Major findings in cancer research - 7th November 2022

Scientists have discovered how air pollution increases a person's chances of getting lung cancer. The new study has altered experts' understanding of how cancer works. It may also provide a new way of preventing it.

In the UK, 1 in 10 lung cancer cases is a result of outdoor air pollution in comparison to cigarette smoke, which is by far the biggest risk factor.

At the Crick Institute, London, a team carrying out biomedical research made the discovery that air pollution does not directly cause lung cancer. Instead, it activates cells that already have mutations which may be cancerous. The Institute's Professor Charles Swanton said the study findings made science "rethink" their knowledge of the illness.

Lung cancer is caused by mutations in lung cells which make them divide uncontrollably. However, the research highlighted that air pollution – from vehicles – doesn't directly mutate genes but awakens sleeping, bad mutations that can then lead to lung cancer.

Professor Swanton and his fellow researchers focused on one specific particle known as PM2.5, present in air pollution. Despite its tiny size – it's smaller than a speck of dust – PM2.5 causes the body to release a chemical alarm that activates cells, some of which cause harm.

The findings could result in researchers investigating what causes mutated cells to awaken, rather than looking for what originally mutates cells. Professor Swanton, aware of the potential of their findings, said, "Pollution is a lovely example, but there are going to be 200 other examples of this over the next 10 years. "

Scientists made a secondary discovery too. They stopped lung cancer from developing in mice exposed to air pollution, thanks to a drug that blocks the chemical alarm, interleukin-1-beta.

One possibility is that the same drug could, at some point, be made available to residents in areas with high pollution levels. According to Swinton, it could start a "new era" in cancer prevention.