The enrichment of CTCF motifs at Topo IIβ binding sites and the co-occupancy of Topo IIβ and CTCF at the same genomic locations has also been reported from analysis of relevant ChIP-seq datasets in primary mouse liver cells, human MCF-7 breast cancer cells, and primary B cells from mouse spleen [64,65,66]. This evidence concerns the gene CTCF and breast cancer.