"A Natural Evolution: Advances and Trends in Natural Products Research"

Nick Zagorski, National Cancer Institute Benchmarks, November 17, 2004 (VOLUME 4, ISSUE 4)

"Since 1960, the Natural Products Branch (NPB), a branch of the Developmental Therapeutics Program of the National Cancer Institute (NCI), has devoted itself to finding these chemicals by setting up a repository of plant and animal samples from around the world. The NCI Natural Products Repository currently houses some 170,000 extracts from samples of over 70,000 plant and 10,000 marine organisms collected from over 25 countries, as well as over 30,000 extracts of diverse bacteria and fungi. This repository is being considered as a source of novel compounds to add to the 500,000 compounds envisaged for the NIH Roadmap Molecular Library.

"After over 40 years of screening these extracts, a critical arsenal of important cancer drugs has been developed. The fleet is led by the flagship drug Taxol®, which is used for the treatment of several cancers, notably breast and ovarian, and includes other FDA- approved drugs such as: the camptothecin analogs, topotecan and irinotecan, vinblastine and vincristine, and the microbial-derived anthracyclines such as doxorubicin and the bleomycins. Several other promising compounds also are currently being tested in clinical trials against cancer and AIDS. Overall, though, these samples haven't produced the cornucopia of efficacious anti-cancer agents that many would have hoped for.

"Gordon Cragg, D. Phil., chief of the NPB, notes that the quest for therapeutic natural products can be akin to 'looking for a needle in a haystack.' 'In the first group of extracts studied from 1960 to 1982 that gave us two anti-cancer agents, Taxol and camptothecin, over 114,000 extracts were investigated.'"