Cancer Stem Cells Created in Lab
Wednesday, April 9, 2008; 12:00 AM
WEDNESDAY, April 9 (HealthDay News) -- Researchers at Stanford University have succeeded in transforming skin cells into what appear to be cancer stem cells, in a feat that could propel cancer research forward.
Cancer stem cells are thought to start the unhindered proliferation of cells which ultimately results in cancer.
"This has the potential for unlocking some of the secrets of cancer," said Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society, which supported the study.
"This means that now you have a good way to study cancer cells and the mechanisms involved versus getting a piece of the tumor," added Paul Sanberg, distinguished professor of neurosurgery and director of the University of South Florida Center for Aging and Brain Repair in Tampa. "Here, you have more control, more ability to look at genetic consequences and the effects of developing new therapies."
"This might allow you to identify cancers that are going to be more aggressive earlier on and allow you to tailor therapies," noted Dr. Fabrice Roegiers, co-director of the Keystone Program for Epigenetics and Progenitor Cells at Fox Chase Cancer Center in Philadelphia. "In the future, being able to identify which cancers are really being driven by the stem cell population will allow us to target those sooner."
The work, published in the April 10 issue ofCell Stem Cell, also noted that cancer stem cells are closer to embryonic stem cells (which can develop into all tissue types) than adult stem cells (which are more limited in what types of tissue they can become). This discovery could shed light on how tumors originate.
Thus far, however, researchers have been hindered in their efforts to understand this type of cell, because they are rare and difficult to grow in the lab. And, added Roegiers, there is still some controversy as to whether this type of cell actually exists in tumors.
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