Aggressive cancers in ‘evolutionary arms race’ with the immune system

Aggressive and highly-mutated cancers are engaged in an “evolutionary arms race” with the immune system, new research suggests. Gullet and stomach cancers with faults in their systems for repairing DNA build up huge numbers of genetic mutations which make them resistant to treatments like chemotherapy. But these numerous mutations mean they appear foreign to the immune system, leaving them vulnerable to attack, and susceptible to new immunotherapies.

Scientists at the Institute of Cancer Research, London (ICR), found that these “hyper-mutant” tumours rapidly evolve strategies to disguise themselves from the immune system and evade attack. They hope that in the future, the findings could help optimise treatment with immunotherapy, and other drugs such as chemotherapy.

Dr Marco Gerlinger, team Leader in translational oncogenomics at the ICR, said: “Our new study has shown that in highly mutated tumours, cancer and the immune system are engaged in an evolutionary arms race in which they continually find new ways to outflank one another.

Watching hyper-mutated tumours and immune cells co-evolve in such detail has shown that the immune system can keep up with changes in cancer, where current cancer therapies can become resistant – and that we could use immunotherapies to shift the balance of this arms race, extending patients’ lives.

“Next, we plan to study the evolutionary link between hyper-mutant tumours and the immune system as part of a new clinical trial looking at the possible benefit of immunotherapy in bowel cancer.

The study has been published in Nature Communications.

Source: https://www.sciencefocus.com/