Análise da imunoexpressão de BAX e MMP-9 no líquen plano oral / Analysis of BAX and MMP-9 immunoexpression in oral lichen planus

Introdução: O líquen plano oral é uma doença crônica imunologicamente mediada relativamente comum, que acomete a mucosa oral. Clinicamente, o LPO é classificado em seis padrões bem identificados: placa, reticular, bolhoso, atrófico, papular e erosivo.Sendo os mais comuns oos tipos reticulares e erosivos. A ativação dos linfócitos TCD4+ no LPO, pode induzir os ceratinócitos ao processo de apoptose através da respostaimunológica citotóxica. A proteína Bax desempenha uma função relevante para o processo apoptótico. Deste modo, a presente pesquisa consistiu em um estudo transversal retrospectivo, descritivo, quantitativo e comparativo. Objetivo: Avaliar a expressão imuno-histoquímica das proteínas MMP9 e Bax no LPO. Método: Foram utilizados 43 casos de LPO para análise da imunoexpressão de Bax e MMP-9. Os resultados foram analisados através dos testes estatísticos apropriados e serão considerados significativos, valores onde p<0,05. Resultado: A imunoexpressão de MMP9 foi significativamente maior nos ceratinócitos e quando analisados os subtipos de líquen plano oral, não foram observados diferenças estatísticas entre os tipos reticulares e erosivos para as proteínas analisadas. Conclusões: Com essas observações, infere-se que a alteração na expressão das proteínas estudadas sugere um distúrbio nos mecanismos apoptóticos, os quais estão associados às lesões de LPO, e podemos concluir também que as imunoexpressões dessas proteínas não apresentaram diferença, quando relacionada ao tipo clínico reticular ou erosivo. Com esse resultado pode-se contribuir para um maior entendimento sobre os possíveis mecanismos celulares envolvidos na etiopatogenia dessa lesão (AU).

Background: Oral lichen planus is a relatively common immune-mediated chronic disease that affects the oral mucosa. Clinically, OLP is classified into six well-identified patterns: plaque, reticular, bullous, atrophic, papular, and erosive. The most common being the reticular and erosive types. The activation of TCD4+ lymphocytes in the OLP can induce keratinocytes to the process of apoptosis through the cytotoxic immune response. Thus, the present research consisted of a retrospective, descriptive, quantitative and comparative crosssectional study. Objective: to evaluate the immunohistochemical expression of MMP-9 and Bax proteins in OLP. Methods: We used 20 cases of Inflammatory Fibrous Hyperplasia as control. The results were analyzed through the appropriate statistical tests and will be considered significant, values where p<0.05. Results: The immunoexpression of MMP-9 was significantly higher in keratinocytes and when the subtypes of oral lichen planus were analyzed, no statistical differences were observed between the reticular and erosive types for the proteins analyzed. Conclusions: With these observations, it is inferred that the alteration in the expression of the studied proteins suggests a disturbance in the proliferative and apoptotic mechanisms, which are associated with a pathological behavior of the oral mucosa, and consequently with a repercussion on the lesions of OLP, and we can also conclude that the immunoexpression of these proteins had no difference, when related to the reticular or erosive clinical type. This research aims to contribute to a greater understanding of the possible cellular mechanisms involved in the etiopathogenesis of this lesion, thus enabling the understanding of the clinical aspects of the pathology (AU).

Análise clínico-patológica e qualitativa da expressão de mediadores inflamatórios teciduais no líquen plano oral / Clinicopathological and qualitative analysis of the expression of tissue inflammatory mediators in oral lichen planus

