Duke researchers hope new treatment can block breast cancer relapse
Posted June 8
Updated June 10
One of the great mysteries of breast cancer is how cancer sometimes returns years after a patient seems to be cured.
It emerges after hiding dormant inside bone marrow. Duke University scientists may have found a way to block cancer cells from hiding in the bones.
Doctors know that breast cancer is more treatable when all of the cancer is still within the primary tumor.
"When a breast cancer cell leaves the primary tumor and enters the blood stream, that's like being on a highway where you can go anywhere in the body," said Duke cancer researcher Dr. Dorothy Sipkins.
Sipkins says even in breast cancer's early stages, cancer cells can migrate to bone marrow where they lie dormant and can cause relapse years later.
"Once they suffer this distant relapse of the disease, it's incurable at that stage," Sipkins said.
In a study published in Science and Translational Medicine, Sipkins and colleagues looked at this process in mouse models. They found that hormone receptor positive tumor cells in vessels use a specific molecule called E-Selectin to enter the bone marrow.
Researchers found a way to block E-Selectin, so the cancer cells don't recognize the tiny bone marrow vessels.
"So, instead of docking on the vessel wall in the bone marrow and then entering the bone, instead they're stuck out in the circulation," Sipkins said.
For cancer cells already anchored within bone marrow, Sipkins' team found that the drug Plerixafor flushes them back out into the blood stream where they are more vulnerable to the immune system and cancer therapies.
Hormone receptor-positive breast cancers are the most common type, so if this concept moves forward to human trials and is found safe and effective, Sipkins says it could help prevent these relapses and prevent more deaths from breast cancer.