Norman R. Farnsworth, PhD, Research Professor of Pharmacognosy at the University of Illinois at Chicago, College of Pharmacy spoke on "Current Research on Herbals-How Many Needles are in the Haystack?" Dr. Farnsworth discussed the history of the search for clinically useful anti-tumor agents from natural products. This program began in 1959 at the National Service Center (precursor to NCI), by screening plants in animal systems. From 1961-1976, 20,525 plant samples were screened in one or more animal system. From 1977 to the present, NCI has screened additional plants using primarily in vitro systems. Dr. Farnsworth stated that resveratrol is the only substance found (to date) that works against initiation, proliferation and progression of cancer. Ann's NOTE: We have some articles/studies on resveratrol in our Relevant Studies section-Fruits/Vegetables area. Dr. Farnsworth commented that his group has been working on menopausal relief using herbs and is currently in Phase I/II studies using conventional methodology. He suggested that the countries most active in the search for anti-cancer agents included the United States, Japan, South Korea and China. He mentioned an international database that has over 175,000 organism represented. All are natural and not synthetic. However, there is an estimated 750,000 global plant species to be examined. It seems that these compounds are examined for their 'cytotoxic' activity and/or their antiproliferative activity. The total number of compounds that are plant derived=4,879, marine derived=2,014 and other organisms (including fungi, etc)=1,920. Of 48,581 species, 4,879 compounds were found in vitro and 1,646 in vivo, isolated from plant sources. The marine sources were examined too. From Dr. Farnsworth's report, there are many potential therapies to be explored. In fact the total number of plant derived compounds that have anticancer activity in animal models (in vivo) are: plant derived=1,646 marine derived=170 other organisms=1,418 The major chemical classes of (in vitro) cytotoxic agents from plants include: Flavinoids: 386 Quinoids: 188 Benzenoids: 240 Lignans: 209 Miscellaneous Lactones: 386 Sesquiterpenes: 524 Maytansinoids: 39 Steroids: 45 Cardenolides: 119 Isoquinoline alkaloids: 58 Indole Alkoids: 244 Diterpenes: 493 Triterpenes: 539 Total: 4,879 In vivo, has a total of 1,646 with a breakdown as follows: Lipids: 39 Carbohydrates: 98 Quinoids: 62 Benzenoids: 126 Lignans: 43 Sesquiterpenes: 133 Cardenolides: 46 Isoquinoline alkaloids: 147 Indole Alkoids: 80 Diterpenes: 151 Triterpenes: 178 Flavinoids: 85 Maytansenoids: 27 Since 1959, 4 natural products have made it to the marketplace. Since 1959, more than 50,000 plant species have been screened for anticancer activity. (0.008%). Why continue looking? Organisms produce chemical structures that would not be conceived by synthesis. Sufficient evidence that plants contain an abundance of potentially active anticancer agents. These active agents are excellent leads for structure modification to produce more active, less toxic anticancer agents. Problems: Interesting anticancer agents are usually isolated in very small amounts. Precluding further scientific study. Most chemists are reluctant to re-isolate sufficient amounts of active compounds for further study. (not explained) The most interesting plants are in the tropical rainforest, and it is extremely difficult to negotiate with these countries to acquire genetic material. Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.