Similarly, the histone methyltransferase EZH2, which catalyzes the methylation of lysine 27 on histone H3 (H3K27), has been shown to promote CCA development and progression in vitro, while corresponding TCGA data revealed worse survival rates in CCA patients expressing high EZH2 levels (Zhang et al. 2022). This evidence concerns the gene PRDM9 and cholangiocarcinoma.