Functional abnormality of glucocorticoid receptor in Shionogi carcinoma 115 cells as evidenced by gene transfer experiments.
The assay systems for steroid receptor functions in steroid-sensitive cells (SC-3 cells) were developed in which hormone-responsive element linked to a reporter gene [chloramphenicol acetyl transferase (CAT) gene] was transfected by the electroporation technique. Stimulation with androgen of SC-3 cells transfected with mouse mammary tumor virus promoter-CAT gene (MMTV-CAT) resulted in clear enhancement of CAT activity, whereas glucocorticoid required abnormally high concentrations to obtain significant stimulation. The simultaneous addition of glucocorticoid surprisingly inhibited androgen-induced CAT activity in SC-3 cells, whereas glucocorticoid and androgen acted together synergistically to activate CAT activity in T 47D cells. When SC-3 cells were cotransfected with the expression vector of human glucocorticoid receptor (GR) gene, inhibition with glucocorticoid of androgen-enhanced CAT activity was abolished. These results would suggest that SC-3 cells contain functionally abnormal GR.
Hirose
T
T
Third Department of Internal Medicine, Osaka University Hospital, Japan.
Koga
M
M
Saito
H
H
Kouhara
H
H
Sumitani
S
S
Kasayama
S
S
Matsumoto
K
K
Sato
B
B
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D003907:Dexamethasone; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D008325:Mammary Neoplasms, Experimental / Q000235:genetics* / Q000473:pathology; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics; D051379:Mice; D009376:Neoplasms, Hormone-Dependent / Q000235:genetics* / Q000473:pathology; D011965:Receptors, Glucocorticoid / Q000235:genetics / Q000502:physiology*; D013739:Testosterone / Q000494:pharmacology; D014162:Transfection; D014407:Tumor Cells, Cultured
D011965:Receptors, Glucocorticoid; D013739:Testosterone; D003907:Dexamethasone; D015500:Chloramphenicol O-Acetyltransferase