The potential of NAT10-mediated ac4C acetylation in clinical translation

Abstract

RNA modifications have recently garnered significant attention as key players in epigenetic regulation,¹ such as N6-methyladenosine (m6A), pseudouridine (ψ), N1-methyladenosine (m1A), N4-acetylcytidine (ac4C), 5-methylcytosine (m5C) and its oxidised product 5-hydroxymethylcytosine (hm5C). N-acetyltransferase 10 (NAT10), the sole enzyme identified for ac4C acetylation, modulates RNA stability, translation efficiency and metabolic reprogramming, thereby impacting cellular homeostasis and disease progression. This commentary highlights the multifaceted roles of NAT10 in health and disease, emphasising its potential as a therapeutic target.

NAT10 is a multifunctional enzyme belonging to the GCN5-related N-acetyltransferase (GNAT) family. The NAT10 gene is located on chromosome 11p13 and comprises 29 exons and 28 introns, encoding a 1025-amino acid protein. NAT10 is highly conserved from bacteria to humans, featuring both an acetyltransferase domain and an RNA-binding domain.² It catalyses the acetylation of specific RNA transcripts using acetyl-CoA as a substrate, primarily modifying tRNAs, rRNAs and mRNAs at specific sites. These modifications alter the structure and function of these RNA molecules, mainly to maintain mRNA stability and to enhance translation efficiency.³ However, the precise molecular mechanisms by which NAT10 increases mRNA stability through ac4C modification remain to be fully elucidated, requiring further in-depth research.

NAT10 plays diverse roles in cellular metabolism, cancer progression, cardiac injury, viral replication and other physiological and pathological processes. It directly regulates mRNA stability and translation efficiency through ac4C modification (e.g., SLC30A9, Mybbp1a) and interacts with other proteins to modulate key signalling pathways.^{4, 5} Additionally, NAT10 possesses biological functions independent of its classical RNA acetyltransferase activity (i.e., ac4C modification). These include roles in DNA repair, cytoskeletal regulation and epigenetic regulation via distinct molecular mechanisms.⁶ NAT10 is emerging as a potential therapeutic target in diseases such as cancer, cardiac injury and viral infections. Inhibiting its acetyltransferase activity or blocking its downstream signalling may provide novel therapeutic strategies.

NAT10-mediated ac4C modification of mRNA plays a significant role in various tumour-related processes. NAT10 enhances p53 stability and transcriptional activity by acetylating specific lysine residues on p53, thereby contributing significantly to tumour suppression.⁷ Conversely, upregulated NAT10 expression can promote the development of certain cancers by enhancing the stability and translation efficiency of target mRNA through ac4C modification. For instance, in bladder cancer, downregulation of NAT10 reduces ac4C modification, impairing the translation efficiency and stability of BCL9L, SOX4 and AKT1, thereby weakening tumourigenicity.⁸ In gastric cancer, NAT10-mediated ac4C acetylation of MDM2 mRNA stabilises the transcript and upregulates its expression, leading to p53 inhibition and cancer progression.⁹ In diffuse large B-cell lymphoma (DLBCL), NAT10 enhances SLC30A9 mRNA stability via ac4C modification, activating the AMPK/mTOR signalling pathway and promoting DLBCL progression.⁴ NAT10 is highly expressed in most cancer tissues and may also be associated with fatty acid metabolism pathways regulated by NAT10-mediated ac4C modification. It modulates the mRNA stability of fatty acid metabolism-related genes through ac4C modification, thereby influencing lipid accumulation and supporting cancer cell survival.¹⁰ In breast cancer, high NAT10 expression confers enhanced lipid utilisation and fatty acid metabolism, suggesting that NAT10 inhibition could be a potential target for cancer therapy.¹¹ In haematological malignancies, overexpressed NAT10 correlates with poor prognosis and chemoresistance in acute myeloid leukaemia (AML) patients. NAT10 inhibition leads to G1 phase cell cycle arrest and promotes apoptosis in AML cells. Moreover, NAT10 stabilises BCL-XL mRNA and enhances its translation, thereby inhibiting apoptosis and promoting MM cell proliferation.¹²

