Scientists in Canada have discovered that an antibiotic normally used to treat skin and abdominal infections can also kill leukaemia cells.

The study shows that the antibiotic tigecycline specifically targets acute myeloid leukaemia stem cells by blocking their ability to produce energy within mitochondria - the "power station" of cells.

"We tested more than 500 existing drugs on leukaemia. Of the handful that made an impact, tigecycline was the most potent and revealed novel insights into the biology of leukaemia at a cellular level," study author, Marko Skrtic, said in a statement.

The researchers put together a library of more than 500 existing drugs to see if they would work as treatments for AML. A high-speed robot investigated the impact of different drug doses on AML cells.

They found that AML cells have unique energy requirements, and it's possible to selectively shut down this energy production by using tigecycline to block the production of proteins in the mitochondria.

"If you think of all the cells in the body as a power grid, we've discovered that tigecycline can cause a power outage in leukaemia stem cells, while still keeping the lights on in all the healthy cells. Technology made this discovery possible. In three days, we found which potential leukaemia drugs might be hiding in plain sight," Dr. Aaron Schimmer said.

The researchers are now beginning clinical trials with tigecycline to treat patients with AML. Schimmer says that by testing already existing drugs for their ability to combat different cancers, trials on patients can proceed at a much quicker rate as many of the side effects have already been established.

"While survival rates for leukaemia have improved, we still need better treatments for this disease. Although it's too early to say whether tigecycline will be an effective treatment for AML. It will be exciting to see if this lab work in cells is mirrored in the clinical trials," said Oliver Childs, senior science officer at Cancer Research UK.

The study was published in the journal Cancer Cell.