Cellular Alterations and Immunohistochemical Expression of p53 and p16 in the Oral Mucosa of Saudi Smokers: A Cross-Sectional Study

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. Several studies using different methods, like cytological assessment, DNA damage detection, and histological investigations, have looked at how cells change in the oral mucosa of smokers.

Objective: This study aims to evaluate the cellular changes and immunohistochemical expression of p53 and p16 in the oral mucosa among Saudi smokers.

Methods: From 2022 to 2023, 1000 samples from the buccal mucosa were collected in a cross-sectional study. All the participants included in the study's participants were Saudi citizens of both genders. Seven hundred cigarette smokers and 300 non-smokers made up the controls, using two sampling techniques: initially purposive and then snowball sampling. Both smokers and nonsmokers appeared to be in fair health, with ages ranging from 18 to 85 years. 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 (including the software version), and categorical variables were identified as frequencies and percentages using the chi-squared test; a value of P<0.05 was considered significant.

Results: This study is an investigation of the classification of participants based on gender and age group, as well as the cytopathological changes observed in cigarette smokers compared to nonsmokers. Cigarette smokers demonstrated significantly higher rates of cytological inflammation, reverse cytological infection, atypia, and binucleated/multinucleated cells compared to non-smokers, 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 non-smokers (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. This is a cross-sectional study which limited to establishing causality between smoking and the observed cytopathological changes. Future longitudinal studies are needed to examine whether these cellular changes persist over time and assess their impact on disease development.