NAT10 is also linked to cardiovascular diseases and immune regulation. Its expression is upregulated during vascular remodelling, inducing phenotypic switching in vascular smooth muscle cells (VSMCs). NAT10 knockdown decreased ac4C expression, leading to the upregulation of contractile marker genes (e.g., α-SMA, Calponin, SM22) in VSMCs. These findings suggests that NAT10 promotes VSMC phenotypic switching through mRNA ac4C acetylation. Additionally, NAT10 facilitates neointima formation and VSMC phenotypic switching following vascular injury. The study identified integrin-β1 (ITGB1) and collagen type I alpha 2 chain (Col1a2) as key downstream targets of NAT10. NAT10-mediated ac4C modification enhances the stability of these mRNAs, leading to increased ITGB1 and COL1A2 expression, which promotes VSMC proliferation and vascular remodelling.¹³ By regulating gene expression at multiple levels through both histone acetylation and mRNA modification, NAT10 represents a complex regulatory network for therapeutic intervention. Further studies have explored the functional significance of ITGB1 in NAT10-mediated vascular remodelling. In rheumatoid arthritis (RA), NAT10 increases PTX3 mRNA N4-acetylation, enhancing its stability and translation efficiency, thereby promoting RA synovial invasion and immune cell infiltration. This highlights the importance of NAT10 in RA pathogenesis and suggests it as a potential target for future RA interventions.¹⁴

Acting on different target genes promote different tumour development though NAT10-mediated ac4C acetylation.

Remodelin, a small-molecule inhibitor, suppresses NAT10 expression and its downstream targets, inhibiting cell growth and promoting cell cycle arrest. It exhibits antitumour effects in various cancers by promoting apoptosis, inducing cellular senescence, and reversing epithelial‒mesenchymal transition and hypoxia conditions.¹⁵ Remodelin inhibits the proliferation, migration and invasion of multiple cancer cell types, making it a promising candidate for cancer therapy. Yu et al. confirmed that Remodelin treatment reduces NAT10 and ITGB1 expression, decreases neointima formation and VSMC proliferation, and inhibits the ITGB1‒FAK signalling activity.¹³ These findings suggest that NAT10 is a potential therapeutic target for vascular remodelling-related diseases such as atherosclerosis and in-stent restenosis. However, further research is needed to understand the broader cellular implications of NAT10 inhibition on overall cellular function and to assess potential off-target effects. Ma et al. found that NAT10 regulates the expression of Uqcr11 and Uqcrb mRNA in both mouse and human cardiomyocytes. In mice, overexpression of NAT10 in cardiomyocytes promoted cardiac regeneration and improved post-injury heart function.¹⁶ Conversely, either genetic deletion of NAT10 or Remodelin treatment in neonatal mice impaired cardiac regeneration. Mechanistically, NAT10 suppresses Uqcr11 and Uqcrb expression independently of its ac4C enzymatic activity. Comparative studies across different disease models will be essential to identify shared and distinct mechanisms of NAT10 function.

Growing evidence continues to deepen our understanding of the relationship between NAT10 and various diseases. NAT10 acts both as an oncogene and as a key regulator of RNA epigenetic modification, showing upregulated expression in diseases and cancers. However, the target genes regulated by NAT10-mediated ac4C modification vary significantly among different disease and cancer types, highlighting the need for further research into the universality and specificity of its downstream effects. While NAT10 is a potential therapeutic target for conditions such as cancer, cardiac injury and viral infections, strategies that inhibit its acetyltransferase activity or block-related signalling pathways may offer novel therapeutic opportunities. Nevertheless, since NAT10 is currently the only known ac4C-regulating enzyme, the absence of enzymatic redundancy limits its broad applicability as a drug target. Although Remodelin effectively inhibits NAT10 expression and reduces ac4C levels, its precise mechanism of action remains incompletely understood.

Xuqiao Mei, Wanxin Duan and Jiawei hu wrote this article, Shihiyu Zheng, Yuhuang Xu, Yongguang Zhang, Jiangming Weng reviewed and organized relevant papers, Xiao Yang reviewed this manuscript.

This research was approved by the Ethics Committee of Zhangzhou Affiliated Hospital of Fujian Medical University.