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

The study, published in the journal Cancer Cell, shows that the antibiotic tigecycline specifically targets acute myeloid leukaemia (AML) stem cells by blocking their ability to produce energy within mitochondria - the 'power station' of cells.

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.

Dr Aaron Schimmer said: "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."

He added: "Technology made this discovery possible. In three days, we found which potential leukaemia drugs might be hiding in plain sight. Sifting through every combination by hand would have taken months."

Lead author Marko Skrtic, from the University of Toronto, said: "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."

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

Oliver Childs, senior science information officer at Cancer Research UK, said: "While survival rates for leukaemia have improved, we still need better treatments for this disease, so it's encouraging to see innovative work like this, which is finding new ways to use old drugs.

"Although it's too early to say whether tigecycline will be an effective treatment for AML, this work highlights an interesting approach of blocking the energy-producing parts of cancer cells. It will be exciting to see if this lab work in cells is mirrored in the clinical trials."

Source: CRUK