A comparable phosphorylation pattern, but modified CREB forms as demonstrated by two bands at ~90 and ~120 kDa were observed in the HER-2/neu+ breast cancer cell line SKBR3 under hypoxic treatment (Supplementary Figure 1C), while the 60 kDa band was neither visible with CREB nor with pCREB antibodies. Here, CREB1 is linked to breast carcinoma.