Oral lichen planus and lichenoid reactions: etiopathogenesis, diagnosis, management and malignant transformation

A Randomized Placebo-controlled Double Blind Clinical Trial of Quercetin for Treatment of Oral Lichen Planus

Background and aims. Standard treatment of oral lichen planus (OLP) includes topical or systemic corticosteroids that have many adverse effects. A trend toward alternative natural or herbal drugs has attended recently. This study was conducted to evaluate the effect of quercetin in treatment of erosive-atrophic OLP.

Materials and methods. Thirty patients participated in this randomized clinical trial from April 2010 to June 2010 (Trial Registration Number: NCT01375101). Patients were randomly allocated in two groups. Both groups received the standard treatment (dexamethasone mouthwash and nystatin suspension). Experimental group received oral 250 mg quercetin hydrate capsules (bid) and the control group received placebo capsules. The pain and severity of the lesions were recorded at the initial visit and the follow-ups. All recorded data were analyzed with chi-square, Mann-Whitney, t-test, Wilcoxon and Friedman tests using SPSS 11.5.

Results. There were no significant differences between the two groups in severity of the lesions and pain in the follow-ups.According to the Friedman test, there was a significant reduction in pain (P = 0.01) and severity indices (P = 0.00) in the case group. These differences were not observed in the control group(P = 0.26,SI; and P = 0.86, PI). No adverse effect of quercetin was reported.

Conclusion. According to the results, no significant therapeutic effect can be considered for quercetin in treatment of OLP.

Oral lichenplanus: Etiology, pathogenesis, diagnosis, and management

Oral Lichen planus (OLP) is a common chronic mucocutaneous disorder with an immune mediated pathogenesis. Its appearance may vary from presence of keratotic to erythematous areas. Etiology of OLP is unknown, but it is thought to be the result of an autoimmune process with an unknown predisposing factor. Oral lichen planus is a complex and poorly understood clinical condition with periods of remissions and exacerbations. Management of the OLP is diversified with few lesions requiring treatment for years and few others are mild, requiring no treatment.

Prevalence of oral lichen planus among a sample of the Egyptian population

Objectives: To report on the prevalence of oral lichen planus among a sample of the Egyptian population. Study Design: 4470 Egyptian patients, aged 15-75 years, were seen at the outpatient clinic at the Faculty of Oral and Dental Medicine, Cairo University, Egypt. 31.25 % of these patients were males and 68.75% were females. Oral mucosal lesions consistent with oral lichen planus (OLP) were identified both clinically and confirmed histologically (in atypical cases) so that the prevalence of oral lichen planus in this study is 1.43%. Results: 64 patients were diagnosed with OLP (20 males and 44 females). The average age of the affected group was 48.07 years. Associated skin lesions were detected in 15/64 patients (23.44%) and tobacco habits was observed in 20/64 patients (31.25%). The average period of follow-up of the affected cases was 1-2 years, during which two cases developed squamous cell carcinoma of the oral lesion. Conclusions: Within the limitations of this study it revealed the prevalence of OLP among middle-aged women. Atrophic lesions were most frequent, followed by the erosive forms. Anti-HCV circulating antibodies were more common in patients with OLP and, notably, OLP was associated with Diabetes mellitus in 15.63% of patients.

Key words:Prevalence, oral lichen planus, Egypt.

Clinical characteristics of lichen and dysplasia vs lichen planus cases and dysplasia cases

OBJECTIVES

To compare the clinical characteristics of lichen planus with dysplasia (LD) cases with oral dysplasia (DYS), and LP/lichenoid reaction (LP/LR).

METHODS

Patients treated at the Department of Oral Medicine with a histological diagnosis were included. Patient information (age, gender, ethnicity, smoking habits, and medical status) and parameters of oral manifestation (lesions' distribution, site, and type) were compared.

