EP300 and cancer: In the unclassified subgroup, apart from previously reported mutations in epigenetic regulators in multiple cancers, including KMT2C, KMT2D, KMT2B, PRDM2, NCOR2, KAT6B, and EP300, in this cohort, we also found new recurrent mutations in epigenetic regulators, including CREBBP and PRDM16 (Figure 4B).