[Clinical significance of microtubule-associated protein 1 light chain 3 and mammalian target of rapamycin expression in oral leukoplakia in smokers and never-smokers].

OBJECTIVE: This study aimed to investigate the expression patterns and relationship of microtubule-associated protein 1 light chain 3 (LC3B) and mammalian target of rapamycin (mTOR) in oral leukoplakia (OLK) in smokers and never-smokers. This work also analyzed the relationship between smoking and the carcinogenic potential of OLK. METHODS: Immunohistochemistry was used to detect the expression of LC3B and mTOR in 120 patients with OLK. Clinical data from 120 smokers and never-smokers with OLK were analyzed. Subsequently, the relationships among LC3B and mTOR expression, clinical factors, and smoking were analyzed. RESULTS: Smoking and nonsmoking patients with OLK differed in terms of gender, age, lesion location, pathological typing, and carcinogenic situation. The positive rate of LC3B in never-smokers was higher than that in smokers. Whereas the positive rate of mTOR in smokers was higher than that in the corresponding never-smokers, and the differences were statistically significant (P<0.05). Smoking was positively correlated with the positive rate of mTOR (P<0.05), and had no significant correlation with LC3B expression. The positive rates of LC3B and mTOR were negatively correlated with the intensity of smoking (P<0.05). CONCLUSIONS: The effect of smoking habits on OLK may be linked to the expression of proteins that are directly associated with autophagy.