A possible relation between dietary zinc and cAMP in the regulation of tumour cell proliferation in the rat

The possibility of an effect of zinc on the rate of tumour cell division, mediated through a regulation of cellular cAMP concentration, was investigated in the present study in rats. Dietary Zn deficiency (< 1·5 mg Zn/kg) but not Zn excess (500 mg Zn/kg) resulted in an increased cAMP concentration in transplanted hepatoma cells. Neither treatment had any effect on the cAMP concentration in regenerating liver or normal resting liver. Both the deficient and excess Zn diets resulted in a small reduction in tumour growth (not statistically significant). The results seem to indicate that the relation investigated in the present study does not apply in the cell line used