Researchers at the University of Calgary's Hotchkiss Brain Institute have made a discovery that could lead to better treatment for patients suffering from brain cancer.

Using samples of human brain tumours, the scientists discovered that specialized immune cells called microglia are compromised in brain tumour patients. Using a drug already approved in Canada to treat fungal brain infections, they were able to re-activate the microglia and reduce brain tumour growth in test mice.

"Microglia are the brain's own dedicated immune system," said V. Wee Yong, the lead researcher. "In this study, we have formally demonstrated for the first time that these cells are compromised in living brain tumour patients."

Like other types of cancer, brain tumours start as individual stem-like cells, called brain tumour initiating cells.

These cells quickly divide and grow, eventually forming a mass, or tumour.

The main point of the discovery by Yong and his team is that tumours disable microglia, which is what allows brain tumour initiating cells to grow and develop into tumours.

Amphotericin B (AmpB) is the drug used by the researchers to re-activate the microglia. It can have harsh side effects and is used to treat severe infections of the brain and spinal cord.

"It's a rather harsh medication," said Yong. "We have demonstrated that this drug can be used in very small doses where it is not only well-tolerated but it is also effective in re-programming microglia."

Their discovery will be published Dec. 8 in the prestigious journal, Nature Neuroscience.

The team says they hope the discovery will lead to clinical trials.