GATA4 and colonic neoplasm: We next tested whether the GATA-4 locus has different or similar spatial organization in the adult colon cancer cell line (HCT116), where the gene promoter is known to be DNA hypermethylated [38,42] and tightly silenced to a degree where transcription is essentially absent as compared with the low expression levels in the undifferentiated Tera-2 cells (Figure 2A).