Curcumin (
diferuloylmethane) is a
dietary phytochemical with low toxicity that exhibits growth-suppressive activity against a variety of
cancer cells and possesses certain chemopreventive properties.
Curcumin has already been the subject of several clinical trials for use as a treatment in human
cancers. Synthetic chemical modifications of
curcumin have been studied intensively in an attempt to find a molecule with similar but enhanced properties of
curcumin. In this study, a series of novel
curcumin analogues were synthesized and screened for anticancer activity. New analogues that exhibit growth-suppressive activity 30 times that of
curcumin and other commonly used anticancer drugs were identified. Structurally, the new analogues are symmetrical 1,5-diarylpentadienone whose aromatic rings possess an
alkoxy substitution at each of the positions 3 and 5. Analysis of the effects of the analogues on the expression of
cancer-related genes usually affected by
curcumin indicated that some induced the down-regulation of
beta-catenin, Ki-ras,
cyclin D1, c-Myc, and ErbB-2 at as low as one eighth the concentration at which
curcumin normally has an effect. The analogues, however, exhibited neither harmful nor growth-suppressive effects on normal hepatocytes where
oncogene products are not activated. They also exhibited no toxicities in vivo that they may provide effective
alternative therapies for the prevention and treatment of some human
cancers.