Euchromatic histone lysine methyltransferase 2 (G9a, EHMT2) and suppressor of variegation 3-9 homolog 1 (SUV39H1) predominantly methylate histone H3K9 to induce the formation of heterochromatin, and are overexpressed in several types of cancer [99,100,101]. This evidence concerns the gene EHMT2 and cancer.