Regulation of Ubiquitin Mediated Proteolysis of G1 Cyclins and the CDK Inhibitor p27 by the Cullin Gene Family in Normal and Tumorigenic Human Breast Cells

1999 ◽  
Author(s):  
Jennifer J. Michel
Keyword(s):  
Gene Family ◽  
Cdk Inhibitor ◽  
Human Breast ◽  
G1 Cyclins ◽  
Breast Cells

scholarly journals Comparative activity of pulsed or continuous estradiol exposure on gene expression and proliferation of normal and tumoral human breast cells

2002 ◽  
Vol 28 (3) ◽  
pp. 165-175 ◽  
Author(s):  
V Cavailles ◽  
A Gompel ◽  
MC Portois ◽  
S Thenot ◽  
N Mabon ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Lines ◽  
Hormone Replacement ◽  
Primary Cultures ◽  
Continuous Treatment ◽  
Luciferase Reporter ◽  
Breast Cancer Cell Lines ◽  
Human Breast ◽  
Kinetic Profile ◽  
Breast Cells

Intranasal administration of hormone replacement therapy presents an original plasma kinetic profile with transient estrogen levels giving rise to the concept of pulsed therapy. To further understand the molecular effects of this new therapy, we have compared the effects of pulsed and continuous estradiol treatments on two critical aspects of estradiol action: gene expression and cell proliferation. Cells were stimulated with estradiol as 1-h pulsed or 24-h continuous treatments at concentrations such that the 24-h exposure (concentration x time) was identical in both conditions. In MCF7 cells, the transcriptional activity of estrogen receptors (ER) on a transiently transfected responsive estrogen response element-luciferase reporter construct was shown to be drastically (approximately 10-fold) and similarly stimulated after both treatments. Moreover, the increased mRNA expression of three representative estradiol-sensitive genes (pS2, cathepsin D, progesterone receptor), evaluated by Northern blot, was identical after 1-h pulse with 7 nM estradiol or continuous treatment with 0.29 nM estradiol with the same kinetic profile over 48 h. Proliferation was quantified by a histomorphometric method on primary cultures of human normal breast cells from reduction mammoplasties and using a fluorescence DNA assay in six human breast cancer cell lines which were ER positive or negative. After a 7-day treatment period, estradiol had no effect on the proliferation of the three ER negative cell lines (BT20, MDA MB231, SK BR3) but significantly stimulated the proliferation of the normal cells and of the three tumoral hormone-sensitive cell lines (MCF7, T47D, ZR 75-1); both hormone treatments producing the same increases in cell growth. In conclusion, we have shown that the genomic or proliferative effects of estradiol were identical with pulsed or continuous treatments, thus indicating that estrogenic effects are not strictly related to concentrations but rather to total hormone exposure.

scholarly journals Dietary estrogens stimulate human breast cells to enter the cell cycle.

1997 ◽  
Vol 105 (suppl 3) ◽  
pp. 633-636 ◽  
Author(s):  
C Dees ◽  
J S Foster ◽  
S Ahamed ◽  
J Wimalasena
Keyword(s):  
Cell Cycle ◽  
Human Breast ◽  
Breast Cells

The Influence of Steroid Hormones and Antihormones on the Growth and Differentiation of Normal Human Breast Cells in Culture

1992 ◽  
pp. 145-156 ◽  
Author(s):  
Frederique Kuttenn ◽  
Anne Gompel ◽  
Catherine Malet ◽  
Etienne Leygue ◽  
Nicole Baudot ◽  
...  
Keyword(s):  
Steroid Hormones ◽  
Human Breast ◽  
Cells In Culture ◽  
Normal Human Breast ◽  
Breast Cells ◽  
Normal Human
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