Comparing specific lost/gained CTCF sites from the six cancer types, we observed that different cancer types share few commonly gained sites (Jaccard index < 0.03), much less than shared all CTCF sites between each other (Jaccard index between 0.33 and 0.71), indicating cancer-type specificity of the identified CTCF sites (Fig. 1g, Additional file 1: Fig. S2d, Additional file 5: Table S4). Here, CTCF is linked to cancer.