Table 1

ER and PGR expression levels in estrogen-dependent MCF-7Ca cells and estrogen-independent UMB-1Ca cells as determined by whole cell ligand binding assays

Cell LineERPGR (−E2)PGR (+E2)
KD (nm)Bmax (receptors/cell)KD (nm)Bmax (receptors/cell)KD (nm)Bmax (receptors/cell)
MCF-7Ca0.19 ± 0.05a55,534 ± 4,3180.62 ± 0.0424,493 ± 1,0700.58 ± 0.0986,142 ± 9,176
UMB-1Ca0.12 ± 0.01249,520 ± 11,015b0.42 ± 0.0618,434 ± 3,0620.63 ± 0.03241,580 ± 17,469c
  • a Values represent the mean and SE of at least three independent experiments.

  • b P < 0.0001 versus MCF-7Ca cells.

  • c P < 0.001 versus MCF-7Ca cells treated with E2 (1 nm).