TY - JOUR
T1 - Presence and steroid inducibility of glutamine synthetase in human leukemic cells
AU - Marchetti, Paolo
AU - Ranelletti, Franco O.
AU - Natoli, Vittoria
AU - Sica, Gigliola
AU - Rossi, Giulio De
AU - Iacobelli, Stefano
PY - 1983
Y1 - 1983
N2 - Glutamine synthetase (EC 6.3.1.2; GS) is present in lymphoblasts from patients with acute lymphoblastic leukemia (ALL) as well as in normal peripheral blood lymphocytes. In 16 out of 20 ALL patients studied exposure of the cells to physiological concentrations of dexamethasone in vitro increased enzyme activity above the control levels. The increase was specific for glucocorticoid receptor ligands. A direct correlation was found between the magnitude of glucocorticoid-mediated increase of GS activity and the cellular levels of specific glucocorticoid receptors assayed in the same cell specimen. Moreover, the basal levels of the enzyme measured in cells prior to exposure to dexamethasone correlated negatively with receptor density. It is suggested that the presence of steroid-inducible GS in ALL cells may prove to be a marker for functional receptor sites.
AB - Glutamine synthetase (EC 6.3.1.2; GS) is present in lymphoblasts from patients with acute lymphoblastic leukemia (ALL) as well as in normal peripheral blood lymphocytes. In 16 out of 20 ALL patients studied exposure of the cells to physiological concentrations of dexamethasone in vitro increased enzyme activity above the control levels. The increase was specific for glucocorticoid receptor ligands. A direct correlation was found between the magnitude of glucocorticoid-mediated increase of GS activity and the cellular levels of specific glucocorticoid receptors assayed in the same cell specimen. Moreover, the basal levels of the enzyme measured in cells prior to exposure to dexamethasone correlated negatively with receptor density. It is suggested that the presence of steroid-inducible GS in ALL cells may prove to be a marker for functional receptor sites.
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U2 - 10.1016/0022-4731(83)90388-6
DO - 10.1016/0022-4731(83)90388-6
M3 - Article
C2 - 6139509
AN - SCOPUS:0021020593
VL - 19
SP - 1665
EP - 1670
JO - Journal of Steroid Biochemistry
JF - Journal of Steroid Biochemistry
SN - 0022-4731
IS - 5
ER -