O líquen plano oral (LPO) é uma condição imuno-inflamatória mucocutânea crônica que ainda possui etiologia e patogênese desconhecidas. Estudos mostrando a participação de citocinas no LPO, em especial, interleucinas (IL)-6, IL-17 e IL-18, são escassos, assim como a correlação das características clínicas e histológicas das lesões de LPO com a presença destes mediadores inflamatórios. Todas as lesões de LPO e de lesões liquenoides orais (LLO) foram revisadas a partir do arquivo do laboratório de Patologia Bucal da Faculdade de Odontologia da Universidade do Estado do Rio de Janeiro e as características clínico-patológicas dos casos foram analisadas. Foram selecionados 40 casos de LPO para realização adicional de reações imuno-histoquímicas para IL-6, IL-17 e IL-18. A amostra total foi composta por 221 casos e mostrou que o LPO apresentou predileção por mulheres adultas, mais frequentemente acometidas pelo padrão reticular e com lesões localizadas predominantemente na mucosa jugal. Os 40 casos selecionados para a avaliação imuno-histoquímica incluíram pacientes com média de idade de 53 anos, sem predileção por gênero, e com lesões localizadas preferencialmente na mucosa jugal (85%), na gengiva/mucosa alveolar (47%) e na língua (42%). Quanto ao padrão clínico, 14 pacientes (35%) mostravam lesões exclusivamente reticulares e 26 (65%) mostravam lesões reticulares associadas a lesões atrófico-erosivas. Sintomas foram relatados por 53% dos pacientes e incluíram principalmente ardência e desconforto local. A análise histológica mostrou que o epitélio das lesões mostrava espessura normal, atrófica ou hiperplásica em, respectivamente, 17 (43%), 9 (22%) e 14 (35%) casos. A presença de hiperqueratose foi observada em 21 casos (53%) e exocitose de linfócitos T CD4+ e T CD8+ estava presente em, respectivamente, 17 (42%) e 30 (75%) casos. A análise imuno-histoquímica revelou que a IL-6 foi, de forma geral, a mais expressa, tanto no epitélio, quanto no conjuntivo. A expressão de IL-17 se mostrou intensa no tecido conjuntivo, em 40% dos casos. A IL-18 mostrou intensidade mais frequente leve/moderada tanto no epitélio (40%), quanto no tecido conjuntivo (45%). A presença de exocitose mostrou relação com a maior expressão das ILs e a expressão de IL-17 foi maior no epitélio mostrando hiperqueratose. Os resultados do presente estudo mostraram que as características clínicas das lesões de LPO e de LLO são distintas e podem ser utilizadas para diferenciação entre as duas entidades. Os achados histológicos e imunohistoquímicos sugerem que as ILs estudadas mostram-se mais presentes quando há exocitose linfócitos T CD4+ e T CD8+ e que sua expressão pode ter relação com as alterações epiteliais encontradas no LPO, participando da patogênese e da modulação da expressão da doença.

Oral lichen planus (OLP) is a chronic immunoinflammatory mucocutaneous condition of unknown etiology and pathogenesis. Studies focusing on the presence of cytokines in OLP, especially interleukin (IL)-6, IL-17 and IL-18, are scarce, as well as the correlation of clinical and histological characteristics with the presence of inflammatory mediators. All lesions diagnosed as OLP and oral lichenoid lesions (OLL) were reviewed from the files of the Oral Pathology laboratory, Dental School, Rio de Janeiro State University, and their clinicopathological characteristics were analyzed. Forty cases diagnosed as OLP were selected for additional immunohistochemical reactions directed against IL-6, IL-17 e IL-18. The total sample was composed by 221 cases and showed that OLP presented a predilection for adult females, mostly affected by lesions with the reticular pattern and located in the buccal mucosa. The 40 cases selected for the immunohistochemical reactions included patients with a mean age of 53 years, with no gender predilection, and with lesions located mostly in the buccal mucosa (85%), gingiva/alveolar mucosa (47%) and tongue (42%). The clinical pattern showed reticular lesions in 14 patients (35%) and reticular and atrophic/erosive lesions in 26 patients (65%). Symptoms were reported by 53% of the patients and included mostly burning sensation and local discomfort. Histological analysis showed that the epithelial thickness was normal, atrophic, or hyperplastic in, respectively, 17 (43%), 9 (22%) and 14 (35%) cases. The presence of hyperkeratosis was observed in 21 cases (53%), and exocytosis of T CD4+ and T CD8+ lymphocytes was present in, respectively, 17 (42%) and 30 (75%) cases. Immunohistochemical analysis showed that, in general, IL-6 was the most expressed IL both in epithelium and connective tissue. IL-17 expression was considered intense in the connective tissue from 40% of the cases. IL-18 expression was considered mostly mild/moderate both in epithelium (40% of the cases) and connective tissue (45% of the cases). The presence of exocytosis was associated with a higher expression of the ILs and expression of IL-17 was higher in epithelium showing hyperkeratosis. The results from the present study showed that the clinical characteristics of OLP and OLL are distinct and can be useful in differentiating these two diagnostic entities. The histological and immunohistochemical features suggest that the studied ILs are more expressed when there is exocytosis of both T CD4+ and T CD8+ lymphocytes. Expression of the ILs can be associated with the epithelial alterations encountered in OLP, participating in the pathogenesis and modulating the expression of the disease.

