Oral and serum IL-6 levels in oral lichen planus patients

Microbial Profiles in Oral Lichen Planus: Comparisons with Healthy Controls and Erosive vs. Non-Erosive Subtypes

Recent studies have begun exploring the potential involvement of microbiota in the pathogenesis of oral lichen planus (OLP), yet comprehensive investigations remain limited. Hence, this study aimed to compare the microbial profiles in saliva samples obtained from patients with OLP against those from healthy controls (HC), along with a comparison between erosive (E) and non-erosive (NE) OLP patients. Saliva samples were collected from 60 OLP patients (E: n = 25, NE: n = 35) and 30 HC individuals. Analysis revealed no significant differences in alpha diversity, as assessed by the Chao1 and Shannon index, across the three groups. However, Bray-Curtis distance analysis indicated a significant disparity in microbiome composition distribution between HC and E-OLP, as well as HC and NE-OLP groups. The six most abundant phyla observed across the groups were Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Fusobacteria, and Saccharibacteria (TM7). Notably, OLP groups exhibited a higher prevalence of Bacteroidetes. Prevotella emerged as the predominant genus in the OLP groups, while Capnocytophaga showed a relatively higher prevalence in E-OLP compared to NE-OLP. This study's findings indicate a notable difference in microbiota composition between HC and patients with OLP. Additionally, differences in the microbiome were identified between the E-OLP and NE-OLP groups. The increase in the proportion of certain bacterial species in the oral microbiome suggests that they may exacerbate the inflammatory response and act as antigens for OLP.

Development of an immune-related diagnostic predictive model for oral lichen planus

Oral lichen planus (OLP) was a chronic inflammatory disease of unknown etiology with a 1.4% chance of progressing to malignancy. However, it has been suggested in several studies that immune system disorders played a dominant role in the onset and progression of OLP. Therefore, this experiment aimed to develop a diagnostic prediction model for OLP based on immunopathogenesis to achieve early diagnosis and treatment and prevent cancer. In this study, 2 publicly available OLP datasets from the gene expression omnibus database were filtered. In the experimental group (GSE52130), the level of immune cell infiltration was assessed using MCPcounter and ssGSEA algorithms. Subsequently, differential expression analysis and gene set enrichment analysis were performed between the OLP and control groups. The resulting differentially expressed genes were intersected with immunologically relevant genes provided on the immunology database and analysis portal database (ImmPort) website to obtain differentially expressed immunologically relevant genes (DEIRGs). Furthermore, the gene ontology and kyoto encyclopedia of genes and genomes analyses were carried out. Finally, protein-protein interaction network and least absolute shrinkage and selection operator regression analyses constructed a model for OLP. Receiver operating characteristic curves for the experimental and validation datasets (GSE38616) were plotted separately to validate the model's credibility. In addition, real-time quantitative PCR experiment was performed to verify the expression level of the diagnostic genes. Immune cell infiltration analysis revealed a more significant degree of inflammatory infiltration in the OLP group compared to the control group. In addition, the gene set enrichment analysis results were mainly associated with keratinization, antibacterial and immune responses, etc. A total of 774 differentially expressed genes was obtained according to the screening criteria, of which 65 were differentially expressed immunologically relevant genes. Ultimately, an immune-related diagnostic prediction model for OLP, which was composed of 5 hub genes (BST2, RNASEL, PI3, DEFB4A, CX3CL1), was identified. The verification results showed that the model has good diagnostic ability. There was a significant correlation between the 5 hub diagnostic biomarkers and immune infiltrating cells. The development of this model gave a novel insight into the early diagnosis of OLP.

Inflammatory cytokines and oral lichen planus: a Mendelian randomization study

Background

Inflammatory cytokines have long been considered closely related to the development of oral lichen planus (OLP), and we further explored the causal relationship between the two by Mendelian randomization (MR) method.

Methods

We performed bidirectional MR analyses by large genome-wide association studies (GWAS). The data included a large-scale OLP dataset, as well as datasets of 41 inflammatory cytokines. All data were obtained from the University of Bristol database, which includes 41 inflammatory cytokines, and the GWAS Catalog database, which includes 91 inflammatory cytokines. OLP data were obtained from the Finngen database, which includes 6411 cases and 405770 healthy controls. We used the inverse variance weighted (IVW) method, MR-Egger method, weighted median method, simple mode method and weighted mode method to analyze the causal relationship between inflammatory cytokines and OLP, and we also combined with sensitivity analysis to further verify the robustness of the results. We performed a meta-analysis of positive or potentially positive results for the same genes to confirm the reliability of the final results.

Results

We primarily used the IVW analysis method, corrected using the Benjamin Hochberg (BH) method. When p<0.00038 (0.05/132), the results are significantly causal; when 0.00038

Conclusion

There is a causal association between OLP and some inflammatory cytokines, which may play an important role in the pathogenesis of OLP and require further attention.

