Novel Strategies for Plant-Derived Anticancer Agents

In this collaborative project oriented towards the discovery of novel anticancer agents from higher plants, a coordinated research effort is now well-established at the various consortial sites. Over 2,300 authenticated plant samples, mostly endemic to tropical countries, have been collected by experienced resident botanists, with the NAP-RALERT database having been used to preselect some of these through the weighting of published experimental data. To date, over 3,000 plant extracts have been prepared and evaluated in a broad range of cell-and mechanism-based bioassays that were selected because of their relevance to the proliferation of cancerous cells. Prioritization of plant extracts for activity-guided fractionation is conducted through a team approach at group meetings, and derepli-cation procedures for interfering plant polyphenols have been developed. A large number of active compounds have been obtained, many of novel structure, and the status of a selection of these (compounds 1-17) as candidates for preclinical development is described in this review.