PRDM9 and glioblastoma: To address the essential role of ASH2L for glioblastoma cell survival further, we focused our attention to chromatin modifying complexes, specifically, SET1/MLL family of histone methyltransferases SET1 (SETD1A), SET1B (SETD1B), MLL1 (KMT2A), MLL2 (KMT2B), MLL3 (KMT2C) and MLL4 (KMT2D) [28].