Combination of tamoxifen with a compound found in the flowering plant feverfew may prevent initial or future resistance to the drug, researchers at Georgetown Lombardi Comprehensive Cancer Center have said.
The experts reported the finding online Feb. 12 in FASEB.
"A solution to tamoxifen resistance is sorely needed, and if a strategy like this can work, it would make a difference in our clinical care of breast cancer," says the study's lead investigator, Robert Clarke, PhD, DSc, a professor of oncology and physiology and biophysics at Lombardi, a part of Georgetown University Medical Center (GUMC).
larke added that the purified research chemical they tested, parthenolide, a derivative of feverfew, is being tested by other scientists as treatment for a variety of cancers, as well as other health conditions. Feverfew has long been a staple of natural medicine, and is particularly known for its effects on headaches and arthritis.
"The chemical clearly has potential, and we ought to be able to figure out fairly quickly if it can help solve tamoxifen's resistance problem," Clarke says.
Tamoxifen is a treatment of choice for breast cancer that is estrogen receptor positive, meaning that the hormone estrogen drives cancer growth. Most newly diagnosed breast cancers fall into that category. But about half of these cancers do not initially respond to tamoxifen, which is designed to block the hormone from binding to the cell's protein receptor, and many patients that do respond are at risk for developing resistance and cancer relapse.