Antitumor Activity and Toxicity of Salts of Inorganic Group IIIa Metals: Aluminum, Gallium, Indium, and Thallium

Abstract

The toxicity and antitumor activity of salts of the Group IIIa metals aluminum, gallium, indium, and thallium were determined. With the (lethal dose)(50) as a measure, the decreasing order of toxicity was TlCl(3) >/= In(NO(3))(3) > Ga(NO(3))(3) > Al(NO(3))(3). All four metals exhibited antitumor activity, but when the tumor was inoculated by a route different from that of the drug, only Ga(+3) and, to a lesser extent, In(+3) inhibited tumor growth. Ga(NO(3))(3) was found to inhibit the growth of three out of four rodent solid tumors. Gallium therefore has potential therapeutic usefulness for treatment of solid tumors in man.