Immunohistochemical quantitation of 4-aminobiphenyl-DNA adducts and p53 nuclear overexpression in T1 bladder cancer of smokers and nonsmokers

Abstract

An immunoperoxidase method, using a monoclonal antibody which recognizes 4-aminobiphenyl (4-ABP)-DNA adducts, was developed for the detection and quantitation of DNA damage in bladder tissue and applied to stored paraffin blocks of transurethral resection specimens of 46 patients with T1 bladder cancer. Mean relative staining intensity for 4-ABP-DNA adducts was significantly higher in current smokers (275 +/- 81, n = 24) compared to nonsmokers (113 +/- 71, n = 22) (P < 0.0001). There was a linear relationship between mean levels of relative staining and number of cigarettes smoked with lower levels in the 1-19 cig/day group (205 +/- 30, n = 5), compared to the 20-40 (289 +/- 40, n = 7) and the >40 cig/day group (351 +/- 57, n = 3)(P < 0.001). Nuclear overexpression of p53, analyzed by immunoperoxidase staining, was observed in 27 (59%) of the 45 stage T1 tumors analyzed. There was a significant correlation between p53 overexpression and recurrence of disease (odds ratio = 12.3, P < 0.01). Nuclear staining of p53 was also correlated with smoking status, cig/day and 4-ABP-DNA adducts. This work demonstrates that the immunohistochemical method has sufficient sensitivity for detection of 4-ABP-DNA adducts in human bladder samples. The method has several advantages including small sample size, the possibility of retrospective analysis of stored paraffin blocks, the ability to analyze binding in specific cell types, and a relatively low cost.

p53 Expression and Environmental Tobacco Smoke Exposure in Feline Oral Squamous Cell Carcinoma

“…Unlike the protective effect seen with other variables, the association between p53 overexpression and ETS seems a logical one because human tumors associated with both direct and indirect exposure to tobacco carcinogens are frequently found to overexpress p53. 6,9 Studies in human populations have demonstrated the presence of DNA adducts with tobacco-related carcinogens in neoplasms associated with tobacco use, as well as in the oral mucosal cells of cancer-free tobacco users. 6,8,12 Similar studies would need to be conducted in feline populations to establish or deny a causative role for ETS.…”

“…6,9 Studies in human populations have demonstrated the presence of DNA adducts with tobacco-related carcinogens in neoplasms associated with tobacco use, as well as in the oral mucosal cells of cancer-free tobacco users. 6,8,12 Similar studies would need to be conducted in feline populations to establish or deny a causative role for ETS. It must also be considered that the ETS may alone not be causal but a key exposure in a series of cumulative genomic insults.…”

“…10 p53 has also been found to be overexpressed in human tumors linked to carcinogens found in tobacco products, particularly oral SCC. 6,[8][9][10] Furthermore, p53 mutations in conjunction with 4-ABP adducts have been demonstrated in human oral SCC and transitional cell carcinoma of the bladder, 6,8 im-plying a role for tobacco-mediated mutation of the p53 gene.…”

Genetic susceptibility to tobacco-related cancer

“…Similar linear relationship was also found in bladder cancer biopsies. Immunohistochemistry analysis of human bladder biopsies with an antibody specific to 4-aminobiphenyl (4-ABP)-DNA adducts detected a correlation with staining levels and smoking history (Curigliano et al, 1996). Adduct levels were significantly higher in current smokers (n ¼ 24) than in nonsmokers (n ¼ 22) (Po0.0001).…”

Consumption of Raw Cruciferous Vegetables is Inversely Associated with Bladder Cancer Risk

“…In fact, our preliminary study showed that certain dietary isothiocyanates could inhibit the formation of 4-aminobiphenyl-DNA adducts in human bladder cancer cells. 4-Aminobiphenyl, a major carcinogen of human bladder cancer derived from cigarette smoking as well as occupational exposure, causes DNA damage and tumorigenic transformation in the bladder (33)(34)(35)(36), and indeed, 4-aminobiphenyl-DNA adducts were detected in a large percentage of human bladder cancer biopsies and were closely correlated to the amount of cigarettes smoked (37)(38)(39). Thus, it is possible that dietary isothiocyanates derived from cruciferous vegetables may be particularly effective in modifying smoking-related bladder carcinogenesis.…”