
[Cancer Research 49, 2065-2068, April 15, 1989]
© 1989 American Association for Cancer Research
Antitumor Effect of a New Multienzyme Inhibitor of Polyamine Synthetic Pathway, Methylglyoxal-bis(cyclopentylamidinohydrazone), against Human and Mouse Leukemia Cells
Hiroshige Hibasami,
Satoru Maekawa,
Taku Murata and
Kunio Nakashima
Department of Biochemistry, Mie University School of Medicine, Edobashi, Tsu, Mie 514, Japan
Methylglyoxal-bis(cyclopentylamidinohydrazone) (MGBCP) has been synthesized as a multienzyme inhibitor for the polyamine-synthesizing pathway. This drug inhibited S-adenosylmethionine decarboxylase (EC 4.1.1.50), spermine synthase and spermidine synthase activities, competitively with S-adenosylmethionine, spermidine, and putrescine, respectively. MGBCP inhibited the growth of human leukemia Molt 4B and K 562 cells at 10 to 100 µM concentrations. Spermidine and spermine levels were markedly depressed in these MGBCP-treated leukemic cells, and the synthesis of protein, but not of DNA or RNA, was significantly diminished. In in vivo experiments, MGBCP depleted spermidine and spermine in the P388 leukemic ascites cells, and prolonged the survival time of mice bearing P388 leukemia.
The S-adenosylmethionine decarboxylase-stabilizing effect of MGBCP in mouse liver, Molt 4B and K 562 cells was much less than that of the parent inhibitor methylglyoxal-bis(guanylhydrazone). Induction of ornithine decarboxylase activity by MGBCP in the cultured leukemic cells was also much less than that by methylglyoxal-bis(guanylhydrazone).
Received 6/27/88.
Revised 10/31/88. Revised 1/ 6/89.
Accepted 1/16/89.
Copyright © 1989 by the American Association for Cancer Research.