For example, a gene regulated by TGF-β only in MDA-MB-231 BTICs (MDA-unique gene) can be: (1) uniquely bound by SMAD3 in MDA-MB-231 (binding mode 1), (2) uniquely bound by SMAD3 in HCC-1954 (binding mode 2), (3) commonly bound by SMAD3 in both cell types (binding mode 3), and (4) not bound by SMAD3 in either cell type (binding mode 4). Here, TGFB1 is linked to hepatocellular carcinoma.