Scientists at the Canada-based Ontario Institute of Cancer Research (OICR) found that these stop-gain mutations were especially prevalent in genes known as “tumor suppressors,” which produce proteins that would normally prevent cell growth. abnormal.
“Our study showed that smoking is associated with changes in DNA that disrupt the formation of tumor suppressors,” said Nina Adler, a doctoral student at the University of Toronto.
“Without them, abnormal cells are allowed to continue growing without control of cellular defenses and cancer can develop more easily,” he added.
The scientists used powerful computational tools to analyze DNA from more than 12,000 tumor samples from 18 different types of cancer.
Their analysis showed a strong link between stop-gain mutations in lung cancer and the telltale “fingerprint” smoking leaves in DNA.
“Our study highlights how tobacco smoking deactivates critical proteins, which are the building blocks of our cells, and the impact that can have on our long-term health,” said Reimand, an OICR researcher and associate professor at the University of Toronto. .
The study also identified other factors and processes responsible for creating a large number of stop and gain mutations, which are also called “nonsense” mutations.
Some, like the APOBEC family of enzymes, which have been linked to stop-gain mutations in breast cancer and other cancers, occur naturally in the body.
According to Reimand, other factors, such as an unhealthy diet and alcohol intake, are likely to have comparable detrimental effects on DNA, but more research is needed to fully understand how this occurs.