Researchers report that, up to one in four smokers with a particular genetic defect will develop lung cancer.
“Smokers in general have nearly a 15 percent chance of developing lung cancer, far higher than in nonsmokers. Our results show that some smokers with BRCA2 mutations are at an enormous risk of lung cancer — somewhere in the region of 25 percent over their lifetime,” said study leader Richard Houlston. He’s a professor of molecular and population genetics at the Institute of Cancer Research in the United Kingdom.
“Lung cancer claims more than a million lives a year worldwide,” he said in an institute news release. “We know that the single biggest thing we can do to reduce death rates is to persuade people not to smoke, and our new findings make plain that this is even more critical in people with an underlying genetic risk.”
The link between lung cancer and the defect in the BRCA2 gene was discovered by analyzing the DNA of more than 11,000 Europeans with lung cancer and almost 16,000 without the disease.
This particular BRCA2 defect — already known to increase the risk of breast cancer — occurs in about 2 percent of people and almost doubles the risk of lung cancer, according to the study published online June 1 in the journal Nature Genetics.
The link between the BRCA2 defect and lung cancer was particularly strong among patients with the most common type of lung cancer — squamous cell lung cancer. The researchers also identified a link between squamous cell lung cancer and a defect in another gene called CHEK2, which normally prevents cells from dividing when they have damaged DNA.
The study findings suggest that drugs built to target BRCA mutations might profit patients with squamous cell lung melanoma. A class of drugs called PARP inhibitors have established promise in clinical trials concerning breast and ovarian cancer individuals with BRCA mutations, but it may not be known if these drugs could help lung cancer patients, the review authors said.
It’s also crucial to note that while the researchers found a strong link between a defect from the BRCA2 gene and lung melanoma, the study didn’t prove that this genetic defect was responsible intended for causing lung cancer.
Source: HealthDay News