Stability of acetaldehyde-derived DNA adduct in vitro.
Acetaldehyde (AA) derived from alcoholic beverages is a confirmed carcinogen for esophageal and head and neck cancers. AA forms various DNA adducts and is thought to play a crucial role in carcinogenesis. Transient DNA adducts are usually repaired, but the stability of AA-derived DNA adducts has not been elucidated. We investigated the stability of N(2)-ethylidene-2'-deoxyguanosine (N(2)-ethylidene-dG), a major AA-derived DNA adduct, in cultured cells. First, to determine the optimal concentration of AA for detecting N(2)-ethylidene-dG in cell culture, a dose-response study was performed using HL60 cells of the human promyelocytic leukemia cell line. An AA concentration ≥ 0.01% (1.8 mM) was required to detect N(2)-ethylidene-dG in vitro. We next examined the stability of N(2)-ethylidene-dG. After a 1 or 2h exposure to 0.01% of AA in a tightly sealed bottle, N(2)-ethylidene-dG content was measured by sensitive liquid chromatography tandem mass spectrometry immediately, 24h, and 48 h after exposure. After the 1h exposure, the mean (± SD) N(2)-ethylidene-dG contents were 12.1 ± 1.28, 8.20 ± 0.64, and 6.70 ± 0.52 adducts per 10(7) bases at each postexposure time. After the 2h exposure, N(2)-ethylidene-dG content increased to 21.4 ± 7.50, 10.5 ± 3.61, and 9.83 ± 3.90 adducts per 10(7) bases at each postexposure time. The half-life of this adduct was calculated as ∼35 h in independent experiments. These results indicate that AA exposure from daily alcohol consumption may cause DNA damage and may increase the risk of alcohol-related carcinogenesis.
Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, 54 Shogoin-kawaharacho, Sakyo-ku, Kyoto 606-8507, Japan.
Kimiko
K
Hori
Shin'ichi
S
Miyamoto
Yoshiyuki
Y
Yukawa
Manabu
M
Muto
Tsutomu
T
Chiba
Tomonari
T
Matsuda
D000079:Acetaldehyde / Q000737:chemistry / Q000378:metabolism*; D002273:Carcinogens / Q000737:chemistry / Q000378:metabolism*; D018929:Cell Culture Techniques; D002471:Cell Transformation, Neoplastic / Q000139:chemically induced; D018736:DNA Adducts / Q000737:chemistry / Q000378:metabolism*; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism; D018922:HL-60 Cells; D006207:Half-Life; D006801:Humans
D002273:Carcinogens; D018736:DNA Adducts; C525837:N2-ethylidene-2'-deoxyguanosine; D003849:Deoxyguanosine; D000079:Acetaldehyde