Chemotherapy-induced acetylation of ACLY by NAT10 promotes its nuclear accumulation and acetyl-CoA production to drive chemoresistance in hepatocellular carcinoma

Abstract

Chemotherapeutic efficacy is seriously impeded by chemoresistance in more than half of hepatocellular carcinoma (HCC) patients. However, the mechanisms involved in chemotherapy-induced upregulation of chemoresistant genes are not fully understood. Here, this study unravels a novel mechanism controlling nuclear acetyl-CoA production to activate the transcription of chemoresistant genes in HCC. NAT10 is upregulated in HCC tissues and its upregulation is correlated with poor prognosis of HCC patients. NAT10 is also upregulated in chemoresistant HCC cells. Targeting NAT10 increases the cytotoxicity of chemotherapy in HCC cells and mouse xenografts. Upon chemotherapy, NAT10 translocates from the nucleolus to the nucleus to activate the transcription of CYP2C9 and PIK3R1. Additionally, nuclear acetyl-CoA is specifically upregulated by NAT10. Mechanistically, NAT10 binds with ACLY in the nucleus and acetylates ACLY at K468 to counteract the SQSTM1-mediated degradation upon chemotherapy. ACLY K468-Ac specifically accumulates in the nucleus and increases nuclear acetyl-CoA production to activate the transcription of CYP2C9 and PIK3R1 through enhancing H3K27ac. Importantly, K468 is required for nuclear localization of ACLY. Significantly, ACLY K468-Ac is upregulated in HCC tissues, and ablation of ACLY K468-Ac sensitizes HCC cells and mouse xenografts to chemotherapy. Collectively, these findings identify NAT10 as a novel chemoresistant driver and the blockage of NAT10-mediated ACLY K468-Ac possesses the potential to attenuate HCC chemoresistance.