POLYAMINES, DIAMINE OXIDASE, AND ORNITHINE DECARBOXYLASE ACTIVITY IN COLORECTAL-CANCER AND IN NORMAL SURROUNDING MUCOSA

We investigated the polyamine levels [putrescine (Put), spermidine (Sp d), and spermine (Spm)] and their metabolism by simultaneously conside ring the ornithine decarboxylase (ODC) and diamine oxidase (DAO) activ ities in human colorectal cancer and in normal surrounding tissue. Sin gle and total polyamine levels were significantly higher in the neopla stic tissue than in the surrounding mucosa from the same patients. Fur thermore, the ODC activity was significantly higher and the DAO activi ty significantly lower in the neoplastic tissue than in the surroundin g mucosa. Polyamine levels and enzymatic activities did not correlate with the clinical and histologic characteristics of patients. In norma l tissue samples, no correlation was found between single and total po lyamine levels and enzymatic activities (both DAO and ODC). On the con trary, in colorectal neoplastic samples, significant and positive corr elations were found between the levels of total polyamines, Spd, and S pm and the ODC activity. In the same specimens, DAO activity was relat ed to Spd levels and the Spd/Spm ratio, but, in those cases, the corre lation was negative. Thus, our findings suggest that, during the neopl astic growth of the colorectal mucosa, the balance between polyamine d egradation and biosynthesis is disengaged from the control exerted by the two enzymes.