still have limited understanding of the functional impact of lncRNAs in skin, partly due to their tissue specificity and lower expression levels compared with protein-coding genes. We compiled a comprehensive list of 18,517 lncRNAs from different sources and studied their expression profiles in 834 RNA-Seq samples from multiple inflammatory skin conditions and cytokine-stimulated keratinocytes. Applying a balanced random forest to predict involvement in biological functions, we achieved a median AUROC of 0.79 in 10-fold cross-validation, identifying significant DNA binding domains (DBDs) for 39 lncRNAs. G18244, a skin-expressing lncRNA predicted for IL-4/IL-13 signaling in keratinocytes, was highly correlated in expression with F13A1, a protein-coding gene involved in macrophage regulation, and we further identified a significant DBD in F13A1 for G18244. Reflecting clinical implications, AC090198.1 (predicted for IL-17 pathway) and AC005332.6 (predicted for IFN-γ pathway) had significant negative correlation with the SCORAD metric for atopic dermatitis. We also utilized single-cell RNA and spatial sequencing data to validate cell type specificity. Our research demonstrates lncRNAs have important immunological roles and can help prioritize their impact on inflammatory skin diseases.

Genome-Wide Differential Transcription of Long Noncoding RNAs in Psoriatic Skin

Long noncoding RNAs (lncRNAs) may contribute to the formation of psoriatic lesions. The present study's objective was to identify long lncRNA genes that are differentially expressed in patient samples of psoriasis through computational analysis techniques. By using previously published RNA sequencing data from psoriatic and healthy patients (n = 324), we analysed the differential expression of lncRNAs to determine transcripts of heightened expression. We computationally screened lncRNA transcripts as annotated by GENCODE across the human genome and compared transcription in psoriatic and healthy samples from two separate studies. We observed 54 differentially expressed genes as seen in two independent datasets collected from psoriasis and healthy patients. We also identified the differential expression of LINC01215 and LINC1206 associated with the cell cycle pathway and psoriasis pathogenesis. SH3PXD2A-AS1 was identified as a participant in the STAT3/SH3PXD2A-AS1/miR-125b/STAT3 positive feedback loop. Both the SH3PXD2A-AS1 and CERNA2 genes have already been recognised as part of the IFN-γ signalling pathway regulation. Additionally, EPHA1-AS1, CYP4Z2P and SNHG12 gene upregulation have all been previously linked to inflammatory skin diseases. Differential expression of various lncRNAs affects the pathogenesis of psoriasis. Further characterisation of lncRNAs and their functions are important for developing our understanding of psoriasis.

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

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

ASXL3 gene mutations inhibit cell proliferation and promote cell apoptosis in mouse cardiomyocytes by upregulating lncRNA NONMMUT063967.2

Congenital heart disease (CHD) is a serious condition with unknown etiology. In a recent study, a compound heterozygous mutation (c.3526C > T [p.Arg1176Trp] and c.4643A > G [p.Asp1548Gly]) in the ASXL3 gene was identified, which is associated with CHD. This mutation was overexpressed in HL-1 mouse cardiomyocyte cells, leading to increased cell apoptosis and decreased cell proliferation. However, whether this effect is mediated by long noncoding RNAs (lncRNAs) is yet to be determined. We identified the differences among lncRNA and mRNA profiles in mouse heart tissues using sequencing to explore this issue. We detected HL-1 cell proliferation and apoptosis through CCK8 and flow cytometry. Fgfr2, lncRNA, and Ras/ERK signaling pathway expressions were evaluated using quantitative real time polymerase chain reaction (qRT-PCR) and western blot (WB) assays. We also conducted functional investigations by silencing lncRNA NONMMUT063967.2. The sequencing revealed significant changes in lncRNA and mRNA profiles, with the expression of lncRNA NONMMUT063967.2 being significantly promoted in the ASXL3 gene mutations group (MT) while the expression of Fgfr2 being downregulated. The in vitro experiments showed that ASXL3 gene mutations inhibited the proliferation of cardiomyocytes and accelerated cell apoptosis by promoting the expression of lncRNAs (NONMMUT063967.2, NONMMUT063918.2, and NONMMUT063891.2), suppressing the formation of FGFR2 transcripts, and inhibiting the Ras/ERK signaling pathway. The decrease in FGFR2 had the same effect on the Ras/ERK signaling pathway, proliferation, and apoptosis in mouse cardiomyocytes as ASXL3 mutations. Further mechanistic studies revealed that suppression of lncRNA NONMMUT063967.2 and overexpression of FGFR2 reversed the effects of the ASXL3 mutations on the Ras/ERK signaling pathway, proliferation, and apoptosis in mouse cardiomyocytes. Therefore, ASXL3 mutation decreases FGFR2 expression by upregulating lncRNA NONMMUT063967.2, inhibiting cell proliferation and promoting cell apoptosis in mouse cardiomyocytes.

