Antitumor activity of gallium and lanthanum: role of cation-cell membrane interaction.

Using the vital dye inclusion method and the radioisotopic study of Ca2+-transport, we have investigated the involvement of the gallium and lanthanum plasma-membrane interaction in the cytotoxic and antitumor characteristics of both cations. The experimental results support the hypothesis that such an interaction is the principal cause of antitumor activity, either through structural changes of the cell membrane or through inhibition of the ATPase pumps.