Expression and clinical significance of Fas,FasL and Caspase-3 in lung cancer

Objective:To investigate the expression and significance of Fas,FasL and Caspase-3 in lung cancer and explore the mechanism of tumor immune evasion.Methods: Immunohistochemical SP method was used to examine the expression of Fas,FasL and Caspase-3 in 52 cases of lung cancer and 18 cases of normal epithelium tissue of tunica mucosa bronchiorum.Results: The positive expression rates of Fas,FasL and Caspase-3 were significantly lower in lung cancer than in normal epithelium tissue of tunica mucosa bronchiorum(P0.01).The positive expression of Fas,FasL and Caspase-3 were different,though insignificantly,between squamous cell carcinoma and adenocarcinoma.The positive expression of Fas and Caspase-3 in NSCLC were significantly higher than that in SCLC(P0.05).The positive expression rates of FasL in NSCLC and SCLC were 59.18%(29/49) and 33.33%(1/3) respectively,there was no significant difference between them(P0.05).The positive expression of Fas,FasL and Caspase-3 in lung cancer were associated with pathological grade(P0.05),but none of them had any correlation with local lymph node metastases or TNM stages.There was no correlation between Fas expression and FasL expression in lung cancer,and had the same result between Fas and Caspase-3,or FasL and Caspase-3.Conclusion: Down-regulation of Fas,FasL and Caspase-3 may contribute to the carcinogenesis and development of lung carcinoma by evading the host immune surveillance.