For this study, researchers reviewed existing data on gene expression patterns in various stem cell populations and ultimately came up with two different groups: one that is closer to most adult stem cells and one that's closer to embryonic stem cells.
They were also able to detect the "signature" of the embryonic stem cells in certain tumor samples and to note that these tumors tended to be more aggressive.
The findings have implications for future therapies that might be derived from stem cells. The researchers found that one oncogene, "Myc," seems to be a key regulator in converting skin cells to stem cells. But when overexpressed, this gene can induce tumors. If stem cells are created with Myc, then put back into a patient for therapy, there is also the possibility that it will stimulate cancer growth.
"As they're clearly showing, Myc is capable of reprogramming cells into stem cells, but it does that in tumors as well," Roegiers said. "It will be really important to see what Myc is doing and whether it's possible to create these types of stem cells in the lab in a way that will not threaten people when you introduce these cells."
Visit the American Cancer Society for more on different types of cancer.
SOURCES: Paul Sanberg, Ph.D., D.Sc., distinguished professor of neurosurgery and director, University of South Florida Center for Aging and Brain Repair, Tampa; Len Lichtenfeld, M.D., deputy chief medical officer, American Cancer Society, Atlanta; Fabrice Roegiers, Ph.D., co-director, Keystone Program for Epigenetics and Progenitor Cells, Fox Chase Cancer Center, Philadelphia; April 10, 2008, Cell Stem Cell
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