Salivary cytokine profile in patients with oral lichen planus

Diagnostic value of 8-OHdG, 8-iso-PGF2α and TNF-α levels in blood for early carcinogenesis of erosive oral lichen planus

BACKGROUND

Oral cancer has a high worldwide incidence and mortality rate showing an upward trend year by year, predominantly occurring in emerging countries. Oral squamous cell carcinoma (OSCC) is one of the main types of oral cancer, accounting for more than 90% of all cases in oral cancer.

OBJECTIVE

To evaluate the diagnostic value of 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-iso-Prostaglandin F2alpha (8-iso-PGF2α) and tumor necrosis factor (TNF)-α as biomarkers in the early carcinogenesis of erosive oral lichen planus (EOLP) by measuring their levels in the blood of patients with EOLP and oral squamous cell carcinoma (OSCC).

METHODS

A total of 69 patients were enrolled in this case-control study [including an OSCC group (n= 23), an EOLP group (n= 23), and an age- and gender-matched healthy control group (n= 23)]. Blood levels of 8-OHdG, 8-iso-PGF2α and TNF-α were measured using enzyme-linked immunosorbent assay (ELISA). Statistical differences in these indicators among the three groups were analyzed.

RESULTS

Plasma levels of 8-OHdG and 8-iso-PGF2α in the OSCC group were significantly higher than those in both the EOLP group and the control group (all P< 0.05); no significant statistical difference was found between the EOLP group and the control group. Serum levels of TNF-α in both the OSCC and EOLP groups were elevated compared with the control group, showing significant differences among all three groups (all P< 0.05). Receiver operating characteristic (ROC) curves revealed that plasma 8-OHdG and 8-iso-PGF2α levels and serum TNF-α levels had diagnostic effects on early carcinogenesis in EOLP patients. When these indicators were combined for diagnosis, the diagnostic effect was enhanced, with an area under the ROC curve (AUC) values of 0.819.

CONCLUSION

8-OHdG, 8-iso-PGF2α and TNF-α may serve as biological indicators for monitoring the early carcinogenesis of EOLP, and the diagnostic effect was augmented when these indicators were combined.

A multi-center cross-sectional study of 1495 Chinese oral lichen planus patients

OBJECTIVE

To explore the clinical epidemiological characteristics of oral lichen planus (OLP) and risk factors for erosive/ulcerative OLP.

MATERIALS AND METHODS

Patients diagnosed with OLP from 11 different hospitals were included in the study. Descriptive statistical methods were used to explore the clinical epidemiological characteristics and logistic regression, sensitivity analysis, and subgroup analysis were utilized to explore the risk factors for erosive/ulcerative OLP.

RESULTS

The average age of patients was 49.2 ± 13.3 years, and 61.4% of the patients were women. The ratios of patients with reticular, hyperemic/erythematous, and erosive/ulcerative lesions were 47.9%, 27.8%, and 24.2%, respectively. Analysis of risk factors for erosive/ulcerative OLP identified the following variables: age, course of disease of 12 months or more, II°-III° dental calculus, hypertension, diabetes, and heart disease, as well as regions of habitation. Subgroup analysis showed significant differences in risk factors for erosive/ulcerative OLP in patients with and without risk behaviors.

CONCLUSION

The clinical epidemiological characteristics of patients with OLP in the Chinese population in this study are basically consistent with existing reports in developed countries. And we identified clinical characteristics associated with erosive/ulcerative OLP through clinical epidemiological analysis.

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.

Upregulation of psoriasin/S100A7 correlates with clinical severity in patients with oral lichen planus

OBJECTIVES

The aim of this study was to: (1) investigate the expression patterns of antimicrobial peptides (AMPs), specifically psoriasin (S100A7) and calgranulin A and B (S100A8/A9), in patients with oral lichen planus (OLP) compared to healthy individuals; (2) evaluate the oral health-related quality of life (OHrQoL) in OLP patients versus healthy controls; (3) investigate the impact of clinical severity of OLP on OHrQoL; and (4) assess the influence of AMP expression on clinical severity and OHrQoL in OLP patients.

MATERIALS AND METHODS

Oral mucosal biopsies (n = 38) were collected from healthy individuals (n = 17) and patients with OLP (n = 21). Levels of AMPs (S100A7, S100A8, S100A9) and pro-inflammatory cytokines interleukin-8 (IL-8) and tumor necrosis factor alpha (TNFα) were assessed by RT-qPCR. AMP protein localization was identified by indirect immunofluorescence analysis. OHrQoL was assessed using the OHIP-G14 questionnaire, and clinical severity was evaluated with the Oral Disease Severity Score (ODSS). Correlations between OLP manifestation, OHrQoL, and AMP expression were evaluated.

