Evaluation of Cellular Changes and Immunohistochemistry Expression of p53 and p16 in the Oral Mucosa Among Saudi Smokers

Abstract

Background: Smoking is a well-known risk factor for various health problems, including oral cancer. P16 and P53 proteins are involved in cell cycle regulation and proliferation, and their expression levels can provide insights into cellular health. Objective: This study aims to evaluate the cellular changes and immunohistochemistry expression of p53 and p16 in the oral mucosa among Saudi smokers. Method: In a cross-sectional study obtained by scraping the buccal mucosa, 1000 samples were collected from 2022 to 2023. All of the study's participants were Saudi citizens of both genders. Seven hundred cigarette smokers and 300 nonsmokers made up the controls, using two sampling techniques: initially purposive and then snowball sampling. The materials were subjected to immunohistochemical analysis for P16 and P53 protein overexpression. The samples were scored based on the percentage of positively stained cells and staining intensity. The data were analyzed using SPSS, and categorical variables were identified as frequencies and percentages using the chi-squared test; a value of (P<0.05) was considered significant. Result: Cigarette smokers demonstrate significantly higher rates of cytological inflammation, reverse cytological infection, atypia, and binucleated/multinucleated cells compared to nonsmokers, with an overall abnormal result rate of 46% versus 18.7%, respectively (P=0.024). The study found higher P53 and P16 expression among smokers (7.14% and 2.14%, respectively) compared to nonsmokers (0.1% and 0.33%) (P=0.038). No significant differences were observed in P53/P16 expression across age groups (P=0.72) or between male and female participants (P=0.25). Conclusion: These findings highlight the detrimental effects of smoking on cellular health and reinforce the importance of smoking cessation in reducing the risk of developing cytological abnormalities and associated diseases. These results highlight the association of smoking with increased biomarker expression, emphasizing its relevance in understanding oral health risks.