This study focused on investigating the roles of p16INK4a, p14ARF, and p53 proteins in the development of squamous cell carcinoma of the lip. A total of 46 tissue samples were analyzed, which included 19 cases of squamous cell carcinoma of the lip, 14 cases of actinic cheilitis, and 13 samples of normal lip mucosa. The study also evaluated protein expression in the epithelial tissue surrounding the tumors. Notably, p16INK4a levels were significantly higher in actinic cheilitis compared to normal mucosa (P = 0.001). p14ARF expression increased progressively from normal mucosa to actinic cheilitis (P = 0.001) but decreased significantly during the transition from actinic cheilitis to carcinoma (P = 0.003). For p53, its expression levels increased from normal mucosa to actinic cheilitis (P = 0.001) and further increased in carcinoma cases (P = 0.008). In addition, a positive correlation was observed between p14ARF and p53 in the epithelium adjacent to the carcinoma. This study concluded that while p16INK4a and p14ARF expression levels can reflect certain stages, they are not definitive markers for predicting the progression of actinic cheilitis into carcinoma. Despite the activation of the p14ARF/p53 pathway in the surrounding epithelial tissue, it seems insufficient to prevent the development of cancer.
