Scientists have identified a mechanism by which air pollution may trigger lung cancer in non-smokers. The research showed that exposure to airborne particulate matter (PM2.5) was linked to increased risk of non-small cell lung cancer (NSCLC) with EGFR mutations.
In laboratory studies, scientists found that the same pollutant particles (PM2.5) promoted rapid changes in airway cells which had mutations in EGFR and in another gene linked to lung cancer called KRAS, driving them towards a cancer stem cell like state.
They also found that air pollution drives the influx of macrophages which release the inflammatory mediator, interleukin-1β, driving the expansion of cells with the EGFR mutations in response to exposure to PM2.5. Blockade of interleukin-1β inhibited lung cancer initiation. These findings suggest that air pollution may promote the initiation of lung cancer in cells harbouring driver gene mutations.
