KMT2B and cancer: UTX (KDM6A), MLL3 (KMT2C), and MLL4 (KMT2D), the core catalytic components of the COMPASS-like complex, are all considered tumor suppressors, with frequent loss-of-function genomic alterations found in a broad spectrum of human cancers (Revia et al., 2022; Sze and Shilatifard, 2016).