bcrp - publications

Predict more bcrp - ligand interactions now!

1. Cancer Sci. 2012 Feb 20. doi: 10.1111/j.1349-7006.2012.02245.x. [Epub ahead of

Progesterone Receptor Down-Regulates BCRP Expression via Binding to the
Progesterone Response Element in Breast Cancer.

Wu X, Zhang X, Zhang H, Su P, Li W, Li L, Wang Y, Liu W, Gao P, Zhou G.

Department of Pathology, School of Medicine, Shandong Univeristy, Shandong,

Breast cancer resistance protein (BCRP) plays a major role in multidrug
resistance (MDR). Sequence analysis reveals there is a novel progesterone
response element (PRE) in the BCRP promoter, suggesting progesterone receptor
(PR) may have a function in the regulation of BCRP expression. We examined the
expressions of BCRP, PR, ERα, AR and Her-2 in 95 breast cancer samples by
immunohistochemistry. Then, to identify the role of PR in the regulation of BCRP
expression, two constructs encoding full length BCRP cDNA driven by putative PRE
promoter or constitutive CMV promoter were transfected into MCF-7 and MDA-MB-231,
respectively. RT-PCR and Western blotting were used to detect the expression of
BCRP. Further electrophoretic mobility shift assay (EMSA) was utilized to verify
the nuclear protein-DNA specific binding. We innovatively found that the
expression of BCRP negatively related with that of PR and ERα in breast cancer by
immunohistochemistry. While in cellular level, after treated by progesterone and
17β-estradiol, BCRP mRNA and protein levels were significantly reduced in a
concentration-dependent manner in MCF-7/P-BCRP cells with PR bound to the
identified PRE in BCRP promoter. Our results demonstrated that active PR
inactived BCRP expression via progesterone-PR complexes binding to PRE in BCRP
promoter in breast cancer cells. © 2012 Japanese Cancer Association.

© 2012 Japanese Cancer Association.

PMID: 22348324 [PubMed - as supplied by publisher]