CBX4 and breast cancer: Of the breast cancer related genes, thirty-five (41%) are nuclear proteins and 15 (17%) are transcription regulators [CBX4, EGR4, FHL2, GATA3, HEY2, MGA, MYB, NFATC2, NPAS4, PRDM1, PRDM2, RELB, RREB1, SMAD2, and ZNF3 (Figure 3C)].