Are tumours fuelled by stem cells?

HOW can a cancer come back after it's apparently been eradicated? Three new studies are bolstering a long-debated idea: that tumours contain their own pool of stem cells that can multiply and keep fueling the cancer, seeding regrowth.

If that's true, scientists will need to find a way to kill those cells, apart from how they attack the rest of the tumour.

Stem cells in healthy tissues are known for their ability to produce any kind of cell. The new research deals with a different kind, cancer stem cells. Some researchers, but not all, believe they lurk as a persisting feature in tumours.

Over the past decade, studies have found evidence for them in tumours like breast and colon cancers. But this research has largely depended on transplanting human cancer cells into mice that don't have immune systems, an artificial environment that raises questions about the relevance of the results.


Now, three studies reported online in the journals Nature and Science present evidence for cancer stem cells within the original tumours. Again, the research relies on mice. That and other factors mean the new findings still won't convince everyone that cancer stem cells are key to finding more powerful treatments.

But researcher Luis Parada, of the University of Texas Southwestern Medical Centre in Dallas, believes his team is onto something. He says that for the type of brain tumour his team studied, "we've identified the true enemy."