An experimental mRNA vaccine that improves existing cancer treatments could lay the foundation for a "universal" cancer vaccine, according to the team behind the breakthrough.

Scientists at the University of Florida are testing the innovation on mice and have found that it elicits a strong anti-tumor response when combined with immunotherapy. Surprisingly, the vaccine achieves this not by targeting a specific type of tumor, but by providing general support to the immune system. This means it could be used for almost any type of cancer.

"This article describes a very unexpected and exciting observation: that even a vaccine that is not specific to a particular tumor or virus—as long as it is an mRNA vaccine—can lead to a tumor-specific effect," said senior author Dr. Elias Sayour.

Cancer vaccines sound like a utopian dream, but they are not a new concept. mRNA vaccine technology, although many of us associate it with COVID-19, is changing the game when it comes to vaccine research in oncology.

Until now, there have been two main approaches to cancer vaccines. One approach involves vaccines that target specific proteins that are present in a large proportion of patients with a particular type of cancer. For example, a 2023 report detailed promising results from clinical trials of a vaccine targeting α-lactalbumin, a protein present in most triple-negative breast cancers.

Another way to approach the problem is to personalize the vaccine for a specific patient. This is where mRNA vaccines have really come into their own, offering hope for future treatments for some of the most aggressive and deadly types of cancer.

However, the new study reveals a secret option number three: developing a vaccine that can be combined with other drugs to treat cancer indiscriminately. In other words, a universal cancer vaccine.

"What we found is that by using a vaccine designed not to fight a specific form of cancer, but to stimulate a strong immune response, we can elicit a very strong anti-cancer response. So this has significant potential for widespread use in cancer patients—it may even lead us to a ready-made cancer vaccine," explained co-author Dwayne Mitchell, MD.

The experiments involved mice implanted with tumor cells to model different types of cancer: melanoma, bone cancer, and brain cancer.

The mRNA vaccine they used was similar to those formulated against COVID-19, but with one key difference: the vaccines did not have a specific target, but were simply designed to elicit a strong immune response.

When administered in combination with a drug called a PD-1 inhibitor—itself part of the new wave of cancer immunotherapies hailed as a "revolution"—the boost from the vaccine led to more positive results than would have been expected with the drug alone.

Adding the vaccine to the treatment regimen has been able to get T cells to respond to tumors that had previously resisted treatment. In some of the experiments, the mRNA formulation alone was enough to treat the cancer, and in some cases, the tumor was completely eliminated.

"This could potentially be a universal way to awaken a patient's own immune response to cancer. And that would be very important if it could be applied in human trials," Mitchell said.

"This discovery is proof of the concept that these vaccines could potentially be commercialized as universal cancer vaccines that sensitize the immune system against a patient's individual tumor," added Sayur.

Although these studies are still in the early stages, we are learning more about the potential of mRNA vaccines every day. Their promise as a tool to fight infectious and non-infectious diseases is why so many people are advocating for their use after attempts to discredit the technology.

Just recently, Sir Stephen Powis, who is stepping down from one of the highest positions in UK healthcare as director of the National Health Service in England, commented that cancer treatment is "on the cusp of a golden age." Discoveries like this will get us there.

The study was published in Nature Biomedical Engineering. | BGNES