32-4 |
Anti-angionenic factors in foods and their molecular mechanisms |
K. KAJI, Dept. of Food & Nutritional Sciences, Univ. of Shizuoka, Graduate School of Nutritional & Environmental Sciences, 52-1 Yada, Shizuoka, 422-8526, Japan J. Folkman first observed that a new blood vessel growth was required for a tumor to grow, by supplying the tumor with nutrients and oxygen for its exponential growth. Cancer cells have a very high rate of mutation and this has been a huge obstacle for cancer treatment because most cancer cells become drug resistant. In contrast, endothelial cells are normal diploid cells and have a much lower rate of mutation. Because of this genetic stability, anti-cancer treatment targeting tumor-induced angiogenesis is expected to be less vulnerable to such drug tolerance. It is of great interest to apply the idea of anti-angiogenic treatment to the prevention of cancer. If food factors that can inhibit angiogenesis were to be found, such factors could be used to stop small cancers from progression. We have investigated whether tea catechins have any inhibitory effects on angiogenesis and which step they affect during the process. The effects of catechins were tested on in vitro models of angiogenesis, namely, growth, migration, and tube formation of human umbilical vein endothelial cells. Catechins inhibited angiogenesis in vitro in the three different bioassays with concentrations ranging from 1.56 to 100 uM. Among catechins tested, epigallocatechin gallate (EGCG) was the most effective in inhibiting angiogenesis in all three assays. EGCG inhibited the binding of VEGF, a major angiogenesis inducing factor, to endothelial cells in a concentration dependent manner. Resveratrol and quercetin found in grapes, red wine and other food products also inhibited angiogenesis in a concentration-dependent manner (6-100 uM). These results support the idea that we can prevent cancer by taking anti-angiogenic factors in foods. We are examining the mechanisms of angiogenesis inhibition by these factors at cellular and molecular level.
Session 32, Angiogenesis and functional foods
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