Cytokines, cortisol, and nitric oxide as salivary biomarkers in oral lichen planus: a systematic review

Abstract The etiopathogenesis of oral lichen planus (OLP) is still not fully elucidated, and it is believed that its development could involve a neuro-immune-endocrine profile. This systematic review investigated the relationship between cytokines, cortisol, and nitric oxide (NO) in the saliva of OLP patients. An electronic search was conducted in Pubmed/Medline, Scopus, LIVIVO, and Web of Science databases with no restriction of language to identify studies published up to December 2017. Data extraction was performed using the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. A total of 140 articles were retrieved, and 32 articles fulfilled the inclusion criteria (cytokines = 17; cortisol = 9; NO = 6). The most studied cytokines in the saliva of OLP patients were interleukins IL-4, IL-6, IL-8, IFN-ү, and TNF-α, which were higher in OLP patients than in healthy controls (HC). Salivary cortisol was found to be higher in OLP than in HC in most (55.5%) of the selected studies, and all studies related to NO found higher levels of this marker in OLP than in HC. Despite controversial results, our review suggests that OLP patients have an increased inflammatory response, as indicated by the proinflammatory profile of salivary cytokines. In addition, we conclude that salivary cytokine and NO measurements may have significant diagnostic and prognostic potential for monitoring disease activity and therapeutic responses in OLP.

P-glycoprotein expression in oral lichen planus

Abstract: Oral lichen planus (OLP) is a stress induced inflammatory condition with malignant potency. The mdr1 (multidrug resistance) is a stress gene overexpressed in cancerous conditions and its translated form, the p-glycoprotein efflux transporter is usually overexpressed with chemotherapy, leading to chemoresistance. OLP, a lesion with carcinogenic potency, is broadly classified into the asymptomatic reticular form and the aggressive erosive form. The objective of the study was to verify the expression level of p-glycoprotein in antifungal-treated and untreated reticular OLP, in untreated erosive OLP and erosive OLP patients treated with corticosteroid. Semi-quantitative reverse transcriptase polymerase chain reaction (SQ-RTPCR) and ELISA were performed on biopsy tissue samples to evaluate the mdr1 mRNA and protein expression of p-glycoprotein, respectively. The present study shows for the first time that mdr1 mRNA as well as its translated form p-glycoprotein are overexpressed in OLP subjects compared to healthy individuals. This overexpression is significantly higher in erosive than in reticular OLP patients, further confirming that the erosive form has higher risk for multidrug resistance. A higher expression is also observed in corticosteroid-treated erosive cases than similar untreated ones. The gradation of expression is in conformity with severity of the disease.

Differential expression of stem cell-like proteins in normal, hyperplastic and dysplastic oral epithelium

