Experimental cancer vaccine clears four in 10 pancreatic tumors and prevents disease from returning, study on mice shows

An experimental cancer vaccine has been proven to treat four out of 10 pancreatic tumors – a glimmer of hope for patients with the aggressive disease.

In a study in mice, the vaccine “cured” 43 percent of pancreatic tumors and prevented the cancers from coming back if they relapsed.

The vaccine uses a weakened food poisoning pathogen to stimulate an immune response and contains a piece of the recipient’s tumor to train their body to fight its own cancer.

While the study is still preliminary and conducted on mice, the University of Massachusetts team hopes to begin human trials in the coming years.

If approved, it could be a lifeline for patients diagnosed with pancreatic cancer – a situation that is currently tantamount to a death sentence in the US. Only 8.5 percent of Americans survive longer than five years.

Compared to other types of cancer, pancreatic cancer is quite rare. It is the third leading cause of cancer death in the United States, claiming 50,550 lives each year.

It is difficult to detect early because the pancreas is located deep in the body and doctors cannot see or feel the tumor during routine physical exams.

Once discovered, treatment is difficult because tumors are often surrounded by important tissue, making it difficult for treatment to reach the cancer directly without damaging the tissue.

Initially, the research team will use the vaccine to treat liver cancer, followed by pancreatic cancer.

Liver cancer is one of the leading causes of death worldwide, causing more than 700,000 deaths each year.

The new vaccine consists of a molecule taken from inside a cancer cell and wrapped in a protein from a chicken egg called ovalbumin.

Vaccines for yellow fever, influenza, MMR and rabies contain small amounts of egg protein because they are grown in chicken eggs.

The molecule and protein are delivered into a genetically modified salmonella bacteria that is non-toxic and releases the vaccine.

When injected into the blood, the weakened salmonella bacteria trigger an immune reaction.

A type of white blood cell called T cells is also triggered by the protein that trains the immune system to attack future cancer cells.

The team tested the treatment on mice with pancreatic cancer.

Neil Forbes, professor of chemical engineering and senior author of the study, said: “We had complete healing in three out of seven pancreas mouse models.” We’re really excited about that; it dramatically increased survival.”

The researchers then attempted to re-introduce pancreatic tumors into the vaccinated mice.

“None of the tumors grew, meaning the mice had developed immunity, not just to ovalbumin, but also to the cancer itself,” Professor Forbes said.

“The immune system has learned that the tumor is immunogenic.” “I’m continuing to work on finding out how this actually happens,” he added.

The team plans to seek FDA approval to initiate clinical trials within a few years.

Before the trials can begin, they must repeat the experiments on other animals and ensure that the Salmonella strain is safe to use in humans.

Professor Forbes, whose grandfather died of prostate cancer, said: “This is not just an academic exercise.” “I’m really trying to do cancer therapy.”

The study was published last week in the journal Frontiers in immunology.

In previous research, the team showed that injecting the modified Salmonella into the blood was effective in treating liver tumors in mice.

Professor Forbes said the new immunotherapy had “the potential to be effective across a wide range of cancer patients”.