In France, lung cancer has the highest mortality rate of all cancers in men. Tobacco consumption is also the first culprit, and it is said: studies estimate that 90% of lung cancer deaths are associated with it. And even. Not all heavy smokers – those who smoke about a box a day – develop lung cancer during their lifetime.
Researchers have been asking for some time why some smokers get lung tumors and others don’t. According to a new study published in Nature Genetics and submitted to Science Alert, the reason can be found in DNA. In particular, the cells that line the lungs of some smokers seem to mutate less than others over time.
“These lung cells survive for years, even decades, and therefore can accumulate mutations with age and smoking.”explains Simon Spivack, epidemiologist and pulmonologist at Albert Einstein Medical School. “Of all the lung cell types [celles qui tapissent les poumons] is one of the most likely to become cancerous. “
While the amount of tobacco smoked is indeed associated with an increased rate of cellular mutations, “After the equivalent of about twenty-three years of smoking a box a day, this risk equals”, comments Science Alert. Of all study participants (non-smokers, occasional smokers and heavy smokers) “The heaviest tobacco users do not necessarily have the highest mutation rates”says Simon Spivack.
“Our data suggests that these people may have survived so long, despite heavy tobacco use, because they were able to suppress the accumulation of mutations.”the researchers explain. “This stabilization of mutations could stem from the fact that these people have very good systems for detoxifying cigarette smoke.”
These findings could explain why almost 80% of long-term smokers do not develop lung cancer in their lifetime. Analysis of genetic mutations could also provide some answers about the incidence of cancer in non-smokers.
While it is undeniable that tobacco is highly toxic to the body, whether these mutations turn into tumors depends on the ability to repair DNA damage. “We now want to develop new tests that can measure a person’s ability to repair or detoxify DNA, which could offer a new way to assess lung cancer risk.”concludes Jan Vijg, geneticist at Albert Einstein College of Medicine.