New evidence from three independent studies supports the idea that solid tumors in the brain, colon and skin can arise from a few bad cells known as cancer stem cells.
Cancer researchers have debated whether every cell in a tumor is capable of re-creating the tumor, or if only a few special cells have that capacity. To answer the question, researchers have transplanted tumor cells from human cancers into mice, producing mixed results.
Now, in separate attempts to settle the issue, three research groups have taken a similar approach: tagging mouse cells with fluorescent proteins to trace various cells’ fates as tumors develop within the animal’s body. In each case, tumors seem to arise from a small group of cells that act like stem cells, researchers report online August 1 in Nature and Science. Cancer stem cells are thought to be able to re-create tumors the way that normal stem cells replenish tissues.
While the studies don’t definitively demonstrate that only cancer stem cells are capable of re-creating tumors, the three papers are signposts pointing to the direction research should go, says Phil Jones, a stem cell biologist at the Hutchison/MRC Research Centre in Cambridge, England. Researchers investigating cancer stem cells need to move away from the transplant experiments and study cancer cells in their native environments, Jones says.