by Roberta Nichols and Alicia Di Rado

Not all breast cancers are the same. For about one of every five patients, a particularly aggressive form of the disease lies in wait.

It usually spreads early, and it often defies standard therapies. But researchers think they know the culprit behind this cancer’s fierceness — breast cancer stem cells.

George Somlo conducts collaborative studies of breast cancer stem cells. (Photo by p.cunningham)

Modern breast cancer treatments target certain proteins found on the surface of breast cancer cells. But triple-negative breast cancers have none of those proteins, so those therapies aren’t effective. Worse, they may resist other drugs, too, because they might have a higher concentration of breast cancer stem cells, which can escape chemotherapy.

“Cancer stem cells have the ability to regenerate themselves and to develop into mature tumor cells,” said George Somlo, M.D., co-director of City of Hope’s Breast Cancer Program. “They also have an uncanny ability to survive chemotherapy and radiation, allowing them to spread to other parts of the body.”

These stem cells are the target for a longstanding, productive research project between Somlo, who is director of breast oncology and high-dose therapeutics in the Department of Medical Oncology & Therapeutics Research, and researchers at the Stanford Institute for Stem Cell & Regenerative Medicine.

As part of their work, the collaborators are focusing on triple-negative breast cancers in different ethnic groups. They will study the characteristics of different types of breast cancer cells, and cancer cells in general, comparing them to normal breast tissue.

Using a new technology developed at Stanford University, the researchers will examine breast cancer stem cells among African-Americans, who seem to be more likely to have triple-negative breast cancer.

The investigators hope to identify molecular pathways that can then be targeted by more effective therapies — work that could have far-reaching implications.

“Once we characterize the breast cancer stem cell population in African-American breast cancer patients, we’ll look for any differences among ethnicities,” Somlo said. “Eventually, we hope to use the knowledge gained to develop new technology that can help us create new and more personalized treatment for patients.”