Freitas, Roseana de AlmeidaSouza Júnior, Orlando Felipe de2025-01-152025-01-152024-12-18SOUZA JÚNIOR, Orlando Felipe de. Estudo imunoistoquímico das proteínas e-caderina e n-caderina em carcinoma de células escamosas de lábio inferior. Orientador: Roseana de Almeida Freitas. 2024. 51f. Trabalho de Conclusão de Curso (Graduação em Odontologia) - Departamento de Odontologia, Universidade Federal do Rio Grande do Norte, Natal, RN, 2024.https://repositorio.ufrn.br/handle/123456789/61231Based on the search for biomarkers that contribute to a better understanding of the biological behavior of oral squamous cell carcinoma, this study aimed to analyze the immunostaining pattern of E-cadherin and N-cadherin proteins in lower lip squamous cell carcinomas (LLSCC). Twenty-five cases of LLSCC from patients treated at the Liga Norte Riograndense Contra o Câncer were selected. Clinical data were collected from patient records and histological slides were obtained for morphological study based on the BD histopathological grading system and immunohistochemistry based on qualitative and semiquantitative analysis of the immunoexpression of E-cadherin and N-cadherin proteins. Our sample showed a predominance of male individuals (72%), history of sun exposure (30%), and smoking and alcohol habits (68%). Tumors were diagnosed more often in stage II (48%) and showed a significant association with a high depth of invasion (p = 0.042). Immunohistochemical analysis revealed that most cases showed low membrane expression of E-cadherin at the invasion front (76%) and a slight predominance of high cytoplasmic expression (52%). A statistically significant association was observed between low membrane expression of this protein and tumor buds Regarding the immunoexpression of N-cadherin, high cytoplasmic expression was observed in most cases (60.0%), with no statistically significant associations found between membrane and cytoplasmic immunoexpression of N-cadherin (p > 0.05) and the morphological data. The findings confirm the existence of cadherin exchange in LLSCC and also the impact of E-cadherin dysregulation on the aggressiveness of these tumors. Keywords: epithelial-mesenchymal transition; chaderin; oral squamousAttribution-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nd/3.0/br/Transição epitélio-mesenquimalCaderinasCarcinoma epidermoidebachelorThesis