By Scott M. Lippman

Chemotherapies seek out cancer cells by targeting a fundamental characteristic of cancer cells: their rapid and frequent replication. But in doing so, these drugs can destroy healthy cells that also grow quickly. The result: adverse effects like hair loss and nausea.Worse, the benefits of chemotherapy are frequently short-lived. Seemingly beaten by chemotherapy, a cancer can suddenly return, spreading from its original site to other parts of the body with often catastrophic consequences. Ninety percent of cancer-related deaths are due to metastasis, and almost every cancer can be metastatic.

Why do cancers recur when therapeutic evidence suggests theyve been wiped out? The answer lies in a type of cancer cell with the powerful characteristic of normal stem cells the ability to self-renew or regenerate.

Sott M. Lippman, M.D.

Unlike normal stem cells, however, this ability in cancer stem cells does not turn off.

Cancer stem cells are a relatively new phenomenon to cancer science. Conclusive evidence of their existence was found only in 1994, though in the years since, extraordinary efforts have been made to better understand them in order to destroy them.

Its a daunting task. Cancer stem cells persist in small communities, often tucked away in the deep recesses of bone. They do not divide with dangerous abandon, which would make them easier targets of chemotherapy. In fact, they often lie dormant, essentially invisible until they begin again the process of self-renewal, differentiation and cancer relapse.

Toughest of all, they are very hard to kill, quickly developing resistance to existing drug therapies.

Nonetheless, progress is being made, some of it driven by researchers at UC San Diego Moores Cancer Center. Among them is Catriona Jamieson, M.D., Ph.D., an associate professor of medicine in the UC San Diego School of Medicine and director of Stem Cell Research at Moores Cancer Center.

Jamieson has devoted much of her career to deciphering the secrets of cancer stem cells and, more importantly, working to develop effective treatments to rid the body of them. She specializes in myeloproliferative neoplasms (MPNs) and leukemia.

See the rest here:
FRONTLINE CANCER: Working to eliminate the cancer stem cells that sustain disease