Nucleic Acid Changes in Tumor-bearing Mice.

Abstract

The presence of spontaneous mammary tumors, transplanted sarcoma 180, and melanoma S-91 causes a considerable increase in the nucleic acid content of liver, kidney, and lung of mice of the Swiss and DBA strains. The extent of the changes seems to be related to the size and the rate of growth of tumors. The difference in the magnitude of nucleic acid changes in the 2 strains of mice, caused by the same tumor,is attributed to a strain difference. The nucleic acids, purines, and pyrimidines in melanoma S-91 were detd. at various stages of growth. The values for uracil and thymine support the assumption that the changing ratio of RNA/DNA is due to a decreased concn. of RNA in both the necrotic and the non-necrotic portions of the tumor, while the DNA decreases only in the necrotic portion.