RELATIONSHIP OF ORNITHINE DECARBOXYLASE ACTIVITY AND HISTOLOGICAL-FINDINGS IN HUMAN HEPATOCELLULAR-CARCINOMA

To evaluate the correlation between the polyamine metabolism and the d egree of malignancy in hepatocellular carcinoma, we measured ornithine decarboxylase activity and polyamine concentrations in neoplastic tis sue and adjacent noncancerous tissue from resected specimens of liver from 30 patients. Ornithine decarboxylase activity, polyamines (putres cine, spermidine and spermine) and ornithine decarboxylase mRNA levels were significantly higher in hepatoma tissue than in noncancerous tis sue. The activity of this enzyme in the tumor tissue had a negative co rrelation with the histological degree of differentiation judged accor ding to a modification of the Edmondson and Steiner classification. Re sected hepatoma tissue was stained immunohistochemically with antibodi es for proliferating cell nuclear antigen (also called cyclin), a mark er of cell proliferation. We noted correlation between ornithine decar boxylase activity and the number of cells stained for this antigen (r = 0.882, p < 0.001). These results indicate that ornithine decarboxyla se activity is high in human hepatocellular carcinoma, leading to incr eased intracellular concentrations of polyamines. Ornithine decarboxyl ase activity also reflected the rate of tumor proliferation and was co rrelated with the histological findings.