Estrogen receptor expression and growth-promoting function in human choriocarcinoma cells.

Abstract

Tamoxifen (1.0 microM) was found to inhibit the expression of a thymidine kinase (TK) promoter-reporter gene, lacking an estrogen response element (ERE), in transiently transfected BeWo cells, suggesting that inhibition of TK promoter activity was linked to secondary estrogen-dependent effects on BeWo cell function. Estradiol (0.05-0.45 microM) stimulated BeWo cell proliferation and increased the percentage of S-phase cells. Tamoxifen (1.35-4.05 microM) inhibited BeWo cell growth and antagonized the stimulatory actions of 0.15 microM estradiol. Reverse transcription-polymerase chain reaction and Western analyses confirmed the presence of estrogen receptor (ER) transcripts and the 67-kD ER in BeWo cells. The BeWo cell ER binds to an ERE consensus sequence and the ER-ERE complex is supershifted by antibodies directed against the ER. We conclude that BeWo cells express a functional ER that is important for the control of BeWo cell proliferation, suggesting a potential role for estrogens in mediating placental trophoblast growth and development.

• Authors: S W Jiang, R V Lloyd, L Jin, N L Eberhardt
• Journal: DNA and cell biology (DNA Cell Biol) Vol. 16 Issue 8 Pg. 969-77 (Aug 1997) ISSN: 1044-5498 [Print] United States
• PMID: 9303438 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• DNA Primers
• Oligodeoxyribonucleotides
• Receptors, Estrogen
• Recombinant Fusion Proteins
• Tamoxifen
• Estradiol
• Luciferases
• Thymidine Kinase

Topics

• Animals
• Base Sequence
• Binding Sites
• COS Cells
• Cell Cycle (drug effects)
• Cell Division (drug effects)
• Choriocarcinoma (metabolism, pathology)
• DNA Primers
• Estradiol (pharmacology)
• Female
• Gene Expression Regulation, Neoplastic
• Genes, Reporter
• Humans
• Luciferases (biosynthesis)
• Oligodeoxyribonucleotides
• Polymerase Chain Reaction
• Pregnancy
• Promoter Regions, Genetic
• Receptors, Estrogen (biosynthesis, physiology)
• Recombinant Fusion Proteins (biosynthesis)
• Tamoxifen (pharmacology)
• Thymidine Kinase (biosynthesis, genetics)
• Transcription, Genetic
• Transfection
• Tumor Cells, Cultured
• Uterine Neoplasms (metabolism, pathology)