Kruisbloemige groenten tegen prostaatkanker.*
Uit
een studie van menselijke prostaatkanker cellen bij muizen blijkt dat de
bioactieve stof fenylisothiocyanaat (PEITC) zeer effectief is
in het tegengaan van de groei van tumorcellen.
Na behandeling van een maand
met deze stof, in hoeveelheden die vergelijkbaar zijn wat mensen normaal eten,
bleken de tumoren bij muizen die niet behandeld waren wel twee keer zo groot te
zijn geworden. Isothiocyanaten worden vooral gevonden in kruisbloemige groenten
zoals broccoli, koolsoorten en bloemkool. Het PEITC wordt gevormd door de
groenten goed te snijden en bij het kauwen.
Een volgende stap in het onderzoek is een test bij mannen.
Vegetables
Inhibit Growth Of Prostate Cancer In Mice With Human Tumors
Chemicals
in cruciferous vegetables, such as broccoli, watercress, cabbage and cauliflower,
appear to stop human prostate
cancer
cells from growing in mice by affecting the expression of proteins, says a
University of Pittsburgh Cancer Institute study, abstract number 5601, being
presented today at the annual meeting of the American Association for Cancer
Research, at the Washington Convention Center in Washington, D.C.
"The contribution of diet and nutrition to cancer risk, prevention and
treatment have been a major focus of research in recent years because certain
nutrients in vegetables and dietary agents appear to protect the body against
diseases such as cancer," said Shivendra Singh, Ph.D., lead investigator
and professor of pharmacology and urology at the University of Pittsburgh School
of Medicine. "From epidemiologic data, we know that increased consumption
of vegetables reduces the risk for certain types of cancer, but now we are
beginning to understand the mechanisms by which certain edible vegetables like
broccoli help our bodies fight cancer and other diseases."
Dr. Singh's study is based on phytochemicals found in several cruciferous
vegetables called isothiocyanates (ITCs), which are generated when vegetables
are either cut or chewed. His laboratory has found that phenethyl-ITC, or PEITC,
is highly effective in suppressing the growth of human prostate
cancer
cells at concentrations achievable through dietary intake of cruciferous
vegetables.
In seeking to further define the mechanisms by which PEITC induces apoptosis, or
programmed cell death, mice were grafted with human prostate tumors and orally
administered a small amount of PEITC daily. After 31 days of treatment, the
average tumor volume in the control group that did not receive PEITC was 1.9
times higher than that of the treatment group. In addition, a pro-apoptotic
protein called Bax appeared to play a role in bringing about apoptosis by PEITC.
"Our next step is to design clinical trials to determine the efficacy of
PEITC for prostate
cancer
prevention in men," said Dr. Singh.
###
The study was supported by a grant from the National Cancer Institute.
Co-investigators include Stanley W. Marynowski, Jr., Dong Xiao, Ph.D., Karen L.
Lew, Yan Zeng, Rajiv Dhir, M.D., and Hui Xiao, Ph.D., all with the University of
Pittsburgh Cancer Institute.
Contact: Clare Collins
CollCX@upmc.edu
Jim Swyers
SwyersJP@upmc.edu
University
of Pittsburgh Medical Center (mei 2006)