Tobacco smoke-associated N7-alkylguanine in DNA of larynx tissue and leucocytes.
The presence of N7-alkylguanine adducts in DNA was analysed in a group of 46 patients with larynx tumours. All patients were subjected to laryngectomy and the tissues accessible for analysis by (32)P-post-labelling assay were larynx tumour, larynx non-tumour and peripheral blood leucocytes. N7-Alkylguanine adducts were detected in all the studied DNA samples. The average level of N7-alkylguanines was 26.2/10(7) nucleotides in tumour cells, 22.7/10(7) in non-tumour cells and 13.1/10(7) in blood leucocytes. There was significantly higher level of N7-alkylguanines in the larynx tissues in males than in females. The effect of tobacco smoking on DNA adduct levels was shown by an increase in the average levels of N7-alkylguanines in the subject groups classified according to their smoking habits. A moderate age-related increase in levels of N7-alkylguanine was demonstrated in larynx tumour tissue. The levels of N7-alkylguanine adducts in larynx cells were compared with that of aromatic DNA adducts. Pearson correlation coefficients (0.28 for tumour tissue and 0.30 for non-tumour tissue) indicate independent formation and removal of N7-alkylguanine and aromatic DNA adducts resulting from tobacco smoke exposure.
Szyfter
K
K
Center for Nutrition and Toxicology, Karolinska Institute, Huddinge, Sweden.
Hemminki
K
K
Szyfter
W
W
Szmeja
Z
Z
Banaszewski
J
J
Pabiszczak
M
M
D000328:Adult; D000368:Aged; D000477:Alkylating Agents / Q000032:analysis*; D018736:DNA Adducts / Q000032:analysis*; D005260:Female; D006147:Guanine / Q000031:analogs & derivatives / Q000032:analysis*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000737:chemistry*; D007830:Larynx / Q000737:chemistry*; D007962:Leukocytes / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D010947:Plants, Toxic; D012906:Smoke; D014026:Nicotiana / Q000737:chemistry*
D000477:Alkylating Agents; D018736:DNA Adducts; D012906:Smoke; D006147:Guanine