A gene that could help explain why some non-smokers develop lung cancer has been pinpointed by US researchers. It is hoped that further research into the GPC5 gene could open the way for new targeted treatments as well as picking out those at high risk.
The Lancet Oncology reports a quarter of lung cancers globally occur in people who have never smoked. Smoking causes 90% of lung cancers, but there is still a significant number of non-smokers who develop the disease. The researchers said lung cancer in non-smokers was an increasing problem but the causes were not well understood. DNA samples from 754 people who had smoked fewer than 100 cigarettes in their lifetime were scanned to find the genetic differences that seemed most likely to affect the risk of lung cancer. When chronic respiratory disease, exposure to second-hand smoke and family history of lung cancer were taken into account, two sections of the genome seemed to be key.
In a comment piece published alongside the study, Dr Ramaswamy Govindan, from Washington University School of Medicine, said “it is far from clear” how the finding could predispose people to lung cancer. “More studies are needed to confirm these preliminary observations in the tumour samples from those with no history of tobacco smoking.” These new results could help to explain why, but much more work needs to be done to understand exactly how these gene variations are linked to lung cancer risk.