Aberrant DNMT levels has been detected in many different cancer types through genome-wide analyses, which highlighted a ~5–10% increased methylation on CpG islands in cancer specimens compared to normal counterparts, with a consequent silencing of several tumor-suppressor genes (i.e., CDKN2B, RASSF1A, GATA4, CDH1), further supporting the tight correlation between epigenetics abnormalities and cancer initiation and progression [20,21,22,23,24]. This evidence concerns the gene GATA4 and cancer.