Given that researchers are making strong progress in both understanding the biochemistry of stem cells and in targeted cell-killing therapies, I don't expect the cancer stem cell hypothesis to remain a hypothesis for more than another few years. "After years of working toward this goal, scientists [have] found a way to isolate cancer stem cells in tumors so they can target the cells and kill them, keeping cancer from returning. A research team led [discovered] that a particular protein only appears in stem cells. Until now, researchers knew of proteins that appeared in both regular cancer cells and stem cells, but none that just identified a stem cell. The group has already begun work to use the protein as a target for a new compound that once developed would kill the stem cells and kill the cancer. By targeting the stem cells, scientists and physicians also would be able to stop the cancer from returning. ... Researchers expect to have initial testing completed to begin the first phase of clinical trials within 5 years ... The compound, if successful in human trials, is expected to be available to the public within 10 years."

Link: http://www.ouhsc.edu/article-display.asp?idnum=1302