Does YAP influence cell proliferation and apoptosis in benign epithelial odontogenic lesions?

OBJECTIVE: To analyze the immunohistochemical expression of YAP and its correlation with markers involved in cell proliferation and apoptosis in benign epithelial odontogenic lesions. STUDY DESIGN: The sample consisted of 95 cases of odontogenic lesions (25 dentigerous cysts, 30 non-syndromic odontogenic keratocysts, 30 conventional ameloblastomas, and 10 unicystic ameloblastomas) and 10 dental follicles used as normal odontogenic tissue. The histological sections were submitted to immunohistochemistry with YAP, cyclin D1, Ki-67, and Bcl-2 antibodies. Immunoexpression was analyzed qualitatively and quantitatively using an adapted method. The collected data were analyzed descriptively and statistically (p ≤ 0.05). RESULTS: The highest YAP expression was observed in odontogenic keratocysts, followed by unicystic ameloblastomas and conventional ameloblastomas, which exhibited moderate immunoreactivity predominantly in peripheral cells. Furthermore, significant differences in YAP immunoexpression were observed between the groups analyzed, with significant positive correlations between YAP and cyclin D1 in dentigerous cysts and unicystic ameloblastomas and between YAP and Ki-67 in unicystic ameloblastomas (p < 0.05). However, there were no statistically significant correlations between YAP and Bcl-2 immunoexpression in the groups studied. CONCLUSION: YAP may influence epithelial cell proliferation in odontogenic cysts and tumors, suggesting its possible participation in the progression of the odontogenic lesions studied.

Perfil imuno-histoquímico de marcadores associados à transição epitelial-mesenquimal em lesões odontogênicas epiteliais benignas / Immunohistochemical profile of markers associated with epithelial-mesenchymal transition in benign epithelial odontogenic lesions

Os cistos e tumores odontogênicos, lesões que acometem o complexo maxilomandibular, podem exibir comportamento clínico-biológico mais agressivo. E a transição epitelialmesenquimal (TEM), processo pelo qual as células epiteliais perdem propriedades fenotípicas e adquirem características de células mesenquimais, incluindo maior motilidade e capacidade de invasão, através da regulação de fatores centrais de transcrição e suas vias associadas, podem fazer parte de características associadas às lesões odontogênicas. Dessa forma, o presente trabalho buscou analisar e comparar a expressão imuno-histoquímica de proteínas (Zeb1, Ecaderina, N-caderina e vimentina) envolvidas no processo de TEM, em lesões odontogênicas epiteliais benignas. A amostra consistiu em 88 casos de lesões odontogênicas, das quais compreendem 28 casos de ameloblastoma (AB), 30 de ceratocisto odontogênico (CO) e 30 de cisto dentígero (CD). Todos os espécimes submetidos à técnica imuno-histoquímica foram avaliados por microscopia de luz, e submetidos à escolha aleatória de 5 (cinco) campos, os quais foram fotografados em um aumento de 400x. A avaliação da expressão de cada marcador, a partir da análise em seu compartimento celular específico, foi feita de forma semiquantitativa, através da multiplicação dos escores associados à porcentagem de células imunomarcadas pelos escores relacionados à intensidade da coloração, sendo feita uma média dos cinco campos e o resultado definido como baixa expressão ou alta expressão, conforme metodologia utilizada. As associações foram feitas através do teste de Qui-quadrado e as correlações através do teste de correlação de Spearman. O nível de significância foi estabelecido em 5% (p < 0,05). Os resultados mostraram um pico de prevalência entre a 2ª e 3ª décadas de vida, em todas as lesões estudadas, com um acometimento maior em região posterior de mandíbula, e os ABs foram as lesões de maiores tamanhos, com 65% medindo acima de 2,5cm. A imuno-histoquímica evidenciou baixa expressão de Zeb1 em epitélio odontogênico das lesões estudadas, alta expressão de E-caderina e N-caderina, e uma expressão intermediária de vimentina. Quando realizada a correlação entre os marcadores, observou-se nos casos de AB uma correlação positiva e moderada entre Zeb1 nuclear e E-caderina membranar, Zeb1 citoplasmática e E-caderina membranar e entre E-caderina e vimentina citoplasmáticas. Como também uma correlação positiva moderada, nos casos de CD, entre Zeb1 nuclear e vimentina citoplasmática, e entre Zeb1 e vimentina citoplasmáticas. Logo, podemos concluir que Zeb1 pode estar atuando indiretamente nas vias responsáveis pelo crescimento e características morfológicas dessas lesões estudadas. Além disso, a expressão diferencial de E-caderina, Ncaderina e vimentina demonstraram fazer parte de um processo de TEM parcial nas lesões odontogênicas epiteliais benignas estudadas (AU).