RESULTS

(1) S100A7 (p < 0.001), IL-8 (p < 0.001), and TNFα (p < 0.001) mRNA levels were significantly upregulated in OLP tissue compared to healthy tissue, while S100A8 (p < 0.001) and S100A9 (p < 0.001) mRNA levels were downregulated. Immunofluorescence staining revealed an enhanced expression of S100A7 and decreased protein expression of S100A9 in OLP tissue. (2) OLP patients (9.58 ± 8.32) reported significantly higher OHIP-G14 scores compared to healthy individuals (0.67 ± 0.87; p < 0.001), particularly in the categories "physical pain" (p < 0.001) and "psychological discomfort" (p = 0.025). (3,4) Clinical severity (25.21 ± 9.77) of OLP correlated positively with OHrQoL (ρ = 0.497) and psoriasin expression (ρ = 0.402).

CONCLUSIONS

This study demonstrated differential expression patterns of AMPs in OLP and highlighted the correlation between the clinical manifestation of OLP and OHrQoL. Further research approaches should address the role of psoriasin in the risk of malignant transformation of OLP.

CLINICAL RELEVANCE

Psoriasin is a putative biomarker to monitor disease severity including malignant transformation of OLP lesions. OHIP-G14 scores can be useful to monitor OHrQoL in OLP patients.

Oral mucosal changes in tight junction proteins in patients with oral lichen planus

OBJECTIVE

This study aimed to investigate the expression of tight junction, its distribution pattern in oral lichen planus samples and its potential association with the severity of oral lichen planus.

MATERIALS AND METHODS

Cross-sectional study designs were conducted. Transcriptome sequencing was conducted using oral mucosal tissues from 22 patients with oral lichen planus and 11 healthy controls. Immunohistochemistry and quantitative reverse transcription PCR were performed to verify the expression of claudin-1, claudin-4, occludin and zonula occludens-1 in oral mucosal tissues from another 30 patients with oral lichen planus and 26 healthy controls. The relationship between tight junction protein expression and oral lichen planus severity was explored using correlation analysis.

RESULTS

5603 and 2475 differentially expressed genes were upregulated and downregulated respectively, in oral lichen planus tissues. KEGG analysis showed that tight junctions including CLDN1, CLDN4, OCLN and TJP1 were downregulated in oral lichen planus. Claudin-1, claudin-4, occludin and zonula occludens-1 expression was verified to be significantly lower in oral lichen planus. Furthermore, correlation analyses showed that decreased occludin expression was positively related to oral lichen planus severity.

CONCLUSION

Decreased expression of TJ barrier proteins may be associated with the development of oral lichen planus.

[Detection of molecular affecting sensitivity to local glucocorticoid therapy in oral lichen planus through transcriptome sequencing]

OBJECTIVE

To detect key genes of local glucocorticoid therapy in oral lichen planus (OLP) through transcriptome sequencing.

METHODS

The study prospectively enrolled 28 symptomatic patients who visitied Department of Oral Mucosa, Peking University Hospital of Stomatology from November 2019 to March 2023. Topical inunction of 0.1 g/L of dexamethasone was applied for 1 min, 3 times daily for 4 weeks. The patients' signs and pain symptoms were recorded and they were classified as effective group and ineffective group according to the treatment outcome. Their mucosa samples were collected before treatment. After isolating total RNA, transcriptome sequencing was performed. The gene expression data obtained by sequencing were analyzed differently using the DESeq2 package in R software, and the Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis was performed on the basis of the hypergeometric distribution algorithm to describe the biological function of differentially expressed genes (DEGs), accordingly detecting sensitivity related molecular affecting therapeutic effect of dexamethasone.

RESULTS

After 4 weeks treatment by topical dexamethasone, 13 cases of the 28 OLP patients responding well with the sign score reducing from 7.0 (4.5, 9.0) to 5.0 (3.0, 6.3), pain score decreasing from 5.0 (2.0, 5.5) to 2.0 (0.0, 3.5), oral health impact profile lessening from 5.0 (3.5, 9.0) to 1.0 (0.0, 5.0) significantly (P<0.01) were classified as effective group and 15 cases with poor response to the drug were sorted as ineffective group. There were no significant differences of demographic and baseline levels of clinical features, especially disease severity between these two groups. A total of 499 DEGs including 274 upregulated and 225 downregulated genes were identified between effective group and ineffective group. KEGG enrichment analysis showed that upregulated genes in effective group compared with ineffective group including CLDN8, CTNNA3, MYL2 and MYLPF were associated with leukocyte transendothelial migration, while downregulated genes were significantly enriched in tumor necrosis factor (TNF), interleukin-17 (IL-17), nuclear factor kappa B (NF-κB) signaling pathways, and cortisol synthesis and secretory.

