Studying the Interaction of an Essiac Tea and Food Mutagen

Institution: Lawrence Livermore National Laboratory
Investigator(s): Kristen Kulp, Ph.D. -
Award Cycle: 2003 (Cycle IX) Grant #: 9WB-0173 Award: $343,744
Award Type: STEP Award
Research Priorities
Etiology and Prevention>Prevention and Risk Reduction: ending the danger of breast cancer

Initial Award Abstract (2003)
The purpose of this research is to determine if Essiac® Herbal Tea, a commercially available complementary therapy widely self-administered by breast cancer patients, has an effect on the consequences of exposure to PhIP, a ubiquitous food mutagen. Essiac®Herbal Tea is a mixture of four herbal extracts that was introduced in the 1920s to treat breast cancer and is commonly used today by breast cancer patients to supplement conventional therapy. The herbs in Essiac® have long histories of use in Asian diets and medicines and have characteristics associated with altering cancer risk. However Essiac® Herbal Tea is not the subject of any scientific reports evaluating its effect on the breast. PhIP is formed naturally in meats during the cooking process. PhIP has been shown to cause DNA damage in cells, and it causes breast tumor formation in rats. In humans, the consumption of well-done meat has been linked to increased risk of breast cancer. By studying the interaction of Essiac® and PhIP, we can evaluate a commercially available dietary supplement in a model system that is relevant to a woman’s current lifestyle choices.

The central question addressed by this application is: "Does Essiac® Herbal Tea have protective properties that may have an effect on breast cancer risk by reducing breast cell damage caused by PhIP?" If cells or animals are given Essiac® Herbal Tea, in amounts similar to those recommended by the manufacturer, does this prevent cell DNA damage or tumor formation caused by PhIP?

Human breast cell lines and mammalian models (animal models with mammary glands) will be used to determine if Essiac® Herbal Tea can prevent PhIP carcinogenesis. Measuring the damage to DNA caused by PhIP exposure can be done using breast cells and techniques that are well-described in the scientific literature. We will then precisely measure whether Essiac® treatment reduces the amount of PhIP-caused DNA damage in breast cells. We will also investigate how the timing of exposure effects the amount of DNA damage; that is, if consuming Essiac® before, during or after PhIP exposure changes how much damage is caused. Mammary tumor development will be studied in rats that have been treated with PhIP to cause tumors. The animal models are well-described and their use in tumor studies is well-accepted by the scientific community. In this proposed study, we will compare the effect of Essiac® on the time it takes tumors to appear, the number of animals with tumors, the average number of tumors per animal, and how the timing of Essiac® exposure changes these outcomes.

This proposal is unique because it will rigorously test Essiac® Herbal Tea for its effect on a carcinogen that women may be exposed to in their daily diets. No peer-reviewed studies have been published that describe the effect of Essiac® on the breast or other organ systems. If we find that Essiac® alters DNA damage or tumor formation caused by PhIP, studies will need to be done to determine how Essiac® Herbal Tea works, what effects it has on the body, and if there are herbal-drug interactions. Given the wide-spread use of Essiac®, these studies are urgently needed to begin developing science-based recommendations for use of this complementary and alternative medicine among Californians.

Final Report (2006)
Women who are diagnosed with breast cancer often choose to use complementary and alternative medicines (CAMs) as treatments to supplement conventional therapies or as prevention against another cancer diagnosis. Evaluating consequences of exposure to commercially available CAM products is important because they may have unknown effects with a lasting impact on individual health. Essiac herbal extract formulations are available from several sources and used as a CAM by many breast cancer patients and survivors. Our goal in this project was to understand whether Essiac could have a protective effect on breast tumor formation by evaluating the ability of the tonic to prevent tumorigenesis caused by PhIP, a dietary carcinogen that is formed in meats that are cooked well-done.

Our project had two aims: Aim 1: To determine if Essiac® altered the induction or repair of PhIP-induced DNA adducts in human cancer cell lines. We measured single strand DNA breaks formed after PhIP exposure in human breast cancer cell lines. These single strand breaks were produced by PhIP binding to DNA, which is accepted as a potential mechanism of tumor initiation. Essiac® was administered to the cells before, during, or after PhIP exposure in order to determine if the timing of herbal tonic exposure was able to affect the induction and repair of PhIP-induced damage. The successful completion of this aim showed that Essiac did not increase or decrease PhIP-induced DNA damage, and that the timing of the administration of the herbal tonic did not affect the results.

Aim 2: To determine if PhIP induced mammary tumor development in the Sprague Dawley rat model is altered by exposure to Essiac® Herbal tonic. PhIP was used to induce mammary tumors in six-week old rats that were exposed to 3% Essiac® prior to PhIP exposure, during carcinogen exposure, or after PhIP exposure in their drinking water. Essiac treated rats were compared to control rats, which received only water. Mammary tumor incidence, multiplicity, latency, and tumor pathologies were compared among the experimental groups. The successful completion of these studies showed that, in general, Essiac had no statistically significant effect on PhIP-induced tumor formation in the rats. There was some evidence that the timing of Essiac administration (in this case, before PhIP exposure) may cause an increase in tumor formation, but the affect was not huge.

Overall, the results of this project suggest that Essiac does not protect breast cells from DNA damage or subsequent tumor formation from exposure to the breast carcinogen, PhIP. These novel results are in agreement with our other studies of this or similar herbal tonics, which have shown that Essiac may be promoting tumor formation by activating estrogen receptors. It is important to remember, however, that breast cancer cells and rodents assays are only model systems and that results from these studies cannot be directly correlated with human exposures. Important future studies for this CAM should include epidemiology studies of women that already choose to use the product and exploration of their interactions with conventional breast cancer treatments.

Essiac and Flor-Essence herbal tonics stimulate the in vitro growth of human breast cancer cells.
Periodical:Breast Cancer Research and Treatment
Index Medicus: Breast Cancer Res Treat
Authors: Kulp, K., Montgomery, J., Nelson, D.,
Yr: 2006 Vol: 98 Nbr: 3 Abs: Pg:249-59