S-adenosyl-L-methionine decarboxylase activity in mouse mammary adenocarcinomas and normal mouse mammary tissue

The activity of S-adenosyl-L-methionine Decarboxylase (E. C. 4.1.1.50) was measured in two different normal and five different tumorous mouse mananary tissue samples. The soluble fraction was assayed for SAM decarboxylase activity using 14COOHlabeled SAM as the substrate. The amount of 14002 evolved was measured using a liquid scintillation counter.There was a significant elevation of SAM decarboxylase activity in the tumor sample group. The activities of the tumor tissue was x = 15.62 and SD = 8.24. The activity in the normal samples was too low to measure:These results suggest an increase in not only SAM decarboxylase activity, but also in the levels of spermidine and spermine. These increases are characteristics of cancer cells and may result in changes in enzyme activities and membrane phospholipid composition.Thesis (M.S.