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Key Words

• Mendelian randomization
• immunity
• inflammation
• inflammatory cytokines
• oral lichen planus

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MESH Headings

• Humans
• Cytokines/genetics
• Genome-Wide Association Study
• Lichen Planus, Oral/genetics
• Mendelian Randomization Analysis
• Reproducibility of Results

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Affiliation(s)

Xin Chen Department of Oral and Maxillofacial Surgery, Jiangyin People's Hospital Affiliated to Nantong University, Wuxi, Jiangsu, China
Simin Zhang Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China Department of General Dentistry, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China
Xiao Wu Endodontic Department, School of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China
Yuxi Lei Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China Department of Emergency Room, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China
Bing Lei Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China Department of General Dentistry, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China
Zhibai Zhao Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China Department of General Dentistry, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, China

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Salivary metabolomics in patients with oral lichen planus: a preliminary study based on NMR spectroscopy

OBJECTIVES

The present preliminary study aimed to investigate the salivary metabolic profile in patients with asymptomatic oral lichen planus (OLP) using nuclear magnetic resonance (NMR) spectroscopy.

MATERIAL AND METHODS

Stimulated whole mouth saliva (SWMS) samples were collected from 15 reticular OLP female patients and 15 from age- and sex-matched controls (HCs). A total of 23 metabolites were identified and quantified. Mann-Whitney's U test was used to compare the determined concentration salivary metabolite concentrations between OLP patients and the healthy controls.

RESULTS

The concentration of acetate, methylamine, and pyruvate was elevated, whereas the concentration of tyrosine was decreased in the saliva of OLP patients compared with HCs. To identify a combination of metabolites, multivariate discrimination function analysis (DFA) was conducted. DFA analysis have shown that the most powerful discrimination between the groups was achieved when methylamine and tyrosine were considered as combined biomarkers.

CONCLUSIONS

Salivary tyrosine was of particular interest and a promising finding for the screening of OLP and its progression. Further longitudinal studies are required to establish it as a reliable salivary biomarker in OLP.

CLINICAL RELEVANCE

The salivary metabolic profiling can describe the pathologic characteristics of OLP on non-invasive saliva samples and NMR analysis. Salivary metabolites provide details to considered early detectors and to impact oral health of OLP patients.

Updates on immunological mechanistic insights and targeting of the oral lichen planus microenvironment

Oral lichen planus (OLP) is a chronic immune inflammatory disease that is an oral potentially malignant disorder (OPMD), occurs in the oral mucosa and affects approximately 0.5% to 4% of the general population. There are usually five types of OLP: reticular/papular, plaque-like, atrophic/erythematous, erosive/ulcerative, and bullous. Furthermore, the chance of causing oral squamous cell carcinoma (OSCC) is 1.4%. Although the etiology of OLP is still unknown, accumulating evidence supports that immune dysregulation may play a vital role in the pathogenesis of OLP, especially the massive production of various inflammatory cells and inflammatory mediators. In this review, we focus on the relationship between OLP and its immune microenvironment. We summarize current developments in the immunology of OLP, summarizing functional cell types and crucial cytokines in the OLP immune microenvironment and the underlying mechanisms of key signaling pathways in the OLP immune microenvironment. We highlight the application potential of targeted immune microenvironment therapy for OLP.

Direct immunofluorescence and immune function in patients with oral lichen planus

Background/Purpose

Direct immunofluorescence and immune function and patients with oral lichen planusThe etiology of oral lichen planus (OLP) is unknown, our purpose was to evaluate the diagnostic value of direct immunofluorescence (DIF) and to investigate the immune functions in OLP.

Materials and methods

We enrolled 65 patients with suspected lesions of OLP and 47 controls. In all participants, clinical and serologic testing were conducted. The histopathologic and DIF tests were conducted in 65 patients. The severity of OLP was evaluated by reticular/hyperkeratotic, erosive/erythematous, ulcerative (REU) scoring system.

Results

By hematoxylin and eosin (H&E) staining and DIF examination, 71.2% (42/59) were diagnosed as OLP, 28.8% (17/59) were diagnosed as non-OLP. DIF demonstrated 64.3% positive reactivity with 2 distinct distribution patterns and 8 staining patterns. Compared to the controls, serum IgA in OLP was higher (P < 0.01), and serum CD3+ cells, IgM, IgE, C3 and C4 were lower (P < 0.05). Pearson correlation analysis in OLP revealed correlations between REU score and IgM, IgA of DIF (r = 0.54, P = 0.026; and r = 0.56, P = 0.020, respectively), between serum IgG and IgG of DIF (r = 0.51, P = 0.038), between serum CD4+ and the ratio of CD4+/CD8+, IgM in DIF (r = −0.50, P = 0.048; and r = −0.54, P = 0.031, respectively), between serum CD8+ and IgM, IgA in DIF (r = 0.52, P = 0.038; and r = −0.50, P = 0.047, respectively).

Conclusion

A combination of H&E test and DIF is useful for the diagnosis of OLP. Compared to controls, immune changes happen to patients with OLP. There are significant associations between the OLP lesions and general cellular and humoral immune status, localized humoral immune response.

Probiotics as Potential Biological Immunomodulators in the Management of Oral Lichen Planus: What's New?

