The vaccine helps our immune system “spot and destroy” cancer cells. It targets a KRAS gene that mutates in lung, bowel and pancreatic cancers which kill around 60,000 people a year in the UK.
Dr Rachel Ambler, of The Francis Crick Institute in London, said: “If KRAS goes wrong, it enables cells in our bodies to start multiplying and turning into cancer cells.
“We have learned that, with the right help, the body’s immune system might be capable of slowing this.”
Vaccines to trigger an immune response against the commonest mutations were developed by researchers.
Dr Ambler said: “We wanted to see if we could use this knowledge to create a cancer vaccine that could not only be used to treat cancer but also give long-lasting protection.”
Dr Ambler said the vaccine slowed cancer growth in mice. If used preventatively, no cancers grew for a long time and often never.
She said: “Results suggest that the design of this vaccine has created a strong response in mice with very few side-effects.”
Teams also made a major discovery on how lung cancers evade the immune system.
Both studies were presented to experts at the 32nd EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics.