Current treatments destroy cancer cells indiscriminately, draining the reservoir of cancer cells without specifically eliminating the cancer's source. "We were missing the boat because we were targeting the wrong cell," said Catriona Jamieson, MD, PhD, instructor in hematology and first author of the paper.
Other researchers have found cancer stem cells in acute myelogenous leukemia, breast cancer and two types of brain cancer. The current work, published in the Aug. 12 New England Journal of Medicine, is the first to describe these cells in chronic myelogenous leukemia. This is also the first time researchers have identified which cell becomes cancerous, transforming from a normal healthy cell to a cancer stem cell.
Jamieson and her team working with Irving Weissman, MD, the Karel H. and Avice N. Beekjuis Professor in Cancer Biology, and hematology colleagues at Stanford, the University of Toronto and UCLA, found the cells through careful detective work. She separated the cancerous cells into subgroups, each with a characteristic pattern of proteins on their cell surface. She then put each of these populations on a separate lab dish to see which could renew their population. In the end, only one group of cells had the ability to self-renew, constantly dividing to produce both new stem cells and cells that matured.
Jamieson examined these cancer stem cells and found they resembled normal cells in the blood called granulocyte/macrophage progenitor cells. This finding came as a surprise. Researchers had thought that the cancer stem cells came from normal st