NAT10 and E2F1 Orchestrate CKAP5-Mediated Progression in Esophageal Squamous Cell Carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common and aggressive malignancy. N-acetyltransferase 10 (NAT10) has been implicated as an oncogenic promoter in ESCC. This study aimed to explore the molecular mechanisms through which NAT10 exerts its oncogenic functions in this malignancy. The influence on cell behaviors was evaluated by detecting cell viability, proliferation, apoptosis, invasion, and tube formation. Subcutaneous xenografts were generated to assess the role in vivo. Expression analysis was performed by quantitative PCR, immunoblotting, and immunohistochemistry. The NAT10/cytoskeleton-associated protein 5 (CKAP5) interaction was validated using RIP, ac4C-RIP, RNA pull-down, and mRNA stability assays. The E2F1/CKAP5 interaction was confirmed by luciferase reporter and ChIP-qPCR assays. NAT10 was upregulated in ESCC, and its deficiency exhibited anti-proliferation, pro-apoptosis, and anti-invasion effects in ESCC cells in vitro. Mechanistically, NAT10 increased CKAP5 mRNA stability in an ac4C-dependent manner. CKAP5 re-expression counteracted NAT10 deficiency-mediated anti-proliferation, pro-apoptosis, and anti-invasion effects in ESCC cells. Furthermore, E2F1 transcriptionally activated CKAP5 to increase its expression. E2F1 regulated ESCC cell proliferation, apoptosis, and invasion in vitro via CKAP5. Additionally, NAT10 deficiency exhibited anti-tumor activity in KYSE180 xenografts in vivo through CKAP5 downregulation. Our study mechanistically elucidates the NAT10/CKAP5 and E2F1/CKAP5 axes as critical novel pathways driving ESCC progression, providing promising therapeutic targets for this malignancy.