5'-DFUR, A NEW ANTI-CANCER AGENT ACTIVATED SELECTIVELY IN TUMOR-CELLS .3. TISSUE DISTRIBUTION OF 5'-DEOXY-5-FLUOROURIDINE AND DERIVED 5-FLUOROURACIL IN TUMOR-BEARING MICE AND RATS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 71  (2) , 238-245
Abstract
Distribution of 5-fluorouracil (5-FU) in various tissues including transplanted tumors was examined 1, 3 (or 4), and 24 h after a single oral dose of 5''-deoxy-5-fluorouridine (5''-DFUR), Ftorafur (FT-207), or 5-FU itself to groups of mice bearing sarcoma-180 and of rats bearing Walker carcinoma-256. The levels of 5-FU derived from 5''-DFUR were highest in the tumors among the tissues examined 3 (or 4) and 24 h after administration. At the 1st h after dosing, the 5-FU level in the small intestine was close to, but that in other tissues was much lower than, the 5-FU level in the tumor of both types. Such a selective distribution of 5-FU in tumor tissues was not observed after dosing of FT-207 or 5-FU itself. Since the anticancer effect of 5''-DFUR is likely to be manifested after its conversion to 5-FU, the 5''-deoxyribose moeity of 5''-DFUR may be deemed as an efficient carrier by which the 5-FU moiety is conveyed selectively to cancer tissues.