ESR2 and breast carcinoma: On the other hand, the mammary glands of combinational BPA + Gen treatment had significantly decreased Akt-1 and p-Atk protein expression compared to BPA only treatment.We assessed the expression of ER-α, ER-β and steroid receptor co-regulator (SRC) proteins known to play a role in estrogen signalling and breast cancer following prepubertal exposure to BPA or/and genistein.