Distribution of the c-myc oncoprotein in normal and neoplastic tissues of the rat colon.
A rat model of 5-azoxymethane induced colon cancer was studied in order to correlate histopathological changes and the differential distribution of the c-myc protein. Weanling Fisher 344 rats were injected with three, one week apart, subcutaneous injections of 5-azoxymethane (AOM) (15 mg kg-1) and the animals were divided into low and high fat diet groups. Nine colon tumors, of varying degrees of malignancy, that developed in the AOM-treated rats, and sections of normal colonic mucosa were examined. A rabbit polyclonal anti-c-myc antibody produced nuclear staining at 1:100 dilution in cryostat frozen sections of the normal rat colonic mucosa and the colon tumors when prepared with a Cryostat Frozen Sectioning Aid (CFSA). The tissue localization of the c-myc antibody staining revealed: (1) in normal mucosa, nuclei of the basal portion of the mucosa; (2) in adenomatous polyps, nuclei at all levels of the mucosa; and (3) in a carcinoma in situ, intense staining of glandular epithelial cell nuclei at all levels within the tumor. This procedure may provide a sensitive method for detecting abnormal cells in the colonic epithelium that have an altered proliferative capacity.
Tulchin
N
N
Mount Sinai School of Medicine, New York, New York 10029.
Ornstein
L
L
Guillem
J
J
O'Toole
K
K
Lambert
M E
ME
Weinstein
I B
IB
D000818:Animals; D001397:Azoxymethane / Q000633:toxicity; D003106:Colon / Q000166:cytology* / Q000473:pathology*; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000473:pathology*; D007150:Immunohistochemistry; D008297:Male; D016271:Proto-Oncogene Proteins c-myc / Q000032:analysis* / Q000096:biosynthesis; D051381:Rats; D011916:Rats, Inbred F344
D016271:Proto-Oncogene Proteins c-myc; D001397:Azoxymethane