Oral lichen planus (OLP) is a T cell-mediated chronic inflammatory disorder with multifactorial aetiology and malignant transformation potential. Despite the treatments so far identified, new tailored and safe specific measures are needed. Recently, human microbiota imbalance has been linked to several immune-mediated diseases, opening new therapeutic perspectives for probiotics; besides their ability to directly interact with the host microbiota, they also display a strain-specific immune-modulatory effect. Thus, this non-systematic review aims to elucidate the molecular pathways underlying probiotic activity, mainly those of Lactobacilli and Bifidobacteria and their metabolites in OLP pathogenesis and malignant transformation, focusing on the most recent in vitro and in vivo research evidence. Findings related to their activity in other immune-mediated diseases are here included, suggesting a probiotic translational use in OLP. Probiotics show immune-modulatory and microbiota-balancing activities; they protect the host from pathogens, hamper an excessive effector T cell response, reduce nuclear factor-kappa B (NF-kB) signalling and basal keratinocytes abnormal apoptosis, shifting the mucosal response towards the production of anti-inflammatory cytokines, thus preventing uncontrolled damage. Therefore, probiotics could be a highly encouraging prevention and immunotherapeutic approach for a safer and more sustainable OLP management.

An association of the MCP-1 and CCR2 gene polymorphisms with oral lichen planus

OBJECTIVE

The purpose of this study was to investigate the frequency of monocyte chemoattractant protein (MCP)-1 CCR2 gene polymorphisms in Turkish patients with oral lichen planus (OLP).

STUDY DESIGN

A cohort of 50 patients with OLP and 142 control participants without OLP were recruited to investigate the frequency of MCP-1 and CCR2 gene polymorphisms. Chi-square and Fisher's exact tests were used. Student t test and analysis of variance were used to compare demographic data between groups.

RESULTS

The MCP AA genotype was less common in the patient group (52%) than in the control group (66.2%; odds ratio [OR] = 0.553; 95% confidence interval [CI], 0.287-1.065; P = .075). The MCP G allele was higher in the patient group (48%) than in the control group (33.8%; OR = 1.808; 95% CI, 0.939-3.479; P = .075). The frequency of the MCP GG genotype was observed to be higher in the patient group (4%) than in the controls (0.7%; OR: 5.875, 95% CI:0.521-66,24; p = 0.106). The CCR2 64I64I genotype was more common in the patient group (6%) than in the control group (2.8%). All results were not statistically significant.

CONCLUSION

We suggest that the G allele of MCP-1 and 64I64I genotype of CCR2 polymorphisms do not pose an increased risk for Turkish patients with OLP to develop oral squamous cell carcinoma.

Salivary Biomarkers and Their Application in the Diagnosis and Monitoring of the Most Common Oral Pathologies

Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner—and the results of its analysis complement clinical and histopathological findings in the diagnosis of multiple diseases. The objective of this review was to offer an update on the contribution of salivary biomarkers to the diagnosis and prognosis of diseases of the oral cavity, including oral lichen planus, periodontitis, Sjögren’s syndrome, oral leukoplakia, peri-implantitis, and medication-related osteonecrosis of the jaw. Salivary biomarkers such as interleukins, growth factors, enzymes, and other biomolecules have proven useful in the diagnosis and follow-up of these diseases, facilitating the early evaluation of malignization risk and the monitoring of disease progression and response to treatment. However, further studies are required to identify new biomarkers and verify their reported role in the diagnosis and/or prognosis of oral diseases.

Oral Complications of Chronic Graft-Versus-Host Disease

The increasing clinical indications for hematopoietic stem cell transplantation (HSCT) and improved clinical care throughout and following HSCT have led to not only long-term survival but also to an increasing incidence and prevalence of graft-versus-host disease (GVHD). Chronic GVHD (cGVHD) affects almost 50% of adult patients post-HSCT, with increasing incidence in pediatric patients as well. Oral cGVHD specifically has a reported prevalence ranging from 45% to 83% in patients who develop cGVHD and is more extensive in adult patients than in children. Oral cGVHD affects patients through clinically significant oral symptoms that may lead to significantly decreased caloric intake, oral infections, and increased health service utilization, and may thus affect overall health and survival. The most commonly used therapy for mucosal involvement of oral cGVHD is topical high-dose and ultra-high potency corticosteroids, and calcineurin inhibitors. This review of oral complications of cGVHD presents the clinical significance of oral cGVHD to HSCT survivors, our current understanding of the pathobiology of oral cGVHD and gaps in this evidence, and the global targeted interdisciplinary clinical research efforts, including the National Institutes of Health Consensus Development Project on Criteria for Clinical Trials in Chronic Graft-versus-Host Disease. Current challenges regarding the management of oral cGVHD and strategies to advance our scientific understanding of this clinically significant chronic oral disease are presented.

Evaluation of serum and salivary interferon-γ levels in patients with oral lichen planus: a systematic review and meta-analysis of case-control studies

OBJECTIVE

Cytokines have regulatory and leading roles in the immunopathogenesis of oral lichen planus (OLP). Here, we present the findings of a meta-analysis that evaluated serum and salivary interferon-γ (IFN-γ) levels in patients with OLP compared with those in controls and the correlation of this cytokine with the progression of OLP.

