Nucleolar organizer regions (NORs) in the cells of normal mucosa and tumors of human colon.

The purpose of the present study was to analyse the differences in the number Ag-NORs dots in the selected cases of carcinomas and adenomas of the large intestine as well as in the stromal cells, surface epithelium and epithelium of crypts of the large intestine. Ag-NORs dots are consider to be argyrophilic proteins associated with so called nucleolar organizer regions (NORs). The increase in their number is regarded as a marker of metabolic and proliferative changes in the cells. In our material we found a definite statistical differences in the number of Ag-NORs dots in carcinomas, adenomas and normal mucosa of the colon. The problem of adenomas grade IV with visible signs of malignancy, atypical number of Ag-NORs is, however, controversial. This may be an indicator of the different growth dynamics of these adenomas.