CIZ1 and breast cancer: Evaluation of cultured tumor-derived cell lines showed that CIZ1-F transcript is elevated in MCF7 breast cancer cells compared to normal MCF-10A breast cells (Supplementary Figure 1(d)), and is in fact one of the main CIZ1 PCR-products (Supplementary Figure 1(a)), identifying MCF7 cells as a model cell line to study the function of CIZ1-F in cell proliferation.