EP300 and neoplasm: Additionally, p300 has been reported to regulate tumor cell immunogenicity, p300 ablations prevent chemotherapy-induced processing and presentation of major histocompatibility class I (MHC-I) antigens and abrogating the rejection of low MHC-I-expressing tumors by reinvigorated CD8 cytotoxic T cells (CTLs) (Zhou et al., 2021).