GABPA and breast cancer: Both the BRCA1 and the BRCA2 promoter are bound and activated by ETS transcription factors: GA-binding protein α/β (GABPα/β) binds the RIBS element in the BRCA1 core promoter (Figure 1A), and overexpression of GABPα/β in breast cancer cells was able to stimulate BRCA1 promoter activation (66).