Study of the effects caused by chronic smoking in oral mucosa cells

Abstract

The objective of this study is to evaluate the early stages of oral carcinogenesis, established by histochemical methods, immunohistochemical and molecular techniques. The sample will consist of four groups. Group one will consist of smokers histopathologically diagnosed with squamous cell carcinoma, group two chronic smokers, group three individuals treated smoking cessation in abstinence for one year and group four nonsmokers. From each patien, two buccal smears will be collected using the cytobrush on floor of the mouth bilaterally and processed for the Papanicolaou. Four samples of cytological material from tongue mucosa bilaterally for PCR, and two smears for immunohistochemistry. For groups 2 and 3, the evaluation of smoking will be supplemented with data from the Fagerstrom score for the degree of nicotine dependence and concentration of carbon monoxide exhaled air through the mini-Smokerlyzer equipment. Samples will be evaluated using the criteria of Papanicolaou and Traut for analysis of epithelial maturation, quantitative RT-PCR for gene expression analysis of MLH1, MSH2, ATM and ATP6V1C, and immunohistochemistry for the expression of corresponding proteins. Analysis of the data obtained to evaluate the maturation of epithelial cells by the Papanicolaou method will be descriptive. Statistical analyzes of the data obtained by PCR will be performed using the software package STATA 11 (StataCorp LP, Texas, USA). For other evaluations, parametric data will be treated by statistical tests using analysis of variance (ANOVA) and the non-parametric by Kruskal-Wallis test and Mann-Whitney test. (AU)