It is widely hoped that neural stem cells will eventually be useful for replacing nerves damaged by degenerative diseases like Alzheimer disease and multiple sclerosis. But there may also be another use for such stem cells--delivering anti-cancer drugs to cancer cells.
A Perspective article in PLoS Medic ine, by Professor Riccardo Fodde (Erasmus Medical Center, The Netherlands), discusses a new study in mice, published in the launch issue of PLoS ONE (www.plosone.org), that showed that neural stem cells could be used to help deliver anti-cancer drugs to metastatic cancer cells.
One of the characteristics of neural stem cells is their tendency to move towards diseased areas (scientists call this phenomenon "pathotropism"). This characteristic, says Professor Fodde, "makes them particularly attractive candidates not only to replace damaged tissue in degenerative pathologies, but also to deliver therapeutic molecules in patients with disseminated metastatic cancer."
In the study published in PLoS ONE, Karen Aboody and colleagues report on the eradication of disseminated metastases in a mouse model of a cancer called neuroblastoma. The researchers took advantage of the tumor-tropic (selective migration towards cance r cells) properties of neural stem cells engineered to express an enzyme that activates an anti-cancer drug.
It is much too early to know whether this study in mice will lead to any kind of valuable treatment for humans with cancer. Clinical trials in humans are needed before doctors can know whether stem cells have a role in cancer therapy. Professor Fodde also says that there will be a number of concerns about the safety of such human trials, which he discusses in his Perspective.