KAT7 promotes malignant phenotypes of colorectal cancer via MRAS-mediated activation of the MAPK/ERK pathway

Histone acetyltransferases (HATs) play a crucial role in transcriptional regulation by acetylating histones. Dysregulation of HAT activity is implicated in developmental disorders and cancer. In this study, we discovered an upregulated KAT7 signaling pathway in colorectal cancer (CRC) and its association with poor patient survival. Knockdown of KAT7 suppressed CRC cell viability, proliferation, migration, and invasion while promoting apoptosis. Conversely, KAT7 overexpression enhanced these cellular processes. In vivo experiments demonstrated that KAT7 knockdown inhibited CRC growth and lung metastasis. Mechanistically, KAT7 acetylated histone H3 at lysine 14 (H3K14) to enhance MRAS transcription, which activated the MAPK/ERK pathway and promoted tumorigenesis. Overexpression of MRAS or treatment with the ERK activator C6 Ceramide rescued the tumor inhibition caused by KAT7 silencing. The acetyltransferase activity of KAT7 is essential for CRC progression. Reexpression of KAT7, but not KAT7 acetyltransferase activity-deficient mutants, rescued MRAS expression, ERK phosphorylation, and CRC tumorigenesis in KAT7 knockdown CRC cells. Taken together, our results define the essential role of KAT7 in CRC tumorigenesis, rationalizing its potential as a therapeutic target for CRC treatment.