Effects of recombinant human granulocyte colony stimulating factor (rG-CSF) on murine myeloid leukemia: stimulation of proliferation of leukemic cells in vitro and inhibition of development of leukemia in vivo
Tamura, M.; Hattori, K.; Ono, M.; Hata, S.; Hayata, I.; Asano, S.; Bessho, M.; Hirashima, K.
Leukemia 3(12): 853-858
1989
ISSN/ISBN: 0887-6924 PMID: 2479801 Document Number: 328324
We have established an experimental murine myeloid leukemia model and investigated the effects of recombinant granulocyte colony stimulating factor (rG-CSF) on myeloid leukemia in vitro and in vivo. rG-CSF stimulated colony formation by the leukemic cells in semisolid agar medium, and exponential growth of the clonogenic cells in suspension medium. Thus, rG-CSF was able to stimulate both the differentiation and self-renewal processes of the leukemic stem cells in vitro. However, 14 consecutive daily injections of rG-CSF prolonged the mean survival time of the mice implanted with the leukemic cells. This effect of rG-CSF was accompanied by a delay in the emergence of the blast cells in peripheral blood and by a decreased byast population in the spleen, suggesting that development of leukemia was suppressed in the rG-CSF-treated-mice. The prolongation of the survival time by rG-CSF was more evident when rG-CSF was administered in therapeutic combination with cyclophosphamide. These results indicate that the effect of rG-CSF on the development of leukemia is not exactly predicted from in vitro experiments.