Aminopeptidases and arylamidases in normal and cancer tissues in humans.

Multiforms of aminopeptidases and arylamidases in normal human liver, stomach, lung, ileum, colon, rectum, and kidney, and cancer tissue from human liver, stomach, and lung were separated by triethylaminoethyl cellulose column chromatography. The aminopeptidases and arylamidases were solubilized from human tissues by treatment with bromelain, and their column chromatograms on triethylaminoethyl-cellulose gave different patterns of multiforms of enzymes in these tissues. The fractions of enzymes separated specificities toward L-leucyl-beta-naphthylamide, L-leucinamide, L-methioninamide, L-phenylalaninamide, and L-alaninamide. The activity of aminopeptidase toward L-leucinamide and of arylamidase toward L-leucyl-beta-naphthylamide was higher in human stomach cancer tissue and lower in hepatic cancer tissue than in normal stomach and liver, respectively. In lung cancer tissue, the activity of aminopeptidase toward L-leucinamide was abnormally low, while the activity of arylamidase toward L-leucyl-beta-napthylamide was similar to that in normal lung. The substrate specificities or patterns of the multiforms of these enzymes in cancer tissue from human liver, stomach, and lung were shown to differ from those of normal liver, stomach, and lung, respectively, by triethylaminoethyl cellulose column chromatography.