Drug compound kills breast cancer stem cells

The discovery came using a new method of screening for drugs that specifically target and kill cancer stem cells, and it could be used to find drugs targeting other cancer stem cells as well, they said.

Many teams have been looking for ways to destroy these master cancer cells in hopes of making cancer easier to cure.

"There is a lot of evidence to suggest now that these cells are responsible for many of the recurrences that are observed after treatment has stopped," Piyush Gupta of the Massachusetts Institute of Technology and the Broad Institute, whose study appears in the journal Cell, said in a telephone interview on Thursday.

The problem is that cancer stem cells are rare and difficult to study in the lab because they quickly change into other types of cells. And they are hard to kill.

"It wasn't clear it would be possible to find compounds that selectively kill cancer stem cells," Gupta said in a statement. "That's what we did."