Immune cell discovery could help develop cancer vaccine

Scientists are on the verge of a cancer breakthrough, after working out how the body’s immune system targets cancer cells.

New research has shown a type of immune cell recognises and attacks a protein that drives cancer growth. It is led by Southampton’s Professor Salim Khakoo.

The discovery could enable better treatments to be developed for cancer patients.

Fewer side effects

Natural killer cells form part of our immune system, which protects us against disease and infections.

Previously, they were thought to attack cancer cells at random. This study now shows they specifically target cells with the XPO1 protein.

The researchers say they may be able to use this knowledge to activate more of these immune cells to destroy cancer. This would allow them to harness the immune system to kill cancer – a type of treatment known as immunotherapy.

“Our findings actually show how our body’s immune system recognises and attacks these cancer cells,” said Prof Khakoo. “Killer cells are an emerging form of immunotherapy that shows huge promise.

“They don’t attack healthy tissue in the way chemotherapy and other immunotherapies do, so are safer and have less side-effects than traditional forms of cancer treatment.”

The findings have been published in the Science Advances journal.

Better survival rates

The XPO1 protein examined by the scientists is essential for normal cell function. However, in many cancers, it becomes overactive. This allows the cancer cells to multiply unchecked.

In this study, the researchers found a peptide derived from the XPO1 protein attracted the natural killer cells. This then triggers the body’s immune response against the cancerous cells.

Prof Khakoo is a Professor of Hepatology at the University of Southampton. He is also part of the NIHR Southampton Biomedical Research Centre.

“Patients with cancer who had both active killer cells and high levels of XPO1 had significantly better survival rates,” he said. “This holds true for a range of cancers, including those with higher rates of death such as liver cancer, which has an average survival rate of only 18 months.

“As well as liver cancer, killer cell treatment in the future could be used to treat head and neck cancers, endometrial, bladder or breast cancer.”

Developing a cancer vaccine

Previous studies have linked natural killer cells to the body’s protection against cancer. However, the latest study is the first to highlight a viable technique of activating killer cells to fight the disease.

The team at Southampton are now working on the development of the world’s first vaccine that uses natural killer cells to fight cancer.

Professor Ralf Schittenhelm, from Monash University in Australia, was the study's co-author. He said the discovery could change the course of immunotherapy.

“We hope it could lead to personalised cancer treatment, especially in cases where traditional therapies have failed,” he said. “The potential to develop targeted therapies that utilise the body's own immune system is incredibly exciting."