Effect of 5-Fluorouracil Administered at Low Doses on Cytotoxic Properties of Methotrexate in the in vivo Model of Mice L1210 Leukemia; According to the Schedule of Treatment

Abstract

The study compared antineoplastic effects of combined methotrexate and 5-fluorouracil therapy on LI210 lymphoid leukemia in mice according to the schedule of treatment. Methotrexate was administered at doses of: LOw.. 0.5 LOw. 5-Fluorouracil was administered at doses of: 0.2 LOIO, 0.1 LOw, 0.02 LOro. The parameters characterizing the efficacy of the therapy were survival time of mice inoculated with LI2l0 leukemic cells .. as well as 1151 excretory capacity of mice inoculated with 1251-iododeoxyuridine-Iabelled leukemic cells. It has been observed that the longest survival time of mice with LI210 leukemia is obtained when methotrexate is administered prior to 5-fluorouracil. Reversing the schedule, or simultaneous administration of the drugs results in shorter survival time. despite the administration of 5-fluorouracil at low doses, ineffective on LI210 leukemia in monotherapy. Cytotoxic effects on LI210 leukemic cells labelled with 1151UDR were present only when methotrexate was administered prior to 5-fluorouracil.

Keywords

• methotrexate
• 5-fluorouracil
• schedule of treatment
• drug synergism
• mice li210 leukemia
• experiments in vivo
• 115i-iododeoxyuridine-labelled leukemic cells