Objective The identification of stem cells (SC) remains challenging. In the human oral mucosal epithelium, these cells are believed to be in the basal layer (stem cell niche), but their exact location is unclear. The aim of this study was to examine the dysplastic oral epithelium for these SC-like proteins in order to assess their diagnostic value as biomarkers complementing the histological grading of dysplasia. Material and Methods Thirty oral epithelial dysplasia (OED), 25 oral lichen planus (OLP), 10 oral hyperkeratosis and 5 normal oral epithelium (OE) were immunohistochemically examined for four SC markers [integrin β1, neuron-glial-2 (NG2), notch 1 (N1) and keratin 15 (K15)]. Results Three of four SC markers were heterogeneously detected in all samples. K15 overexpression in the lower two-thirds of severe OED suggests an expanded SC niche. Integrin β1 distribution pattern was not measurably different between OEDs and control. NG2 was almost negative to absent in all samples examined. N1 expression was weak and highly variable in normal and dysplastic epithelium, making it an unreliable epithelial stem cell marker. Conclusions Present findings suggest that these markers were unable to identify individual epithelial stem cells. Instead, subpopulations of cells, most probably stem cells and transit amplifying cells with stem cell-like properties were identified in the dysplastic oral epithelium. The characteristic expressions of K15 might be of diagnostic value for oral dysplasia and should be investigated further. .

Estimation and comparison of levels of salivary nitric oxide in patients with oral lichen planus and controls

Normal salivary function is considered to be critical for the maintenance of healthy oral mucosa. Oral fluids provide an easily available, non-invasive medium for the diagnosis of wide range of diseases and clinical situations. The objective of this study was to estimate and compare salivary nitric oxide levels in patients with oral lichen planus and healthy individuals. To estimate the levels of salivary nitric oxide in patients with oral lichen planus and compare them with those of healthy subjects [controls]. Saliva was collected by spitting method. Unstimulated whole saliva thus collected was refrigerated at 4°C, and processed within 24h for the estimation of nitric oxide levels which was done using Griess reaction. The results were analyzed using Student's "t" test. There was statistically significant difference in the levels of salivary nitric oxide between the study and control groups. The present study clearly indicates a significant increase in salivary nitric oxide levels in oral lichen planus patients as compared to controls

Evaluation of salivary cortisol and psychological factors in patients with oral lichen planus.

Background and Objectives: Lichen planus is a relatively common chronic inflammatory disease of oral mucosa and skin. Cortisol, also called as "stress hormone", has been used as an indicator in various stress evaluation studies. Salivary cortisol measurement is an indicator of free cortisol or biologically active cortisol in human serum and provides noninvasive and easy technique. Recent studies have been conflicting, and hence, in the present study, evaluation of salivary cortisol levels and psychosocial factors in oral lichen planus (OLP) patients was done. Materials and Methods: A total of 30 patients with clinically and histopathologically proven cases of OLP, along with the age and sex-matched healthy controls were included in the study. Samples of stimulated saliva were collected, centrifuged and analyzed for the level of cortisol with cortisol enzyme linked immunosorbent assay. Psychosocial factors of study and control groups were measured by depression anxiety and stress scale. Student's t-test was used to compare the psychological factors and salivary cortisol levels between patients with the OLP and the control group. Results: Irrespective of sex, significantly higher depression (83.4 ± 15.4%), anxiety (80.5 ± 11.3%), and stress (94.2 ± 6.2%) scores were observed in OLP patients compared to controls. Increased cortisol levels were observed among 17 (56.6%) OLP patients in the study group. A positive correlation was found between psychological factors and salivary cortisol levels in the OLP patients. The values of Pearson's correlation coefficient "r", between depression, anxiety, and stress with salivary cortisol was: +0.42,S; +0.27,NS; and +0.65,HS, respectively among the study group.

Evaluation of salivary nitric oxide levels in oral mucosal diseases: A controlled clinical trial.

Lichen planus is a common dermatologic disease to manifest in the oral cavity. Recurrent aphthous ulcers are the most common ulcers of the oral cavity causing discomfort to the patients. These two diseases have different clinical manifestations which require appropriate treatment after correct diagnosis. Though numerous etiological factors have been proposed for these diseases, their true etio-pathogenesis is not yet established and therefore all therapies are palliative and none is effective universally. In light of this, the role of nitric oxide as a mediator in the etio-pathogenesis of these diseases was considered. The present study was undertaken to note the salivary nitric oxide levels as measured through its product nitrite in oral mucosal diseases like lichen planus and recurrent aphthous ulcers and also to ascertain whether salivary nitric oxide level has a role to play as a pathophysiological mediator in these diseases