Quercetin Shows Potential for Prostate Cancer Treatment
ROCHESTER, Minn.--In the March issue of Carcinogenesis (22, 3: 409-14, 2001), researchers found that the flavonoid
quercetin--found in items such as onions, apples and tea--may prevent and even treat prostate cancer. However, in a study in the same issue of the journal, researchers reported that the chemopreventive benefits of lycopene and curcumin were questionable. Headed by Nianzeng Xing at the Mayo Foundation here, a Western blot analysis showed that quercetin inhibited the prostate-specific androgen receptor, which is involved in the development and progression of prostate cancer. Quercetin also inhibited the secretion of androgen-regulated tumor markers. The study's authors concluded that the flavonoid may potentially become a chemopreventive and chemotherapeutic agent for prostate cancer.
In the same issue, researchers from Japanese universities found that concurrent administrations of lycopene (found in tomatoes) and curcumin (found in curry) did not consistently prevent prostate cancer in laboratory rats. Over a 60-week period, three 20-week experiments tested male rats with chemically-induced prostate cancer. In the first test, 15 ppm of lycopene and 500 ppm of curcumin were administered; in the second test, 5, 15 or 45 ppm of lycopene were given concurrently with 100 or 500 ppm of
curcumin; and in the third test, no botanicals were given. Researchers noted that only in the first test were lycopene and curcumin
chemopreventive. According to the authors, this data shows the inconsistency of the nutrients' benefits. To read more about either of these studies, visit
http://carcin.oupjournals.org.