Many plants contain phytochemicals which have potential anti-cancer properties. Cruciferous vegetables such as cabbage and cauliflower contain the phytochemical
indole-3-carbinol. Studies have already suggested that indole-3-carbinol possesses anti-cancer properties. The action of indole-3-carbinol is three-old:
- Indole-3-carbinol promotes the hydroxylation of estradiol
- It increases the production of estrogen 2-hydroxyestrone which has anti-proliferation activity. Many studies suggest that 2-hydroxyestrone plays an important role in the inhibition of estrogen-induced cancers.
- Indole-3-carbinol decrease the production of the estrogen 16-alpha-hydroxyestrone, which is a carcinogenic initiator and promoter. Test have shown that 16-alpha-hydroxyestrone has activity similar to the mutagen dimethylbenzanthracene.
The purpose of this study was to investigate whether indole-3-carbinol could have inhibitory effect on the carcinogens N-methyl-N-nitrosourea and 17 beta-estradiol. The effect of indole-3-carbinol on the expression of the c-fos and c-jun mRNA (high levels are associated with cell proliferation) was also investigated.
The tests were carried out on 90 female mice, which were divided in 4 groups:
- Group 1: received the carcinogens N-methyl-N-nitrosourea and 17 beta-estradiol
- Group 2: received only 17 beta-estradiol
- Group 3: received only N-methyl-N-nitrosourea
- Group 4: received no carcinogens
After a treatment period of 30 weeks the organs of the mice where inspected.
The level of c-fos mRNA was significantly reduced in mice which received indole-3-carbinol, whreas the incidence of endometrial hyperplasia was significantly decreased by indole-3-carbinol. The researchers suggested that indole-3-carbinol has strong anti-estrogen activity. They concluded that indole-3-carbinol can act as a chemopreventive agent on estrogen mediated endometrial tumorigenesis and that the ingestion of cruciferous vegetables could help to reduce the risk of human endometrial cancer.
Source: Kenji Niwa et al. Preventive Effects of Indole-3-Carbinol on Endometrial Carcinogenesis in Mice. Japanese Journal of Reproductive Endocrinology, 2004