The efficiency of propranolol on occurrence and development of 4-nitroquinoline 1-oxide-induced squamous cell carcinoma of the tongue in rats

AIMS: The aim of this study to investigate the efficiency of propranolol on occurrence and development of 4-nitroquinoline 1-oxide (4NQO)-induced squamous cell carcinogenesis of the tongue in rats. SUBJECTS AND METHODS: The sample was composed of 27 male Sprague Dawley rats that received 50 ppm 4NQO for 20 weeks in drinking water. Group 1 (n = 9) was treated with 50 mg/kg/day propranolol for 20 weeks, Group 2 (n = 9), after carcinogenesis inducement for 20 weeks, received propranolol (50 mg/kg/day) for 2 weeks and Group 3 (n = 9) received no treatment. At the end of the experimental stage, the tongue specimens were evaluated under a light microscope and categorized as low- or high-risk lesions according to a binary system. STATISTICAL ANALYSIS USED: The statistical comparison was performed with a likelihood ratio test. RESULTS: Histopathological analysis revealed the risk of malignant transformation rates as 33.3% in Group 1, 55.5% in Group 2 and 77.8% in Group 3; however, the difference between the groups was not statistically significant (P > 0.05). CONCLUSION: The results of the study suggest that propranolol has a tendency to preventive effect against carcinogenesis.