RESULTS

Two hundred and thirty five patients were included. 54% were never smokers and 25% were current smokers. The LD group (n = 79) had more bilateral cases when compared to the DYS group (n = 30), 70% to 40.7%, respectively (P = 0.008), and a lower average age [56-62, respectively (P = 0.043)]. All other parameters were similar. When compared to LR patients, the LD group had a higher percentage of men [41.8-27.9%, respectively (P = 0.08)] while all other parameters were similar.

CONCLUSIONS

As clinical characteristics of LD are more similar to the LP and LR group than to dysplasia, these findings may indicate that LD should be considered as part of the lichen planus disorder spectrum rather than a separate entity, although further analysis of larger groups is warranted. These results support the need for clinical follow-up among patients diagnosed with lichenoid changes.

Evaluation of the Effects of Dental Implants on Oral Lesions

Objective

To determine whether dental implants impress oral lesions, and to evaluate the nature of their effect on the lesions.

Materials and methods

A comprehensive search was done via Google and PubMed for articles (including case reports and literature reviews) containing the keywords ‘oral squamous cell carcinoma’ (OSCC), ‘oral lichen planus’ (OLP), ‘lichenoid contact reaction’ (LCR), ‘osseointegrated implants’, and ‘dental implants’, in the last 10 years (2002-2012).

Results

The study included 24 articles involving patients with dental implants, and some oral lesions (e.g. oral lichen planus and oral squamous cell carcinoma) or with a history of lesions. In these publications, there is evidence suggesting the possibility of emergence, exacerbation, recurrence, or even malignant transformation of the oral lesions after implant placement in some cases.

Conclusion

Based on our review of the literature, implant treatment does not seem to be completely safe under any circumstances, but may have some complications in subjects with certain diseases (e.g. oral lesions, autoimmune diseases, malignancies, allergic reactions, etc.). Therefore prior to treatment, patients should be fully informed of the risks.

Clinical significance

Implant treatment is best done with caution in patients with cancer or mucocutaneous disorders.

How to cite this article

Agha-Hosseini F, Rohani B. Evaluation of the Effects of Dental Implants on Oral Lesions. J Contemp Dent Pract 2015;16(5):400-406.

Immune-mediated diseases: what can be found in the oral cavity?

Immune-mediated diseases frequently affect oral mucosa, which may often be the first site of clinical manifestation. In this review, we describe the most important oral lesions related to inflammatory disorders and present their management and novel therapies. The review is based on an open PubMed literature search from 1980 to 2012 with relevant keywords. Pemphigus vulgaris, oral lichen planus, cicatricial pemphigoid, erythema multiforme, Stevens-Johnson syndrome, systemic lupus erythematosus, Sjögren's syndrome, and linear IgA dermatosis are the immune-mediated diseases with oral manifestations discussed. Etiology is unknown in most of these diseases, but recently some of them have been found to share common genes. Modern treatment of these diseases is based on drugs that interfere along the pathogenic mechanisms instead of the still commonly used palliative measures. However, the immunomodulatory drugs may also cause oral side effects, complicating the clinical picture. Therefore, consulting dental or oral medicine specialists can be necessary in some cases with various immune-mediated diseases.

Salivary concentration of the antimicrobial peptide LL-37 in patients with oral lichen planus

Background

The antimicrobial peptide LL-37 is a significant molecule of innate immunity and recent studies indicate that it plays an important role in maintaining oral health. Yet limited knowledge exists on its role in oral diseases and oral lichen planus (OLP) in particular.

Objective

The study aimed to examine: 1) the salivary concentration of LL-37 in patients with OLP and healthy subjects, 2) the relation between the type (reticular or erosive) and size of OLP lesions and LL-37 concentration, and 3) the effect of the therapeutic modalities on LL-37 levels.

Design

The salivary peptide concentration in samples from 20 patients and 30 healthy subjects at the same age range was determined by ELISA.

