gallium nitrate

Gallium nitrate (brand name Ganite) is a drug that is used to treat hyper-calcemia, or too much calcium in the blood. Ganite exerts a hypocalcemic effect by inhibiting calcium resorption from bone, possibly by reducing increased bone turnover. It was shown, that gallium favorably altered the mineral properties to enhance hydroxyapatite crystallization and reduced mineral solubility. The drug also acted on the cellular components of bone to reduce bone resorption by decreasing acid secretion by osteoclasts. Nevertheless, ganite was withdrawn from sale, although the reasons was not the safety or effectiveness. Gallium nitrate inhibits the growth of various lymphoma cell lines in vitro and exhibits antitumor activity in patients with lymphoma. Gallium binds avidly to the iron transport protein transferrin. Transferrin-gallium complexes preferentially target cells that express transferrin receptors on their surface. Expression of transferrin receptors is particularly high on lymphoma cells. Cellular uptake of the gallium-transferrin complex leads to inhibition of cellular proliferation primarily via disruption of iron transport and homeostasis and blockade of ribonucleotide reductase. In phase II of clinical trials in patients with relapsed or refractory lymphoma, the antitumor activity of gallium nitrate is similar to, or better than, that of other commonly used chemotherapeutic agents. — NCATS