Gender difference in DNA adduct levels among nonsmoking lung cancer patients

Lung cancer is the leading cause of cancer mortality in Taiwanese women. Ci garette smoking cannot explain the high lung cancer mortality in this popul ation because less than 10% of women in Taiwan are smokers. Therefore, envi ronmental Factors other than smoking may play an important role in lung can cer development in female nonsmokers. The purpose of this study was to eluc idate the role of environmental carcinogen exposure in lung cancer developm ent in Taiwanese female nonsmokers, based on DNA adduct Formation. We colle cted nontumorous lung tissues resected From 62 nonsmoking lung cancer patie nts and 20 noncancer controls to investigate whether differences in suscept ibility to DNA adduct formation exist between men and women. P-32-postlabel ing and ELISA (enzyme-linked immunosorbent assay) with polyclonal antibody against BPDE (7,81-dihydroxy-anti-9,10epoxy-7, 8,9,10-tetrahydrobenzo[a] py re ne)-DNA adduct were used to evaluate DNA adduct levels in lung tissues o f study subjects. Our data showed that the DNA adduct levels of lung cancer patients determined both assays were significantly higher than those of no ncancer controls (P = 0.0001 for P-32-postlabeling; P = 0.01 For ELISA). Mo reover, DNA adduct levels in females were markedly greater than those in ma les (P = 0.014 for P-32-postlabeling; P = 0.001 For ELISA). The difference in DNA adduct levels could not be explained by genetic polymorphisms of cyt ochrome P-4501Al (CYP1Al) or glutathione S-transferase (GSTM1), as determin ed by polymerase chain reaction and restriction fragment length polymorphis m. These results demonstrate that lung cancer patients have a higher suscep tibility to DNA damage than that of noncancer controls. In addition, differ ences in susceptibility to DNA damage derived From environmental carcinogen exposure were observed between male and Female nonsmokers. In conclusion, high susceptibility to DNA damage in Females may partially explain the high mortality rate of lung cancer in nonsmoking Taiwanese women. (C) 2001 Wile y-Liss, Inc.