Results

Despite the wide variation in peptide concentration found in both groups, the healthy subjects exhibited significantly lower levels than patients. Patients with the erosive form had significantly higher peptide concentrations than patients with the reticular form. Systemic treatment with corticosteroids resulted in a significant decrease of the salivary peptide concentration, while other treatment modalities, such as administration of vitamins A and E or local application of corticosteroids had no effect. Improved clinical appearance of the lesions was followed by a decrease in the salivary LL-37 level.

Conclusions

Salivary concentration of LL-37 correlates to the manifestation of mucosa lesions in OLP patients, the highest levels being observed in the most severe cases. This increase in peptide levels may protect against lesion infection and promote a quick wound healing.

A retrospective study of 171 patients with oral lichen planus in the East Bohemia - Czech Republic - single center experience

Objectives: Oral lichen planus is chronic inflammatory disease with a high prevalence in the population. This study describes the epidemiological and clinical characteristics of group of patients with oral lichen planus in the Czech Republic. Material and Methods: Data was taken from the medical records of 171 patients referred to the Oral Medicine Unit at the University Hospital in Hradec Králové with histologically confirmed clinical diagnosis of oral lichen planus in the period 2003 – 2013. The data were retrospectively reviewed. Results: Of the 171 patients, 116 (67.8%) were women and 55 (32.2%) were men. The mean age was 55.2 ± 12.4 years (range of 85.0 – 20.9). The reticular form was the most frequent 93.6% (160 pts.), desquamative gingivitis was 12.9% (22). The buccal mucosa was the site most affected 89.5% (153 pts.). The lesions were asymptomatic in 52 patients (30.4%). Extraoral lesions were observed in 20.5% (35 pts.) of the patients, skin involvement was in 16.4% (28 pts.). Smokers were 29 patients. Local treatment used 116 (67.8%), only 6 patients used systemic short tome corticoid therapy. No evidence between OLP and malignant transformation was observed. Conclusions: This retrospective study show very similar profile and clinical features of the patients with OLP as in other studies.

Key words:Oral lichen planus, clinical features, extraoral manifestation.

Lipid profile and metabolic syndrome status in patients with oral lichen planus, oral lichenoid reaction and healthy individuals attending a dental college in northern India - a descriptive study

BACKGROUND

Chronic inflammation causes disturbances in the lipid metabolism. When this dyslipidemia becomes prolonged it increases the risk of cardiovascular disease. Recent literature reveals similar dyslipidemia in patients with lichen planus. However, the results were not compared with lichenoid reactions.

OBJECTIVE

The aim of this study was to profile the lipid levels and metabolic syndrome status in patients with oral lichen planus (OLP), oral lichenoid reactions (OLR) and healthy individuals in order to evaluate their respective cardiovascular risk.

MATERIALS AND METHODS

This case-control descriptive study included 32 adults from the OPD visiting the Department of Oral Medicine, 18 with either oral lichen planus or oral lichenoid reactions and 14 age and sex matched healthy controls. Ethical clearance and informed consent were obtained. Their lipid levels, body mass index and metabolic syndrome status were evaluated. Statistical analyses were performed with the SPSS version 16.0 software.P≥0.05 was considered significant.

RESULTS

The key findings of this study were a) increased levels of S.cholesterol and LDL-C in OLP and OLR patients when compared to normal healthy individuals b) significantly higher S.triglyceride and VLDL in OLP when compared to OLR and c) lower HDL-C levels in OLP when compared to OLR. 2(18%) patients with OLP and 3(50%) with OLR were found to have high BMI suggestive of obesity whereas none of the normal individuals were obese.

CONCLUSION

There may be an association between chronic inflammation and dyslipidemia that increases the risk for cardiovascular disease. OLP and OLR patients have increased serum cholesterol and LDL-C when compared to normal adults. Further research on lipid levels in OLR are required to establish the findings of this study.

