KAT7 is a lysine acetyltransferase that catalyzes histone acetylation and other acyl modifications to regulate gene expression across multiple biological contexts. KAT7 mediates acetylation of histone H3 at lysine 14 (H3K14ac) and catalyzes histone β-hydroxybutyrylation (H3K9bhb) and crotonylation, facilitating RNA polymerase II processivity and transcriptional regulation 1. The enzyme functions as a histone lactyltransferase affecting H4K16 lactylation in vascular smooth muscle cells 2. KAT7 plays critical roles in disease pathogenesis. In acute myeloid leukemia, KAT7 maintains leukemia stem cell function through HOXA9/HOXA10 activation and associates with NUP98 fusion oncoproteins to drive NUP98-rearranged leukemia 3. In colorectal cancer, KAT7 promotes MRAS transcription via H3K14 acetylation, activating the MAPK/ERK pathway and enhancing tumorigenesis 4. KAT7 also regulates procentriole formation through competitive antagonism between its crotonylation and acetylation 5. Conversely, KAT7 inhibition alleviates cellular senescence in aging and progeroid conditions by repressing p15INK4b transcription 6, and reduces aortic aneurysm progression 2. KAT7 mediates MTORC1 pathway sensitivity to leucine through calnexin crotonylation 7. These findings establish KAT7 as a therapeutically actionable epigenetic regulator with context-dependent roles in cancer and aging.