Estrogen gene suppression

Kuang TO et al. Differential screening and suppression subtractive hybridisation identified genes differentially expressed in an estrogen receptor-positive breast carcinoma cell line. Nucleic Acids Res 1998 26 1116-1123. 

Fibrinogen synthesis is stimulated by hormones such as the glucocorticoid dexamethasone or suppressed by the estrogen estadiol-17 (Amrani et al., 1983 Wangh et al, 1983). The three fibrinogen genes share a... 

This ER downregulation, can completely suppress the expression of estrogen-dependent genes, which likely explains why fulvestrant demonstrates efficacy against tamoxifen-resistant breast cancer. Maximum plasma concentrations are reached about 7 days after intramuscular administration of fulvestrant and are maintained over a period of 1 month. The plasma t is approximately 40 days. Steady-state concentrations are reached after 3-6 monthly injections. 

In an animal model of atherosclerosis E2 restores FasL expression, which is suppressed by atherogenic levels of serum cholesterol (328). High levels of Hey diminish with estrogen (reviewed in ref. 329). In HUVEC, E2 caused a decrease in expression of the NADPH oxidase subunit gp91phox, up-regulated eNOS expression, and inhibited the increase in adhesion molecule and chemokine expression in cells exposed to cyclic strain. Cyclic strain enhanced endothelial 02 formation, thereby offsetting the inhibitory effect of NO on the expression of these gene products (330). 

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