TGF-β, together with the tumor suppressor CTCF, epigenetically and/or transcriptionally regulate tumor promoter genes, including IGF2, TERT, and Myc in TGF-β–defective mice and in patients with Beckwith-Wiedemann syndrome (BWS), a human stem cell disorder [20]. Here, TGFB1 is linked to Beckwith-Wiedemann syndrome.