Avaliação do perfil da imunoexpressão de 5-metilcitosina e 5-hidroximetilcitosina em parâmetros clínico-patológicos da queilite actínica e do carcinoma espinocelular de lábio

Abstract

Introduction: Actinic cheilitis (AC) is a potentially malignant disorder located on the lip caused by intense exposure to ultraviolet radiation (UV). It generates changes such as DNA methylation, associated with the process of carcinogenesis of neoplasms such as lip squamous cell carcinoma (CECLS). Both 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are epigenetic DNA alterations that affect gene expression, favoring the progression of CECLSs. 5mC and 5hmC are considered potential biomarkers in the development of some cancers, but their relationship in CECLS and AK celTLS is unknown. Therefore, studies are needed to elucidate the influence of these markers on CECLS carcinogenesis. Objectives: This research aims to evaluate the impact of 5mC and 5hmC on lip carcinogenesis, correlating clinical, histological, and immunohistochemical parameters in ACs and CECLSs. Material and Methods: For this, 15 samples of healthy lips, 30 of QAs, and 45 of CECLS s from the tumoral front will be selected, which were prepared by Tissue Micro Array (TMA), on a single block for immunohistochemical reactions (5hmC, 5mC). The collection of clinical data and histopathological grading of epithelial dysplasia in ACs were performed using the binary system and the system Bryne established for SCCTLS. Data will be expressed as mean and standard deviation and compared by Mann-Whitney and Kruskal-Wallis/Dunn, Wilcoxon and Spearman correlation tests (SPSS, p<0.05). Results: In the evaluation of CECL samples (n=45), a statistically significant difference (p<0.001) was observed in relation to 5mC labeling, which was higher than that of 5hmC. Additionally, in tumor lesions with T1/2 and T3/4 staging, a greater presence of 5mC was noted compared to 5hmC. Both male (p<0.001) and female (p=0.003) patients exhibited higher levels of 5mC when compared to 5hmC. Conclusions: There is expression of 5mC and 5hmC in QA and in CECL. 5mC appears to be related to CECL, although further studies are needed to assess its viability as a predictive biomarker for CECL in preserving QA lesions.