NAT1, also known as N-acetyltransferase 1, is a polymorphic Phase II enzyme. It plays a crucial role in metabolizing heterocyclic and aromatic amines [1,4,5]. These metabolic processes are associated with various biological pathways related to carcinogen biotransformation. NAT1's function is of great biological importance as it can influence cancer susceptibility and other disease risks [1,4,5]. Genetic models, such as gene knockout models, can be valuable for studying NAT1.

In colorectal cancer, NAT1 overexpression inhibits the PI3K/AKT/mTOR signaling pathway, suppressing the epithelial-mesenchymal transition (EMT) process, glycolytic ability, and VEGF expression, ultimately reducing liver metastasis [2]. In breast cancer cells, NAT1 deletion leads to upregulation of cytidine deaminase, which is involved in the pyrimidine salvage pathway [3]. In mice, Nat1 deficiency (mouse ortholog of human NAT1) results in mitochondrial dysfunction, characterized by increased reactive oxygen species, mitochondrial fragmentation, and decreased mitochondrial functions, leading to exercise intolerance [7].

In conclusion, NAT1 is essential in processes like carcinogen metabolism and has a significant impact on diseases such as colorectal cancer, breast cancer, and potentially asthma in children with secondhand smoke exposure [6]. Mouse models, especially those with Nat1 deficiency, have revealed its role in mitochondrial function and provided insights into its contribution to disease-related biological processes.