CONCLUSION

High expressions of CLDN8, CTNNA3, MYL2 and MYLPF genes in patients with oral lichen planus have a good clinical response to topical dexamethasone, while patients with high expression genes of inflammation pathway such as TNF, IL-17, NF-κB and cortisol synthesis and secretion received poor effect.

Predicting the Activity of Oral Lichen Planus with Glycolysis-related Molecules: A Scikit-learn-based Function

OBJECTIVE

Oral lichen planus (OLP) is one of the most common oral mucosa diseases, and is mainly mediated by T lymphocytes. The metabolic reprogramming of activated T cells has been shown to transform from oxidative phosphorylation to aerobic glycolysis. The present study investigated the serum levels of glycolysis-related molecules (lactate dehydrogenase, LDH; pyruvic acid, PA; lactic acid, LAC) in OLP, and the correlation with OLP activity was assessed using the reticular, atrophic and erosive lesion (RAE) scoring system.

METHODS

Univariate and multivariate linear regression functions based on scikit-learn were designed to predict the RAE scores in OLP patients, and the performance of these two machine learning functions was compared.

RESULTS

The results revealed that the serum levels of PA and LAC were upregulated in erosive OLP (EOLP) patients, when compared to healthy volunteers. Furthermore, the LDH and LAC levels were significantly higher in the EOLP group than in the nonerosive OLP (NEOLP) group. All glycolysis-related molecules were positively correlated to the RAE scores. Among these, LAC had a strong correlation. The univariate function that involved the LAC level and the multivariate function that involved all glycolysis-related molecules presented comparable prediction accuracy and stability, but the latter was more time-consuming.

CONCLUSION

It can be concluded that the serum LAC level can be a user-friendly biomarker to monitor the OLP activity, based on the univariate function developed in the present study. The intervention of the glycolytic pathway may provide a potential therapeutic strategy.

Escherichia coli enhances Th17/Treg imbalance via TLR4/NF-κB signaling pathway in oral lichen planus

Oral lichen planus (OLP) is a T-cell-mediated immunoinflammatory disease. Several studies have proposed that Escherichia coli (E. coli) may participate in the progress of OLP. In this study, we examined the functional role of E. coli and its supernatant via toll-like receptor 4 (TLR4)/nuclear factor-kappab (NF-κB) signaling pathway in regulating T helper (Th) 17/ regulatory T (Treg) balance and related cytokines and chemokines profile in OLP immune microenvironment. We discovered that E. coli and supernatant could activate the TLR4/NF-κB signaling pathway in human oral keratinocytes (HOKs) and OLP-derived T cells and increase the expression of interleukin (IL)-6, IL-17, C-C motif chemokine ligand (CCL) 17 and CCL20, thereby increasing the expression of retinoic acid-related orphan receptor (RoRγt) and the proportion of Th17 cells. Furthermore, the co-culture experiment revealed that HOKs treated with E. coli and supernatant increased T cell proliferation and migration, which promoted HOKs apoptosis. TLR4 inhibitor (TAK-242) successfully reversed the effect of E. coli and its supernatant. Consequently, E. coli and supernatant activated the TLR4/NF-κB signaling pathway in HOKs and OLP-derived T cells, leading to increased cytokines and chemokines expression and Th17/Treg imbalance in OLP.

E. coli LPS/TLR4/NF-κB Signaling Pathway Regulates Th17/Treg Balance Mediating Inflammatory Responses in Oral Lichen Planus

