Medical Research Council - London Institute of Medical Sciences

Now in our 7th year of bringing you beautiful imagery from biomedical science every day

Hazardous Help
29 April 2017

Hazardous Help

It used to be fashionable. It was even promoted as medicinal. We now know smoking causes cancer. How it does this is less clear. To find out, researchers examined human lung tissue from non-smokers (pictured) and smokers. They focused on two cell types that could divide and so potentially repair damaged tissue, namely alveolar progenitors (shown in magenta) and basal stem cells. Exposing these cells to radiation caused their DNA to break, as detected using a protein marker (green). In tissue from smokers, the stem cells sprung into action, dividing and repairing the breaks. But the alveolar cells didn’t respond much. While the stem cells appear to be the heroes, the way they repaired their DNA was prone to errors, making mutations more likely. Toxic chemicals released by smoking tobacco could therefore trigger these stem cells to come to the rescue, inadvertently leading to a build-up of mutations that cause cancer.

Written by Lux Fatimathas

Search The Archive

Submit An Image

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.