U.S. scientists have clarified how normal stem cells become cancer stem cells, as well as how cancer stem cells can cause the formation of tumors.
Dr. Xi He and associate investigator Linheng Li, both with the Stowers Institute for Medical Research, studied the intestinal system in mice in which one of the human tumor suppressor genes, PTEN, had been deleted.
“We found that a loss of PTEN in intestinal epithelial cells accompanied by a loss of PTEN in stromal cells can lead to changes that may increase the number of stem cells and change their position or location,” said Li. “These changes result in crypt fission and budding and can lead to intestinal polyposis and uncontrolled tumor growth.”
“What we learned,” added He, is that “cancer stem cells are a rare population in the tumor mass; that they are slow cycling, but more active than normal stem cells; and that cancer stem cells and stromal insertions initiate the process of primary tumorigenesis …”
The study appears on the Nature Genetics journal’s Web site.