Expressão imuno-histoquímica do ativador de plasminogênio do tipo uroquinase e seu receptor em carcinoma epidermoide de língua oral e sua relação com parâmetros clínico-patológicos

Abstract

Squamous cell carcinoma (SCC ) is the most common malignancy of the oral cavity (OSCC), with a high mortality rate. Due to this, the discovery of biomarkers that facilitate the understanding of the biological behavior of the tumor and improve treatment is necessary. Urokinase type plasminogen activator (uPA) and its receptor, uPAR, are responsible for the proteolysis of structures of the basement membrana and extracellular matrix, facilitating tumor invasion. This study aims to assess the immuno expression of these proteins in 46 cases of squamous cell carcinoma of the oral tongue (OTSCC). These results were related to the presence of metastasis, clinical TNM staging, locoregional recurrence, outcome of the lesion and histological grading. Immunostaining of each case was evaluated semiquantitatively, in the front of invasion and center of the tumor, in which scores were assigned: 0 (0% of positive cells), 1 (1-10% of positive cells), 2 (11 -50% positive cells) and 3 (more than 50% positive cells). The expression of uPA was observed in 93.5% (n=43) of the cases in the front of invasion, with predominance of score 2 (n=16; 34.8%) and in 67.9% (n=31) of the cases in the center of the tumor, with predominance of score 1 (n=15; 32.6%). Overall, the immunoexpression of uPA was not associated with clinical parameters. Regarding the malignant histological grading, a higher expression of uPA was observed in cases of high-grade malignancy comp ared to low-grade malignancy (p=0.05). Regarding the morphological parameters, increased expression of uPA was observed in the worst mode of invasion (p=0.03 ). The expression of uPAR was observed in 73.9% of cases in the front of invasion, with a predominance of score 1 (n=21; 45.6 %), and in 47.5% (n=21) of the cases in the center of the tumor, with a predominance of score 0 (n=25; 54.4%). Although no statistical differences were observed in relation to lymph node metastasis, clinical TNM staging, outcome, and histological grading, there was a higher expression of uPAR in cases with locoregional recurrence (p=0.04). Regarding the tumor intra -localization, it was observed an increased expression of uPA and uPAR at the front of invasion in relation to the center of the tumor (p<0.001). Regarding the correlation between uPA and uPAR, there was no statistical sign ificance. Based on these results, it is suggested that uPA and uPAR are involved in the progression of CELO, mainly in the deeper region of the tumor.