The growth-inhibiting peptide hormone somatostatin stimulates phosphotyrosine phosphatase activity in the human pancreatic cell line MIA PaCa-2. This hormonal activation was mediated by a pertussis toxin-sensitive guanosine 5'-triphosphate-binding protein (G protein) in the membranes of these cells. Activation of this G protein by somatostatin stimulated the dephosphorylation of exogenous epidermal growth factor receptor prepared from A-431 cells in vitro. This pathway may mediate the antineoplastic action of somatostatin in these cells and in human tumors and could represent a general mechanism of G protein coupling that is utilized by normal cells in the hormonal control of cell growth
G PROTEIN ACTIVATION OF A HORMONE-STIMULATED PHOSPHATASE IN HUMAN TUMOR CELLS
FLORIO, TULLIO;
1992-01-01
Abstract
The growth-inhibiting peptide hormone somatostatin stimulates phosphotyrosine phosphatase activity in the human pancreatic cell line MIA PaCa-2. This hormonal activation was mediated by a pertussis toxin-sensitive guanosine 5'-triphosphate-binding protein (G protein) in the membranes of these cells. Activation of this G protein by somatostatin stimulated the dephosphorylation of exogenous epidermal growth factor receptor prepared from A-431 cells in vitro. This pathway may mediate the antineoplastic action of somatostatin in these cells and in human tumors and could represent a general mechanism of G protein coupling that is utilized by normal cells in the hormonal control of cell growthI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.