How Alcohol Damages Stem Cell DNA and Increases Cancer Risk

By Reuters

LONDON–Drinking alcohol produces a harmful chemical in the body which can lead to permanent genetic damage in the DNA of stem cells, increasing the risk of cancer developing, according to research published on Wednesday.

Working with mice in a laboratory, British scientists used chromosome analysis and DNA sequencing to examine the genetic damage caused by acetaldehyde, a harmful chemical produced when the body processes alcohol.

Their findings offered more detail about how alcohol increases the risk of developing 7 types of cancer, including common forms such as breast and bowel cancer. It also showed how the body seeks to defend against the damage alcohol can do.

“Some cancers develop due to DNA damage in stem cells. While some damage occurs by chance, our findings suggest that drinking alcohol can increase the risk of this damage,” said Ketan Patel, a professor at the Medical Research Council Laboratory of Molecular Biology, who co-led the study.

The World Health Organization’s International Agency for Research on Cancer classifies alcohol as a Group 1 carcinogen, citing “convincing evidence” it causes cancer in humans.

A study published in 2011 found that alcohol is responsible for around 4 percent of all cancer in Britain – equating to around 12,800 cases a year.

In Wednesday’s study, published in the journal Nature, Patel’s team gave diluted alcohol to mice and then analyzed the effect on the animals’ DNA. They found that acetaldehyde can break and damage DNA within blood stem cells, permanently altering the DNA sequences within these cells.

This is important, Patel said, because when healthy stem cells become faulty, they can give rise to cancerous cells.

The researchers also looked at how the body tries to protect itself against damage caused by alcohol. The first line of defense is a group of enzymes called aldehyde dehydrogenases or ALDHs, Patel explained. These break down the acetaldehyde into acetate, which cells can then use as a source of energy.

In the study, when mice lacking a critical ALDH enzyme were given alcohol, their DNA suffered four times as damage compared with mice with a properly functioning version of the enzyme.

Patel said cells also have a second line of defense in the form of a range of DNA repair systems which, most of the time, allow them to fix and reverse different types of DNA damage.

But in some instances and in some people – particularly people from South East Asia – the repair systems fail to work, meaning their cells are unable to repair effectively.

“It’s important to remember that alcohol clearance and DNA repair systems are not perfect, and alcohol can still cause cancer in different ways – even in people whose defense mechanisms are intact,” Patel said.

By Kate Kelland

 
 
 

North Korea to Stop Nuclear Tests, Abolish Test Site Ahead of Trump Summit

North Korea to Stop Nuclear Tests, Abolish Test Site Ahead of Trump Summit
SEOUL—North Korea will suspend nuclear and missile tests effective immediately and abolish a nuclear test site in the ...
READ MORE >
 

Comey Memos Discredit Narrative That Trump Obstructed Russia Probe

Comey Memos Discredit Narrative That Trump Obstructed Russia Probe
Memos written by former FBI Director James Comey show that President Donald Trump did not interfere with the ...
READ MORE >
 

Giuliani Joins Trump’s Legal Team, Expects to End Russia Probe Within 2 Weeks

Giuliani Joins Trump’s Legal Team, Expects to End Russia Probe Within 2 Weeks
Former New York City mayor Rudy Giuliani said that he will join President Donald Trump's legal team and ...
READ MORE >
 
US

Pentagon: Man Linked to 9/11 Attacks on US Captured in Syria

Pentagon: Man Linked to 9/11 Attacks on US Captured in Syria
WASHINGTON–A man linked to the Sept. 11, 2001, attacks on the United States, who was said to have ...
READ MORE >