RESUMO
INTRODUCTION: Lung cancer is the leading cause of cancer mortality worldwide; therefore, understanding the biological or clinical role of tumor-associated antigens and autoantibodies is of eminent interest for designing antitumor immunotherapeutic strategies. METHODS: Here we prospectively analyzed the serum frequencies of New York esophageal squamous cell carcinoma 1 (NY-ESO-1), human epidermal growth factor 2/neu, and melanoma-associated antigen A4 (MAGE-A4) antibodies and expression of the corresponding antigens in tumors of 121 patients with NSCLC undergoing an operation without prior neoadjuvant chemotherapy and compared them with those in 57 control age-matched patients with no history of a malignant disease. RESULTS: We found that only antibodies specific for NY-ESO-1 (19.8% [n = 24 of 121]) were significantly increased in the group of patients with NSCLC compared with in the controls. NY-ESO-1 seropositivity was significantly positively associated with an active smoking history in patients with NSCLC but not in smokers from the control group. In tumors, the frequency of NY-ESO-1 mRNA expression was 6.3% (in four of 64 patients), the frequency of human epidermal growth factor 2/neu (HER 2/neu) expression was 11.9% (five of 42), and the frequency of MAGE-A4 expression was 35.1% (20 of 57). MAGE-A4 expression in tumors correlated with smoking status and male sex in patients with NSCLC. Patients with squamous cell carcinoma displayed higher expression of NY-ESO-1 and MAGE-A4 in tumors than did patients with adenocarcinoma. On the other hand, 94.7% of nonsmoking patients in our study had adenocarcinoma (of whom 73.7% were women). CONCLUSION: These results confirm the reported high immunogenicity of NY-ESO-1 and suggest that a smoking-induced chronic inflammatory state might potentiate the development of NY-ESO-1-specific immune responses. Moreover, smoking might contribute to the expression of other cancer/testis antigens such as MAGE-A4 at early stages of NSCLC development.
