Key Points

The study, led by a team from the University of Wisconsin-Madison, focused on triple-negative breast cancer and melanoma, a deadly skin cancer.

Currently, the long-term prognosis for human patients with these cancers is relatively poor.

It's because the diseases tend to recur after the initial treatments to remove the tumours.

However, using mouse models, the team could slow down the recurrence of tumours.

Quanyin Hu, a professor in the UW-Madison School of Pharmacy, said the approach could theoretically be applied to any cancer that tends to recur, such as pancreatic cancer and glioblastoma, the most common and extremely aggressive brain tumour.

The personalised vaccine approach is an extension of the team's recent discovery of pyroptotic vesicles -- tiny sacs filled with the remnants of cancer cells when they undergo programmed cell death.

Crucially, the remnants in these microscopic sacs include antigens specific to the tumour, along with other molecular bits that can help direct immune cells to find and suppress cancer cells that might remain after a tumour is surgically removed.

In the new study, published in the journal Nature Nanotechnology, the team engineered these sacs to carry an immune-stimulating drug.

They then embedded these engineered vesicles into a hydrogel that can be implanted into the space left behind after surgical removal of a tumour.

Using a melanoma mouse model and two different types of mouse models for triple negative breast cancers, including one with a human-derived tumour, the researchers compared their new approach with other cancer vaccine methods being studied.

The mice that received the hydrogel laden with their engineered sacs survived significantly longer than others.

"Compared to the other approaches, ours shows a much stronger immune response," Hu said.

Another advantage of this approach, the researchers said, is the localised nature of the treatment.

According to Hu, applying the engineered vesicles directly to the site of the removed tumour greatly reduces the risk of systemic side effects, unlike currently available treatments.

- IANS