New insight into how alcohol is linked to breast and liver cancers

In collaboration with the Press Association

A US laboratory study has revealed how the breakdown of alcohol in human cells results in DNA damage that causes cell changes linked to cancer.

The study shows how researchers are homing in on the way alcohol is linked to several cancers, particularly breast and liver cancers.

Published in Alcoholism: Clinical & Experimental Research, the new research shows that when alcohol - specifically ethanol - is converted inside cells into a chemical called acetaldehyde, the resulting DNA damage triggers a collection of proteins known as the 'FA-BRCA network' to respond and coordinate DNA repair.

In the human body, the FA-BRCA network seems to be particularly important in protecting against breast cancer.

The research team used human cells engineered to produce an enzyme called alcohol dehydrogenase 1B (ADH1B) - which is found in liver and breast tissue - and exposed them to a concentration of alcohol designed to be similar to blood alcohol levels attained during social drinking.

The results confirmed that the ethanol was being converted to acetaldehyde, causing DNA damage and switching on the cell's DNA repair genes.

Study author Philip J Brooks, metabolism and health effects programme director at the National Institute on Alcohol Abuse and Alcoholism, said: "Although the link between drinking alcohol and certain types of cancers was first established in the 1980s the existence of such a relationship did not prove that alcohol itself caused the cancers.

"More recent evidence, however, has confirmed that alcohol - or more specifically, ethanol - is carcinogenic to humans at several sites in the body."

Of the new study, Dr Brooks said: "We found that the cells converted the alcohol into acetaldehyde, and that this resulted in increased levels of acetaldehyde-DNA damage.

"In addition, the cells responded by activating the FA-BRCA network, as measured by two different methods."

"Based on our research as well as more recent findings, it seems likely that the relationship between alcohol metabolism, the FA-BRCA network, and human health will become an increasingly important area of investigation in the future," he said.

The authors added: "While our work is consistent with a role for acetaldehyde in alcohol-related liver and breast cancer, more studies in animals and humans will be necessary to prove such a role."

Oliver Childs, senior science information officer at Cancer Research UK, said: "We've known for some time that alcohol is linked to several cancers, and it's likely that it causes different types of cancer in different ways.

"This work takes us a step closer to understanding one of the ways in which alcohol contributes to the development of breast and liver cancers - it will be interesting to see if this lab work translates into studies in people."

Copyright Press Association 2011

References

  • Abraham, J. et al. Alcohol metabolism in human cells causes DNA damage and activates the Fanconi Anemia–Breast Cancer Susceptibility (FA-BRCA) DNA damage response network. Alcoholism: Clinical & Experimental Research DOI: 10.1111/j.1530-0277.2011.01563.x