Clinicopathologic correlation of oral lichen planus and oral lichenoid lesions: a preliminary study

Oral lichen planus (OLP) and oral lichenoid lesions (OLL) are clinically and histologically similar lesions but their treatment planning and prognosis are different. The review of the literature indicates numerous criteria to distinguish these two lesions; however there is a lot of inconsistency. Thus, the aim of this study was to determine the correlation of histopathology and clinical OLP and OLL diagnosis and to clarify which histopathologic criteria could best distinguish these two diagnoses. A retrospective study showed that clinically diagnosed 92 OLPs and 14 OLLs have been confirmed histopathologically in 52.2% and 42.9% of cases, respectively. In addition, histopathology showed statistically significant more eosinophils (P<0.0005), plasma cells (P<0.0005), and granulocytes (P<0.05) in OLL than OLP. To establish histopathological diagnosis of OLP and OLL it should be mandatory to define the type of cells in mononuclear infiltrate, which can be associated more accurately with clinical feature and patient history. Therefore, currently accepted diagnostic criteria for OLP and OLL should be modified and validated on a larger number of patients taking into account particular distinguishing histopathological features.

Unilateral lichen planus: A rare case report

Oral lichen planus (OLP) is a mucocutaneous disease with well-established clinical and histopathological features. It has a prevalence of approximately 1%. The etiopathogenesis is poorly understood. The annual malignant transformation is less than 0.5%. There are no effective means to either predict or to prevent such event. Clinically, OLP present as bilateral symmetrical lesion and hence lichen planus isolated to a single oral site other than the gingiva is very uncommon. On the other hand lichenoid reaction (LR) are the lesions which are similar clinically and histopathologically with OLP, but they are induced with some drug reaction and usually they do not show bilateral pattern like lichen planus. We reported a very uncommon case of unilateral lichen planus which was clinically diagnosed as LR, but in the absence of any cause-effective relationship biopsy was taken for histopathological examination Histopathologically, LR cannot be differentiated with OLP, so the final diagnosis was made on the immunohistochemical ground.

HBO: a possible supplementary therapy for oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are chronic inflammatory diseases in which cells suffer hypoxia referring to deprivation of adequate oxygen supply. Hyperbaric oxygen treatment (HBO), which can increase oxygen tension and delivery to oxygen-deficient tissue, is a supplementary therapy to improve or cure disorders involving hypoxia. Although the applications of HBO in wound healings, acute ischemic stroke, radiation-induced soft tissue injury and cancers are extensively reported, there are only few studies on their effect in OPMDs. Not only does HBO furnish oxygen-it also possesses potent anti-inflammatory properties. At the cellular level, HBO can decrease lymphocyte proliferation and promote apoptosis of fibroblasts. At the molecular level, it can decrease expression of HIF, ICAM-1, TNF-α, TGF-β, and IFN-γ, as well as increase vascular VEGF expression and angiogenesis. Thus, we hypothesize that HBO may contribute to treat OPMDs, including oral lichen planus, oral leukoplakia, and oral submucous fibrosis both at the cellular level and the molecular level, and that it would be a safe and inexpensive therapeutic strategy.

Simple and Effective Cryosurgical Treatment of Various Oral Lesions

The objective of this study was to evaluate the efficacy of cryosurgery on 134 different benign oral lesions in 90 patients. All lesions were treated every 2 weeks until complete regression of the lesion had been achieved. Patients were examined at 2, 7, and 10 days, 2 and 4 weeks, and 3 and 6 months after the cryosurgery. The relationship between the number of cryosurgery applications to achieve complete regression and the type of lesions was assessed for statistical significance by one-way analysis of variance and with the Scheffé test. The mean application number of the cryosurgery was 1.82±0.49 for fibroma, 2.35±1.44 for vascular lesions, 1.50±0.70 for mucocele, 2.65±1.18 for lichen planus lesions. The difference between the type of the lesion and number of application was statistically significant for all groups (p< 0.05). Our data prove that a significantly fewer number of cryosurgery treatments are required to achieve complete regression for fibroma and mucocele lesions compared to lichen planus lesions. During the follow-up period, only 7 lichen planus lesions of 76 lesions recurred.

