‘Super vaccine’ could stop cancer spread, researchers say

Researchers have developed a nanoparticle-based cancer vaccine that prevented melanoma, pancreatic and triple-negative breast cancers from spreading in mice.

Scientists at the University of Massachusetts Amherst found the vaccine could both shrink and eliminate cancer tumours in rodents, as well as act preventively.

The experimental jab kept up to 88 per cent of vaccinated mice tumour-free, depending on the cancer type, with spread of the disease reduced or completely stopped in some cases.

The drug has not yet been tested in humans.

Prabhani Atukorale is assistant professor of biomedical engineering and lead author of the study.

The researcher said: “By engineering these nanoparticles to activate the immune system via multi-pathway activation that combines with cancer-specific antigens, we can prevent tumour growth with remarkable survival rate.”

Vaccines work by delivering an antigen – a small part of a pathogen, such as a cancer cell – along with an adjuvant, a compound that helps the immune system recognise and destroy the antigen.

The researchers developed a lipid nanoparticle-based approach they call a “super adjuvant”, designed to deliver two different adjuvants to overcome difficulties in cancer treatment.

Three weeks after vaccination, mice were exposed to melanoma cells.

The researchers reported that 80 per cent of vaccinated mice remained tumour-free, while none of those given traditional vaccines survived beyond 35 days.

The vaccine also appeared to prevent cancer from spreading to the lungs.

“Metastases across the board is the highest hurdle for cancer,” said Atukorale.

“The vast majority of tumour mortality is still due to metastases, and it almost trumps us working in difficult-to-reach cancers, such as melanoma and pancreatic cancer.”

In the trial, none of the mice given the experimental vaccine developed lung tumours, while all unvaccinated mice did.

In a second phase of testing, researchers used killed cancer cells taken directly from tumour masses – known as tumour lysate – rather than matching antigens to specific cancer types.

After vaccination, tumour rejection rates reached 88 per cent for pancreatic cancer, 75 per cent for breast cancer and 69 per cent for melanoma, with all mice remaining tumour-free when checked for disease spread.

“The tumour-specific T-cell responses that we are able to generate – that is really the key behind the survival benefit,” said Griffin Kane, postdoctoral research associate at UMass Amherst and co-author.

The researchers said their design “offers a platform approach that could be used across multiple cancer types”.

The findings remain early-stage animal research, and human trials will be needed to confirm whether similar results can be achieved in people.