Pseudogenes in Cancer: State of the Art

Pseudogenes are duplicates of protein-coding genes that have accumulated multiple detrimental alterations, rendering them unable to produce the protein they encode. Initially disregarded as "junk DNA" due to their perceived lack of functionality, research on their biological roles has been hindered by this assumption. Nevertheless, recent focus has shifted towards these molecules due to their abnormal expression in cancer phenotypes. In this review, our objective is to provide a thorough overview of the current understanding of pseudogene formation, the mechanisms governing their expression, and the roles they may play in promoting tumorigenesis.

An integrated in silico-in vitro investigation to assess the skin sensitization potential of 4-Octylphenol

One of the major challenges in chemical toxicity testing is the possibility to protect human health against adverse effects with non-animal methods. In this paper, 4-Octylphenol (OP) was tested for skin sensitization and immunomodulatory effects using an integrated in silico-in vitro test approach. In silico tools (QSAR TOOLBOX 4.5, ToxTree and VEGA) were used together with several in vitro tests including HaCaT cells (quantification of IL-6; IL-8; IL-1α and IL-18 by ELISA and expression of genes TNF, IL1A, IL6 and IL8 by RT- qPCR), RHE model (quantification of IL-6; IL-8; IL-1α and IL-18 by ELISA) and THP-1 activation assay (CD86/CD54 expression and IL-8 release). Additionally, the immunomodulatory effect of OP was investigated using lncRNAs MALAT1 and NEAT1 expression and LPS-induced THP-1 activation (CD86/CD54 expression and IL-8 release). The in silico tools predicted OP as a sensitizer. In vitro tests are also concordant with the in silico prediction. OP increased IL-6 expression (HaCaT cells); IL-18 and IL-8 expressions (RHE model). An irritant potential was also shown by a great expression of IL-1α (RHE model); and increased expression of CD54 marker and IL-8 in THP-1 cells. Immunomodulatory effects of OP were demonstrated by the downregulation of NEAT1, MALAT1 (epigenetic markers), IL6 and IL8; and an increase in LPS-induced CD54 and IL-8 expressions. Overall, results indicate that OP is a skin sensitizer, being positive in three key events of the AOP for skin sensitization, also showing immunomodulatory effects.

Morinda officinalis extract exhibits protective effects against atopic dermatitis by regulating the MALAT1/miR-590-5p/CCR7 axis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a genetic predisposition, and the traditional Chinese medicine Morinda officinalis and its roots are characterized with anti-inflammatory effects and have been used for the treatment of various disease. However, it is still largely unknown whether Morinda officinalis extract (MOE) can be used for the treatment of AD.

OBJECTIVES

In our study we aimed to determine whether MOE could ameliorate 2,4-dinitrochlorobenzene (DNCB)-induced AD and elucidate molecular mechanisms.

METHODS

We established an AD mouse model by using DNCB. Skin pathological analysis and ELISA assay were used to detect the effect of MOE on the inflammation of AD model mouse skin and the expression changes of inflammatory factors, and further functional verification was performed in TNF-α/IFN-γ-induced HaCaT cells.

RESULTS

Our in vivo experiments confirmed that MOE remarkably reduced DNCB-induced AD lesions and symptoms, such as epidermal and dermal thickness and mast cell infiltration and inflammatory cytokines secretion in the mice models. In addition, the underlying mechanisms by which MOE ameliorated AD had been uncovered, and we verified that MOE inhibited MALAT1 expression in AD, resulting in attenuated expression of C-C chemokine receptor type 7 (CCR7) regulated by MALAT1-sponge miR-590-5p in a competing endogenous RNA (ceRNA) mechanisms-dependent manner, thereby inhibiting TNF-α/IFN-γ-induced cellular proliferation and inflammation.