Induction of the progesterone receptor gene in estrogen target cells monitored by branched DNA signal amplification.
Estrogens have multiple effects on the growth and development of cells in their target tissues, including the uterus, ovary, breast, bone marrow and brain. The hormone regulates the transcription of diverse genes in these tissues via the estrogen receptor, a nuclear transcription factor. Naturally occurring estrogens and estrogen analogs including selective estrogen receptor modulators (SERMs), constitute important therapies for breast cancer and osteoporosis, and are major components of oral contraceptives. The in vitro biologic activities of pharmaceutical estrogen agonists and antagonists have frequently been monitored by cotransfection assay, where exogenous estrogen receptor and reporter genes are transiently inserted into a heterologous, non receptor-containing cell line, such as those derived from kidney cells. Here we describe an alternative to this method, where induction of an endogenous estrogen-responsive gene, the progesterone receptor gene, is monitored by branched DNA signal amplification. Assays are performed with cultured cells derived from estrogen-responsive tissues; namely, breast, uterine endothelium and bone. Hormonal induction occurs via the endogenous estrogen receptor of these cells. Our data show that SERMs, which are estrogen agonists on bone in vivo, antagonize estrogen-dependent target gene induction in conditionally immortalized osteoblast-like cells.
Allan
G F
GF
Reproductive Therapeutics, R.W. Johnson Pharmaceutical Research Institute, Raritan, New Jersey, USA. gallan@prius.jnj.com
Hutchins
A
A
Liu
X
X
Clancy
J
J
D000469:Alkaline Phosphatase / Q000235:genetics; D001483:Base Sequence; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D021121:Branched DNA Signal Amplification Assay; D001940:Breast / Q000187:drug effects / Q000378:metabolism; D002460:Cell Line; D004727:Endothelium / Q000187:drug effects / Q000378:metabolism; D047628:Estrogen Receptor alpha; D004967:Estrogens / Q000378:metabolism / Q000494:pharmacology*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D020128:Inhibitory Concentration 50; D009838:Oligodeoxyribonucleotides / Q000235:genetics; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism; D053244:Osteoprotegerin; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020849:Raloxifene Hydrochloride / Q000494:pharmacology; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000235:genetics*; D018124:Receptors, Tumor Necrosis Factor; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology; D013629:Tamoxifen / Q000494:pharmacology; D015533:Transcriptional Activation; D014599:Uterus / Q000187:drug effects / Q000378:metabolism
D047628:Estrogen Receptor alpha; D004967:Estrogens; D006023:Glycoproteins; D009838:Oligodeoxyribonucleotides; D053244:Osteoprotegerin; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D018124:Receptors, Tumor Necrosis Factor; D020845:Selective Estrogen Receptor Modulators; C506030:TNFRSF11B protein, human; D013629:Tamoxifen; D020849:Raloxifene Hydrochloride; D000469:Alkaline Phosphatase