Large bowel tumors and diamine oxidase (DAO) activity in patients: a new approach for risk group identification.
In the intestinal mucosa, diamine oxidase (DAO) seems to be involved in a feed-back regulation mechanism for the termination of proliferation. Therefore, we studied the DAO activity in large bowel tumors and in the non-affected mucosa of these patients in comparison with patients having a normal large mucosa. The DAO activity in the tumor tissue itself was diminished by 85% as compared to the surrounding mucosa. Comparing the colonic mucosa of normal and tumor bearing individuals, the DAO activity in cancer patients was diminished by 22%, while it was elevated by 64% in patients with polyps (biphasic response of the DAO activity). Histologically proven hyperproliferative mucosal alterations were indicated by a reduced DAO activity with 75% sensitivity and 42% specificity. It remains open whether this limited specificity may indicate a more sensitive reaction of the DAO activity to proliferative mucosal alterations than the histological examinations.
D006631:Amine Oxidase (Copper-Containing) / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000032:analysis*; D006801:Humans; D007413:Intestinal Mucosa / Q000201:enzymology; D007414:Intestinal Neoplasms / Q000201:enzymology*; D007417:Intestinal Polyps / Q000201:enzymology; D012307:Risk Factors
D014408:Biomarkers, Tumor; D006631:Amine Oxidase (Copper-Containing)