Nuclear size and nuclear binding of tritiated actinomycin D into epithelial cells of colon cancer patients with apparently normal colorectal mucosa.
The nuclear binding of tritiated actinomycin ([3H]AM) is clearly linked to the structural organization of the chromatin. [3H]AM decreases in cells which differentiate and becomes very low in fully differentiated cells. [3H]AM nuclear binding and nuclear size were concomitantly measured in normal-appearing flat mucosa of 10 patients bearing a colorectal cancer and compared with the colon mucosa of 10 normal individuals. In the colon of these normal subjects, there is a decreasing gradient of labeling in the upper third of the gland, with heavy labeling in the lower two-thirds and light labeling in surface epithelial cells. The ratio (R) of grain count in cells in the bottom of the glands to grain count in the surface epithelial cell varies in normal subjects from 4 to 14. There is no correlation between nuclear size and [3H]AM binding. In normal-appearing flat mucosa of cancerous patients, there is no decrease of labeling [3H]AM in the upper third of the glands; superficial cells are as labeled as those at the bottom (R = 1). There is a correlation between nuclear size and [3H]AM in these cells. Normal-appearing cells of colorectal cancer patients are probably not involved in a normal process of differentiation.
D001345:Autoradiography; D001706:Biopsy; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology*; D002843:Chromatin / Q000378:metabolism; D003106:Colon; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology*; D003609:Dactinomycin / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D006652:Histological Techniques; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology*
D002843:Chromatin; D003609:Dactinomycin