Study on the expressions and clinical significances of p16~(INK4a) protein in 103 cases of non-small cell lung cancer

Objective To study the expressions and clinical significances of p16 INK4a protein in non-small cell lung cancer (NSCLC). Methods The expression of p16 INK4a protein was detected in 103 NSCLC samples by immunohistochemistry (S-P method), and 20 benign masses of lung as control.Results The negative expression of p16 INK4a was detected in 45 (43.69%) of 103 NSCLC cases. 58 cases showed positive immunohistochemical result. The negative rates of p16 INK4a expression in squamous cell carcinoma, adenocarcinoma, and bronchioloalveolar carcinoma samples were 58.82% (20/34), 39.39% (13/33) and 33.33% (10/36) respectively, and the significant difference was observed between the groups of squamous cell carcinoma and bronchioloalveolar carcinoma. Of the 65 samples analyzed from NSCLC patients, the negative rates of p16 INK4a expression were 35.14% (13/37) and 60.71% (17/28) in the groups of clinical stageⅠ+Ⅱ and Ⅲ+Ⅳ respectively. Its expression was closely related to clinical stage (P0.05).Conclusion The negative rate of p16 INK4a expression in squamous cell carcinoma was significantly higher than that in other pathological types, it indicated that expression alteration of INK4a gene had the tendency of histopathological specificity. Patients with higher clinical stages tended to show significantly higher negative rate of p16 INK4a expression, it was suggested that evaluation of p16 INK4a expression in NSCLC might be useful as a prognostic factor.