SETDB1 and neoplasm: For example, polycomb protein EZH2 is essential in stem cell self-renewal and has been shown to promote expansion of breast CSCs [35], histone methyltransferase SETDB1 is a bona fide oncogene and contributes to tumorigenesis [34], histone lysine methyltransferase SMYD3 plays a pivotal role in the regulation of oncogenic signaling [36], and MLL creates epigenetic changes and maintains tumor propagating cells in response to Wnt/β-catenin signaling [37].