Polyamine Levels and ODC Activity in Intestinal-Type and Diffuse-Type Gastric Carcinoma

Gastric carcinomas are divided into two typesaccording to Lauren's classification: intestinal anddiffuse types. Polyamines (putrescine, spermidine, andspermine) are polycations involved in neoplastic growth of gastrointestinal mucosa. A key roleis also played by ornithine decarboxylase, the ratelimiting enzyme in polyamine metabolism. Our aim was toinvestigate whether there were differences between the two types of tumor in polyamine metabolism.Twenty-seven patients with gastric carcinoma entered thestudy. Seventeen carcinomas were classified as diffusetype and 10 as intestinal type. Polyamine levels were evaluated by high-performanceliquid chromatography. Ornithine decarboxylase activitywas measured by a radiometric technique. Polyaminelevels and ornithine decarboxylase activity weresignificantly higher in intestinal type samples than diffusetype samples. A similarity of polyamine levels inintestinal type samples with levels previously observedin patients with colorectal adenocarcinoma was also found. These findings show a differentproliferative behavior of these two types of tumor, andtherefore different therapeutic strategies can behypothesized.