primrose oil

Prim and Potent

Nothing is prim about the evening primrose. A component in the oil of this perennial herb and several other plants used in herbal medicine inhibits action of Her-2/neu, a cancer gene responsible for almost 30 percent of all breast cancers, reports Northwestern researchers. Patients with Her-2/neu-positive tumors have an aggressive form of the disease and a poor prognosis, according to Ruth Lupu, PhD, associate professor of medicine at the Feinberg School and director of the Evanston Northwestern Healthcare Breast Cancer Translational Research Program. Dr. Lupu’s study appeared in the November 2 issue of the Journal of the National Cancer Institute.

Evening primrose oil contains gamma-linolenic acid (GLA). Dr. Lupu and co-investigator Javier Menendez, PhD, research assistant professor of medicine, showed that treating cancer cells that overexpressed Her-2/neu with GLA not only suppressed protein levels of the oncogene but also caused a 30- to 40-fold increased response in breast cancer cells to the drug Herpetin™ (trastuzumab), a monoclonal antibody used for the treatment of many women with breast cancer.

"Treating the cancer cell lines with both GLA and Herceptin led to a synergistic increase in apoptosis [cell death] and reduced cancer growth," said Dr. Lupu. "Although further studies are necessary before GLA can enter clinical trials, these findings may reveal a previously unrecognized way of influencing the poor outcome of Her-2/neu-positive cancer patients."

GLA, one of two essential fatty acids, promotes normal functioning and growth of cells, nerves, muscles, and organs. Besides evening primrose, other sources of GLA include borage oil and black currant seed oil.