Open AccessReduced insulin endocytosis in serum‐transformed fibroblasts demonstrated by flow cytometry
Author(s) -
Murphy Robert F.,
Powers Scott,
Cantor Charles R.,
Pollack Robert
Publication year - 1984
Publication title -
cytometry
Language(s) - English
Resource type - Journals
eISSN - 1097-0320
pISSN - 0196-4763
DOI - 10.1002/cyto.990050310
Subject(s) - flow cytometry , endocytosis , cytometry , microbiology and biotechnology , insulin , chemistry , biology , endocrinology , cell , biochemistry
Abstract Neoplastic transformation often results in the loss of growth control and concomitant changes in cell surface properties. The changes in endocytosis of a variety of probes after serum or anchorage transformation were measured for mouse fibroblasts by flow cytofluorometry. No major differences in dextran (fluid phase) or histone (nonspecific‐adsorptive) endocytosis were observed among four cell lines with different growth properties. However, decreased receptor‐mediated internalization of α‐macroglobulin was observed for cell lines transformed to either serum or anchorage independence. Furthermore, increased wheat germ agglutinin and decreased insulin endocytosis were observed, but only in serum transformants. The changes specific to serum transformants were not accounted for by changes in binding of wheat germ agglutinin or insulin. The possible implications of these observations regarding serum transformation and the insulin requirement for growth in serum‐free medium are discussed.