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Scientists have worked for decades to pinpoint the root causes of cancer. And although much research still needs to be done, a recent study indicted rogue adult bone marrow stem cells as possible seeds of the disease.

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But new research from the University of Florida finds that stem cells, the kind infused into cancer patients during bone marrow transplantation, actually can be tricked into gathering at the site of an existing tumor. Scientists studied cancerous tissue from female patients who had previously received cell transplants from healthy male donors, so they could follow where donor cells took hold by screening for the y male chromosome. The research concluded the blood stem cells that traveled to the tumor site began to look like cancer, though it's not yet clear whether they began acting like it.

Dr. Chris Cogle / UF cancer researcher

"The cautionary note to our findings is that stem cells may not be bad cells after all, and that they may just be innocent bystanders that are called into a cancerous environment."

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U-F researchers showed that stem cells actually adopted an outer cellular shell similar to that of the surrounding cancer cells, but did not appear to fully mutate into cancerous cells. An experiment in mice confirmed that this cellular mimicry happens consistently. And with that knowledge in mind, researchers say they might in the future be able to use this homing mechanism for good-possibly as a way to attack cancer on its own turf.

Dr. Chris Cogle / UF cancer researcher

"One of the ways that we could use these blood stem cells, which are tricked into coming into the cancer, is to use them as Trojan horses. To take the cells, load them with anti-cancer agents, and allow the cancer to go ahead and bring them into their environment and then, once there, those blood stem cells could liberate that agent that could kill the cancer."

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At the University of Florida Health Science Center, I'm Mike Garrison