ABSTRACT
The plant-screening program found that, when the folklore approach was applied for retrospective appraisal, the yield of active anticancer plants investigated could have been increased by between 50 and 100 percent. The National Cancer Institute and the Economic Botany Laboratory were always aware that they possessed limited funds, staff, and related resources. A program geared to Families of special interest was begun by the National Cancer Institute in 1972, focusing on the plant families Apocynaceae, Celastraceae, Compositae, Simaroubaceae, Rutaceae, and Thymelaeaceae, together with the families that make up the order Magnoliales. Certain zones and localities of the earth ostensibly prove better bets than others. For example, plants of tropical and subtropical climates show a higher percentage of anticancer activity, sometimes a tenfold greater proportion, than plants from temperate zones, which in turn rank higher than pl.
