STANFORD, Calif. Scientists at the Stanford University School of Medicine have identified a cancer-initiating cell in human melanomas. The finding is significant because the existence of such a cell in the aggressive skin cancer has been a source of debate. It may also explain why current immunotherapies are largely unsuccessful in preventing disease recurrence in human patients.
"These cells lack the traditional melanoma cell surface markers targeted by these treatments," said post-doctoral fellow Alexander Boiko, PhD. "Without wiping out the cells at the root of the cancer, the treatment will fail."
Boiko is the first author of the research, which will be published in the July 1 issue of Nature. He works in the laboratory of Irving Weissman, MD, the director of Stanford's Institute for Stem Cell Biology and Regenerative Medicine. Weissman is the medical school's Virginia & D.K. Ludwig Professor for Clinical Investigation in Cancer Research and the senior author of the research. He is also a member of the Stanford Cancer Center.
The cancer stem cell theory holds that, like queen bees in a hive, only a subset of cancer cells are at the root of the tumor's growth. These cells can both self-renew (that is, make more of themselves) and differentiate into other tumor cell types.
Any therapy that doesn't wipe out these elite cancer stem, or initiating, cells has no chance of completely eradicating the disease even if it destroys nearly all other tumor cells. That's why, say proponents, it can be relatively easy to get a patient into remission, but extremely difficult to prevent the cancer stem cells from roaring back and causing a relapse months or years later.
Cancer stem cells were first identified in blood cancers, but have since been identified in a number of solid tumors including bladder, brain, breast and colon cancers. Previous studies in the laboratory of assistant professor of radiation oncology Ma
|Contact: Krista Conger|
Stanford University Medical Center