Effectiveness of Anticancer Drugs Determined in Nude Mice Inoculated With [125I]5-Iodo-2′-deoxyuridine-Prelabeled Human Melanoma Cells

Anticancer drugs were tested on NIH-2 nude mice inoculated ip with BRO human melanoma celis, which are rapidly lethal for these hosts. Criteria for drug activity were a) increased host survival and b) an increased rate of radioactivity loss from mice bearing BRO cells prelabeled with [125I]5-iodo-2′-deoxyuridine. Diphtheria toxin, which is selectively toxic to human celis compared to mouse celis, prolonged host survival and accelerated 125I elimination in a dose-dependent manner. Drugs that increased the rate of 125I loss compared to the rate of untreated mice also prolonged the lives of treated mice. With one exception, drugs that did not accelerate 125I elimination had little or no effect on the length of survival.