Six separate presentations at October AACR meeting focus on benefits of tomatoes, lycopene and other tomato phytonutrients
The October 2002 meeting of the American Academy for Cancer Research (AACR) featured independent presentations on cancer studies measuring the benefits of tomatoes, lycopene and/or other tomato phytonutrients.
The number of studies, and scope of research being conducted, appear to indicate an ever-increasing awareness of the beneficial potential of these tomato phytonutrients, according to Dr. Joseph Levy, a leading researcher from Ben-Gurion University, Beer-Sheva, Israel, who attended the meeting which was held in Boston.
Dr. Levy was at the October AACR meeting to present results of his own recent study, which showed that various carotenoids found in natural tomato extract may protect against the cancer-promoting effects of estrogens and phytoestrogenes. This is especially good news in the fight against breast and endometrial cancers.
In other significant research reported:
• Professor H. Nishino, formerly head of the chemo prevention division of the Japanese National Cancer Institute in Tokyo and currently at the University of Medicine in Kyoto, Japan examined liver cancer prevention in high risk liver cancer patients (hepatitis C virus carriers, those with cirrhosis and/or those having a family history) in a five-year clinical study. Results of his study showed 50 percent hepatocellular carcinoma (liver cancer) suppression in his clinical study for participants who consumed daily a combination of natural tomato extract (Lyc-O-Mato®) providing 10 mg. tomato lycopene plus other tomato phytonutrients, 10 mg. carotenes (30 percent alpha, 60 percent beta-carotene) and 50 mg. alpha tocopherols (Vitamin E). These significantly positive results suggest treating patients at high risk for liver cancer with a mixture of natural tomato extract, carotenes and vitamin E holds promise as a viable clinical application.
• The possibility that the insulin-like growth factor (IGF) axis may mediate some diet/cancer associations was supported by researchers from the University of Bristol, England. They found higher IGF levels in middle aged men who consumed more milk, dairy products, calcium, fat and polyunsaturated fat than in men who ate more fruit and vegetables and, in particular, tomatoes and tomato-rich products.
• Androgens are the classic risk factors and mitogens for prostate cancer. Researchers at Ben-Gurion University, Beer-Sheva, Israel found that lycopene and astaxanthin inhibited human prostate cancer cell proliferation induced by androgens, and decreased PSA secretion.
• Lung cancer risk is associated with higher levels of IGF-1 and lower levels of IGF binding protein-3 (IGFBP-3). A research group from Tuft University Boston evaluated the effects of lycopene supplementation on these IGF levels as well as the lung histopathological changes in ferrets exposed to cigarette smoke. The concluded that lycopene’s protective effects against lung cancer risk may be through an ability to up-regulate IGFBP-3 and interrupt the signal transduction pathway of IGF-1. Lycopene was reportedly metabolized rapidly in this smoking ferret model. The group isolated a lycopene metabolite which is probably active in the lung cancer preventive action of the carotenoid.
• Researchers from several American academic institutions are studying the relationship between dietary change and breast cancer events and all-cause mortality. They will follow participants for an average of eight years, during which different educational means will be used to help participants gradually adopt the recommended five vegetable servings per day. Results from the first 12 months of the study are showing real dietary change among participants.
AACR, a scientific society of more than 17,000 laboratory and clinical cancer researchers, was founded in 1907 to facilitate communication and dissemination of knowledge among scientists and others dedicated to the cancer problem; to foster research in cancer and related biomedical sciences; to encourage presentation and discussion of new and important observations in the field; to foster public education, science education, and training; and to advance the understanding of cancer etiology, prevention, diagnosis and treatment throughout the world.