ABSTRACT
Cancer is a major public health burden in both developed and developing countries. Plant-derived compounds have been an important source of several clinically useful anti-cancer agents including taxol, vinblastine, vincristine, the camptothecin derivatives, topotecan and irinotecan, and etoposide derived from epipodophyllotoxin are in clinical use all over the world. About 30 plant derived compounds have been isolated so far and are currently under clinical trials. Cancer chemopreventive agents, many of which are natural products, are capable of preventing or inhibiting the process of carcinogenesis. As with other pharmaceutical agents useful for disease prevention, a pharmacoeconomic analysis of a cancer chemopreventive formulation would need to be considered, and the composition of the formulation should improve over time. A number of promising new agents are in clinical development based on selective activity against cancer-related molecular targets, including flavopiridol, roscovitine, combretastatin A-4 phosphate , betulinic acid and silvestrol are in clinical or preclinical development.