EZH2 and central nervous system cancer: Enhancer of Zeste-Homolog 2 (EZH2), Enhancer of Zeste-Homolog 3 (EZH3) and H3K27(lysine residue at position 27 of histone 3) KMTs were found at elevated levels in glioma, breast and leukemia CSCs, and are credited with maintaining their quiescent state [31].