The Globe and Mail discusses cancer stem cells and what they mean for future research: "It is not unreasonable to say that all this time, the 30 or 40 years that chemotherapy and radiation [have] been around, we've been going after the wrong cells. All of our therapies have been targeting and killing the pawns. But like chess, you have to kill the king to win the game. ... Abnormal stem cells have now been identified as the engines driving certain cancers of the blood, breast, brain, bone and prostate. And today, two research groups [report] that they have pinpointed aberrant stem cells as the source of colon cancer, the second leading cause of cancer deaths. ... The exciting thing is that the cancer stem cell model explains so much about how cancers develop. What it also explains is why we're not doing better at treating cancer." Cancer stem cells are identifiably different, which means they can be targeted by the latest generation of therapies under development.