Density-dependent regulation of epidermal growth factor receptor expression in DU 145 human prostate cancer cells.
Androgen-independent prostate cancer cells may rely on an autocrine loop for growth stimulation, and have been shown to express both the epidermal growth factor receptor (EGFR) and its stimulatory ligands. We have shown here that DU 145 prostate cancer cells have a decreased amount of EGFR in confluent cultures when compared to levels seen in subconfluent cultures. This down-regulation of EGFR numbers is not due to cell proliferation or nutrient depletion, but can be correlated only with whether cell-cell contact exists throughout the culture. This is reminiscent of the situation existing in some tumors whereby EGFR expression is higher in cells at the invading margins of the tumor.
Tillotson
J K
JK
Division of Nutrition and Endocrinology, American Health Foundation, Valhalla, New York 10595.
Rose
D P
DP
D000911:Antibodies, Monoclonal / Q000276:immunology; D001345:Autoradiography; D002452:Cell Count; D003720:Densitometry; D015536:Down-Regulation; D004591:Electrophoresis, Polyacrylamide Gel; D066246:ErbB Receptors / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D008297:Male; D011233:Precipitin Tests; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000648:ultrastructure*; D011972:Receptor, Insulin / Q000378:metabolism; D013462:Sulfur Radioisotopes; D013997:Time Factors; D016211:Transforming Growth Factor alpha / Q000276:immunology; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D013462:Sulfur Radioisotopes; D016211:Transforming Growth Factor alpha; D066246:ErbB Receptors; D011972:Receptor, Insulin