STUDY DESIGN

Four databases-PubMed, Web of Science, Scopus, and Cochrane Library-were searched, from their start dates to November 2017, for reports in all languages on the effect of OLP on salivary and serum IFN-γ.

RESULTS

Eleven studies were included and analyzed in this meta-analysis. The pooled mean difference (MD) values were estimated to be 3.60 pg/mL (P = .23) and -0.02 pg/mL (P = 1.00) for serum and salivary levels of IFN-γ, respectively, in the patients with OLP compared with controls. The pooled MD values were -2.52 pg/mL (P = .03) and -2.01 pg/mL (P = .20) for serum and salivary IFN-γ levels in the erosive type, respectively, compared with the nonerosive type.

CONCLUSIONS

According to the results of meta-analysis, there was no statistically significant differences in IFN-γ levels between the OLP group and the control group both in serum and salivary levels and also between erosive and nonerosive types of OLP at the salivary level; so this cytokine is not considered to have an important role in the pathogenesis or severity of OLP.

Interleukin-6 levels in the serum and saliva of patients with oral lichen planus compared with healthy controls: a meta-analysis study

Interleukin-6 (IL-6) is a cytokine that contributes to the pathogenesis of oral lichen planus (OLP). The aim of this meta-analysis study is the evaluation of IL-6 levels in the serum and saliva of patients with OLP compared with healthy controls. We searched the studies in 5 databases: PubMed/Medline, Scopus, ScienceDirect, Web of Science, and Cochrane Library, from 1983 to Oct 31, 2016. Eleven studies were analysed for the meta-analysis study. The reviewers independently evaluated the quality of each included study using the Newcastle-Ottawa Quality Assessment Scale (NOS). A random-effects meta-analysis, using Comprehensive Meta-Analysis software version 2.0, was used to reflect the variation in studies. Heterogeneity between estimates was evaluated by the Q and I² statistics and for the Q statistic; heterogeneity was considered for p < 0.1. Eleven studies included 529 OLP patients and 333 healthy controls. The review identified two different biomaterials used for IL-6 assays: saliva and serum. The mean quality score of eleven studies was 7 (high quality). Estimates pooled from 6 studies showed significant high saliva IL-6 levels in OLP patients compared with healthy controls (the standardised difference in means (SDM) = 4.534, 95% CI = 1.915-7.153, p = 0.001). Also, estimates pooled from 7 studies showed significantly high serum IL-6 levels in OLP patients compared with healthy controls (SDM = 1.482, 95% CI = 0.524-2.439, p = 0.002). The higher levels of IL-6 in saliva compared with serum suggest that measurement of this marker in saliva may be more useful than serum for diagnostic and therapeutic aims.

Differential expression of STAT-3 in subtypes of oral lichen planus: a preliminary study

OBJECTIVE

This study aimed to examine the expression of signaling transduction proteins and their possible correlation with different clinical subtypes of oral lichen planus (OLP).

STUDY DESIGN

We examined the immunoexpression and phosphorylation status of 21 signaling transduction proteins of OLP (n = 10) and normal groups (n = 8) using PathScan analysis. Using immunohistochemistry, we detected expression of STAT-3 and p38 MAPK in tissues of OLP (n = 40) and normal controls (n = 10).

RESULTS

PathScan analysis showed that STAT-3 (Ser727) expression in normal control (N), reticular OLP (R-OLP) and erosive OLP (E-OLP) group was gradually elevated (R-OLP vs N, P = .001; E-OLP vs N, P < .001; E-OLP vs R-OLP, P = .002). Immunohistochemistry showed that STAT-3 expression in the epithelium of normal control, reticular OLP and erosive OLP was consistent with PathScan analysis (R-OLP vs N, P < .001; E-OLP vs N, P < .001; E-OLP vs R-OLP, P = .036). Both PathScan (P = .012) and immunohistochemistry (P < .001) showed that, p38 MAPK expression was significantly higher in OLP compared with normal controls. However, a significant difference was not seen between the reticular OLP and erosive OLP groups.

CONCLUSIONS

Our results indicate that STAT-3 may be involved in OLP development and progression and account for different clinical manifestations.

The relationship between levels of salivary and serum interleukin-6 and oral lichen planus: A systematic review and meta-analysis

BACKGROUND

The relationship between levels of salivary and serum interleukin (IL)-6 and oral lichen planus (OLP) is not understood fully. The authors conducted a systematic review and meta-analysis to compare levels of salivary and serum IL-6 among people with OLP and healthy control participants.

METHODS

The authors searched the literature for studies whose investigators had evaluated the relationships between IL-6 and OLP before treatment. The authors used meta-analysis to compare the standardized mean differences (SMD) of the levels of salivary and serum IL-6 between people who had OLP and people who did not have OLP and between patients with erosive OLP and patients with nonerosive OLP.