Estimation of serum and salivary immunoglobulin G and immunoglobulin A in oral pre-cancer: A study in oral submucous fibrosis and oral lichen planus

Aim:

Oral submucous fibrosis (OSMF) and oral lichen planus (OLP) are two frequently reported, potentially malignant disorders with multifactorial etiologies and ambiguous pathogenesis. An immunological pathogenesis has been hypothesized as a causative factor for both. The present study aims to evaluate the role of serum and salivary immunoglobulin G (IgG) and immunoglobulin A (IgA) in both these conditions, by their quantitative estimation.

Materials and Methods:

Saliva and serum samples were collected from 30 patients, clinically diagnosed and histopathologically confirmed with OSMF, 30 with OLP and 30 age and sex matched controls. The levels of IgG and IgA were estimated by nephelometry.

Results:

The mean values of serum IgG were marginally higher in both OSMF and OLP groups compared to the controls but this difference was not significant and the mean values of serum immunoglobulin A were marginally decreased in both the study groups compared to the controls but this difference was also not significant. Inconclusively low levels of salivary IgG and IgA were obtained in the three groups.

Conclusion:

The present study suggests an insignificant association of these immunoglobulins in the pathogenesis of both these diseases.

Treatment of esophageal stricture due to lichen planus with intralesional corticosteroid injection

Herein we presented a male patient with esophageal stricture due to lichen planus successfully treated with repeated injections of intralesional triamcinolone and review the current literature on esophageal lichen planus with special emphasis on its treatment.

Management for premalignant lesions of the oral cavity

Premalignant lesions of the oral cavity present as visibly abnormal areas of mucosa and may be a source of significant anxiety for the patient and the clinician. Suspicious lesions should be biopsied to evaluate for dysplasia. The risk of malignant transformation may relate to patient characteristics, environmental risk factors and genetic alterations. Management of such lesions hinges on risk modification, surveillance, symptom management and directed biopsies. Excision or ablation of dysplastic lesions is indicated. We review the current evidence relating to management of premalignant lesions of the oral mucosa and make recommendations for practice patterns.

Oral mucosal health in liver transplant recipients and controls

Immunosuppressive drugs and other medications may predispose patients to oral diseases. Data on oral mucosal health in recipients of liver transplantation (LT) are limited. We, therefore, recruited 84 LT recipients (64 with chronic liver disease and 20 with acute liver failure) for clinical oral examinations in a cross-sectional, case-control study. Their oral health had been clinically examined before transplantation. The prevalence of oral mucosal lesions (OMLs) was assessed in groups with different etiologies of liver disease and in groups with different immunosuppressive medications, and these groups were compared to controls selected from a nationwide survey in Finland (n = 252). Risk factors for OMLs were evaluated with logistic regression. OMLs were more frequent in LT recipients versus controls (43% versus 15%, P < 0.001), and the use of steroids raised the prevalence to 53%. Drug-induced gingival overgrowth was the single most common type of lesion, and its prevalence was significantly higher for patients using cyclosporine A (CSA; 29%) versus patients using tacrolimus (TAC; 5%, P = 0.007); the prevalence was even higher with the simultaneous use of calcium channel blockers and CSA (47%) or TAC (8%, P = 0.002). Lesions with malignant potential such as drug-induced lichenoid reactions, oral lichen planus-like lesions, leukoplakias, and ulcers occurred in 13% of the patients with chronic liver disease and in 6% of the controls. Every third patient with chronic liver disease had reduced salivary flow, and more than half of all patients were positive for Candida; this risk was higher with steroids. In conclusion, the high frequency of OMLs among LT recipients can be explained not only by immunosuppressive drugs but also by other medications. Because dry mouth affects oral health and OMLs may have the potential for malignant transformation, annual oral examinations are indicated.

