Scientists Create Breast Tumor Stem Cells

Ince realized that he had inadvertently created tumor-initiating cells.

The study also sheds light on how cancer cells evolve, the researchers said. Conventional wisdom has it that a normal cell undergoes a number of genetic mutations to eventually become cancerous. Now it appears that some normal cells are more susceptible to becoming cancerous in the first place.

Ince's culture medium, more than two years in the making, seems to favor the cells with high susceptibility.

In particular, this study may have implications for drug testing down the road.

"Until now, most of the drug testing had been done on standard tumor cell lines that only have very few tumor stem cells in them," Ince explained. "So, even if a drug killed 99 percent of tumor cells in a Petri dish, that would not have been a guarantee that this drug actually had killed any of the tumor stem cells."

But the new cells "will be much more useful to screen for new drugs that will specifically kill tumor stem cells [because a higher percentage are stem cells]," the investigator said. "The only thing in our way to test this hypothesis is a lack of funding that is particularly severe at this time, due to recent [U.S. National Institutes of Health] budget decreases."

More information

There's more on breast cancer at the American Cancer Society.

SOURCES: Tan Ince, M.D., Ph.D., independent investigator, Brigham and Women's Hospital, and instructor, Harvard Medical School, Boston; Aug. 13, 2007,Cancer Cell