Granulocyte-macrophage colony-stimulating factor signals for increased glucose uptake in human melanoma cells

摘要: While the primary targets for granulocyte-macrophage colony-stimulating factor (GM-CSF) are hematopoietic precursors and mature myeloid cells, GM-CSF receptors (GMR) also found on normal tissues including placenta, endothelium, oligodendrocytes as well certain malignant cells. The function of GMR in these nonhematopoietic cells is unknown. We studied human melanoma cell lines. Six seven lines tested (clones 1–5 3.44 SK-MEL-131, SK- MEL-188, SK-MEL-23, SK-MEL-22, SK-MEL-22A) expressed mRNA encoding membrane-bound soluble isoforms alpha subunit GMR. Melanoma early stages differentiation largest quantities alpha-subunit mRNA. Although five trace levels beta GMR, Scatchard analysis equilibrium binding data derived from three showed that they only low-affinity Clones SK-MEL-188 with a dissociation constant (kd) following ranges: 0.7 to 0.8, 1.2 1.8, 0.4 0.8 nmol/L, respectively. GM- CSF stimulated glucose uptake four expressing subunit, presumably through facilitative transporters, was blocked by cytochalasin B but not E. Stimulation transient, maximum stimulation occurring at approximately 30 minutes presence 1 nmol/L GM-CSF. 1.4- 2.0-fold did stimulate proliferation. These results suggest metabolic role indicate can signal increased tumor