Studies on type II progesterone receptor in MCF-7 cells.
These experiments demonstrate for the first time the existence of a Type II progesterone receptor (RpII) in MCF-7 human breast cancer cells. RpII was shown to have a lower affinity for tritiated progesterone ([3H]Pg) (Kd greater than or equal to 13 nM) than classical Rp (Kd less than or equal to 3 nM). RpII was detected by cytosolic, nuclear, and whole cell assays of MCF-7 cells. Scatchard analysis of [3H]Pg binding data revealed that classical Rp but not RpII could be recompartmentalized from the cytosolic to the nuclear pool by treating cells 1 h at 37 degrees C with 1 microM Pg. RpII levels were shown to be increased more than two-fold by growing MCF-7 cells for 4 days in 10 nM estradiol (E2) plus 100 nM Pg when compared to either untreated cells or to cells treated with only E2.
Saunders
D E
DE
Department of Biochemistry, Wayne State University School of Medicine, Detroit, MI 48201.
Christensen
C
C
Brooks
S C
SC
D001943:Breast Neoplasms / Q000378:metabolism*; D004958:Estradiol / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D011374:Progesterone / Q000378:metabolism; D011980:Receptors, Progesterone / Q000302:isolation & purification*; D014407:Tumor Cells, Cultured
D011980:Receptors, Progesterone; D011374:Progesterone; D004958:Estradiol