2023-11-03 20:00:03
No one doubts that smoking tobacco causes cancer, but until now it was not known that smoking makes the tumor more difficult to treat by undermining the body’s anti-cancer safeguards.
A study, published in ‘Science Advances‘, links smoking to harmful changes in DNA called “stop-gain mutations” that tell the body to stop making certain proteins before they are fully formed.
The scientists of Ontario Cancer Research Institute (Canada) have discovered that these stop-gain mutations are especially common in so-called ‘tumor suppressor’ genes, which produce proteins that would normally prevent the growth of abnormal cells.
“The study shows that smoking is associated with changes in DNA that disrupt the formation of tumor suppressors,” explains Nina Adler, from the University of Toronto. “Without them, abnormal cells are allowed to continue growing unchecked by cellular defenses and cancer can develop more easily.”
Adler and the team Jüri Reimand They 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 on DNA.
The findings of this study are an important piece of the puzzle behind one of the leading causes of cancer in the world.
Next, the researchers looked at whether the amount of tobacco smoked had any impact. Their analysis showed that the more people smoked, the more harmful mutations were generated, which can ultimately make the cancer more complex and harder to treat.
“Tobacco causes a lot of damage to our DNA and that can have a major impact on the function of our cells,” says Reimand. “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.”
The research also identifies other factors and processes responsible for creating a large number of stop-gain mutations, which are also called ‘nonsense’ mutations.
Some, like a group of enzymes called APOBEC which is strongly linked to stop and gain mutations in breast cancer and other types of cancer, occur naturally in the body. Other factors, such as an unhealthy diet and alcohol consumption, are also likely to have similar damaging effects on DNA, but Reimand cautions that more information is needed to fully understand how it works.
As for smoking, Adler says the findings of this study are an important piece of the puzzle behind one of the leading causes of cancer in the world.
“Everyone knows that smoking can cause cancer, but being able to explain one of the ways this works at a molecular level is an important step in understanding how our lifestyle affects our cancer risk,” adds Adler.
“This is further proof of the immense damage that smoking causes in our bodyand one more reason that quitting smoking is always the right option,” the researchers conclude.
#Smoking #blocks #proteins #attack #cancer #making #difficult #treat