Enhancer of Zeste homlog 2 (EZH2), the HMT within Polycomb repressive II complexes, is essential for not only methylation of histone H3 on Lys 27 (H3K27me3) but also interaction with and recruiting DNA methyltransferases to methylate CpG at certain EZH2 target genes to establish firm repressive chromatin structures, contributing to tumor progression and the regulation of development and lineage commitment both in ESCs and adult stem cells [53-55]. This evidence concerns the gene EZH2 and neoplasm.