Squamous Cell Carcinomas of the Anterior Oral Cavity Are Commonly Associated With Simplex (or Differentiated) Oral Intraepithelial Neoplasia

Introduction: We investigated the occurrence of differentiated oral intraepithelial neoplasia (DOIN) that met the criteria for differentiated intravulvar neoplasia, associated with invasive squamous cell carcinoma (SCC) of the anterior oral cavity, and its clinicopathologic significance. Materials and Methods: Sixty-nine consecutive cases of SCC of the anterior oral cavity were categorized into 2 groups: group A comprised SCC associated with DOIN; Group B consisted of cases associated with classical SCC in situ. Results: Fifty-five cases (80%) were classified as group A, or DOIN lesions, with only 14 (20%) as group B. All cases were associated with invasive SCC, except 2 cases in group B. Squamous epithelium continuous or adjacent to invasive SCC displayed consistent changes in the parabasal and basal layers with (1) cytologic atypia with proliferation of parabasal cells in downward expansion causing reactive proliferation of the basal cell layer in early stage and invading the basal layer in late stage, (2) disordered nuclear/cytoplasmic arrangement, and (3) a “cobblestone” appearance characterized by prominent intercellular spaces and cytoplasmic density involving the entire cell (dyskeratosis) of the parabasal layer. p53 and Ki67 immunostaining revealed linear reactivity mainly in the parabasal layer. Conclusions: DOIN lesions are frequently associated with invasive SCC of anterior oral cavity. Due to the subtle histopathologic changes, DOIN lesions pose potential diagnostic difficulty with differentiation from mild dysplasia or reactive atypia.

Dermatological Conditions Mimicking Trauma

A number of dermatological findings may mimic inflicted injury in forensic investigations and lead to false conclusions about the circumstances, manner, and mechanism of death. At times, organic dermatological phenomena involving the skin, hair, and nails are initially misidentified as trauma, sexual abuse, or burns. History, autopsy, and histopathology aid in correctly diagnosing these dermatological findings. Some of the resulting diagnoses include pruritic, ulcerating, and infectious skin diseases, skin disease localized to the anogenital area, malignancy, medication-induced dermatoses, alopecia, and age-related skin changes. We report several cases where police and/or the coroner initially attributed a finding to trauma, but it was subsequently determined that the finding represented a dermatological disease by the forensic pathologist upon autopsy. In addition, for completeness, we include examples of other dermatological conditions that may mimic trauma. Forensic investigators should maintain a broad differential for abnormal skin, hair, and nail findings when there is an incomplete or incongruent history surrounding a victim's death.

Interrelationship of dendritic cells, type 1 interferon system, regulatory T cells and toll-like receptors and their role in lichen planus and lupus erythematosus -- a literature review

There is evidence that the activation of some receptors of the toll-like family (TLRs) of the innate immune system, and also changes in expression levels of forkhead box p3 (Foxp3) protein, which is found in regulatory T cells (Tregs), could be involved in the development of autoimmunity. We present here a literature review focusing on the interrelationship of dendritic cells, TLRs, Tregs and type 1 interferon in autoimmune diseases, with special interest in lichen planus and lupus erythematosus. Understanding the specific role of each of these factors would help elucidate the obscure aetiology of such diseases and open new perspectives for their management and treatment.

Analysis of the changes in the basal cell region of oral lichen planus: An ultrastructural study

Context:

Oral lichen planus (OLP) affects 0.5-1% of the total world's population. The histological features of oral lichen planus were first described by Dubreuill in 1906. Despite the advent of various techniques, the etiology of lichen planus remains obscure, although many theories for the etiology have been proposed.

Aims:

By studying OLP electron microscopically, we shall be emphasizing on the cells and its interactions in specific/altered surroundings which would help us in hypothesizing the effects of its specific cell-to-cell interactions.

