During the COVID-19 pandemic, mRNA vaccines became widely known to the general public. With their use, the immune system could recognise the virus and start creating antibodies to fight it. More precisely, mRNA (messenger ribonucleic acid) taught the immune system to recognise pathogens even before we got infected with them. On the other hand, the use of mRNA can lead to a similar response in the cancer cells.
In 2016, pediatric oncologist Elias J. Sayour and his team discovered, in the process of developing mRNA vaccines for patients with brain tumours, that mRNA could lead the immune system to destroy tumours. More surprisingly, mRNA didn’t have to be connected with a specific tumour. This was crucial and paved the way for further research, the results of which were in October 2025 published in the article ”SARS-CoV-2 mRNA vaccines sensitise tumours to immune checkpoint blockade” in Nature. The authors checked if COVID-19 mRNA-based vaccines had a similar effect on the immune system.
Research was conducted on clinical results for patients with late-stage melanoma and lung cancer, who were treated with the immunotherapy (specifically, with the immune checkpoint inhibitors). In this type of treatment, the immune system is taught to destroy the cancer, since the ability of the tumour to turn off the immune system is disabled, and the immune system can proceed with destroying the tumour. Researchers found out that the patients who received COVID-19 mRNA vaccines had, after three years higher survival rate than those who did not receive these vaccines. Even after other relevant factors that could affect this finding were taken into consideration, the connection between a higher survival rate and received COVID-19 mRNA vaccine persisted.
Since the immune system in some cases doesn’t respond to the immunotherapy (cold tumours), (COVID-19) mRNA vaccines might be a trigger for the immune system to fight the cancer in these cases as well. This will be checked in further research, and if proven, this combination – immunotherapy with immune checkpoint inhibitors and COVID-19 mRNA vaccines – might extend cancer treatment possibilities to more patients, complemented with accessibility and affordability of COVID-19 mRNA vaccines.
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