Endocrine Abstracts

In breast cancer associations between p160 co-activator proteins and the development of resistance to endocrine treatment have been shown. We hypothesized that nuclear co-regulatory proteins may interact with non-steroid receptors. We investigated the effect of silencing the co-activator, SRC-1, on tumour cell growth in vitro. We also examined the MAPK activated transcription factors, Ets, as possible interaction proteins of the co-activator SRC-1 in human breast cancer. The e...

Introduction: Regulation of HER2 through the transcription factor PEA3 is associated with tumour progression and resistance to endocrine treatment in human breast cancer. The mechanism of this resistance remains unclear. Activation of estrogen receptor co-activator proteins via the MAP-kinase pathway is thought to be central to tamoxifen insensitivity. We hypothesised that activation of HER2 by PEA3 may result in activation of co-activator proteins such as AIB1 (amplified-in-b...

Her-2/neu over-expression is associated with elevated tumorigenicity and enhanced metastatic potential. Recently a DNA motif containing the consensus binding site of PEA3, a member of the ets transcription factor family has been identified on the Her-2/neu promoter. Activation of the PEA3 response element has been proposed to be involved in the transcriptional squelching of Her-2/neu.Methods: Using RT-PCR we have determined PEA3 mRNA expression in human breast tissue and l...