HerbalEGram: Volume 5, Number 3, March 2008

The results of a recent in vitro study indicate that extracts from black cohosh (Actaea racemosa, syn. Cimicifuga racemosa) may inhibit the growth of breast cancer cells. The study was published electronically by the journal Phytomedicine in November of 2007 but has not yet been published in the printed edition of the journal.¹

The authors of the study tested the effects of black cohosh fractions enriched for triterpene glycosides—the main active components of black cohosh—as well as purified components from the herb, on samples of human breast cancer cells.^2,3 They found that triterpene glycosides seemed to change the structure of the cancer cells and initiate programmed cell death, or apoptosis.

“Our manuscript provides insight into the nature of the active components in black cohosh and the precise mechanism by which black cohosh exerts its anticancer and chemopreventive activity,” said Linda Saxe Einbond, PhD, of Columbia University and lead author of the study (e-mail, February 5, 2008). She explained that the triterpene glycoside actein (isolated from the black cohosh and administered separately) was found to be particularly active at inhibiting breast cancer growth. Actein’s activity appears to be related to a receptor called HER2, which is often over-expressed in breast cancer.

“Fluorescent microscopy indicates that actein acts by inducing a stress response and apoptosis in human breast cancer cells,” said Dr. Einbond. “Understanding any new agent’s mechanism of action and active components are crucial to developing it as a treatment to prevent or fight cancer. Taken together, these results suggest that actein and related components may be useful in the prevention and therapy of breast cancer.”

The researchers have stressed that their findings are still preliminary, although the findings do suggest that black cohosh with enriched amounts of triterpene glycosides might aid in breast cancer treatment or prevention.²

According to Dr. Einbond, she and her fellow researchers are continuing their study into the anticancer potential of black cohosh. “Since most consumers of black cohosh are ingesting extracts of the herb, not pure compounds, we are devoting research to both extracts of black cohosh and the triterpene glycoside actein, an active component from the herb,” she said. She added that she and her colleagues are currently pursuing animal studies to test the efficacy of black cohosh extract on mammary cancer.

The study published in Phytomedicine was funded by the National Institutes of Health (NIH) and the Susan G. Komen Breast Cancer Foundation.³ Various concentrations of the black cohosh extract CimiPure® were used in the study, supplied by Naturex Inc. in South Hackensack, NJ.⁴

Jacques Dikansky, president and Chief Executive Officer of Naturex, stated in a recent press release: “Over one million women worldwide are diagnosed with breast cancer every year. We are proud to contribute to scientific efforts to fight this disease.”⁴

—Courtney Cavaliere

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