POLYAMINE OXIDASE ACTIVITY AND POLYAMINE LEVELS IN HUMAN COLORECTAL-CANCER AND IN NORMAL SURROUNDING MUCOSA

Background: polyamine oxidase (PAO) is an enzyme involved in the inter conversion pathway of polyamines, compounds required for cell prolifer ation and differentiation. As the role of PAO in tumor growth is uncle ar, and no data about PAO activity in human colorectal carcinoma are a vailable, our aim was to investigate PAO activity and polyamine levels in this kind of tumor. Methods: Polyamine levels and PAO activity wer e detected in 30 neoplastic colorectal samples and surrounding mucosa by HPLC. Results: Free and N-1-acetylated polyamine levels were higher in the neoplastic tissue than surrounding mucosa of the same patient. On the contrary, PAO activity was significantly lower in the neoplast ic tissue than surrounding mucosa. Conclusion: it seems that PAO activ ity does not play an important role in the increased free polyamine le vels in human colorectal carcinoma. Instead, the low PAO activity obse rved in our study let us to hypothesize that polyamine analogues can h ave an antitumoral effect on colorectal carcinoma.