Amplification and overexpression of peroxisome proliferator-activated receptor binding protein (PBP/PPARBP) gene in breast cancer.

ABSTRACT: Peroxisome proliferator-activated receptor binding protein (PBP), a nuclear receptor coactivator, interacts with estrogen receptor alpha (ERalpha) in the absence of estrogen. This interaction was enhanced in the presence of estrogen but was reduced in the presence of antiestrogen, tamoxifen. Transfection of PBP in CV-1 cells resulted in enhancement of estrogen-dependent transcription, indicating that PBP serves as a coactivator in ER signaling. To examine whether overexpression of PBP plays a role in breast cancer because of its coactivator function in ER signaling, we determined the levels of PBP expression in breast tumors. High levels of PBP expression were detected in approximately 50% of primary breast cancers and breast cancer cell lines by ribonuclease protection analysis, in situ h

SUBMITTER: Zhu Y 

PROVIDER: S-EPMC17971 | biostudies-literature | 1999 Sep

REPOSITORIES: biostudies-literature