Epidermal growth factor receptors and epidermal growth factor-like activity in colorectal mucosa, adenomas and carcinomas.
The epidermal growth factor (EGF) and alpha-tumor growth factor are mitogenic proteins which bind to the EGF-receptor and may play a role in carcinogenesis or tumor progression. Our study investigated whether colorectal carcinomas and adenomas express altered levels of EGF-receptors or overproduce EGF-like activity by comparing histologically normal mucosa to carcinomas resected from the same patients. EGF-receptors were characterized by radioligand binding studies. Carcinomas contained unchanged or decreased levels of EGF-receptors in 13/16 and moderately increased levels in 3/16 patients as compared to normal mucosa. Adenomas obtained from 2 patients with familial polyposis coli and from a third patient with a coincident carcinoma had similar numbers of EGF-receptors as normal mucosa. EGF-like growth factors, in contrast, were significantly elevated in carcinoma extracts as compared to extracts from normal mucosa of the same patients. Adenomas did not contain elevated levels of EGF-like activity. We conclude that increased expression of EGF-receptors is infrequent in colonic adenocarcinomas. Increased production of EGF-like growth factors may frequently occur but seems to be associated with tumor progression rather than with premalignant lesions as represented by adenomas.
Rothbauer
E
E
Medizinische Klinik II, Ludwig Maximilians Universität, München.
Mann
K
K
Wiebecke
B
B
Borlinghaus
P
P
Lamerz
R
R
Pratschke
E
E
Krämling
H J
HJ
Pfeiffer
A
A
D011125:Adenomatous Polyposis Coli / Q000473:pathology; D000328:Adult; D000368:Aged; D002455:Cell Division; D003106:Colon / Q000473:pathology; D003111:Colonic Polyps / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000473:pathology*; D004815:Epidermal Growth Factor / Q000032:analysis*; D066246:ErbB Receptors / Q000032:analysis*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011230:Precancerous Conditions / Q000473:pathology; D012007:Rectum / Q000473:pathology
D004815:Epidermal Growth Factor; D066246:ErbB Receptors