Two-dimensional electrophoretic patterns of proteins of normal mucosa, polyps, and carcinomas of the large intestine.

Two-dimensional protein maps of biopsies from normal mucosa, tubular adenomas (polyps), and colonic carcinomas in humans have been studied in order to obtain information on the possible precancerous role of intestinal polyps. The maps are complex and several hundred protein spots are seen after staining with Coomassie Blue. Most of the spots are common to these three tissue types, but there are also differences. Polyps and carcinomas had a strikingly similar protein pattern, different from that of normal mucosa. There were negligible differences in the two-dimensional protein maps of tubular adenomas from patients who also had colonic cancer, as compared with adenomas from persons without carcinomas. The results lend further support to the hypothesis that polyps may be precursors of carcinomas of the large intestine.