Oral lichen planus (OLP) is a chronic inflammatory autoimmune disease mediated by T cells. The imbalance of microflora has potential impacts on the onset and development of OLP, but the mechanism is still unclear. Here, we investigated the effects of Escherichia coli (E. coli) lipopolysaccharide (LPS) simulating the microbial enrichment state of OLP on T cell immune functions in vitro. Effect of E. coli LPS on the viability of T cell using CCK8 assay. After E. coli LPS pretreatment, the expression of the toll-like receptor 4 (TLR4), nuclear factor-kappa B p65 (NF-κB p65), cytokines, retinoic acid-related orphan receptor γt (RORγt), and forkhead box p3 (Foxp3) in the peripheral blood of OLP patients and normal controls (NC) were assessed using quantitative RT-PCR (qRT-PCR), western blot, and enzyme-linked immunosorbent assay (ELISA). Finally, Th17 and Treg cells were detected by flow cytometry. We found that the TLR4/NF-κB pathway was activated and the expression of interleukin (IL)-6 and IL-17 was increased in both groups after E. coli LPS stimulation. CC chemokine ligand (CCL)20 and CC chemokine receptor (CCR)4 expression was increased in OLP after E. coli LPS treatment, while no difference was found in CCR6 and CCL17 expression of both groups. Moreover, E. coli LPS treatment enhanced the proportion of Th17 cells, Th17/Treg ratio, and RORγt/Foxp3 ratio in OLP. In conclusion, E. coli LPS regulated Th17/Treg balance to mediate the inflammatory responses of OLP through the TLR4/NF-κB pathway in vitro, indicating that oral microbiota dysbiosis affected the chronic inflammatory state of OLP.

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.

A review on interleukins (IL10 and IL17) as biomarkers for hepatitis C-associated oral lichen planus

Background

Hepatitis C virus is a viral infection associated with autoimmune disorders. This virus has hepatic and extrahepatic manifestations. One of the extrahepatic manifestations associated with the hepatitis C virus includes oral lichen planus. Oral lichen planus is an autoimmune disorder mainly affecting the tongue and buccal mucosa. It clinically represents grayish-white striae bilaterally on the buccal mucosa. The pathogenesis involves the progression of the hepatitis C virus, and oral lichen planus affects T lymphocytes. Specific proteins and cytokines activate these T lymphocytes, which act as biomarkers to detect certain diseases. Interleukin 10 is an anti-inflammatory cytokine, whereas interleukin 17 is a pro-inflammatory cytokine. These cytokines have a pathophysiological role and act as biomarkers for many diseases. Therefore, this review article aims to establish the role of interleukin 10 and interleukin 17 as biomarkers for hepatitis C-associated oral lichen planus.

Conclusion

Hepatitis C virus is an infectious disease that can lead to liver cirrhosis, and oral lichen planus is a premalignant lesion that can lead to oral carcinoma. As interleukin 10 lessens the immune pathologies and interleukin 17 mediates proinflammatory response, therefore, these biomarkers have a role in progression of these diseases.

Oral Microbiome Research on Oral Lichen Planus: Current Findings and Perspectives

Simple Summary

Oral lichen planus is a disease of the oral mucosa, which frequently affects women aged 40 years or older. Though the T cell-mediated immune response is involved in the development of oral lichen planus, attempts to identify a microorganism that causes the disease have been unsuccessful. Recent studies on the development of oral lichen planus are focusing on the role of the oral microbiome, which includes oral microbiota and their products, and the host environment. The role of the human microbiome in various diseases has been identified and regulating the microbiome is becoming important in personalized medicine. In this review, we summarized current findings on the role of the oral microbiome in the development of oral lichen planus. The homeostasis of the oral microbiome is disrupted in patients, and functional analysis of oral microbiota and oral mucosa implies that pathways involved in defense against bacterial infection and in the inflammatory response are activated in the oral lichen planus-associated oral microbiome. Though the lack of studies to date makes it difficult to conclude, further studies on the oral microbiome associated with the disease will enable a holistic understanding of the role of the oral microbiome in the development of oral lichen planus and developing a personalized therapy for the disease.

Abstract

Oral lichen planus (OLP) is a chronic inflammatory disease of the oral mucosa with an unknown etiology. The role of oral microbes in the development of OLP has gained researchers’ interest. In this review, we summarized the findings of studies focused on the relationship between OLP and oral microbiome, which includes the composition of oral microbiota, molecules produced by oral microbiota or the host, and the oral environment of the host. According to the studies, the oral microbial community in OLP patients undergoes dysbiosis, and the microbial dysbiosis in OLP patients is more prominent in the buccal mucosa than in the saliva. However, no same microorganisms have been suggested to be associated with OLP in multiple investigations, implying that the functional aspects of the oral microbiota are more important in OLP development than the composition of the oral microbiota. According to studies on host factors that make up the oral environment, signal pathways involved in cellular processes, such as keratinization, inflammation, and T cell responses are triggered in OLP. Studies on the functional aspects of the oral microbiota, as well as interactions between the host and the oral microbiota, are still lacking, and more research is required.