ANALYSIS OF THE IMMUNOHISTOCHEMICAL EXPRESSION OF T-BET AND IFN-GAMMA IN SQUAMOUS CELLS CARCINOMAS OF LOWER LIP AND ORAL TONGUE
Squamous Cell Carcinoma; Immunohistochemistry; Interferon-gamma, Th1 cells.
Oral squamous cell carcinomas (OSCC) are among the eight most common cancers in the world, presenting distinct behaviors according to anatomical location and age. Lower lip squamous cell carcinomas (LLSCC) are less aggressive, with lower rates of relapse and mestastasis than oral tongue squamous cell carcinomas (OTSCC). In this research, 57 OSCC cases were evaluated, 27 of lower lip and 30 of oral tongue of the Service of Oral Pathology of the Federal University of Rio Grande do Norte, being classified according to the histological grading of malignancy of the World Health Organization (WHO) and subsequently submitted to the immunohistochemistry process being the T-Bet evaluated quantitatively and the IFN-γ evaluated semi-quantitatively in both the parenchyma and in the stroma of the OSCC. We found that the LLSCC were classified as well differentiated, while the moderately differentiated OTSCC were the most evidenced. Immunohistochemical analysis revealed strong cytoplasmic and nuclear labeling for T-Bet and IFN-γ both in the parenchyma and in the stroma of the OSCC. In this study, T-Bet immunoexpression was higher in OTSCC, with the stromal of these carcinomas being the dentent of the largest numbers of immunoreactive cells, especially in moderately differentiated OSCC. During the evaluation of IFN-γ immunoexpression a greater expression was observed in LLSCC, especially in well-differentiated OTSCC. The research data suggest different alterations in the LLSCC and OTSCC tumor microenvironments, in which in the OTSCC an inhibition of the activity of T-Bet-labeled cells with lower expression of IFN-γ in relation to LLSCC is evidenced, concluding that the Th1 is present in both OTSCC and LLSCC, with Th1 being more efficient in LLSCC.