Membrane glycoprotein changes in primary mammary tumors associated with autonomous growth.

Primary and transplanted mammary tumors of the GR mouse were explanted in tissue culture and grown in the presence of radioactive fucose. Labelled membrane glycopeptides were isolated and compared by cochromatography with differentially labelled glycopeptides from normal mammary gland tissue. Differences with controls in the glycopeptide elution profiles were observed in autonomous, hormone-independent tumors but were absent in histologically similar tumors which required a continuous hormonal stimulus for growth. The results suggest that alterations in membrane glycopeptides are associated with the capacity of autonomous, hormone-independent growth of murine adenocarcinoma cells.