Role of dietary magnesium and/or manganese variables on Ehrlich ascites tumor-bearing mice.

Female Swiss albino mice were placed on seven dietary regimens for five weeks. These regimens differed only in magnesium and/or manganese contents. At the end of the feeding period, the animals were inoculated with Ehrlich ascites tumor. Ten days after transplantation, Ehrlich ascites carcinoma (EAC) cells were harvested, and all animals were killed. EAC cells and plasma samples were subjected to several biochemical tests. The results suggest several conclusions. 1. Dietary supplements of magnesium and/or manganese have no effect on retarding tumor growth in vivo. 2. Dietary restriction of manganese and combined magnesium and manganese gave promising effects on retarding tumor growth in vivo. 3. Dietary magnesium deficiency, per se, had no significant effect on tumor regression in vivo. 4. In contrast to in vitro studies, manganese supplementation appeared to exert no effect on tumor progression in vivo. 5. Magnesium supplementation seemed to have no effect on tumor progression in vivo, which is in agreement with in vitro studies.