Cyclosporine A inhibition of prolactin-dependent up-regulation of BRCA1 protein expression in human breast cell lines.
BACKGROUND
Previously, we reported experimental evidence that BRCA1, breast and ovarian cancer susceptibility gene is up-regulated in response to Prolactin stimulation. In this work, we studied the effects of Cyclosporine A and the competition with Prolactin on BRCA1 protein expression in vitro.


METHODS
The expression of BRCA1 was monitored in a human breast cancer cell line (MCF7) by comparison with a normal breast epithelial one (MCF10a) treated with Cyclosporine A and ovine Prolactin. The amount of BRCA1 protein expression was quantified using a strategy of two successive affinity perfusion chromatographies.


CONCLUSIONS
We showed that Prolactin in presence of Cyclosporine A has no effect on BRCA1 protein expression in human breast cell lines. This emphasized the hypothesis that BRCA1 may be stimulated by Prolactin.
Favy
D A
DA
Laboratoire d'Oncologie Moléculaire, INSERM CRI 9502, Clermont-Ferrand, France.
Rio
P G
PG
Vissac
C
C
Maurizis
J C
JC
Bignon
Y J
YJ
Bernard-Gallon
D J
DJ
D019313:BRCA1 Protein / Q000096:biosynthesis* / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism; D016572:Cyclosporine / Q000494:pharmacology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D011388:Prolactin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000187:drug effects
D019313:BRCA1 Protein; D007166:Immunosuppressive Agents; D016572:Cyclosporine; D011388:Prolactin