inositol-1-4-5-trisphosphate and Leukemia--Myelogenous--Chronic--BCR-ABL-Positive

When treated with IL-3 plus GM-CSF, K562 myeloblast cells acquired the ability to mobilize nonmitochondrial stores of intracellular Ca2+ in response to added Ins (1, 4, 5) P3. Untreated K562 cells are capable of sequestering intracellular Ca2+ but released none of this Ca2+ in response to Ins (1, 4, 5) P3. Untreated K562 cells were shown to have no detectable specific [3H] Ins (1, 4, 5) P3 binding sites and no InsP3 receptor mRNA as assayed by Northern blot and PCR. However, following IL-3 and GM-CSF treatment, both a single class of low nM KD Ins (1, 4, 5) P3 binding site and a 10 kb InsP3 receptor mRNA were detectable. The results suggest that IL-3 and GM-CSF regulate the expression of the Ins (1, 4, 5) P3 receptor gene.

Topics: Blotting, Northern; Calcium; Calcium Channels; Gene Expression Regulation, Leukemic; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Inositol 1,4,5-Trisphosphate; Inositol 1,4,5-Trisphosphate Receptors; Interleukin-3; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Polymerase Chain Reaction; Receptors, Cell Surface; Receptors, Cytoplasmic and Nuclear; RNA, Messenger; Tumor Cells, Cultured