|Life Extension Update Exclusive |
Vitamin E boosts lycopene’s inhibition of prostate tumor growth
A Symposium on Molecular Targets and Cancer Therapeutics sponsored by the European Organisation for Research and Treatment of Cancer, the National Cancer Institute, and the American Association for Cancer Research held in Geneva was the site of a presentation on September 30 2004 by Dr. Jacqueline Limpens of the Erasmus Medical Center in Rotterdam, Netherlands which confirmed the inhibitory effect of lycopene on prostate tumors and revealed that vitamin E may enhance that effect.
Lycopene is a carotenoid found in tomatoes and other fruits. Epidemiologic studies have established an inverse association between lycopene intake and prostate cancer risk.
The current study involved mice in who received human prostate tumor implants. The animals were divided into groups who received one of the following regimens: low dose synthetic lycopene, high dose synthetic lycopene, low dose synthetic vitamin E, high dose synthetic vitamin E, low dose synthetic lycopene plus vitamin E, or a placebo.
Dr Limpens explained the results: "We found that low dose lycopene suppressed the growth of the human prostate tumours by over half (at day 42 of the study), extending the tumour doubling time accordingly, while all other single treatments had no significant effect. However, the combination of low-dose lycopene and vitamin E produced the greatest tumour inhibition – 73%. Importantly, we also saw that the doubling time of PSA values matched the tumour responses in all the experimental groups. This means that we can use PSA values as a surrogate marker in short phase II/III human trials as it is clear that PSA values are accurately reflecting the inhibiting activity of the lycopene and vitamin E on tumour growth."
Of interest was the finding that a low dose of both nutrients provided a greater benefit than a high dose of lycopene or vitamin E alone.
Dr Limpens recommended, "Regular consumption of supplements and fortified foods may help to obtain adequate amounts of lycopene and vitamin E, which may otherwise be difficult to obtain while maintaining a balanced diet."