Source of cancer stem cells' resistance to radiation discovered at Stanford

STANFORD, Calif. — Much to the dismay of patients and physicians, cancer stem cells — tiny powerhouses that generate and maintain tumor growth in many types of cancers — are relatively resistant to the ionizing radiation often used as therapy for these conditions. Part of the reason, say researchers at Stanford University School of Medicine, is the presence of a protective pathway meant to shield normal stem cells from DNA damage. When the researchers blocked this pathway, the cells became more susceptible to radiation.

“Our ultimate goal is to come up with a therapy that knocks out the cancer stem cells,” said Robert Cho, MD, a clinical instructor of pediatrics. “If you irradiate a tumor and kill a lot of it but leave the cancer stem cells behind, the tumor has the ability to grow back.” As a result, patients can relapse months or years after seemingly successful treatment.

source: Stanford School of Medicine