Materials and Methods:

A total of 20 cases of oral lichen planus were selected and categorized into erosive and nonerosive forms based upon clinical pattern and confirmed as lichen planus by histopathological analysis. Tissue specimens thus obtained were cut into two halves and fixed in appropriate fixatives, i.e., neutral buffered formalin for paraffin-embedded hematoxylin and eosin stained sections and 2.5% glutaraldehyde and 2% paraformaldehyde for electron microscopic purpose respectively.

Results:

Ultrastructural comparison among the two forms showed significant differences between them. The basal layer showed cytoplasmic processes, intercellular spaces, desmosomes, nuclei, and signs of degeneration. The erosive form showed elongated, narrow or irregular cytoplasmic projections whereas the nonerosive showed short and broad based projections.

Conclusions:

The present study confirms the ultrastructural findings of basal cells in OLP with previous authors findings. Besides this, the categorization of the ultrastructural differences between erosive and nonerosive has raised the question of difference in the probable cellular and molecular mechanism between erosive and nonerosive forms.

Increased P-wave dispersion in patients with newly diagnosed lichen planus

OBJECTIVE

Lichen planus is a chronic inflammatory autoimmune mucocutaneous disease. Recent research has emphasized the strong association between inflammation and both P-wave dispersion and dyslipidemia. The difference between the maximum and minimum P-wave durations on an electrocardiogram is defined as P-wave dispersion. The prolongation of P-wave dispersion has been demonstrated to be an independent risk factor for developing atrial fibrillation. The aim of this study was to investigate P-wave dispersion in patients with lichen planus.

METHODS

Fifty-eight patients with lichen planus and 37 age- and gender-matched healthy controls were included in this study. We obtained electrocardiographic recordings from all participants and used them to calculate the P-wave variables. We also assessed the levels of highly sensitive C-reactive protein, which is an inflammatory marker, and the lipid levels for each group. The results were reported as the means ± standard deviations and percentages.

RESULTS

The P-wave dispersion was significantly higher in lichen planus patients than in the control group. Additionally, highly sensitive C-reactive protein, LDL cholesterol, and triglyceride levels were significantly higher in lichen planus patients compared to the controls. There was a significant positive correlation between highly sensitive C-reactive protein and P-wave dispersion (r=0.549, p<0.001) in lichen planus patients.

CONCLUSIONS

P-wave dispersion increased on the surface electrocardiographic measurements of lichen planus patients. This result may be important in the early detection of subclinical cardiac involvement. Increased P-wave dispersion, in terms of the tendency for atrial fibrillation, should be considered in these patients.

Disease-associated miRNA-mRNA networks in oral lichen planus

Background

A large number of pathophysiological mechanisms are regulated by microRNAs (miRNAs), which represent a new class of posttranscriptional regulators of gene expression. To date, little is known about their role in oral lichen planus (OLP), a chronic inflammatory mucocutaneous disease of unknown etiology which is being discussed as a potentially premalignant condition of oropharyngeal cancer. The aim of the present investigation was to assess the pathophysiological impact of miRNAs and to determine regulatory miRNA networks which are directly linked to potentially disease-associated target transcripts in OLP.

Methods

Native tissue samples were collected from the oral mucosa of seven patients with OLP. The control group was composed of native tissue from elective oral surgery. The mRNA profiling was performed using the Affymetrix Human Gene 1.0 ST Array while miRNA profiling was performed using the microRNA Galaxy Array. Subsequent validation of initial results was carried out using TaqMan real time PCR.

Results

We identified 24 differentially regulated miRNA and 2,694 regulated transcripts. Linking the miRNAs to their potential targets we found 11 potential miRNA-mRNA pairs, of which several are functionally related to premalignant as well as to inflammatory events.

Conclusions

Our data shows miRNA associated with transcripts which are regulated when comparing OLP patients with healthy control individuals. This suggests that miRNAs may potentially regulate disease-relevant transcripts, proposing the concept of therapeutic interventions based on miRNAs.

