A promising target for next-generation cancer therapies might not be a target after all, according to a new study in Nature [subscription required]. The work calls into question the "cancer stem cell theory," which claims that a rare class of cells, cancer stem cells, are responsible for initiating and spreading cancer tumors. But by tweaking previous experimental procedures, researchers working with human melanoma cells in mice now report that cancer stem cells are much more prevalent that previously thought.
"We're not trying to claim there is no merit to the field, but we think that the frequency of cancer stem cells will be much higher," said [co-author] Sean Morrison... . "And there will be some cancers like melanoma where lots of cells will be tumorigenic and it won't be possible to treat those cancers by treating a small subset of cells" [Wired Science].
Cancer stem cells—so-called because they share genetic ...
