The study appears in the Wednesday, March 21 edition of PLoS ONE, the international, peer-reviewed, open-access, online publication from the Public Library of Science (PLoS).
The findings emerged from a study in which Gao and his colleagues were investigating tumor growth in mice. They discovered that some of the animals had lymphoma, and that several cell lines from those tumors carried a unique and provocative phenotype, or surface protein signature: They carried neither the Sca-1 or c-kit markers, hallmarks of normal bone marrow stem cells, nor the lineage markers most of the cancer cells had, but they did exhibit stem-like structure. The researchers suspected these unusual cells might be precancerous stems cells and designed several tests and experiments to find out more about them.
They selected three pCSC lines and injected them subcutaneously, intraperitoneally or intravenously into three groups of mice. The mice represented different levels of immune function: One group was comprised of severe combined immune deficient mice, a second group was composed of mice whose immune systems had been knocked out by radiation, but had been partially restored by an infusion of bone marrow cells; and the third group was made up of normal, healthy mice.
The results showed that the strength of the immune system affected whether or not the mice got cancer. The scientists found that the pCSCs, like normal stem cells, had the ability to create various types of benign cells in mice with healthy or recovering immune systems. These daughter cells, however, were likely to die, especially when they encountered signals to further differentiate a strong contrast to the behavior of no
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Contact: Michelle Gailiun
michelle.gailiun@osumc.edu
614-293-3737
Public Library of Science
13-Mar-2007