Researchers have a new tool to understand how cancers grow -- and with it a new opportunity to identify novel cancer drugs. They've been able to break apart human prostate tissue, extract the stem cells in that tissue, and alter those cells genetically so that they spur cancer.
Owen Witte, a Howard Hughes Medical Institute investigator at the University of California, Los Angeles, will present the findings on February 20, 2010, at the annual meeting of the American Association for the Advancement of Science.
Many tissues contain pools of stem cells that replenish the tissue when it's damaged or when changes take place. For instance, stem cells in the skin produce new cells to replace those irreparably damaged by the sun, and stem cells in the breast create milk-producing cells when a woman is pregnant. The hallmark of these stem cells is that they self-renew. This means that in addition to making cells with a specific function, they also make many new stem cells.
Mounting evidence suggests that these self-renewing cells are also tied to cancer. They tend to collect mutations, says Witte, and not much separates tumor cells, with their capacity for unchecked growth, from healthy, tissue-forming stem cells. "These cells have a huge capacity for self-renewal, and when the pathways that control self-renewal are augmented or changed, they can form tumors," says Witte.
Many scientists suspect that although tumors are made up of many cells, only the tumor cells derived from stem cells contribute to the growth of the tumor. For certain cancers, such as breast cancer and leukemia, that idea is well established. For others, such as prostate cancer, which Witte studies, the data are not conclusive.
Witte's group has been analyzing the relationship between tissue stem cells and cancer stem cells in the prostate. They have been attacking this problem by dividing mouse prostate tissue into its component cell types, culturing those
|Contact: Jennifer Michalowski|
Howard Hughes Medical Institute