EVALUATION OF THE IMMUNOEXPRESSION OF YES-ASSOCIATED PROTEIN (YAP) IN HYPERCERATOSES AND ORAL EPITHELIAL DYSPLASIAS
Oral leukoplakia; Erythroplasia; Immunohistochemistry; Carcinogenesis.
Lesions clinically diagnosed as leukoplakia, erythroplasia or leukoerythroplasia fall into the group of oral potentially malignant disorders (OPMDs), which histopathologically may exhibit findings ranging from hyperkeratosis, through oral epithelial dysplasias (OEDs) to oral squamous cell carcinoma (OSCC). Even with countless efforts in the last decades, the evaluation of morphological criteria remains the main way of trying to predict the risk of malignant transformation of these lesions, and the demand for a biomarker that helps in this predictive scheduling represents an important implement that can provide greater chances of early treatment for patients affected by OPMDs. This study aims to evaluate the immunoexpression of Yes-Associated Protein (YAP) in oral lesions clinically diagnosed as leukoplakia, erythroplasia or leukoerythroplasia and histopathologically as hyperkeratosis or oral epithelial dysplasia, correlating this immunoexpression with the degree of histopathological severity of these lesions, aiming to assist in its risk stratification. The sample will consist of 20 cases of hyperkeratosis (lesions with no dysplasia), 60 cases of oral epithelial dysplasia (20 mild, 20 moderate and 20 severe) and 10 cases of normal oral mucosa (control group). The clinical and epidemiological data of these patients will also be collected. To assess the degree of dysplasia, the WHO gradations will be used (EL-NAGGAR et al., 2017), followed by the Binary System (KUJAN et al., 2006). For the analysis of the immunohistochemical profile of the YAP protein, the following features will be evaluated: intra-cellular location, the number of marked cells and their distribution in the epithelial tissue (XIAO et al., 2014). For the analysis between clinical, histopathological parameters and YAP immunoexpression, Pearson's chi-square and Fisher's exact tests will be performed. For all analyzes, the significance level of 5% will be considered, with p values ≤ 0,05 being considered significant.