Odontogenic cysts and tumors, lesions that affect the maxillomandibular complex, may exhibit a more aggressive clinical-biological behavior. And the epithelial-mesenchymal transition (EMT), a process by which epithelial cells lose phenotypic properties and acquire characteristics of mesenchymal cells, including increased motility and invasiveness, through the regulation of central transcription factors and their associated pathways, may be part of characteristics associated with odontogenic lesions. Thus, the present work sought to analyze and compare the immunohistochemical expression of proteins (Zeb1, E-cadherin, N-cadherin and vimentin) involved in the MET process in benign epithelial odontogenic lesions. The sample consisted of 88 cases of odontogenic lesions, comprising 28 cases of ameloblastoma (AB), 30 of odontogenic keratocyst (CO) and 30 of dentigerous cyst (CD). All specimens submitted to the immunohistochemical technique were evaluated by light microscopy and submitted to the random choice of 5 (five) fields, which were photographed at a magnification of 400x. The evaluation of the expression of each marker, based on the analysis in its specific cellular compartment, was carried out in a semi-quantitative manner, through the multiplication of the scores associated with the percentage of immunostained cells by the scores related to the intensity of staining, with an average of the five fields and the result defined as low expression or high expression, according to the methodology used. The associations were made using the chi-square test and the correlations using the Spearman correlation test. The significance level was set at 5% (p < 0.05). The results showed a prevalence peak between the 2nd and 3rd decades of life, in all the lesions studied, with a greater involvement in the posterior region of the mandible, and the ABs were the largest lesions, with 65% measuring above 2, 5cm. Immunohistochemistry showed low expression of Zeb1 in the odontogenic epithelium of the lesions studied, high expression of E-cadherin, high expression of N-cadherin and an intermediate expression of vimentin. When the correlation between the markers was performed, a positive and moderate correlation was observed in the cases of AB between nuclear Zeb1 and membrane E-cadherin, cytoplasmic Zeb1 and membrane E-cadherin and between cytoplasmic E-cadherin and vimentin. As well as a moderate positive correlation, in CD cases, between nuclear Zeb1 and cytoplasmic vimentin, and between cytoplasmic Zeb1 and vimentin. Therefore, we can conclude that Zeb1 may be acting indirectly on the pathways responsible for the growth and morphological characteristics of these lesions studied. Furthermore, the differential expression of E-cadherin, N-cadherin and vimentin was shown to be part of a partial TEM process in the benign epithelial odontogenic lesions studied (AU).

YouTube™ and oral lichen planus: an appraisal of the educational quality of information.

The objective of this study was to analyze the quality of videos on oral lichen planus (OLP) available in YouTube™. A cross-sectional analytical study was conducted by searching the video sharing platform YouTube™. Videos aimed at clarifying the etiological and clinical characteristics, diagnostic criteria, treatment, and prognosis of OLP were included. A total of 481 videos were retrieved and 37 were included in the study according to the selection criteria established. Most of the videos evaluated (86.5%; n = 32) were produced by independent users. The average reliability was 1.8 and quality assessment classified only three videos (8.1%) as having good/excellent quality. A significant correlation was observed between the length of the video analyzed and its quality and reliability (p < 0.05), as well as between the reliability and usefulness of the video (p = 0.03). YouTube™ has become a leading source of information for the general population. However, a significant number of these videos have a low quality. Students, professionals, and healthcare providers must be more actively involved in providing clear, accurate, and reliable evidence-based information in an accessible language in order to enable significant improvement in patient care delivery.