Abstract |
The effects of ferric ammonium citrate (FAC) and desferrioxamine (DFO) on iron (Fe), and transferrin (Tf) uptake have been investigated using SK-MEL-28 human melanoma cells, which express the Tf homologue, melanotransferrin, in high concentrations. Previously we demonstrated two separate Fe uptake mechanisms from Tf, viz. a specific process mediated by the transferrin receptor (TfR) and a nonspecific process (Richardson, D. R., and Baker, E. (1990) Biochim. Biophys. Acta 1053, 1-12). Cells exposed to DFO demonstrated up-regulation of the TfR with a concurrent increase in the rate of Fe uptake. Desferrioxamine also stimulated the nonspecific process of Fe uptake, resulting in a further increase in accumulation of Fe over Tf after saturation of the specific TfR. Ferric ammonium citrate had two effects. First, it resulted in down-regulation of the TfR. Second, and paradoxically, it markedly stimulated the rate of Fe uptake from Tf by the nonspecific process without increasing the rate of nonspecific Tf uptake. These data conclusively demonstrate that two entirely different mechanisms of iron uptake from Tf exist in melanoma cells and that ferric ammonium citrate may be a useful experimental tool to further characterize the specific and nonspecific mechanisms of Fe uptake from Tf.
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Authors | D Richardson, E Baker |
Journal | The Journal of biological chemistry
(J Biol Chem)
Vol. 267
Issue 20
Pg. 13972-9
(Jul 15 1992)
ISSN: 0021-9258 [Print] United States |
PMID | 1629195
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Culture Media
- Ferric Compounds
- Quaternary Ammonium Compounds
- Transferrin
- Iron
- Deferoxamine
- ferric ammonium citrate
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Topics |
- Biological Transport
- Culture Media
- Deferoxamine
(pharmacology)
- Ferric Compounds
(pharmacology)
- Humans
- Iron
(metabolism)
- Kinetics
- Melanoma
(metabolism)
- Quaternary Ammonium Compounds
(pharmacology)
- Transferrin
(metabolism)
- Tumor Cells, Cultured
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