Please use this identifier to cite or link to this item:
Title: Differential regulation of cyclic AMP synthesis by estrogen in MCF7 cells
Authors: Chan, R
Wong, MS 
Keywords: cAMP
Chronic and short-term estrogen treatment
Estrogen receptor
G proteins
Issue Date: 2007
Publisher: Academic Press
Source: Biochemical and biophysical research communications, 2007, v. 363, no. 3, p. 616-620 How to cite?
Journal: Biochemical and biophysical research communications 
Abstract: The classical view of the molecular actions of estrogen is described by its interaction with the intracellular estrogen receptor (ER), the binding of hormone receptor complex to the estrogen response element (ERE) on the DNA and followed by the alterations of gene expressions. Recently it has been reported that membrane estrogen receptor (mER) exist and it is suggested to be G protein linked receptor. In this report we show that under steroid-free culture conditions supplemented with low percentage of charcoal-stripped serum, differential estrogen treatments of human breast cancer MCF7 cells induce different responses of cyclic AMP (cAMP) productions. Treating [2-3H]adenine-labeled MCF7 cells with 1 nM estrogen for 30 min stimulates cAMP production by measuring the ratio of [3H]cAMP:Total [3H]adenine nucleotides (ATP + ADP + cAMP), as determined by column chromatography, when compared with the control. This short-term estrogen treatment also significantly enhanced forskolin stimulated cAMP production when compared with the ratio of cAMP/Total measured in cells stimulated with forskolin alone. Pre-treating MCF7 cells with the same concentration of estrogen for 24 h before the assay, on the contrary, significantly decreased the basal cAMP level and it also suppressed cAMP production stimulated with forskolin when compared with its respective value under short-term estrogen treatment. Estrogen receptor antagonist ICI 182780 abolished both the stimulatory and suppressive effect of estrogen on cAMP synthesis indicating both effects were mediated through ER. Pre-treating cells with pertussis toxin relieved the suppression of cAMP synthesis by chronic estrogen treatment. Our data suggest that estrogen exerts differential effects on the cAMP production in MCF7 cells, involving the activations Gαi and Gαs family of G proteins, depending on the length of time of hormone treatment.
ISSN: 0006-291X
EISSN: 1090-2104
DOI: 10.1016/j.bbrc.2007.09.005
Appears in Collections:Journal/Magazine Article

View full-text via PolyU eLinks SFX Query
Show full item record


Last Week
Last month
Citations as of Apr 20, 2018


Last Week
Last month
Citations as of Apr 17, 2018

Page view(s)

Last Week
Last month
Citations as of Apr 15, 2018

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.