RESULTS

The results of separate meta-analyses, which included 5 studies each, indicated that the levels of salivary and serum IL-6 were significantly higher among patients with OLP than among healthy control participants (SMD, 2.35; 95% confidence interval [CI], 0.50 to 4.19; P = .01; and SMD, 2.03; 95% CI, 0.74 to 3.33; P = .002; respectively). The results of a meta-analysis of 4 studies indicated that the levels of IL-6 were not significantly different between patients with erosive OLP and patients with nonerosive OLP (SMD, 1.37; 95% CI, -0.26 to 3.00; P = .10). There was significant heterogeneity among the studies (P < .00001).

CONCLUSIONS

Through the results of this meta-analysis, the authors found significant differences in the levels of IL-6 in saliva and serum between patients with OLP and healthy control participants. The authors found no differences in the levels of serum IL-6 between patients with erosive OLP and patients with nonerosive OLP. These results should be considered with caution because there was a high degree of heterogeneity among studies.

PRACTICAL IMPLICATIONS

Levels of IL-6 in saliva and serum may be potential biomarkers for OLP. However, additional research is needed to confirm findings of this meta-analysis.

Identifying the association between interleukin-6 and lichen planus: A meta-analysis

Numerous studies have examined the association between interleukin-6 and the pathogenesis of lichen planus (LP)/oral LP (OLP) in various populations; however, there is a lack of systematic analysis. The aim of the present study was to assess this association more precisely, thus a meta-analysis was performed. Case-control studies, which were published up to December 2015, were obtained from PubMed, Embase and the China National Knowledge Infrastructure databases. Data were extracted and pooled mean differences (MDs) with 95% confidence intervals (CIs) were calculated. Ultimately, eight studies were included, comprising 299 LP/OLP cases and 231 control subjects. Overall, the pooled MD for IL-6 was 16.24 (95% CI, 9.84-22.64; I²=99% for heterogeneity). In the subgroup analysis by ethnicity, a significant increase of the IL-6 expression level was identified among Asian individuals, but not in Caucasian individuals. Thus, IL-6 may be significant in the pathogenesis of LP. However, further studies are required to validate these associations.

Overexpression and varied clinical significance of Th9 versus Th17 cells in distinct subtypes of oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) presents with large numbers of T lymphocytes accumulating beneath the epithelium of the oral mucosa; however, its aetiology remains obscure. A potential role for an emerging novel T cell subset, Th9, in OLP has recently been suggested but remains to be clarified. The current aim was to investigate the expression and potential clinical significance of Th9 cells in distinct subtypes of OLP.

MATERIALS AND METHODS

Peripheral blood samples were collected from 41 OLP patients and 18 healthy controls (HCs). Flow cytometric analysis was used to detect the CD4+ T helper subset Th9 (IL-9⁺IL-17^-CD4⁺ Th cells) and Th17 (IL-9^-IL-17⁺CD4⁺ Th cells) expression levels.

RESULTS

Flow cytometry results showed significantly elevated levels of Th9 cells in reticular and erosive OLP compared to HCs. Th9 expression in erosive OLP was less than in reticular OLP, indicating that Th9 but not Th17 cells may play a predominant role in reticular disease. However, in erosive OLP patients, we found much higher levels of Th17 cells compared to reticular OLP patients and HCs, indicating that Th17 dominates in erosive OLP. Statistical analysis showed positive correlations of Th9 cells and Th17 cells in patients with reticular or erosive OLP but none in HCs.

CONCLUSIONS

Th9 and Th17 cells may take the predominant roles in reticular and erosive OLP respectively, and their numbers were positively correlated in reticular and erosive OLP patients. Elevated circulating Th9 cells may help maintain immune balance in OLP immunopathogenesis, which requires further investigation.

Association between polymorphisms in interleukins and oral lichen planus: A meta-analysis

BACKGROUND

More and more studies have suggested that single-nucleotide polymorphisms (SNPs) in interleukin (IL) genes are correlated with an increased risk of developing oral lichen planus (OLP). However, these results were inconsistent. Therefore, the aim of this meta-analysis is to retrieve and comprehensively analyze all related clinical studies to investigate the association of ILs gene polymorphisms with the OLP risk.

METHODS

PubMed, Embase, and the Cochrane Library were searched for eligible studies to evaluate the association between IL polymorphisms and the OLP. The odds ratios (ORs) and 95% confidence intervals (CIs) from each study were pooled to estimate the strength of the association. Statistical analyses were performed by using STATA software.

RESULTS

In all 6 studies, including 4 SNPs (IL6-174G/C, IL10-592C/A, IL10-819C/T, and IL10-1082G/A), 362 OLP patients and 622 non-OLP control subjects from five different countries were investigated. As for the IL6-174G/C, IL10-819C/T, and IL10-1082G/A, no evidence was found to support the association between SNP and OLP susceptibility in any genetic models. However, as for IL10-592C/A, a significant relationship between them was identified in all of comparison models (C vs A: OR = 0.724, 95% CI = 0.585-0.897, P = 0.003; CC vs AA: OR = 0.447, 95% CI = 0.276-0.722, P = 0.001; AC vs AA: OR = 0.585, 95% CI = 0.387-0.883, P = 0.011; CC+AC vs AA: OR = 0.544, 95% CI = 0.365-0.809, P = 0.003; CC vs AA+AC: OR = 0.715, 95% CI = 0.515-0.994, P = 0.046).

