New vaccine prevented up to 88% of several aggressive cancers

In an experiment with mice, a new generation vaccine was able to prevent up to 88% of aggressive cancers, through the use of dual-pathway nanoparticles that train the immune system to recognize and destroy tumor cells.

As described by , melanoma, pancreatic cancer and triple negative breast cancer (TNBC) are “serious clinical challenges”. Whether it is due to frequency or aggressiveness or the fact that they often respond poorly to treatment; It is vital that there is effective treatment for all of them.

A new study, led by researchers at the University of Massachusetts (UMass) Amherst and last week at Cell Reports Medicinebrought scientists closer to this goal, thanks to a vaccine based on immune system-stimulating nanoparticles, which effectively prevented melanoma, pancreatic cancer and TNBC in mice.

As researchers detail to New Atlas, the vaccine combines two immune system-stimulating molecules (adjuvants) in tiny lipid nanoparticles that reinforce both innate and adaptive immune responses.

The innate immune system acts as the body’s first line of defense, responding quickly and non-specifically to invaders, using cells that release inflammatory signals. The adaptive immune system takes longer to activate, but provides a targeted and long-lasting response, training T cells and B cells to recognize and remember specific threats.

Together, they form a coordinated defense: the innate system alerts and activates the adaptive system, which then provides precise and long-lasting immunity.

The mice were vaccinated subcutaneously, using a schedule prime-boost-boost on days 0, 14 and 35. The vaccines were combined with either tumor peptides (melanoma-specific antigens) or whole tumor cell lysates (a mixture of tumor proteins, to mimic real tumors).

The researchers then tested the vaccine in three aggressive cancer models: melanoma, pancreatic cancer and TNBC. They also measured the efficiency of the nanoparticles in reaching lymph nodes — where immune responses are activated — and the activation of dendritic cells, crucial immune messengers, as well as the T and B cell responses generated.

Dual-adjuvant nanoparticles produced an enhanced and effective immune response in mice. They also drained efficiently to the lymph nodes (essential for the effectiveness of the vaccine) and activated dendritic cells.

When combined with multiple peptides, 100% of vaccinated mice rejected tumorswhile all untreated or single-adjuvant groups died within a month.

Mice that survived the first tumor challenge remained tumor-free upon rechallenge months later, providing evidence of long-term immune memory.

The use of whole tumor lysate rather than defined peptides led to protection in all melanoma, pancreas and breast models. Between 69% and 88% of mice remained tumor-free after challenge, and all survived a second systemic tumor challenge..

Both T cells and B cells contributed to the immune response, suggesting that the vaccine provided broad and multifaceted immunity.

Researchers hope the vaccine will be used as both treatment and prevention, and as an approach to treat multiple types of cancer.