Anticarcinogenic Activities of Polyphenols in Foods and Herbs

The host-mediated anticancer activity, which is an anticarcinogenic activity found for polyphenols besides the inhibition of mutagenicity and tumor-promotion, is specific to some oligomeric hydrolyzable tannins. Agrimoniin, a dimer isolated from Agrimonia pilosa which is used as a herbal medicine and vegetable, was the first oligomer of this type. The macro cyclic ellagitannin dimer, such as oenothein B, often showed this activity, which was also found for some trimers and tetramers. These tannins stimulated macrophage in vitro and in vivo, resulting in inducation of interleukin-1 and increase of cytotoxic immunocytes. The anticancer activity is attributable to potential of the host-mediated defence via activation of macrophage.