Identification of Potential Key Biomarkers and Immune Infiltration in Oral Lichen Planus

Impact of exosomes in oral lichen planus: A review with insights into pathogenesis and biomarkers

Oral Lichen Planus (OLP) presents a significant challenge in diagnosis due to its varied clinical manifestations and the absence of specific biomarkers. Timely and accurate diagnosis is crucial, particularly given its association with oral squamous cell carcinoma (OSCC). This review aims to explore the potential role of exosomes, small extracellular vesicles, in the pathogenesis of OLP and their utility as diagnostic biomarkers. Exosomes facilitate the exchange of information between cells and modulate immune responses by carrying various bioactive molecules such as proteins, lipids, and nucleic acids. In the context of OLP, exosomes derived from affected tissues or immune cells are thought to contribute to disease progression by mediating the transfer of pro-inflammatory molecules, including cytokines like interleukin-6 and tumour necrosis factor-alpha and chemokines such as CCL2, CCL5 and microRNAs such as miR-155, miR-146a, miR-21, and miR-34a, etc. Additionally, the distinct molecular contents of exosomes derived from OLP lesions may accurately represent the pathological changes occurring in these tissues. This suggests the potential of exosomes to be used as non-invasive biomarkers for diagnosing and tracking the progression of the disease. Understanding the immune microenvironment of OLP and the role of exosomes within this context is critical for advancing our knowledge of OLP pathogenesis and identifying new diagnostic and therapeutic strategies. However, challenges remain in identifying and characterising exosomes and their clinical translation. Further research is warranted to address these challenges and fully exploit exosomes' diagnostic and therapeutic potential in OLP and other inflammatory oral diseases.

Identification of the differentially expressed activated memory CD4+ T-cells-related genes and ceRNAs in oral lichen planus

Background

Oral lichen planus (OLP) is a common chronic oral mucosal disease with 1.4 % malignant transformation rate, and its etiology especially immune pathogenesis remains unclear. This study was aimed at investigating the immune cells related molecular underlying the pathophysiology of OLP through bioinformatics analysis.

Methods

The dataset GSE52130 obtained from the Gene Expression Omnibus (GEO) database was conducted a comprehensive analysis in this study. The CIBERSORTx was used for investigating immune cells infiltration. The gene set enrichment analysis (GSEA) and gene ontology (GO) enrichment were performed for exploring the biological functions and gene annotation. The protein-protein interactions (PPI) were constructed by STRING database and visualized by Cytoscape software. The cytohubba plugin was utilized for screening hub genes. The receiver operating characteristic (ROC) was performed for evaluating diagnostic value of hub genes. The miRNAs, lncRNAs and drugs were respectively predicted by NetworkAnalyst, miRTarbase, ENCORI, and DGIdb database.

Results

This study identified 595 differentially expressed genes (DEGs). The GSEA indicated keratinization, innate immune system and biological oxidation were involved in OLP. GO analysis showed extracellular matrix and keratinocyte were mainly enriched. And we found the activated memory CD4+ T cells were lowly infiltrated in OLP. We identified 101 activated memory CD4+ T-cells-related DEGs. Three hub genes (APP, IL1B, TF) were selected. APP and IL1B were significantly up-regulated, whereas TF was down-regulated in OLP. The three hub genes show high diagnostic value in OLP. Additionally, they were involved in MAPK signal, NF-kappaB signal and iron metabolism in OLP. What's more, NEAT1/XIST - miR - 15a - 5p/miR - 155-5p - APP/IL1B signal axis was focused in competing endogenous RNA (ceRNA) network. In addition, 35 drugs were predicted for OLP.

Conclusion

Three activated memory CD4+ T-cells-related DEGs were identified by integrative analysis. It may provide novel insight into the pathogenesis of OLP and suggest potential therapeutic targets for OLP.

Case report: Hypertrophic lichen planus initially misdiagnosed as squamous cell carcinoma

Fewer than 26 case reports describe hypertrophic lichen planus (HLP) misdiagnosed as cutaneous squamous cell carcinoma (cSCC). It can be difficult to distinguish between HLP and cSCC, as these two conditions share many clinical and histopathological characteristics. Patients who are misdiagnosed with cSCC often undergo unnecessary medical and/or surgical interventions before receiving a diagnosis of HLP and improving on HLP-directed therapy. This case series highlights the course of three female patients, referred to a single tertiary institution between 2018 and 2022, who were initially misdiagnosed with cSCC before receiving a diagnosis of HLP. We have emphasized the clinical and histopathological distinguishing features between HLP and cSCC, the pathogenesis of HLP, and current and new HLP-directed therapy. We hope that this case series serves as a reminder to dermatologists, dermatologic surgeons, and dermatopathologists to be aware of this diagnostic challenge.

Idiopathic Subglottic Stenosis Is Associated With More Frequent and Abnormal Squamous Metaplasia

OBJECTIVES

Gain insights into the pathophysiology of idiopathic subglottic stenosis (iSGS) by investigating differences in transcriptome of subglottic mucosal tissue between patients with iSGS and controls, and between tracheal and subglottic tissue within patients.

METHODS

RNA sequencing was conducted on biopsied mucosal samples collected from subglottic and tracheal (in-patient control) regions in iSGS patients, and from subglottis in controls. The gene expression differences were validated on a protein level by (1) staining the tissue samples obtained from a second cohort of patients and controls; and (2) in vitro functional assays using primary subglottic epithelial cells from both iSGS patients and healthy donors.

