Suppressive effect of soybean milk protein on experimentally induced skin tumor in mice

Abstract

We studied the effect of soybeam milk protein (SMP) in a two-stage carcinogenesis experiment on mouse skin. Mice were given soybean protein isolate (SPI) diet or SPI diet supplemented with SMP. After 4 weeks on the diets, the mice were shaved and a tumor initiator was applied. A tumor promoter was then applied twice a week on the same area of the skin throughout the experiment. After 20 weeks on the treatment, the percentage of tumor-bearing mice and the volume of tumor tended to be lower in the mice on the SMP diet than those on the SPI diet. The number of tumor was also significantly lower in the former group as compared to the latter group. There was no difference in growth between mice of the SPI and SMP groups. The results indicate the safety and the anti-carcinogenic effect of SMP in mice.