title: Alcohol metabolism in human cells causes DNA damage and activates the Fanconi anemia-breast cancer susceptibility (FA-BRCA) DNA damage response network.
abstract: BACKGROUND
  We recently reported that exposure of human cells in vitro to acetaldehyde resulted in the activation of the Fanconi anemia-breast cancer susceptibility (FA-BRCA) DNA damage response network.
  
  
  METHODS
  To determine whether intracellular generation of acetaldehyde from ethanol metabolism can cause DNA damage and activate the FA-BRCA network, we engineered HeLa cells to metabolize alcohol by expression of human alcohol dehydrogenase (ADH) 1B.
  
  
  RESULTS
  Incubation of HeLa-ADH1B cells with ethanol (20 mM) resulted in acetaldehyde accumulation in the media, which was prevented by co-incubation with 4-methyl pyrazole (4-MP), a specific inhibitor of ADH. Ethanol treatment of HeLa-ADH1B cells produced a 4-fold increase in the acetaldehyde-DNA adduct and N(2)-ethylidene-dGuo and also resulted in the activation of the FA-BRCA DNA damage response network, as indicated by a monoubiquitination of FANCD2 and phosphorylation of BRCA1. Ser 1524 was identified as 1 site of BRCA1 phosphorylation. The increased levels of DNA adducts, FANCD2 monoubiquitination, and BRCA1 phosphorylation were all blocked by 4-MP, indicating that acetaldehyde, rather than ethanol itself, was responsible for all 3 responses. Importantly, the ethanol concentration we used is within the range that can be attained in the human body during social drinking.
  
  
  CONCLUSIONS
  Our results indicate that intracellular metabolism of ethanol to acetaldehyde results in DNA damage, which activates the FA-BRCA DNA damage response network.
authors.affiliation: Section on Molecular Neurobiology, Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, NIH, Rockville, Maryland, USA.
authors.forename: Jessy
authors.initials: J
authors.lastname: Abraham
authors.forename: Silvia
authors.initials: S
authors.lastname: Balbo
authors.forename: David
authors.initials: D
authors.lastname: Crabb
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Brooks
mesh_terms: D000079:Acetaldehyde / Q000378:metabolism*; D000426:Alcohol Dehydrogenase / Q000235:genetics / Q000378:metabolism; D019313:BRCA1 Protein / Q000378:metabolism*; D018736:DNA Adducts; D000431:Ethanol / Q000378:metabolism*; D052236:Fanconi Anemia Complementation Group D2 Protein / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans
chemical_list: D019313:BRCA1 Protein; D018736:DNA Adducts; D052236:Fanconi Anemia Complementation Group D2 Protein; D000431:Ethanol; C489332:ADH1B protein, human; D000426:Alcohol Dehydrogenase; D000079:Acetaldehyde