Oral lichen planus: focus on etiopathogenesis

Lichen planus is a chronic mucocutaneous inflammatory disease, which frequently affects the oral mucosa of white females over 40 years old. Its aetiology remains uncertain and the pathogenesis is still the object of much speculation. The present paper presents the most well known antigens, and describes the action of different cells and proteins associated with the development of that disease, as well as the possible agents involved with its malignant transformation. Different external agents, especially virus, and internal agents, like stress, and the heat shock protein antigen expression, associated or not, can alter the basal keratinocytes of the oral mucosa making them susceptible to apoptosis by CD8(+) cytotoxic T cell as well as activate matrix metalloproteinase and mast cell degranulation, which produce a great range of inflammatory mediators and cytokines determining the clinical onset of the disease. Regarding carcinogenesis, since it is a complex process and presents multifactorial origin, it is believed that there may be a synergism between intrinsic, such as inflammation mediators, and extrinsic agents (tobacco, alcohol, viral infections) for the OLP malignant transformation to occur. However, further studies are needed to better understand the origin, pathogenesis and process of malignant transformation of OLP.

Triology of nitric oxide, mast cell and stress in pathogenesis of oral lichen planus

INTRODUCTION

Oral Lichen planus (OLP) is chronic, autoimmune, mucocutaneous disease. Numerous etiological factors have been proposed, but an authoritative and exact source of the disease has not been brought forward. Reactive nitrogen species (RNS), mast cell (MC) and stress are considered to play a key role in inflammation-mediated carcinogenesis generating nitric oxide (NO).

AIM

To evaluate the salivary NO levels, mast cells and stress levels and to correlate them in pathogenesis of OLP.

MATERIALS AND METHODS

The study was conducted using saliva samples of patients. The study consisted of two groups: Group-I constituted the subjects with OLP group (n=25) and group II comprised the control group (n=25). The saliva of the patients was evaluated using Griess Reagent and Spectrophotometer, MC count done by using special stains, and stress levels measured using DASS Scale.

RESULTS

The difference between the means was found to be highly significant (P < 0.05). The intergroup comparison of optical density (OD) values, a mast cell count and stress level was found to be highly significant.

CONCLUSION

Salivary NO, increase in mast cell count and stress has a definitive role in OLP pathogenesis.

Bioinformatics and systems biology analysis of genes network involved in OLP (Oral Lichen Planus) pathogenesis

BACKGROUND

Genes involved in different biological processes form complex interaction networks. However, only few of them have a high number of interactions with the other genes in the network and therefore they may play a major role. In previous bioinformatics and experimental studies, these genes were identified and termed as "leader genes". In the current ab initio theoretical study, genes involved in human OLP (Oral Lichen Planus) pathogenesis are identified and ranked according to their number of interactions, in order to obtain a broader view of its molecular mechanisms and to plan targeted experimentations.

METHODS

Genes involved or potentially involved in OLP were identified by systematically querying several databases until the identification of a final set of genes. Interactions among these genes were mapped and given a significance score using STRING database. For each gene, significance scores were summed to obtain a weighted number of links (WNL) and subsequently genes were clustered according to this parameter. The genes in the highest cluster were termed as leader genes; the other ones were ranked as class B genes, class C genes, and so on. This study was complemented by a topological analysis of the network, carried out using Cytoscape, BinGO and FANMOD software.

RESULTS

The interactions in the obtained network showed power law behaviour, in agreement with the scale-free topology theory of the biological graphs. 132 genes were identified and five of them (namely, JUN, EGFR, FOS, IL2, ITGB4) were classified as leaders. Interestingly, all of them but EGFR were up-regulated and were widely distributed in the network (in term of topological parameters such as stress, eccentricity and radiality) and showed higher topological coefficients than the other genes.

CONCLUSIONS

Even with the limitations of any ab initio analysis, this study can suggest targeted experimentation, focused on the leader genes and therefore simpler to be analysed than mass scale molecular genomics. Moreover, it may suggest new potential risk factors and therapeutic targets.