Essential metals in tissues and tumor of inbred C57BL/6 mice during the infective cycle of Lewis lung carcinoma.

The variation of tissue copper, zinc, iron, calcium, magnesium, potassium and sodium content of inbred C57BL/6 mice during the infective cycle of Lewis lung carcinoma have been studied. Tissue calcium, magnesium, potassium and sodium concentrations were well maintained during the infective cycle, probably because of their large dietary availability, copper, zinc and iron, however, showed a progressive decrease in their tissue concentrations. Liver zinc increased in parallel with the metastasising process. The important decrease in tissue iron observed agress with the characterized hypoferric response to infection. However, when the losses of metals were considered on a global organism basis, the loss of iron was not paralleled by an increase in tumor iron, but a global loss was observed. The hypoferric response did not deter tumor growth, as this was able to carry on its development with significantly decreasing neoplastic tissue iron content. The only metal actively concentrated by the tumoral mass was sodium.