Treatment of Spontaneous Breast Cancers in Mice with Pearled Barley. ∗

We have presented in previous papers 1 , 2 , 3 , 4 our results with intravenous injections of yeast extract in the treatment of spontaneous breast adenocarcinomas in mice. We reported complete disappearance of these tumors in 30% of the animals, if the tumors were not of excessive size. In our last publication 4 we reported that by combining the injections of yeast extract with the feeding of polished rice we were able to double the percentage of complete regressions and to get these results not only in small tumors, but in tumors of considerable size.

We mentioned in this paper that since the preparation of beer had been changed, due to the exigencies of the war, successful results could be obtained only with a yeast extract prepared from bock beer, as bock beer was still prepared according to the old technic. Bock beer is prepared only once a year. We were planning to prepare to a large quantity of this extract when we were informed that the breweries had decided to discontinue the manufacture of bock beer for the duration of the war. Thus we were forced to abandon the use of yeast extract and to search for other sources of tumor growth-inhibiting substances.

In the preceding paper 5 we demonstrated on the growth-rate of the transplanted tumor (Sarcoma 180) an increased inhibitory effect, resulting from the combination of a polished rice diet and intravenous injections of yeast extract. From observations with other diets it was evident that this effect is not due to a deficiency in the diet. Furthermore it was possible to extract a factor from the rice which inhibited tumor growth when inject intravenously. As feeding experiments and injections of extract of pearled barley gave a test, we tested the influence of pearled barley on spontaneous tumors.