PEITC in Cruciferous Vegetables Shown To Inhibit Breast Cancer: New Mechanisms and Blood Marker Discovered

James Meschino DC, MS, ROHP

Cruciferous vegetables, such as broccoli, Brussels sprouts, cabbage, and cauliflower (also bok choy, turnips) are a rich source of cancer fighting compound known as phenethylisothiocyanate (PEITC). When we eat cruciferous vegetables the chewing process activates an enzyme in these vegetable (myrosinase) that converts (hydrolyzes) their glucosinolates into various end-products such as isothiocynates.Isothiocyanates have been shown to induce phase II detoxification enzymes involved in the xenobiotic metabolism of carcinogens.A widely distributed glucosinolate found in cruciferous vegetables is gluconasartiin(phenethylglucosinolate). Myrosinase converts gluconasartiin into PEITC when we masticate cruciferous vegetables (provided they are not over cooked, in which case the enzyme myrosinase gets destroyed by the heating process).

Once formed in the gut PEITC gets absorbed into the blood stream and exerts a number of anti-cancer effects that are noteworthy. As such, researchers working with a mouse model of breast cancer showed that breast cancer development was substantially inhibited when mice, susceptible to breast cancer, were supplemented with PEITC, compared to mice not receiving PEITC.

Study Details and Findings
In a 2012 study, published in the journal of the National Cancer Institute, researchers placed mice on two diets: a control diet and a diet supplemented with PEITC for 29 weeks. The researchers performed breast tissue assessments, and measured the incidence and size of the mammary tumors. They also measured the rate of cell division (proliferation rate), the rate at which cancer cells committed suicide (apoptosis), and the rate at which tumor cells formed new blood vessels (neoangiogenesis).

The results showed that the mice given the PEITC for 29 weeks had a 56.3% reduction in breast carcinoma lesions greater than 2mm. Researchers discovered that the mice given PEITC also showed reduced cellular proliferation and neoangiogenesis, increased apoptosis, and altered expression of several proteins, including decreased ATP synthase in the tumor and increased blood levels of transthyretin.

Interestingly transthyretin is blood protein that is becoming an increasingly useful risk factor and monitoring blood marker for ovarian and lung cancer. This study indicates that increased transthyretin blood levels may be a useful screening tool to help detect early breast cancer in humans, and to monitor breast cancer survivors. No doubt this research will be followed up very aggressively in the near future, as mammograms cause radiation damage to the breast, which may contribute to breast cancer development. For this reason researchers are looking for non-invasive ways to screen for breast cancer. Blood levels of transthretin may prove to be one of those methods.

Conclusion
With respect to PEITC and breast cancer the researchers conclude,”although PEITC administration does not confer complete protection against mammary carcinogenesis, mice placed on the PEITC-supplemented diet, compared with mice placed on the control diet, clearly exhibited suppression of carcinoma progression”. Further,”PEITC inhibits the growth of mammary cancers in a mouse model with similarities to human breast cancer progression. ATP synthase and transthyretin appear to be novel biomarkers associated with PEITC exposure”.

My final comment, of course, is to eat at least one cruciferous vegetable serving per day (and don’t overcook them- raw, slightly steamed or vegetable stir fry is best).  I also take 2 capsules per day of supplement that contains to get extra indole-3 carbinol (another important anti-cancer agent from cruciferous vegetables), along with milk thistle, reishi mushroom extract and astragalus. After age 50 this combination of nutrients is desirable based on how the body’s immune and detoxification systems weaken and make us more susceptible to cancer and virulent infections.

Reference:

Shivendra V Singh, Su-Hyeong Kim, AnuradhaSehrawat, Julie A Arlotti, Eun-RyeongHahm, Kozue Sakao, Jan H Beumer, Rachel C Jankowitz, Kumar Chandra-Kuntal, Joomin Lee, Anna A Powolny, and Rajiv Dhir. Biomarkers of PhenethylIsothiocyanate-Mediated Mammary Cancer Chemoprevention in a Clinically Relevant Mouse Model. J Natl Cancer Inst, August 2, 2012