Researchers identify potential target for brain tumour drug

In collaboration with the Press Association

Researchers believe that a drug that targets the body's immune cells could provide a new treatment for malignant brain tumours. 

Researchers at Duke's Preston Robert Tisch Brain Tumour Centre found that the drug, which has previously been used to treat melanoma and prostate cancer, re-engaged the body's cancer-damaged immune system in animal models. 

The drug works by targeting a molecule called CTLA-4 that is found on T cells - white blood cells that play an important role in the body's immune system. 

People with brain tumours often have too many regulatory T cells, which stop the immune system from fighting the tumour cells. They also have insufficient levels of cytotoxic T cells, which destroy infection and tumour cells, meaning that the tumour cells can grow and spread unchecked. 

Dr John Sampson, senior investigator at Duke, said: "We were effectively targeting 'bad' T cells that can damage the immune system if their numbers are too high, and 'good' T cells that help create an immune response to things like infections and tumours. 

"We found that this drug was able to stop the bad cells in their tracks by giving the good ones a type of bullet-proof jacket. "We hope that it will soon lead to more effective treatments for people diagnosed with these deadly brain tumours." 

Sampson and his team hope that restoring a patient's immune system in this way will mean they are better equipped to beat brain tumours. The scientists are in the process of launching a clinical trial to test the drug's effectiveness in humans. 

They also believe that the findings hold promise for the development of vaccines to boost the immune response to brain cancer. Lead investigator Dr Peter Fecci, who is a medical student at Duke, commented: "Brain tumours can be especially challenging because these patients have such high levels of regulatory T cells and also because many drugs are not able to permeate the blood-brain barrier [to get into the brain]. 

"We are encouraged by these results because this drug has a restorative effect on the immune system and doesn't need to get into the brain to be effective." 

The research was published in the journal Clinical Cancer Research