This study was designed to explore the role of AIB1 in gastric tumorigenesis and its potential as a useful prognostic marker and therapeutic target in this cancer.
AIB1 is frequently overexpressed in breast cancer and has functions that promote oncogenesis that are independent of estrogen receptor (ER) coactivation.
The evolutionarily conserved AAA ATPase ANCCA (AAA nuclear coregulator cancer-associated protein)/ATAD2 was identified as a direct target of oncogene AIB1/ACTR/SRC-3 and a transcriptional coregulator for estrogen and androgen receptors and is strongly implicated in tumorigenesis.
Overexpression and activation of the steroid receptor coactivator amplified in breast cancer 1 (AIB1)/steroid receptor coactivator-3 (SRC-3) have been shown to have a critical role in oncogenesis and are required for both steroid and growth factor signaling in epithelial tumors.
Since AIB1 appears to modulate the effect of endogenous hormones via the estrogen receptor, and smoking affects circulating hormone levels, these results support evidence that steroid hormones play an important role in breast carcinogenesis in BRCA1 mutation carriers, and suggest mechanisms for developing novel cancer prevention strategies for BRCA1 mutation carriers.