REVERSAL OF FOOD RESTRICTION-INDUCED INHIBITION OF MOUSE SKIN TUMOR PROMOTION BY ADRENALECTOMY

Restricting the food intake of laboratory mice and rats markedly reduces the incidence of spontaneous and experimentally induced cancers. Using the two-stage skin tumorigenesis model in CD-1 mice, we report now that food restriction suppresses 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulation of epidermal [H-3]thymidine incorporation as well as TPA promotion of skin papillomas, whereas adrenalectomy completely reverses the inhibition in [H-3]thymidine incorporation and tumor development. These results suggest that the adrenal gland may play an important role in mediating the tumor inhibitory effect of food restriction.