Antitumor effects of human recombinant interleukin-6 on acute myeloid
leukemia in mice and in cell cultures
T Givon, S Slavin, N Haran-Ghera, R Michalevicz and M Revel
Department of Bone Marrow Transplantation Center, Hadassa Medical School,
Jerusalem, Israel.
Interleukin-6 (IL-6) has been shown to inhibit growth and induce
differentiation of several myeloid leukemia cell lines. In this work, two
in vivo models of acute myeloid leukemia (AML) in mice have been used to
test the therapeutic potential of recombinant human IL-6. In mice
inoculated by a transplantable AML tumor, IL-6 injections inhibited the
development of leukemia and increased survival. The effect was related to
dose and length of treatment. In a model of radiation-induced
leukemogenesis in SJL/J mice, administration of low- dose IL-6 for 10 days,
4 months after irradiation, reduced the incidence of leukemia observed
during 1 year, whereas granulocyte- macrophage colony-stimulating factor
(GM-CSF) increased the incidence of leukemia. In vitro liquid cultures of
leukemic blood cells obtained from AML patients showed that IL-6 slowed
growth and decreased the proportion of blasts with an increase in more
mature myeloid elements in 72% of M1, M2, M4 AML cases. In contrast, GM-CSF
less often produced differentiation but stimulated leukemic cell growth in
liquid cultures, without synergism by IL-6.
Volume 79,
Issue 9,
pp. 2392-2398,
05/01/1992
Copyright © 1992 by The American Society of Hematology
