IT COULD be years before new research, which has pinpointed a way of killing breast cancer stem cells in mice, is translated into a treatment for the disease in humans, a leading Irish cancer specialist cautioned yesterday.
The warning from Prof John Crown, an oncologist at Dublin’s St Vincent’s hospital, came after scientists in the US reported finding a compound that kills breast cancer stem cells.
The researchers looked at the ability of 16,000 natural and commercial chemical compounds to kill cancer stem cells but not other cancer cells. Having narrowed them down to a small number in the laboratory they tested the compounds on mice. Salinomycin, an agricultural antibiotic given to farm animals, stood out as the most effective.
This drug was 100 times more effective at destroying the stem cells than the powerful chemotherapy agent Taxol. Injected into mice with breast cancer, salinomycin also slowed the growth of the animal’s tumours.
The US researchers believe their work has the potential to revolutionise the way cancer is tackled. Dr Piyush Gupta, from the Broad Institute in Boston and Massachusetts Institute of Technology, said: “It wasn’t clear it would be possible to find compounds that selectively kill cancer stem cells. We’ve shown it can be done.
“Our work reveals the biological effects of targeting cancer stem cells. Moreover, it suggests a general approach to finding novel anti-cancer therapies that can be applied to any solid tumour maintained by cancer stem cells.”
The scientists described their work in the journal Cell.
Asked about the research and whether this was a significant breakthrough, Prof Crown cautioned it was “a gazillion miles away from treatment of people with cancer”. He said the particular drug used on the mice was poisonous in humans.
However he said there is increasing appreciation that stem cells may be one of the reasons why it has been hard to eradicate cancers. “Stem cells may be hardier, they may be less sensitive to the effects of chemotherapy and other treatments,” he said.
“Most researchers believe that the major new breakthroughs in cancer treatment will come from specific molecular treatments,” he added.
“I think what will happen in the future with stem cells research is we will work with molecular pathways within stem cells and then look at specific drugs to target those pathways,” Prof Crown continued.