CONCLUSION

With the presently available evidence, this meta-analysis fails to show the statistical associations between IL6-174G/C, IL10-819C/T, and IL10-1082G/A and OLP susceptibility in any genetic models. However, the A allele and AA genotype in IL10-592C/A polymorphism may increase the risk of OLP. In the future, more well-designed studies with larger sample sizes are needed.

Role of distinct CD4(+) T helper subset in pathogenesis of oral lichen planus

Oral lichen planus (OLP) is one of the most common chronic inflammatory oral mucosal diseases with T-cell-mediated immune pathogenesis. In subepithelial and lamina propria of OLP local lesions, the presence of CD4(+) T helper (CD4(+) Th) cells appeared as the major lymphocytes. These CD4(+) T lymphocytes can differentiate into distinct Th cell types such as Th1, Th2, Treg, Th17, Th22, Th9, and Tfh within the context of certain cytokines environment. Growing evidence indicated that Th1/Th2 imbalance may greatly participate into the cytokine network of OLP immunopathology. In addition, Th1/Th2 imbalance can be regulated by the Treg subset and also greatly influenced by the emerging novel CD4(+) Th subset Th17. Furthermore, the presence of novel subsets Th22, Th9 and Tfh in OLP patients is yet to be clarified. All these Th subsets and their specific cytokines may play a critical role in determining the character, extent and duration of immune responses in OLP pathogenesis. Therefore, we review the roles of distinct CD4(+) Th subsets and their signature cytokines in determining disease severity and susceptibility of OLP and also reveal the novel therapeutic strategies based on T lymphocytes subsets in OLP treatment.

Role of serum interleukin-6 in deciding therapy for multidrug resistant oral lichen planus

Background

Oral lichen planus (OLP) is a T cell mediated immune response. T cells locally present in the involved tissues release cytokines like interleukin-6 (IL-6), which contributes to pathogenesis of OLP. Also IL-6 has been associated with multidrug resistance protein (MRP) expression by keratinocytes. Correspondingly, upregulation of MRP was found in OLP. We conducted this study to evaluate the effects of various drugs on serum IL-6 in OLP; and correlation of these effects with the nature of clinical response and resistance pattern seen in OLP lesions with various therapeutic modalities. Thus we evaluated the role of serum IL-6 in deciding therapy for multidrug resistant OLP.

Material and Methods

Serum IL-6 was evaluated in 42 erosive OLP (EOLP) patients and 10 normal mucosa and 10 oral squamous cell carcinoma cases using ELISA technique. OLP patients were randomly divided into 3 groups of 14 patients each and were subjected to Pimecrolimus local application, oral Mycophenolate Mofetil (MMF) and Methotrexate (MTX) alongwith Pimecrolimus local application. IL-6 levels were evaluated before and after treatment.

Results

Serum IL-6 levels were raised above 3pg/ml in 26.19% erosive OLP (EOLP) cases (mean- 3.72±8.14). EOLP (5%) cases with IL-6 levels above 5pg/ml were resistant in MTX group. However significant decrease in serum IL-6 corresponding with the clinical resolution was seen in MMF group.

Conclusions

Significantly raised IL-6 levels in EOLP reflect the chronic inflammatory nature of the disease. As serum IL-6 levels significantly decreased in MMF group, correspondingly no resistance to treatment was noted. However with MTX there was no significant decrease in IL-6 and resistance to treatment was noted in some, especially plaque type lesions. Thus IL-6 can be a possible biomarker in deciding the best possible therapy for treatment resistant OLP.

Key words:Lichen planus, biological markers, cytokines, enzyme-linked immunosorbent assay, immunosuppressive agents.

Pitanga (Eugenia uniflora L.) fruit juice and two major constituents thereof exhibit anti-inflammatory properties in human gingival and oral gum epithelial cells

Pitanga, Eugenia uniflora L., is a tropical fruit, which may be consumed as juice. While beneficial health effects of Eugenia uniflora L. leaf extracts have extensively been studied, limited data are available on an anti-inflammatory potential of pitanga juice. The aim of the presented study was to investigate anti-inflammatory properties of pitanga juice with regards to a prevention of inflammation-related periodontal diseases. For this purpose, six healthy volunteers swirled pitanga juice, containing 35% pitanga pulp, for 10 min. Thereafter, oral gum epithelial cells were harvested using a sterile brush and stimulated with lipopolysaccharides from Porphyromonas gingivalis (PG-LPS) for 6 h. Furthermore, human gingival fibroblasts (HGF-1) were used to elucidate the anti-inflammatory potential of pitanga juice constituents, cyanidin-3-glucoside and oxidoselina-1,3,7(11)-trien-8-one, in juice representative concentrations of 119 μg ml(-1) and 30 μg ml(-1), respectively. For the first time, an anti-inflammatory impact of pitanga juice on gingival epithelial cells was shown by means of an attenuation of IL-8 release by 55 ± 8.2% and 52 ± 11% in non-stimulated and PG-LPS-stimulated cells, respectively. In addition, both cyanidin-3-glucoside and oxidoselina-1,3,7(11)-trien-8-one reduced the LPS-stimulated CXCL8 mRNA expression by 50 ± 15% and 37 ± 18% and IL-8 release by 52 ± 9.9% and 45 ± 3.7% in HGF-1 cells, when concomitantly incubated with 10 μg ml(-1)PG-LPS for 6 h, revealing an anti-inflammatory potential of the volatile compound oxidoselina-1,3,7(11)-trien-8-one for the first time.

