Aminoacridine Uptake by Experimental Tumors

Previous studies with certain aminoacridine compounds revealed that a selective uptake of these compounds occurred in tumors transplanted to the lungs of rats. 1 The compounds were identified in the lung tumors by examination under ultraviolet light. As early as ten minutes after administration, the aminoacridines were more apparent in the tumors than in the surrounding lung tissue, and by 24 hours, only the tumors fluoresced under the ultraviolet light. Tumor fluorescence was weak but still present at seven days. Studies were also performed with an aminoacridine tagged with radioactive iodine ( 131 I). Radioautographs of lung tumors in animals given this compound demonstrated the selective uptake by the tumors, and counting weighed samples of tumor and normal lung in a well-scintillation counter revealed that the tumor contained five times more activity than did the normal lung. Aminoacridines are three ringed hydrocarbons (Fig 1) and include various antimalarial, antiparasitic, and antibacterial