There's been a heated controversy in cancer research over the past several years about the alleged presence of cancer stem cells that fuel tumour growth. But now, new research conducted by three independent teams has confirmed the existence of these "master builder" cells — a discovery that will likely lead to completely new forms of therapy for cancer patients.

Therapists are often frustrated when, after chemotherapy sessions, they see a tumor in their patient shrink, only to grow right back. This has led to the suggestion that there must be some kind of cell that drives tumor growth — and that the identification of these cells could hold important clues for future cancer treatments.

And indeed, these undifferentiated proto-cancer cells have now been discovered, the details of which were published in the journals Nature and Science. Writing in the LA Times, Rosie Mestel and Eryn Brown explain:


All three studies used molecular tricks that allowed scientists to mark certain tumor cells with bright colors. When these marked cells divided, all of the daughter cells were similarly colored. This permitted the researchers to see whether any old cell in a tumor can continue to fuel its growth or if only a subset of cells is responsible.

The three groups used different experimental approaches and different kinds of cancer, but all of them found the latter to be true.

The three research teams used different experimental approaches and different kinds of cancer, and each one of them confirmed the existence of cancer stem cells. They tested their hypothesis on mice with glioblastoma (cancer in the brain), intestinal cancer, and skin tumors.

And according to Nature's G. Driessens, this discovery is set to be a game changer:


It is too soon to know whether these results - obtained for tumours of the brain, the gut and the skin - will apply to other cancers, says Luis Parada at the University of Texas Southwestern Medical Center in Dallas, who led the brain study. But if they do, he says, "there is going to be a paradigm shift in the way that chemotherapy efficacy is evaluated and how therapeutics are developed". Instead of testing whether a therapy shrinks a tumour, for instance, researchers would assess whether it kills the right sorts of cell.

Read more about this important breakthrough at Nature and the LA Times. The studies themselves can be found here, here, and here.

Images via LA Times and Nature.