Ethnobotany and ethnopharmacy--their role for anti-cancer drug development.

Local and traditional knowledge has been the starting point for many successful drug development projects over the last decades. Here we discuss some examples of anti-cancer drugs which have had enormous impact as anti-cancer agents (camptothecan, taxol and derivatives) and a few examples of drugs currently under various stages of preclinical development. Ethnobotanists investigate the relationship between humans and plants in all its complexity, and such research is generally based on a detailed observation and study of the use a society makes of plants. The requirements of modern research on natural products as, for example, outlined in the Convention on Biological Diversity (Rio Convention) and the overall approach in ethnobotanical research are also discussed. Selected phytochemical-pharmacological studies based on traditional plant use are used to highlight the potential of ethnobotany driven anti-cancer research. The link between traditionally used plants and targets of the NF-kappaB pathway is discussed using on an EU-funded, multidisciplinary project as an example. Lastly the potential of chemopreventive agents derived from traditional food plants is briefly addressed.