Malignant transformation of oral lichen planus by a chronic inflammatory process. Use of topical corticosteroids to prevent this progression?

BACKGROUND

Oral lichen planus is a potentially malignant disorder with a capacity, although low, for malignant transformation. Of all the factors related to the process of malignant transformation, it is believed that the chronic inflammatory process plays a key role in the development of oral cancer. This inflammatory process is capable of providing a microenvironment based on different inflammatory cells and molecules that affect cellular growth, proliferation and differentiation.

OBJECTIVES

The objectives of our study are: to review the available evidence about the possible relationship between the chronic inflammatory process present in oral lichen planus and its malignant transformation, to discuss the potential therapeutic implications derived from this relationship and to study the role that topical corticosteroids play in the control of oral lichen planus inflammation and its possible progression to malignant transformation.

CONCLUSION

The maintenance of a minimum dose of topical corticosteroids could prevent the inflammatory progression of oral lichen planus to oral cancer.

Inflammation-related cytokines in oral lichen planus: an overview

Cytokines are powerful mediators which play a central role in both innate and adapted immune responses. Aberrant productions of cytokines may lead to the onset of immune deficiency, allergy or autoimmunity, which are involved in the mechanisms of various immune-mediated inflammatory diseases. Oral lichen planus (OLP) is a chronic inflammation disease affecting the oral mucosa with unknown aetiology. Previous studies have described the abnormal expression patterns of various inflammation-related cytokines, such as IL-1, 2, 4, 5, 6, 8, 10, 12, 17, 18, TGF-β, IFN-γ and TNF-α, in lesions, saliva, serum and peripheral blood mononuclear cells from patients with OLP, which may reflect the immune dysregulation status and emerge as central players in the immunopathogenesis of OLP. Besides, the gene polymorphisms of several cytokines such as IFN-γ, TNF-α, IL-4, IL-10 have been found to be involved in the susceptibility of OLP. In this review, we gave a brief introduction of the characteristics and biological functions of these inflammation-related cytokines and summarized for the first time the current knowledge on the involvement of inflammation-related cytokines in OLP. Further research on the exact roles of these cytokines will aid the understanding of the pathogenesis and the identification of novel therapeutic approaches of OLP.

Oral lichen planus as a preneoplastic inflammatory model

Oral lichen planus (OLP) is a chronic oral inflammatory disease of unknown etiology. According to reports, 1-2% of OLP patients develop oral squamous cell carcinoma (OSCC) in the long run. While World Health Organization (WHO) classifies OLP as “a potentially malignant disorder,” it is still a matter of debate which mechanisms drive OLP to such a condition. The current hypothesis connecting OLP and OSCC is that chronic inflammation results in crucial DNA damage which over time results in cancer development. Initial studies investigating the OLP and OSCC link were mainly retrospective clinical studies. Over the past years, several amount of information has accumulated, mainly from molecular studies on the OLP malignant potential. This article is a critical review of whether OLP has a malignant potential and, therefore, represents a model of preneoplastic inflammation.

Oral symptom intensity, health-related quality of life, and correlative salivary cytokines in adult survivors of hematopoietic stem cell transplantation with oral chronic graft-versus-host disease

Oral chronic graft-versus-host disease (cGVHD) is a frequent, clinically significant sequela of allogeneic hematopoietic stem cell transplantation (HSCT). This study was designed to elucidate relationships among clinical characteristics of oral cGVHD and related oral pain and oral dryness, salivary proinflammatory cytokine interleukin (IL)-6 and IL-1alpha concentrations, and health-related quality of life (HRQL). An understanding of the characteristics and correlates of oral cGVHD manifestations and related symptoms, such as oral dryness, is fundamental to the development of therapeutic interventions. Oral cGVHD severity was assessed with the Oral Mucositis Rating Scale (OMRS). Oral pain and perceived intensity of oral dryness were self-reported via a visual analog scale and a numeric rating scale, respectively. HRQL was assessed with the Functional Assessment of Cancer Therapy-General (FACT-G). Salivary IL-1alpha and IL-6 concentrations were measured by enzyme-linked immunosorbent assay. All 42 adult subjects (59% males) had clinician-assessed oral cGVHD by the OMRS scale (mean score, 18.38 +/- 12.99; range, 2-46). Oral dryness (in 43% of subjects; mean OMRS score, 2.56 +/- 3.45; range, 0-10) was more prevalent than oral pain (8%; mean score, 0.13 +/- 0.47). Salivary IL-6 was associated with oral cGVHD severity (r = 0.49; P < .01), oral ulceration (r = 0.38; P = .04), and erythema (r = 0.63; P < .01). FACT-G total score and physical and emotional well-being subscale scores were meaningfully lower than U.S. population normative values. Participants with more severe oral cGVHD manifestations had significantly inferior social/family well being (r = -0.49; P < .01). Oral dryness was associated with higher salivary IL-1alpha (r = 0.41; P = .04) and, controlling for cGVHD severity, with lower HRQL (r = -0.41; P = .03). Subjects with moderate to severe oral dryness tended to report the poorest overall HRQL. This study provides preliminary evidence of the relationship between oral dryness and HRQL, the contribution of oral cGVHD to inferior HRQL, and the association between IL-6 and oral cGVHD severity, ulceration, and erythema. The high prevalence of oral dryness and its relationship to HRQL in a sample of subjects with oral cGVHD underscores the importance of improving our evaluation and management of this symptom in long-term survivors of allogeneic HSCT. The positive associations between IL-6 and oral cGVHD severity and erythema, as well as the positive trend with oral ulceration, warrant further exploration of this cytokine as a potential biomarker of active oral cGVHD.

