Over last few years, there has been great interest on the anti-tumor properties of the triterpenoids, oleanolic, ursolic
and glycyrrhetinic acid in presence of many plants such as Olea europeae L., Actostaphylos uva-ursi and Glycyrrhiza
uralensis. The three acids and their derivatives show potential anti-tumor promoting and cytotoxic activities, inhibiting
proliferation, inducing apotosis and preventing invasion, which suggested that they could be developed as anti-cancer
and cancer chemopreventive agents. The mechanisms of the anti-tumor effects by triterpenoids need further investigation.
A brief review is attempted here for their anti-tumor activities and chemical modification research.