Circulating anti-p53 antibodies in lung cancer and relationship to histology and smoking

Anti-p53 antibodies were examined in the plasma of 112 lung cancer patients by ELISA in order to study the distributions in lung cancer patients and the determinants of these antibodies in relation to lung cancer. Twenty (17.9%) lung cancer patients were found to have anti-p53 antibodies. The distribution of the antibodies by histological type was 7/48 (14.6%) adenocarcinoma, 8/32 (25.0%) squamous cell carcinoma, 3/7 (42.9%) small cell lung cancer, 0/4 large cell carcinoma, 0/8 adenosquamous cell carcinoma and 2/13 (15.4%) other types. By ethnicity, 8/44 (18.2%) Caucasians, 4/20 (20.0%) Hispanics and 8/48 (16.7%) African-Americans were positive for anti-p53 antibodies, with no significant differences among the groups (p = 0.5137). The antibody positivity rates were higher in lung cancer patients 55 years or older (21.2 %) than in the patients under 55 years (7.4%). The positive rates of the antibodies were 14.3% in non-smokers, 16.7% in ex-smokers and 19.1% in current smokers, with heavy smokers (≥41 pack-years) having the highest positive rate (28.6%), but none of these differences were statistically significant (p>0.05). Seven controls who had anti-p53 antibodies were all ex- smokers or current smokers and some had occupational exposures. No anti-p53 antibodies were found in 41 non-smoking controls. These results suggest that the development of anti-p53 antibodies in pulmonary carcinogenesis and its association with smoking and other carcinogenic exposures deserve further study.