Efficacy of Elaeagnus angustifolia Topical Gel in the Treatment of Symptomatic Oral Lichen Planus

Background and aims

The purpose of this study was to determine efficacy of 19% Elaeagnus angustifolia (EA) topical gel in the treatment of symptomatic oral lichen planus.

Materials and methods

Patients with symptomatic oral lichen planus referring to the Department of Oral Medicine, Fac-ulty of Dentistry at Shahid Beheshti University of Medical Sciences were asked to participate in the study. Twenty-eight pa-tients who were histopathologically diagnosed with lichen planus were divided into two groups (15 in the case and 13 in the control groups). The subjects were randomly assigned to either topical gel of EA or placebo in a double-blind manner. They were then instructed to apply the medication on dried lesions three times daily. Pain and size of the lesions were evaluated after 2 weeks. Data were analyzed by SPSS 12.0 software, using t-test, paired t-test, Fisher’s exact test and chi-square test.

Results

Twenty-eight patients (m/f: 7/21) with symptomatic oral lichen planus participated in the study. Fifteen patients (m/f: 4/11) received E A gel and 13 patients (m/f: 3/10) received placebo. There was a 75% decrease in pain (33.3% in the case and 7.7% in the control groups), and a decrease of 50% in size (33.3% in the case group) and 75% only in 7.6% of the case group.

Conclusion

The results suggest that 19% EA gel is efficient in the treatment of symptomatic oral lichen planus, with anti-inflammatory and analgesic effects, as well.

Investigation of functional gene polymorphisms interleukin-1β, interleukin-6, interleukin-10 and tumor necrosis factor in individuals with oral lichen planus

Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disease. There are some studies in the literature demonstrating association between cytokines genes polymorphisms and susceptibility to develop some immune-mediate conditions. The purpose of this study was to investigate cytokine gene polymorphisms in a sample of Brazilian patients with OLP. Fifty-three patients with OLP (mean age = 43.1 years; range 20-68 years) and 53 healthy volunteers (mean age = 42.9 years; range 21-67) were genotyped for IL-1beta +3954 (C/T), IL-6-174 (G/C), IL-10-1082 (G/A) and TNFA-308 (G/A) gene polymorphisms. Statistical analysis was based on the use of logistic regression (P-values below 0.05 were considered as significant). IL-6 and TNFA homozygous genotypes were significantly more often detected in OLP patients. These genotypes were associated with an increased risk of OLP development (OR 6.89 and 13.04, respectively). IL-1beta and IL-10 gene polymorphisms were not related to OLP development. Our findings clearly demonstrate an association between inheritance of IL-6 and TNFA gene polymorphisms and OLP occurrence, thus giving additional support for genetic basis of this disease.

Proinflammatory cytokine levels in saliva before and after treatment of (erosive) oral lichen planus with dexamethasone

OBJECTIVE

To explore the potential of detecting the level of proinflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin-1-alpha (IL-1-alpha), IL-6, and IL-8 in whole unstimulated saliva (WUS) in monitoring the therapeutic effects of topical dexamethasone on these salivary cytokines in subjects with erosive oral lichen planus (OLP).

STUDY DESIGN

Thirteen definitively diagnosed OLP subjects were enrolled in the study as were 13 age- and sex-matched controls. The OLP subjects were treated with 0.1% dexamethasone oral rinse for 6 weeks. Prior to treatment and at the end of clinical trial, the visual analog scale (VAS) for symptoms was recorded, WUS was collected and these proinflammatory cytokines were analyzed by ELISA.

RESULTS

Following the dexamethasone treatment, the levels of TNF-alpha, IL-1-alpha, IL-6, and IL-8 were decreased significantly, and IL-1-alpha and IL-8 were detected at a level without a statistically significant difference from controls. VAS value was decreased significantly and was found to significantly correlate with the decrease in IL-1-alpha and IL-8 levels.

CONCLUSIONS

These preliminary results indicate that salivary analysis of NF-kappaB-dependent cytokines may be applied to monitoring the therapeutic response of OLP.