RESULTS

We found 7 upregulated genes in the subglottic region of iSGS patients relative to both the tracheal mucosa and subglottic region of controls. A gene ontology enrichment analysis found that the epithelial cell differentiation and cornification pathways are significant, involving specifically 3 of the genes: involucrin (IVL), small proline rich protein 1B (SPRR1B), and keratin 16 (KRT16). Involvement of these pathways suggests squamous metaplasia of the epithelium. Histological analyses of epithelium in subglottic mucosal biopsies revealed squamous metaplasia in 41% of the samples from iSGS patients and in 25% from controls. Immunohistochemical evaluation of the samples presented with squamous epithelium revealed increased expression of the protein encoded by SPRR1B, hyperproliferative basal cells, shedding of apical layers, and accompanying lesions in iSGS compared to CTRL. Cultured primary subglottic epithelial cells from iSGS patients had higher proliferation rates compared to healthy donors and squamous metaplastic differentiation formed thinner epithelia with increased expression proteins encoded by INV, SPRR1B, and KRT16, suggesting intrinsic dysfunction of basal cells in iSGS.

CONCLUSIONS

Abnormal squamous differentiation of epithelial cells may contribute to the pathogenesis of iSGS. Patients having metaplastic epithelial phenotype may be sensitive to drugs that reverse it to a normal phenotype.

Immune-mediated oral mucosal pathology: a comprehensive review and update for clinicians. Part I

The oral mucosa can be involved in a wide variety of mucocutaneous conditions that may present primarily in the mouth or affect other cutaneous or mucosal sites. Many of these conditions are immune mediated and typically present as inflammatory mucosal pathology. Patients experiencing such conditions usually seek medical evaluation and treatment due to the associated pain and discomfort and occasionally taste disturbance or dysphagia and the overall deterioration in the oral health-related quality of life. These conditions share some common features and there could be some overlapping in their clinical presentation, which can lead to delays in diagnosis and proper management of patients. Clinicians dealing with such disorders, including dermatologists, need to be aware of the oral manifestations of mucocutaneous conditions, their clinical features, underlying mechanisms, diagnostic approaches, and treatment options, as well as the recent advances in the research on these conditions. This review provides a comprehensive, evidence-based reference for clinicians, with updated insights into a group of immune mediated conditions known to cause oral mucosal pathology. Part one will cover oral lichen planus, erythema multiforme and systemic lupus erythematosus, while part two will cover pemphigus vulgaris and mucous membrane pemphigoid, recurrent aphthous stomatitis, in addition to the less common disorders linear IgA disease, dermatitis herpetiformis and epidermolysis bullosa.

CD8 + T-cell marker genes reveal different immune subtypes of oral lichen planus by integrating single-cell RNA-seq and bulk RNA-sequencing

BACKGROUND

Oral lichen planus (OLP) is a local autoimmune disease induced by T-cell dysfunction that frequently affects middle-aged or elderly people, with a higher prevalence in women. CD8 + T cells, also known as killer T cells, play an important role in the progression and persistence of OLP. In order to identify different OLP subtypes associated with CD8 + T cell pathogenesis, consensus clustering was used.

METHODS

In this study, we preprocessed and downscaled the OLP single-cell dataset GSE211630 cohort downloaded from Gene Expression Omnibus (GEO) to finally obtain the marker genes of CD8 + T cells. Based on the expression of marker genes, we classified OLP patients into CMGs subtypes using unsupervised clustering analysis. The gene expression profiles were analyzed by WGCNA using the "WGCNA" R package based on the clinical disease traits and typing results, and 108 CD8 + T-cell related OLP pathogenicity-related genes were obtained from the intersection. Patients were once again classified into gene subtypes based on intersection gene expression using unsupervised clustering analysis.

RESULTS

After obtaining the intersecting genes of CD8 + T cells related to pathogenesis, OLP patients can be precisely classified into two different subtypes based on unsupervised clustering analysis, and subtype B has better immune infiltration results, providing clinicians with a reference for personalized treatment.

CONCLUSIONS

Classification of OLP into different subtypes improve our current understanding of the underlying pathogenesis of OLP and provides new insights for future studies.

Comprehensive Insight into Lichen Planus Immunopathogenesis

Lichen planus is a chronic disease affecting the skin, appendages, and mucous membranes. A cutaneous lichen planus is a rare disease occurring in less than 1% of the general population, while oral illness is up to five times more prevalent; still, both forms equally impair the patient's quality of life. The etiology of lichen planus is not entirely understood. Yet, immune-mediated mechanisms have been recognized since environmental factors such as hepatitis virus infection, mechanical trauma, psychological stress, or microbiome changes can trigger the disease in genetically susceptible individuals. According to current understanding, lichen planus immunopathogenesis is caused by cell-mediated cytotoxicity, particularly cytotoxic T lymphocytes, whose activity is further influenced by Th1 and IL-23/Th-17 axis. However, other immunocytes and inflammatory pathways complement these mechanisms. This paper presents a comprehensive insight into the actual knowledge about lichen planus, with the causal genetic and environmental factors being discussed, the immunopathogenesis described, and the principal effectors of its inflammatory circuits identified.