Modulation of transferrin receptor expression by insulin and granulocyte-macrophage colony stimulating factor in AML-193 leukemic cells.
The effects of insulin and granulocyte-macrophage colony stimulating factor (GM-CSF) on the expression of transferrin receptors in AML-193 myeloid leukemia cell line were investigated. Insulin, alone or in combination with GM-CSF, caused an increase in surface transferrin receptors within 5 min. This increase was inhibited by hyperosmolarity but not by cycloheximide suggesting the involvement of receptor recycling from internal pools. In contrast, receptor increase after 18 h of incubation with insulin and GM-CSF was sensitive to cycloheximide indicating that long term effects of these growth factors are mediated through protein synthesis. These results may have implications on combined GM-CSF + antitransferrin receptor antibody therapy of leukemias.
Akin
C
C
Department of Microbiology and Immunology, University of Louisville, KY 40292.
Sonnenfeld
G
G
D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D007951:Leukemia, Myeloid / Q000378:metabolism*; D011990:Receptors, Transferrin / Q000187:drug effects / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D007328:Insulin; D011990:Receptors, Transferrin; D016178:Granulocyte-Macrophage Colony-Stimulating Factor