RESEARCHERS AT Trinity College Dublin have developed a promising vaccine that can kill cancer cells. The method has been patented, and the researchers hope to test it in humans in two to three years.

“The idea of cancer vaccines is now a reality,” said Prof Kingston Mills, who leads the research team.

They developed a way to block the natural ability of cancer cells to suppress the immune system. Once blocked, the cancer cell can be attacked directly by specialised blood cells formed by the vaccine.

US authorities approved the first cancer vaccine only last year. It improves prostate cancer patient survival on average by 4.1 months, said Prof Mills, professor of experimental immunology and director of Trinity’s immunology research centre.

“While it works, it is not brilliant. We have demonstrated a way of making vaccines like this much more effective.”

Vaccines protect against infectious diseases by triggering the production of specialised cells that kill the infectious agent, said Prof Mills, who is a Science Foundation Ireland principal investigator.

“With cancer it is more difficult,” he said. The cancer is seen as “self” by the immune system but the tumours also release powerful immunosuppressive substances that block the immune response.

“We have found a way to immunise in this suppressive area,” Prof Mills said. “It blocks the signals that drive immunosuppression but is also able to kill the tumour cells.”

The combination treatment curbs the tumour’s immunosuppressive response while also enhancing the production of special white blood cells called killer T cells that attack and destroy the tumour cells.

The researchers have tested the method successfully against three forms of cancer in mice: skin, colon and lung. The method should also work against many more cancer types, Prof Mills said.

The research will also be published this month in the journal Cancer Research.